dp19a9

ExxonMobil ProprietaryWATER POLLUTION CONTROL Section Page

WATER / WASTEWATER XIX-A9 1 of 35

DESIGN PRACTICES CHEMICAL FEED SYSTEMS December, 2002

ExxonMobil Research and Engineering Company – Fairfax, VA

CONTENTS

Section Page

SCOPE 2

REFERENCES.................................................................................................................................................2

DESIGN PRACTICES .............................................................................................................................2

GLOBAL PRACTICES.............................................................................................................................2

WATER AND WASTEWATER DESIGN GUIDE (emre Manual No. TMEE 080).....................................2

OTHER REFERENCES ..........................................................................................................................2

DEFINITIONS ..................................................................................................................................................3

BACKGROUND...............................................................................................................................................4

WASTEWATER TREATMENT........................................................................................................................5

COAGULATION / COAGULATION AID ..................................................................................................5

NUTRIENT ADDITION ............................................................................................................................7

pH ADJUSTMENTS ................................................................................................................................8

OXIDANTS ............................................................................................................................................10

FOAM CONTROL..................................................................................................................................11

COOLING WATER TREATMENT .................................................................................................................11

BIOLOGICAL CONTROL ......................................................................................................................11

CORROSION CONTROL......................................................................................................................12

PH ADJUSTMENT ................................................................................................................................13

BOILER FEED WATER TREATMENT..........................................................................................................14

CONTROL AND MONITORING ....................................................................................................................14

CHEMICAL PREPARATION AND HANDLING.............................................................................................14

Dry Feed Systems.................................................................................................................................15

Dry Materials (in bags) ..........................................................................................................................16

TABLESTable 1 Summary of Typical Chemical Applications........................................................................17Table 2 Properties and Handling Considerations for Commonly Used Chemicals ..........................19Table 3 Standard Water / Wastewater Analysis Sheet ....................................................................28Table 4 Selection Chart for Bench Scale Polymer Testing Procedure............................................ 29

FIGURESFigure 1 Controlled Volume Pump Feeder ......................................................................................30Figure 2 Typical Dry Chemical Feeder ............................................................................................31Figure 3 Anionic and Nonionic Polyelectrolyte Feed System...........................................................32Figure 4 Cationic Polyelectrolyte Feed System ...............................................................................33Figure 5 Flow Through Solid Feeder for Hydantoin Chemical(6).....................................................34Figure 6 Typical Recirculated Cooling Water System.......................................................................35

Revision Memo12/02 Removed data from Properties of comercially available acids and bases tables.

Added chemicals in Table 1.Added detail in Table 2.

Changes shown by ➧

ExxonMobil ProprietarySection Page WATER POLLUTION CONTROL

XIX-A9 2 of 35 WATER / WASTEWATERDecember, 2002 CHEMICAL FEED SYSTEMS DESIGN PRACTICES


SCOPEThis section presents guidelines for the use of chemicals in wastewater, cooling water, and boiler water treatments. Thechemical applications, the injection points, and control and monitoring issues are discussed. Information on the applicability ofthe most commonly used water / wastewater chemicals is provided along with general guidelines for handling and feeding thechemicals.

REFERENCESDESIGN PRACTICESSection XXVI-A Boiler Feedwater Treating SystemsSection XXVII Cooling Water SystemsSection XIX-A Guidelines for Selecting Wastewater Treatment SystemsSection XIX-A2 Flotation UnitsSection XIX-A3 Media FiltrationSection XIX-A4 Coagulation / Flocculation / Clarification EquipmentSection XIX-A5 Biological Treatment of WastewaterSection XIX-A11 Chemical OxidationSection XX-A1 Dissolved Air Flotation Sludge ThickeningSection XX-A3 Mechanical Sludge Dewatering

GLOBAL PRACTICESGP 8-1-1 Cooling TowersGP 9-4-2 Additional Requirements for Atmospheric Storage Tanks for AcidsGP 19-6-1 Facilities for Corrosion Monitoring in Process Equipment

WATER AND WASTEWATER DESIGN GUIDE (EMRE Manual No. TMEE 080)DG 11-2-1 Fixed Bed Ion Exchange Water Treating UnitsDG 11-2-2 Aqueous Membrane SystemsDG 11-3-1 Gas Chlorinators for Water Treating ServiceDG 11-4-1 Hot Process Water TreatersDG 11-4-2 Cold Process Water TreatersDG 11-6-1 Chemical Feeders for Boilers and DeaeratorsDG 11-6-2 Chemical Feeders for Cooling Towers (Leased or Purchased)DG 11-6-3 Chemical Feeders for Wastewater TreatingDG 11-7-1 Wastewater Dissolved-Air Flotation SystemDG 11-7-2 Wastewater Induced Gas Flotation SystemDG 11-8-1 Gravity Belt-Filter Press System

OTHER REFERENCES1. Betz Handbook of Industrial Water Conditioning, 7th Edition (1976).2. Devine, T. A., Guidelines for Safety Evaluation of Chemical Injection Facilities, EE.92E.94 (December 1994).3. Franco, R. J., Environmentally Acceptable Cooling Water Treatment, EE.34E.86 (March 1986).4. Kemmer, F. N., ed., The Nalco Water Handbook, 2nd Edition, McGraw-Hill Book Company (1988).5. Kilpert, R., et al, Cooling Tower Water Treatment Guidelines, EE.102E.78 (November 1978).6. Robertaccio, F. L., Polyelectrolyte Guide, EE.20E.84 (February 1984).7. Smith & Loveless, Inc., Engineering Data, Water & Wastewater Treatment Systems Chem-Tower Notes on Design (1989).8. Water Environment Research Foundation, Project 91-ISP-5, Guidance Manual for Polymer Selection in Wastewater

Treatment Plant, (1993).9. Wolfe, E. I., et al., New Guide to Boiler Water Treatment, EE.2E.86 (January 1986).





10. Metcalf & Eddy, Inc., Wastewater Engineering Treatment, Disposal, and Reuse, 3rd Edition (1991).11. Refinery Construction Materials Manual, EMRE Manual No. EETD 028.

DEFINITIONSAlkalinity - A measure of water's capacity to neutralize acids. Includes the total carbonate, bicarbonate, and hydroxide ionconcentration in the water expressed in ppm (mg/l) as calcium carbonate (CaCO3) equivalent. Alkalinity is measured by doubletitration with acid and Phenolphthaline (P) and Methyl Orange (MO or M) indicators. The M-alkalinity includes carbonate,bicarbonate and hydroxyl ions and the P-alkalinity includes all hydroxyl and 1/2 of the carbonate ions.Anions - Negatively charged ions in the water (e.g., sulfates, chlorides, nitrates, bicarbonates, etc.).Baumé (Bé) - This unit is often followed by “Am. Std." which signifies “American Standard Baumé Scale." For liquids heavierthan water, this scale is defined by the formula:

Degree Baumé = F60/60atGravitySpecific

145145��

− Eq. (1)

Brine - A solution of sodium chloride in water.Bulking - A condition in the settling basin of a biological oxidation system where the sludge doesn't settle, or settles slowly, andmay lead to floc carryover with the effluent.Calcium Hardness - The concentration of calcium ion in the water, expressed in ppm (mg/l) generally as calcium carbonate(CaCO3) equivalent.Cations - Positively charged ions in the water (e.g., calcium, magnesium, sodium, ammonium, etc.).Caustic or Caustic Soda - The chemical compound sodium hydroxide (NaOH).Coagulants - Materials added to the water / wastewater or water / wastewater treatment sludge to allow agglomeration of smallparticles into larger particles to facilitate their separation from the water.Coagulation Aids - Materials added to the water / wastewater or water / wastewater treatment sludge after a coagulant(primary coagulant) has been added to increase the speed of floc formulation and the floc size and strength. Polymers (alsocalled polyelectrolytes) are the most commonly used coagulant aids.Coagulation - The term coagulation is applied to the overall process of particle charge neutralization and physical combination(with the aid of chemicals) of small particles into masses sufficiently large to be settled or floated.Colloid - A substance made up of very small, insoluble particles less than one micron in size. These particles are smallenough so that they remain suspended in a liquid without settling to the bottom.Conductivity - The ability of water to conduct electricity due to the presence of ionized material within the solution.Conductivity is expressed in micromhos/cm (or micro Siemens/cm), and is directly proportional to the amount of dissolvedmatter in the water / wastewater. As a rule of thumb, for wastewater streams at pH 7 the Total Dissolved Solids (TDS) of thatstream in ppm (mg/l) can be approximated by multiplying the conductivity in units of micromhos/cm or microSiemens/cm by 0.7.Flash Mix Tank or Rapid Mix Tank - An agitated drum or tank in which chemicals are rapidly mixed with the water /wastewater in order to improve the effectiveness and speed of reaction.Floc - Suspended particles formed by the agglomeration of smaller suspended particles.Flocculation - The term flocculation is applied to the process of particle charge neutralization and physical combination (withthe aid of chemicals) of small particles into masses sufficiently large enough to be settled or floated. The word flocculation isoften interchangeably used with the word coagulation.Flocculation Tank - A process whereby suspended particles and colloidal particles, which cause turbidity and color in water,are combined by physical means (with the aid of chemicals) into masses sufficiently large to be settled or floated.Hardness - The concentration of calcium and magnesium ions in water, expressed in ppm (mg/l) as calcium carbonate(CaCO3) equivalent.Hardness Alkalinity - The concentration of calcium and magnesium bicarbonate and carbonate salts in water, expressed inppm (mg/l) as calcium carbonate (CaCO3) equivalent.Hydroxide Alkalinity - The free hydroxide ions in water, expressed in ppm (mg/l) as calcium carbonate (CaCO3) equivalent.Ion - Electrically charged particle formed when a molecule dissociates into positive and negative particles in water (e.g., saltinto sodium + and chloride - ions).Makeup or Makeup Water - The water required to replace circulating water which is lost by evaporation, drift, blowdown, andleakage. It is expressed in percent of water circulated.




Nutrients - Chemical elements such as nitrogen, potassium, phosphorous, etc., which are essential for bacterial growth inbiological wastewater treatment systems.Once-Through Cooling System - A system in which cooling water passes through heat exchange equipment once and is thendischarged directly, with no recycle or circulation.Polymer or Polyelectrolyte - A polymeric organic compound commonly added to water / wastewater to promote coagulationand flocculation of suspended material. It is also added to water / wastewater treatment sludges to enhance thickening anddewatering. The following are the three basic types and uses of polymers:1. Anionic (negative charge) - generally serve as coagulant aids to inorganic or organic primary coagulants by increasing the

rate of coagulation and the size and roughness of floc particles.2. Cationic (positive charge) - serve as primary coagulant alone or in combination with inorganic coagulants or with anionic or

nonionic polymers. Some cationic polymers with very high molecular weights may also be used as coagulant aids.3. Nonionic (no net charge) - serve as coagulant aids in a manner similar that of both anionic and cationic polymers.Recirculated Cooling System - A system in which water is circulated to coolers in a loop and the heat absorbed from thiscooling operation is dissipated by a cooling tower or some other type of heat exchanger.Recirculation - An undesirable condition in which part of the cooling tower discharge vapor stream is recirculated through thetower resulting in increased inlet air wet bulb temperature.Sludge - The accumulated semi-liquid suspension of settled solids deposited in tanks or basins from raw or treated water /wastewaters. Dissolved-Air Flotation and Induced-Air Flotation floats and Granular-Media Filter backwash are also included inthis definition for the purpose of this Design Practice.Sludge Conditioning - The addition of inorganic or organic chemicals to increase the efficiency of sludge thickening and/ordewatering.Sludge Dewatering - The removal of water from a sludge or slurry, usually by mechanical means, to greater than 10 wt%solids.Sludge Thickening - Thickening is a process which aims to increase the solids content of a dilute slurry by removing some ofthe water content by gravitational or flotation means. Typically, gravity thickeners can produce sludges with 4-6% solids byweight. Flotation thickeners typically conditions sludges to between 4 and 8% solids by weight.Softening - The process of removing calcium and magnesium ions from water.Specific Gravity (SG) - The specific gravity of a liquid is the ratio of the weight of a given volume of the liquid to the weight ofan equal volume of water. Thus the specific gravity of a solution of chemical at 60°/60°F refers to the weight of a given volumeof chemical at 60°F as compared with the weight of an equal volume of water at 60°F.Turbidity - A term referring to the lack of clearness in a water due to the presence of suspended or colloidal matter andexpressed in Nephelometric Turbidity Units (NTU).

BACKGROUNDChemical addition facilities are an integral part of many grassroots water / wastewater treatment process unit designs. Theyare necessary for the proper operation and performance of the facility. However, chemical addition may also be retrofitted onexisting process units to improve the unit's functional performance, decrease its operating cost, or extend its capability toprocess larger than design flow rates of water / wastewater and/or water / wastewater treatment sludges.The designer of the chemical feed systems should provide as much flexibility as possible in the design of the chemical injectionsystem to allow optimum selection of the application point(s) and take advantage of different chemicals offered by vendors.This flexibility is particularly important for coagulant and coagulant aid addition points.Reference 2, Guidelines for Safety Evaluation of Chemical Injection Facilities, should be used when designing or receiving achemical feeding and handling system. The application guide is especially written to facilitate a safety evaluation of vendorprovided chemical injection facilities. The guidelines cover the storage container, injection pump, and injection point.Table 1 provides a summary of the chemicals which are most commonly used in water / wastewater treatment applications.Table 2 provides detailed information such as chemical formulas, available forms, storage considerations, and safetyconsiderations for the commonly used chemicals in Table 1. Figures 1 to 6 illustrate the various types of chemical feedingsystems used in water / wastewater treatment. A water / wastewater analysis (see Table 3) can be very useful in determiningthe required chemical application.





WASTEWATER TREATMENT

COAGULATION / COAGULATION AIDGeneral - Chemical coagulation is accomplished by one or a combination of the following two basic mechanisms:1. Particle Charge Neutralization - Most suspended matter in wastewater has an apparent negative surface charge. This

negative surface charge on the particles creates a net repulsive force between particles, thereby inhibiting agglomerationof the suspended matter. The addition of positively charged metal ions or cationic polymers can neutralize these surfacecharges and allow particle agglomeration either with or without a coagulant aid.

2. Particle Bridging - The addition of metal salts can form metal hydroxides under the proper set of pH and dosageconditions. These metal hydroxides form large sets of molecules that attach themselves to the suspended particles,thereby bridging the gap between particles and drawing them together into a strong floc lattice structure. Polymers canalso be effective particle bridging chemicals.

Particle Charge Neutralization using polymer chemicals is the preferred mechanism for coagulation because it generallyrequires less chemical and produces less sludge than Particle Bridging.Primary Coagulant - Cationic polymers are the preferred primary coagulant for coagulation. In the past, Bentonite,Diatomaceous Earth, and metal salts were commonly used as primary coagulants. Some manufactures provide blendedproducts which contain both a metal salt and a polymer. However, due to improved polymer technology, polymers are nowrecommended for new applications. Cationic polymers have advantages over other primary coagulants as follows:• Easier to store and handle.• Used as neat polymers, eliminating mixed / diluted solution tank.• Produce less sludge (which ultimately must be disposed of).• Resulting sludge contains less water, is less acidic, and can be more easily dewatered.• Performance is less pH dependent.• Do not add to the total dissolved solids concentration.Coagulant Aid - In cases when different types and large doses of primary coagulant fail to produce a satisfactory floc, apolymeric coagulant aid should be added after the primary coagulant. Very high molecular weight (> 1 x 106) polymers like thenonionic polymers and low molecular weight (< 20,000) polymers like the anionic polymers have proven successful and arerecommended coagulant aids.Applications - Chemical coagulation is applied for suspended solids and free oil removal during wastewater treatment toenhance separation of solids and oil from the wastewater, in clarification and thickening, in sludge dewatering, and in metalsremoval.1. Flotation Processes (DP XIX-A2) - Chemical coagulation is almost always required to attain even moderate degree of

free oil and suspended solids removal from flotation processes. By chemically agglomerating the small diameter particles,impingement and attachment of air bubbles on the larger floc particles is enhanced, thereby improving the efficiency of theflotation process. Normally, chemical coagulation will also help increase the concentration of oil and solids in the float fromthese processes.Dissolved Air Flotation (DAF) process units are generally preceded by chemical flocculation equipment (i.e., a flash mixand a flocculation tanks). The primary coagulant is generally added in the flash mix tank. If a coagulant aid is required, itis added in the flocculation tank or injected in the influent line just prior to the flotation unit.Induced Gas Flotation (IGF) process units do not normally have a flash mix or a flocculation tank. The primary coagulantis injected directly into the influent line far enough upstream of the flotation unit to allow complete mixing with thewastewater. If a coagulant aid is required, it is injected in the influent line just prior to the flotation unit. Static or in-linemixers are generally used for direct injection.

2. Filtration Processes (DP XIX-A3) - Use of chemical coagulation, optimized with respect to both chemical type(s),dosage(s), and point(s) of injection, can improve effluent quality, extend the run length of Granular-Media Filtration (GMF)units, and increase the concentration of oil and solids in the backwash. The primary coagulant is injected directly into theinfluent line far enough upstream of the filtration unit to allow complete mixing with the wastewater.

3. Clarification (DP XIX-A4 and XIX-A5) - Primary coagulants, and sometimes coagulant aids, are used to help settle outsuspended material in the clarifier. They also help chemically treat dispersed growth of biological solids. Both the primarycoagulant and coagulant aid are added upstream of the clarifier.

4. Sludge Thickening by Flotation (DP XX-A1) - In sludge thickening by flotation or gravity filtration, cationic polymers arethe preferred primary coagulant. A coagulant aid is not generally required. The cationic polymer is injected directly into




the influent line far enough upstream of the thickener to provide complete mixing with the sludge. It may also be added ina feed mixing tank. However, care should be exercised in controlling the intensity of mixing in this tank to avoid excessiveshearing of the sludge.

5. Sludge Dewatering (DP XX-A3) - For low shear sludge dewatering processes such as belt filter pressing, vacuumfiltration, and centrifugation, the primary coagulant is usually injected in the influent pipe just prior to, or directly into a lowintensity mixing tank which precedes the process unit. In some cases, it is also possible to eliminate the need for a gentlemixing tank by injecting the primary coagulant into the influent line upstream of an in-line mixer, or far enough upstream toallow complete mixing of the chemical with the sludge. If a coagulant aid is required, it is injected immediately before thedewatering process unit.For high shear sludge dewatering processes, such as high-pressure filtration, the primary coagulant is added to the sludgein a batch mixing tank prior to the filter press. Diatomaceous Earth is sometimes useful as a precoat material on thepressure filter cloth. A precoat both enhances the concentrated sludge cake release from the cloth and prevents pluggingof the cloth during the filtration process. Waste FCCU catalyst fines can also be used as a filter cloth precoat material. If aprecoat is used on the filter cloth, it is generally applied directly to the filter cloth in slurry form prior to feeding the sludge tothe filter.

6. Metals Removal - Depending on the metal, chemical coagulation followed by gravity separation, flotation, or filtration canremove undissolved and some dissolved heavy metals which may be chelated or coprecipitated by the chemicals, such asEDTA and Iron salts, respectively. Similarly, a small reduction in both the dissolved and undissolved heavy metals occursby adsorption on biological solids and undissolved heavy metals are removed by incorporation into the biological solidsfloc.The primary coagulant, which forces the precipitation of metals, is typically added in the flash mix tank. If required, acoagulant aid is usually added either in the flocculation tank or in the influent line just prior to the separation unit where themetal precipitate is removed from the wastewater.

Types and Dosages - The types and dosage rates of coagulant / coagulant aid required to provide the best performance forspecific applications cannot be theoretically predicted and must be determined by bench laboratory tests and field trials.Table 4 summarizes the bench scale tests that will help determine the best combination of chemicals and the optimum dosagesfor a particular wastewater. If pilot plant facilities are used to optimize new process unit design parameters, concurrent tests onthese units may also be utilized to determine the optimum chemical type(s) and dosage(s).As a general guide for initial lab tests or as a design guide for grassroots facilities where there is no wastewater available,chemical dosage ranges are as follows:

TREATMENT TYPE POLYMER TYPE TYPICAL DOSAGE RANGEPRIMARY COAGULANT Cationic 1 - 10 ppm (mg/l) as neat polymer

COAGULANT AID Anionic or Nonionic 0.1 - 3 ppm (mg/l) as neat polymer

Design guidelines / parameters for coagulation / coagulation aid / flocculation are as follows:• The chemical feed system for cationic polymers (Figure 4) typically includes a bulk storage tank (temporary semi–bulk

storage tanks may be provided by supplier) and a spared pumping configuration.• The chemical feed system for anionic or nonionic polymers (Figure 3), typically includes a bulk storage tank (temporary

semi–bulk storage tanks may be provided by supplier), a mixing tank, a mixture storage tank, and two spared pumpingconfigurations (one set for the bulk tank and the second for the mixing tank).

• The coagulant / coagulant aid should be injected via dosing pumps. Normally, 2-100% capacity pumps are provided foreach pump configuration. Positive displacement metering pumps are used for rates up to 100 gph (0.1 L/s). Centrifugalpumps with flow control are used for higher rates. As with any pumps or equipment, area classifications should beconsidered in selecting and specifying them.

• The bulk storage tank should provide a minimum inventory of 15 days at the design consumption rate.• The mixing tank and the mixture storage tank for anionic and nonionic polymer feed systems should not exceed 48 hours

of inventory.• The bulk tanks should contain a slow speed, blade type agitator. The intensity of mixing energy supplied depends on the

emulsion tendency, the nature of the solids in the stream, and shearing intensity if in sludge service.• The bulk storage tank should be equipped with a level gage that is visible from the unloading connection.• Dilution water shall be clean condensate or equivalent water quality. Potable water must never be used.1





• A pressure relief valve should be provided downstream of each pump system even if built-in relief valves are provided withthe pumps. The set pressure is to be 10% above the operating pressure at the pump discharge or 10% above the processequipment design pressure, whichever is greater.

• Sizing of the facilities may require consultation with the chemical(s) suppliers. Concentrations and activity of vendorsupplied chemicals can vary and have an effect on storage volumes and pumping rates.

• Commonly used worldwide polymer suppliers are as follows. The company distribution area and internet web address arelisted below.

Company Web Address Distribution AreaAshland Specialty Chemical Company www.ashchem.com North America

Vulcan Chemicals www.vul.com North AmericaBaker Petrolite www.bakerhughes.com/bakerpetrolite International

GEBetz Chemicals www.gebetz.com InternationalONDEO Nalco Chemical Co. www.ondeonalco.com International

US Filter - Stranco www.stranco.com International

** This list is provided as a convenience to the user and is not intended as an endorsement. Other suppliers should alsobe contacted; they may provide unique products unavailable from the suppliers on this list.

NUTRIENT ADDITIONMicroorganisms require nutrients in addition to the primary carbon food source. Macronutrients consist of nitrogen (N) andphosphorus (P). Micronutrients, or trace elements, are also required by microorganisms. The micronutrients (K, Fe, Mg, Ca,Zn, Cu, Co, etc.) are typically found in refinery and petrochemical wastewaters in sufficient concentrations. However, themacronutrients are often insufficient. Because nitrogen and phosphorus are essential for microorganism growth andreproduction, they are also essential for waste degradation.Nitrogen - There are several forms of nitrogen found in wastewater: organic nitrogen, ammonia, nitrate, and nitrite. Ammonianitrogen exists in aqueous solution as either the ammonium ion or ammonia, depending on the pH of the solution.As a rule of thumb:

PPM (mg/L) of Nitrogen required for bio-growth = ppm (mg/l) of BOD5 in the wastewater/20

If supplemental nitrogen is required, there are several sources of nitrogen that can be used. The recommended nitrogensource is ammonium salts due to their easier handling and mild corrosivity. The advantages and disadvantages for the mostcommon sources of nitrogen are as follows:

NITROGEN SOURCE ADVANTAGES DISADVANTAGES

Ammonia 2

(NH3)• Requires small dosages due to high

strength• Gas toxic at concentrations over 100 ppm in

air• Gives off pungent, irritating odor• Corrosive• Safety equipment required

Ammonium Hydroxide 2(NH4OH)

• Available in bulk liquid • Gives off pungent, irritating odor• Corrosive• Safety equipment required

Ammonium Salts2

e.g., (NH4)2SO4• Relatively easy to handle

• Only mildly corrosive

• Tends to cake• Safety equipment required

Urea2

(NH2CONH2)• Relatively easy to handle • Corrosive

➧1: Unless isolation and backflow concerns are addressed to meet local and/or minimum ExxonMobil Requirements.2: Refer to Table 2 for Safety Considerations




Design guidelines / parameters for ammonium sulfate feed systems are described below. The preferred method of feedingammonium salts is to prepare a bulk solution and follow the recommended procedures for bulk liquid chemicals.• The chemical feed system for ammonium salts (Figure 1) typically includes a bulk storage tank and a spared pumping

configuration.• The ammonium salt solution should be injected via dosing pumps. Normally, 2-100% capacity pumps are provided.

Positive displacement metering pumps are used for rates up to 100 gph (0.1 L/s). Centrifugal pumps with flow control areused for higher rates.

• The bulk storage tank should provide a minimum inventory of 15 days at the design consumption rate.• The bulk storage tank should contain an agitator.• The bulk storage tank should be equipped with a level gage that is visible from the unloading connection.

• Dilution water shall be clean condensate or equivalent water quality. Potable water must never be used.1

• A pressure relief valve shall be provided downstream of each pump system even if built–in relief valves are provided withthe pumps. The set pressure is to be 10% above the operating pressure at the pump discharge or 10% above the processequipment design pressure, whichever is greater.

• Protective facilities, e.g., safety shower and eye wash, should be within 50 ft of the injection facilities (GP 3-2-6).Phosphorus - The usual forms of phosphorous found in aqueous solutions include orthophosphate (PO4–3, HPO4–2, H2PO4–1,H3PO4), polyphosphate (molecules with two or more phosphorus atoms), and organic phosphate.As a rule of thumb:

PPM (mg/L) of Phosphorus required for bio-growth = ppm (mg/l) of BOD5 in the wastewater/100

If an appropriate amount of phosphorus for bio–growth is not found in the wastewater for biotreatment, phosphorus may beadded. Several sources of phosphorus are available, however typically phosphoric acid (H3PO4) is used. The phosphoric acidis a low strength acid and is added in relatively low dosages, hence there is no significant effect on the wastewater pH. Theadvantages and disadvantages for the most common sources of phosphorus are as follows:

PHOSPHORUS SOURCE ADVANTAGES DISADVANTAGES

Phosphoric Acid (H3PO4) 2 • Available in bulk liquid

• Easy to pump and meter flow

• Corrosive

• Safety Equipment RequiredPhosphate2 • Neutral Solution • Low strength solution due to solubility

limitations

Design guidelines / parameters for phosphoric acid feed systems are as follows:• The chemical feed system for phosphoric acid addition (Figure 1) typically includes a bulk storage tank and a spared

pumping configuration.• The phosphoric acid should be injected via dosing pumps. Normally, 2-100% capacity pumps are provided. Positive

displacement metering pumps are used for rates up to 100 gph (0.1 L/s).• The bulk storage tank should provide a minimum inventory of 15 days at the design consumption rate.• The bulk storage tank should be equipped with a level gage that is visible from the unloading connection.• Dilution water, if required, shall be clean condensate or equivalent water quality. Potable water must never be used.1

• A pressure relief valve shall be provided downstream of each pump system even if built-in relief valves are provided withthe pumps. The set pressure is to be 10% above the operating pressure at the pump discharge or 10% above the processequipment design pressure, whichever is greater.

• Protective facilities, e.g., safety shower and eye wash, shall be within 50 ft of the injection facilities (GP 3-2-6).

pH ADJUSTMENTSGeneral - Refineries and petrochemical plant's wastewater often contain acidic or alkaline materials that may require pHadjustment prior to discharge to receiving waters, or prior to chemical or biological treatment.

➧1: Unless isolation and backflow concerns are addressed to meet local and/or minimum ExxonMobil Requirements.2: Refer to Table 2 for Safety Considerations





Acids - Any strong acid can be used effectively to neutralize alkaline wastes, but cost considerations usually limit the choice tosulfuric or hydrochloric acid. The reaction rates are practically instantaneous. Some advantages and disadvantages for thesetwo recommended acids are:

ACID ADVANTAGES DISADVANTAGESSulfuric Normally Lower Cost Corrosive

Dangerous to handleMay form CaSO4 precipitation in the presence ofcalcium

Hydrochloric No Heated DilutionMost effective

CorrosiveDangerous to handleGives off pungent irritating odorVolatile

Properties of commercially available forms are as follows:

WT OF CHEMICAL PERVOLUME OF SOLUTION

SOLUTION TYPEWT% OF

CHEMICAL lb/gal g/lSG OF

SOLUTION BAUMÉ

93 14.19 1700 1.8279 65.7Sulfuric Acid(H2SO4) 98 15.02 1799 1.8361 66.0

32 3.096 371.0 1.1593 19.9HydrochloricAcid (HCl) 36 3.542 424.4 1.1789 22.0

Bases - Sodium Hydroxide, also called caustic soda, is the most commonly used base due to its availability as an aqueoussolution. The advantages of liquid caustic (< 50 wt% strength) over other bases are:• It is easier to unload (tank trucks) and handle.• Delivery cost is lower than any other dry bases.The commercially available strengths for caustic are as follows:

WT OF CHEMICAL PERVOLUME OF SOLUTION

SOLUTION TYPEWT% OF

CHEMICAL* lb/gal g/lSG OF

SOLUTION BAUMÉ

20-25 2.035 243.8 1.2191 26.1Sodium Hydroxide(NaOH) 50 6.364 762.7 1.5253 49.9

Note:

*For caustic with strength greater than 50%, special care must be provided. Consult EMRE's Water and Waste Section.Applications - Wastewater typically requires pH adjustment in the following wastewater treatment areas.1. Prior to Secondary Oil and Suspended Solids Separation - The primary purpose of adjusting the pH at this point is to

assure that the proper pH range is maintained for optimum performance of inorganic coagulants and coagulant aids.2. Biological Treatment - Aerobic biological treatment systems operate effectively within a relatively narrow pH window.

The pH in the biological reactor should be controlled between 6.5 and 8.5 (optimum range is 7 to 8). Therefore, pH controlis required to prevent upsets of the biological treatment system.Aerobic treatment under non-nitrifying conditions uses H+ ions tending to increase pH. The increase in pH is only slightlybecause alkalinity is also produced.Biological nitrification of ammonia consumes about 7 pounds of alkalinity for every pound of ammonia (expressed asCaCO3) which is oxidized to nitrate. If the influent wastewater to the biological treatment plant does not have sufficient




alkalinity, the pH can be significantly lowered and the biological process upset by alkalinity consumption throughnitrification. It is recommended to control the pH of the basin, which is easier to control than the feed.Anaerobic biological decomposition of organic matter may either produce or consume alkalinity depending on the organiccomposition of the feed. The alkalinity in the anaerobic biological treatment system should be maintained at a minimum of1000 ppm (mg/l) as CaCO3 equivalent to avoid process upsets which can be caused by extreme pHs (optimum pH rangeis 6.5 to 7.5).

3. Prior to Final Discharge - Generally, if the final discharge of the wastewater is preceded by biological treatment,additional pH adjustment is not necessary. Otherwise, it may be necessary to adjust the pH of the final discharge tocomply with local regulations.

Dosages - The dosage rates for acids / bases have been traditionally predicted by bench-scale tests. More recently, computermodeling via the Environmental Simulation Program (ESP) has been successfully used in ExxonMobil to predict dosagerequirements for acids and bases. This model is available through EMRE's Water & Waste Section. Pilot plant facilities canalso be used to determine the optimum chemical dosages in certain cases.Design guidelines / parameters for pH adjustment chemical feeders are as follows:• The chemical feed system for liquid acid / base (Figure 1) typically includes a bulk storage tank (temporary storage tanks

may be provided by supplier) and a spared pumping configuration.• The acid / base should be injected via dosing pumps. Normally, 2-100% capacity pumps are provided. Positive

displacement metering pumps are used for rates up to 100 gph (0.1 L/s). Centrifugal pumps with flow control are used forhigher rates.

• Whether fixed or portable, the bulk storage tank should provide a minimum inventory of 15 days at the design consumptionrate.

• The fixed bulk storage tank should be equipped with a level gage that is visible from the unloading connection.• Dilution water, if required, shall be clean condensate or equivalent water quality. Potable water must never be used.1


• Protective facilities, e.g., safety shower and eye wash, shall be provided within 50 ft of the injection facilities (GP 3-2-6).

• A feedback / feedforward control loop is recommended to compensate for the inherent short retention time of in–pipeinjection.

• Use of feedback, feedforward, or both for pH control will depend on the application and control band. (Consult withEMRE's Environmental Section on specific applications)

• A pH analyzer with high and low alarm is generally provided to control the amount of acid / base feed.

OXIDANTSApplications - Oxidants like hydrogen peroxide have been used to oxidize small quantities of sulfide, phenols, and otherorganics in wastewater, at their source such as tank bottoms, desalters, or in pre-treated wastewaters. Hydrogen peroxide isusually added in a flash mix tank or a junction of a flow splitter box with a high level of mixing, or a static mixer may need to beemployed in a line.Hydrogen peroxide has also been used to control severe cases of filamentous bacteria or bulking (poor settling) of biologicalsolids in activated sludge clarifiers. The injection point is the biological sludge recycle line.The use of hypochlorite or other halogenated compounds for oxidation is generally recommended only for sulfide control infairly clean or low organic contamination wastewaters (such as stagnant pond or lagoon waters). The use on organic ladenwastewaters, expecially those containing phenolic compounds, could potentially form halogenated organics, and therefore isnot recommended. Use of hypochlorite for biological sludge bulking control should only be considered after use of peroxidehas been tried. Hypochlorite use needs to be carefully controlled to avoid killing off desirable microbes in the activated sludge.Dosage - The dosage rate of hydrogen peroxide generally ranges between 50 to 200 ppm (mg/l) for controlling biosolidsbulking. The dosage should be started at a low level (50 wppm) and increased gradually in steps, until the bulking is controlled.For oxidation of sulfide and phenols contamination, a guideline of 3 wppm of H2O2 (100% basis) per 1 wppm of sulfide, and 4wppm of H2O2 per 1 wppm of phenols is typical, but temperature, pH and reaction time need to be considered, especially fororganic contaminants such as phenol.

1: Unless isolation and backflow concerns are addressed to meet local and/or minimum ExxonMobil Requirements.





Design guidelines / parameters on the use of hydrogen peroxide are given below. Refer to DP-XIX-A11 on ChemicalOxidation for more details on use of hydrogen peroxide for treatment.• The chemical feed system for hydrogen peroxide (Figure 1) typically includes a bulk storage tank (permanent or

temporary) and a spared pumping configuration.• The oxidant should be injected via dosing pumps. Normally, 2-100% capacity pumps are provided. Positive displacement

metering pumps are used for rates up to 100 gph (0.1 L/s). Centrifugal pumps with flow control are used for higher rates.• For permanent facility, the bulk storage tank should provide a minimum inventory of 15 days at the design consumption

rate.• The bulk storage tank should be equipped with a level gage that is visible from the unloading connection.• Dilution water, if required, shall be clean condensate or equivalent water quality.


• Protective facilities, e.g., safety shower and eye wash, shall be provided within 50 ft of the injection facilities. (GP 3-2-6).➧ • Peroxides are strong oxidants and should not be added directly to very oily waters or in plant sewer systems that can dry

out. Consult plant safety personnel and supply vendors for safe application. Permanent systems will require a peroxideaddition pump cut off , when there is no flow of wastewater in the lines being treated . Usuallly, commercial grades of 35%H2O2 are preferred to ensure there is enough dilution water, and a minimal temperature rise due to the exothermicreaction of the peroxide with the contamination.

• Due to oxidative nature of chemicals, materials of construction will require review.

FOAM CONTROLThe most typical application of defoamers in wastewater treatment is in biological treatment units. Usually, defoamers are onlyused on a sporadic basis to eliminate serious foaming problems. Defoamer type and dosage may be selected by placinginfluent water, or water from the biological treatment in a 2-L graduated cylinder which is moderately aerated with a sparger.The effectiveness of the chemical type and dosage in reducing the tendency of the water to foam is evaluated visually.Typically silicone based antifoams are used due to their low toxicity.Design guidelines / parameters on the use of defoamers are given below.• Defoamers are most commonly sprayed on the surface of the wastewater in the reactor basin rather than injected directly

into the bulk wastewater. Spray application may be performed using a portable tank and spray system or a permanentlyinstalled spray system.

• For small volume, liquid defoamers, gravity feed directly from the drum using a needle valve.• For large volume feed, more accurate dose control, and/or high viscosity defoamers, metering pumps are recommended.• Prepare the defoamer as 5% solutions for feeding convenience. The solution should be continuously agitated to maintain

a homogeneous solution.• Because the products are non-corrosive, metal or plastic feed lines can be used. Avoid use of rubber gaskets or hoses

which may dissolve in prolonged contact with defoamers.• The best time to apply a defoamer is shortly before the foam becomes troublesome, such as when the foam layer is

building in a biox basin/tank or clarifier, thus allowing for adequate mixing and reaction time. Although defoamers cancollapse foam, they are more effective when applied before it develops.

COOLING WATER TREATMENTBIOLOGICAL CONTROLThe operating conditions in recirculated cooling water are ideal for the growth of biological matter. To control the biologicalactivities, a biocide chemical is added to the water treatment program. Oxidizing biocides such as chlorine, sodiumhypochlorite, chlorine dioxide, or bromine-associated compounds are most commonly used with good results.For either once-through or recirculation system, facilities should be provided for feeding the biocide into the back of the coolingtower basin. If chlorine is used, it must be present in the cooling water as free residual to be effective.




Chlorine - For recirculating cooling systems, the design capacity of the chlorine feeder shall be based on achieving a 0.1-0.3wppm (mg/l) free chlorine residual in the recirculating water flow or a minimum dosage of 7 wppm (mg/l) at maximum designcooling water flow rate (see DG 11-3-1).For once-through cooling water systems, shock chlorination once a day is normally practical and the chlorinator design shouldbe based on achieving a chlorine residual of 1 wppm (mg/l) in the effluent for 1 hour. The chlorine required by the organics andother reducing agents in the water must be satisfied before any residual chlorine will appear in the effluent. In the absence ofwater data, the chlorination system design capacity should be based on 10 wppm (mg/l) minimum instantaneous dosage formaximum cooling water flow.Chlorine may be fed either as gaseous chlorine (100% Cl2) or the commercial liquid sodium hypochlorite (12.4 wt% Cl2). Liquidhypochlorite is becoming popular due to the higher costs associated with precautions, equipment, and procedures required tominimize the risks associated with handling gaseous chlorine. The hypochlorite solution is fed using a metering pump whichshould be sized to feed an equivalent of 15 ppm 100% Cl2 if field data is lacking (refer to DG 11-6-2). Spills or overflow fromthe sodium hypochlorite storage tank may be sent to the cooling tower basin.The use of gaseous chlorination is being reduced but may still be appropriate in some locations subject to local approval. Thegas from either commercial cylinders or an evaporator is dissolved in a water slip stream by means of an eductor. This resultsin a chlorine solution strength of approximately 0.1 wt%. This solution should be evenly distributed below the water surface bymeans of a lateral pipe arrangement at the rear of the cooling tower basin, opposite the cooling water pumps. Gaseouschlorine will tend to lower the system pH due to the HCl byproduct.Design guidelines / parameters on the use of gas chlorinators are given below. It is also recommended that the safetyguidelines published by the Manufacturing Chemists Association and the Chlorine Institute be followed.• Dilution water for the chlorinator must not be less than 50°F (10°C), or ice formation may cause plugging problems.• Continuous rates of chlorine gas withdrawal should not exceed 400 pounds (180 kg) per 24 hours from each one ton

cylinder, at room temperature (70°F or 21°C). This rate may be exceeded (up to 50%) for periods not exceeding 2 hours.Rule of thumb is not to design for more than 4 cylinders operating in parallel. When the feed rate exceeds 3000 pounds(1360 kg) per day the liquid chlorine should be fed to an evaporator upstream of the chlorinator (see DP XXVII).

• If the ambient temperature can be expected to be below 50°F (10°C) for extended periods, a building should be providedfor the chlorinator and cylinders.

• Weighing scales should be provided to determine when shipping containers should be replaced and to verify chlorine feedrates.

• Analyzers to measure the free chlorine residual in the circulated cooling water should be provided.• Chlorine leak detectors and a catch basin for major spills shall be provided.Dichloroisocyanuric Acid Salts, Mixture (Sodium Bromide) - This chemical shall only be fed with a Calgon “Towerbrom�"feeder or equivalent. Calgon Towerbrom feeder is a flow through feeder where the chemical is dosed into the water. Mix onlywith water and use clean dry utensils. Do not add this product to any dispensing device containing remnants of anyother product (like hydantoin-based bromine products (BCDMH) or other organic material). Such misuse may cause aviolent reaction leading to fire or explosion.Bromo chloro dimethylhydantoin - Solid flow through feeder as shown in Figure 5 should be used. Fresh makeup water,e.g., well or river, which cannot be contaminated with hydrocarbon should be used as dilution water. Recycled cooling towerslipstream should not be used. Bromo chloro treaters can exhibit high temperatures due to oxidation of hydrocarbons (or anyother oxidizable substance) when there is no flow through the vessel. Therefore, use of fresh water is the preferred choiceregardless of design or chemical. Appropriate training should be provided for all personnel using bromicide.

CORROSION CONTROLTo reduce corrosion to an acceptable level, chemical corrosion inhibitors which form protective films on heat transfer surfacesare the most effective protection. Inhibiting corrosion is accomplished by phosphates, zinc, nitrites, and molybdate salts. Theuse of chromate, which is a reliable corrosion inhibitor, is prohibited by environmental constraints. Nitrite is not practical for usein an open system due to atmospheric oxygen converting the nitrite to nitrate.The corrosion inhibitors most frequently used in ExxonMobil recirculating cooling water systems are shown in descendingorder of preference, provided their use meets all environmental requirements:1. Stabilized Phosphate (Ortho / Polyphosphate) or Alkaline Phosphate.2. Alkaline or Zinc Alkaline Phosphate.3. All Polymers (Organic (Polymer) Salts).Design guidelines / parameters for corrosion inhibitors design are given below. The following guides in sizing equipment willallow the use of any vendor proprietary products when final selection by the owner is made. See Report No. EE.102E.78,





Cooling Tower Water Treatment Guidelines, and Report EE.34E.86, Environmentally - Acceptable Cooling Water Treatments,for detailed discussion of acceptable commercial chemicals.

• Generally, two chemical feeders are provided.• If the water treatment program to be used is known, design for the chemical rates specified by the vendor or discipline

specialist. Otherwise, design for 100 wppm (mg/l) of each commercial liquid product in the recirculated cooling water. Thedesign feed rate should be based on the design total blowdown flow (both uncontrolled and controlled) since this is wherethe product is lost. For 100 wppm (mg/l) concentration, the chemical rates will be as follows:– Gallons/Hour Chemical = 0.006 x Blowdown (gpm)– Liters/Hour Chemical = 0.36 x Blowdown (L/s)

• The design capacity of the metering pump should be two times this calculated number. Normally 2-100% design capacitypumps are provided. Positive displacement pumps are used for rates up to 100 gph (0.1 L/s).

• Specifications for chemical feeders may be found in DG 11-6-2 and Tables 1 and 2.• A final check should be made with the owner and the discipline specialists as to the treatment program selected, and if

there is a need for an additional chemical feeder.

pH ADJUSTMENTThe cooling water treatment program selected and the site water quality will determine the need for pH adjustment. Computermodeling using the Environmental Simulation Program (ESP) can assist in predicting acid requirements. This model isavailable from EMRE's Water and Waste Section. Routine monitoring of pH of the water in an existing cooling unit willestablish the guidelines for periodic adjustment of the chemical dosage to the unit.Design guidelines / parameters to pH adjustment design for cooling towers are given below. In addition, follow the guidelinesunder pH Adjustment for Wastewater Treatment.• In cases where a controlled pH control program is being used, the pH of the recirculated cooling water should be controlled

in accordance with the program requirements. Normally, acid addition is required to accomplish this. This is due to freecarbon dioxide being stripped across the cooling tower to approximately 5 ppm (mg/l). For example, if the alkalinity mustbe controlled to between 25 and 50 ppm (mg/l) for a pH of 7.0 to 7.5, the volume of 98% sulfuric acid (66°Bé) required totreat the makeup water is calculated using the following equation:Note: 93% sulfuric acid should be used if ambient temperatures will be less than 35°F (2°C).

Gal/h of 100% (66°Bé) H2SO4 = 3.26 x 10–5 x (Alkalinity in Makeup Water (Customary)as wppm CaCO3) x (Makeup Rate in gpm)

or

Kg/h of 100% (66° Bé) H2SO4 = 7.93 x 10–3 x (Alkalinity in Makeup Water (Metric)as wppm CaCO3) x (Makeup Rate in L/s)

• Hydrochloric acid may also be used for pH control. The gallons per hour of 20° Bé hydrochloric acid required are 3.6 timesthe amount of 66° Bé sulfuric acid. In metric units, the weight of 32% (20° Bé) hydrochloric acid required is 2.27 times theweight of 100% (66° Bé) sulfuric acid.

• The metering pump should be designed for a maximum feed rate of two times the design feed rate. A proper mesh-screenstrainer is required on the pump suction piping to minimize plugging. Normally, 2-100% capacity pumps are provided.Positive displacement metering pumps are used for rates up to 100 gph (0.1 L/s). Centrifugal pumps with flow control areused for higher rates.

• Specifications for chemical feeders for the cooling towers may be found in DG 11-6-2.• A pH analyzer with high and low alarm is provided to control the amount of acid feed. The acid should be added to the

cooling tower makeup water (Figure 6).• Spills or overflows from the sulfuric acid tank should be contained.




BOILER FEED WATER TREATMENTChemical treatment of the boiler water protects the steam generating system from the impurities remaining in the BoilerFeedwater (BFW). The BFW which is pumped from the deaerator is free of oxygen and carbon dioxide which may have beenpresent in the make-up water or condensate streams. Types and amounts of other impurities remaining in the BFW willdepend on the method of make-up water treatment (which is usually a function of steam quality requirements) and thesource(s) of return condensate streams.Reliable and separate feed systems are required for:1. Oxygen Scavenging2. Condensate Dosing3. Internal Boiler Water Quality ControlDesign guidelines / parameters for boiler water treatment chemical feed system are given below.• Each system typically includes a storage tank and a spared pumping configuration.• Chemicals storage should provide a minimum inventory of 24 hours at the design consumption rate.

• Provide two metering pumps (normal plus spare) each for the oxygen scavenger and the condensate dosing facilities. Thisis based on a single deaerator system. For multiple deaerators, additional dedicated systems should be provided.

• Boiler water chemicals injection shall be via dedicated metering pumps for each boiler. A common spare pump, capable ofserving any boiler shall also be provided.

• Sizing of the facilities may require consultation with the chemical(s) supplier(s). Concentration and activity of vendorsupplied chemicals can vary and have an effect on storage volumes and pumping rates.

CONTROL AND MONITORINGControl strategies for maintaining proper chemical dosages from the feeding systems generally fall into the following twocategories:• Feedback control.• Feedforward control.Feedback control adjusts the dosage based on a process control measurement downstream of the chemical addition point.Feedforward control adjusts the dosage based on a process control measurement upstream of the addition point.If the water / wastewater or sludge flowrate is very constant, the chemical pumping rate may be manually set after each test toprovide the proper dosage. If the water / wastewater or sludge flowrate varies significantly, the dosing pump can be controlledby either a feedback or a feedforward control system to provide a chemical flowrate which is proportional to the flowrate,thereby maintaining the dosage established by the manual test.The installation of automatic controls should be considered for all water / wastewater treating systems, because the annual costof chemicals can be very high. Automatic controllers are available which continuously monitor the condition of the water /wastewater and automatically supplement necessary chemicals to keep the water / wastewater within set limits. The use oftest exchangers and corrosion coupons are also useful in monitoring the effectiveness of the water treatment program.Complete systems may be available through cooling water treatment program vendor as a lease or purchase.Manual control systems may be used in locations that have adequate technical personnel to perform routine water / wastewateranalyses and to modify chemical treatment necessitated by sudden variations in water / wastewater composition, processcontamination, etc.

CHEMICAL PREPARATION AND HANDLINGSpecific requirements for chemical preparation and handling can be found in DGs 11-6-1, 11-6-2, and 11-6-3. Also see ReportEE.92E.94 for additional design practices for chemical injection systems. General considerations for chemical preparation andhandling, methods of chemical receipt, and a summary of information on the safety considerations for handling specificchemicals are provided in Table 2. Selection of chemical storage and delivery systems should consider the following:• Shelf life of chemical.• Hygroscopic tendency of chemical.• Quantity of chemical used.• Safety.





• Economics.Bulk Liquid - This is the preferred method of receipt, because the chemical can be distributed as is with no preparationrequired.In some areas, semi-bulk liquid chemicals will be available in returnable liquid containers. Where this is the case, the followingshould be provided:1. Storage area for a reserve supply of full containers and for holdup of empty containers prior to return. The amount of

holdup will be dependent on the location of the supplier, delivery frequency, and regularity of deliveries. Sufficient holdupshould be provided to reduce the chance of running out of chemical to essentially zero. The storage area may have to besheltered and heated depending on the location and the chemical properties.

2. Provide equipment to off load and handle the full and empty containers if this equipment is not available in the plant.3. Provide an access road for truck deliveries.4. Protective facilities, e.g., safety shower and eye wash, shall be provided within 50 ft of the injection facilities. (GP 3-2-6).In other cases, bulk liquids may be available as truck delivered parcels. In this case the following should be provided:1. 15-day storage (outside). Heating may be required, depending on the properties of the chemical.2. A compressed air supply at 30 psig (210 kPa) for unloading trucks.3. An access road for tank truck deliveries.4. Hose connections to storage tanks.5. A gauge glass or local indicator for tank level plus remote level indication.6. An overflow line on tanks, with a connection to the chemical sewer, if available.7. A dessicator in the vent line or vent routed to a scrubber if using sulfuric / hydrochloric acid tank.8. Protective facilities, e.g., safety shower and eye wash, shall be provided within 50 ft of the injection facilities. (GP 3-2-6).Liquid Chlorine Gas - Refer to Report EE.102E.78, Cooling Tower Water Treatment Guidelines, for information on chlorinehandling and chlorinator operation. A copy of the safety guidelines published by the Manufacturing Chemists Association andChlorine Institute should be available for each plant using a gas chlorinator.

DRY FEED SYSTEMSDry chemical feeders are selected over wet feeders for handling large volume requirements of chemicals available in dry formand in bulk. Bulk dry is the preferred method of receiving dry chemicals. Generally about 30 days of storage is provided.For design of a dry feeder system, there are several variables to consider to make sure that performance is consistent andreliable:1. The characteristics of the chemical, including:

a. Method of storage and transfer from inventory.b. Tendency to cake or bridge, requiring protection from moisture, and vibrators or similar accessory devices to promote

material flow.c. Angle of repose, for proper design of hopper and chutes.d. Particle size distribution, so that dusty materials can be confined, meet safety and work exposure guidelines, and kept

from damaging electric devices.2. The design of the silo, chutes, and hoppers to prevent size segregation and variability in density of the material entering

the feed device.3. The operation environment of the feeder, such as ranges of temperature and humidity, and dust loading in the air.4. Materials of construction.5. Safety.6. Air emission control.When usage is less than about 500 lb/day (225 kg/day), non-bulk receipt may be more economical. For non-bulk drychemicals, consideration must be given to whether storage should be inside or outside depending on the quantity of chemical,hygroscopic nature of the chemical, chemical stability, and the prevailing weather conditions at the facility location. In addition,a safe and efficient method for transferring the dry material from non-bulk storage to bulk storage or a day tank must beprovided.If the dry chemical is highly soluble in water, the preferred method of chemical feeding is to prepare bulk or day quantities ofsolution and use the same feeding system which is recommended above for liquid chemicals (Figure 1). Where the drychemical is not very soluble, use a dry volumetric chemical feeder system (Figure 2) or solid feeders (Figure 5).




The dry chemical in the volumetric feeders is stored in a hopper which is then fed by gravity into the feeder mechanism. Thedevice for displacing the chemical at a controlled rate for the feed bin to the reservoir, or solution tank, may be:1. A traveling belt, with some type of gate to control the depth and width of the band of chemical leaving the spout.2. A screw or auger, turning on its axis in a tube.3. A rotating table, or disk, directly below the hopper spout, with an adjustable doctor blade to deflect a controlled volume of

chemical from the table into a receiver.4. A rotating “paddle wheel" lock valve, similar in some respects to the liquid gear pump, delivering the measured volume

contained in each compartment onto a conveyor belt as the lock valve slowly revolves.Each of these devices can deliver chemical at a rate proportional to the flow of water / wastewater to be treated by using a flowmeter signal either directly - to control belt speed, for example - or indirectly, through a timer.Drums or Bags - Chemical handling facilities should be designed for operation by a single person. A fork lift should beavailable for moving chemical containers.1. Outside Storage requires the following:

• Some protection for chemicals and operators.• Cold treated soft water (less than 100°F or 38°C) for dilution of chemicals. Treated soft water should be piped into the

area where chemicals are mixed. For cooling tower services, except salt water cooling systems, use the cooling watermakeup for dilution.

2. Inside Storage - When the ambient temperature is below 55°F (13°C) for more than 48 consecutive hours, a heated andlighted building is required. The building should contain the following:• Monorail or hoist to move chemicals.• Eductor or feed screw for dry chemicals which are packaged in fiber drums.

DRY MATERIALS (IN BAGS)1. For quantities of less than 1000 lb/day (450 kg/day), use an eductor or feed screw.2. For quantities greater than 1000 lb/day (450 kg/day), provide a variable speed conveyor, automatic bag breaker and

automatic pneumatic loading into silos. Each silo must be provided with high and low-level indicators, isolation valves, andchutes for transferring chemical by gravity to the dry chemical feeder located under the silo. Electric rappers andcompressed air should be provided to keep the dry chemical flowing freely through the chutes.





➧ TABLE 1 SUMMARY OF TYPICAL CHEMICAL APPLICATIONS

CHEMICAL

Silic

aC

ontr

ol

Bio

cide

Coa

gula

tion

Coa

gula

tion

Aid

Con

trol

of

Bio

logi

cal

Solid

s

Sulfi

deR

emov

al

Cor

rosi

onC

ontr

ol

Foam

Con

trol

Met

als

Rem

oval

Nut

rient

Add

ition

Oxy

gen

Scav

engi

ng

pHA

djus

tmen

t

Scal

e/H

ardn

ess

Con

trol

Slud

geC

ondi

tioni

ng

Org

anic

Con

ditio

ning

/Rem

oval

Aluminum Sulfate X X X

Ammonia X X

Ammonium Hydroxide X

Ammonium Sulfate X

Biocides (non-oxidizing) X

Boiler Polymer Treatment X

Brine X

Bromo Chloro Dimethylhydantoin X

Calcium Hydroxide X X X X X X

Calcium Oxide X X X X X X

Chlorine X

Clay/Bentonite X X

Cyclohexylamine X

Defoamer X

Deformer (organic/silica based) X

Diatomaceous Earth X X

Dichloroisocyanuric Acid Salts X

Dispersants X

Ethylenediamine TetraaceticAcid

X X X

Ferric Chloride X X X

Ferric Sulfate X X X

Ferrous Chloride X X X X

Ferrous Sulfate X X X X

Hydrazine X

Hydrochloric Acid X X

Hydrogen Peroxide X X X X

Hydroxylamines X X

Magnesium Oxide X X

Morpholine X

Nitrilotriacetic Acid X X X

Octadecylamine X

Phosphoric Acid X X X X

Polyaluminum Chloride X

Polyelectrolytes X X X X1 X

Powder Activated Carbon X X X X

Sodium Aluminate X X X

Sodium Bromide X




CHEMICAL

Silic

aC

ontr

ol

Bio

cide

Coa

gula

tion

Coa

gula

tion

Aid

Con

trol

of

Bio

logi

cal

Solid

s

Sulfi

deR

emov

al

Cor

rosi

onC

ontr

ol

Foam

Con

trol

Met

als

Rem

oval

Nut

rient

Add

ition

Oxy

gen

Scav

engi

ng

pHA

djus

tmen

t

Scal

e/H

ardn

ess

Con

trol

Slud

geC

ondi

tioni

ng

Org

anic

Con

ditio

ning

/Rem

oval

Sodium Carbonate X X X X

Sodium Hydroxide X X

Sodium Hypochlorite X

Sodium Metaphosphate X X X

Sodium Phosphate X X

Sodium Sulfite X

Sulfuric Acid X X

Urea X

Volatile Oxygen Scavenger X

1 : Special Polymers





➧ Table 2 Properties and Handling Considerations for Commonly Used Chemicals(1)

CHEMICALSNAME

[TRADE NAME]FORMULACAS #(2)

SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER

STORAGECONSIDERATIONS

CHARACTERISTICS,HANDLING, &

SAFETYCONSIDERATIONS

FEEDSYSTEM

FIG #

Aluminum Sulfate(hydrate)[Alum]

Al2(SO4)3 • 14H2O (dry)

Al2(SO4)3 • 49.6H2O (liquid)10043-01-3

20% Al2(SO4)3 Dry: off whitepowder, cake15 to 17% Al2O3Liquid17% Al2O3

Bags, barrels,drums, bulk (railcar or truckload)Bulk (rail car ortruckload)

• Bulk liquid is preferred:20 wt% as Al2(SO4)3.

• Dry: if adequate liquidstorage is not possible orpractical. Maximumstorage tanks shouldhave dust collectors andminimum hopper slope of60°.

• Keep in dry storage.

Dry: Hygroscopic, cakesin high humidity, solubleacidic, mildly corrosive ifwet.Liquid: Astringent,irritates eyes, nose,mucous membrane, andskin. Use protectiveclothing/gloves and eyeprotection. Avoidinhalation of aluminumsulfate dust or vapors.

1 forliquids2 for dry

Ammonia(anhydrous)NH37664-41-7

99 to 100%NH3

Liquefied gas:99 to 100% NH3

Cylinders, tankcars, truck

• Bulk liquid. Light green or light brownliquid, freezing pointapproximately 5°F. Givesoff pungent, irritatingodor. Use protectiveclothing/gloves and eyeprotection.

1

AmmoniumHydroxide[Ammonia Water]NH4OH1336-21-6

20%NH4OH

Liquid:29.4% NH3

Carboy, drums,tank trucks, railcars

• Bulk liquid. Store ina cool, dry,ventilated area..Protect from directsunlight.

Strongly alkaline clearsolution. Causes burnsto skin, irritant to eyes,nose, lung. Corrosive.

1

AmmoniumSulfate(NH4)2SO47783-20-2

25%NH3

Crystal Bags, drums,bulk

• Keep in cool, dry storage. White to brown acidic,soluble, hydroscopiccrystals, tends to cake.Mildly corrosive. Irritantto eyes, skin, andrespiratory tract.

1

Bromo chloroDimethyl-hydantoinC5H6Br ClN2O2

126-06-7

As required Tablet orgranular

Bags, Pails • Store dry in the originalcontainer. Keepcontainer tightly closedwhen not in use. Store incool, dry, well-ventilatedarea away from heat andopen flames. Keepcontainer off wet floors.

Severe eye irritant, canburn skin. Use protectiveclothing/gloves and eyeprotection.Highly exothermic.

5

CalciumHydroxide9

[Hydrated Lime]Ca(OH)21305-62-0

5% Slurry Pre–mixed slurryor powder 93%Ca(OH)2

Bags, barrels,bulk (rail car ortruckload)

• Bulk liquid is preferred:store as an on-siteprepared slurrycontaining 5 wt%Ca(OH)2.

• Dry: if adequate liquidstorage is not possible orpractical, store in bags ordrums or in bulk tank withhopper agitation.

Irritant of eyes, mucousmembrane, and skin.Use protective clothing/gloves and eyeprotection. Avoidinhalation of calciumhydroxide dust or vapors.





TABLE 2 (Cont.)PROPERTIES AND HANDLING CONSIDERATIONS FOR COMMONLY USED CHEMICALS(1)

CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

Calcium Oxide[Quick lime]CaO1305-78-8

5% slurry Granules, pebbles90 to 96% asCaO


• Bulk liquid is preferred:store as an on-siteprepared slurrycontaining 5 wt% asCaO.

• Dry: if adequate liquidstorage is not possibleor practical, store inbags on pallets, inbarrels, or in bulk tank,60 days max. Providedust collectors, hopperagitator, and hopperslope of 60°.

Forms calcium hydroxidewith water (exothermicreaction), low solubility;hydroscopic; mildlycorrosive if wet. Irritateseyes, mucous membrane,and skin. Keep dry andcool.


ChlorineCl27782-50-5

100% Liquefied Gas One-TonCylinder

• Minimize cylinders onsite.

Yellow, pungent gas,extremely reactive in wetconditions; forms densewhite vapor withammonia. Toxic gasirritates skin, eyes, nose.

6

Clay[Bentonite]

H2O • (Al2O3 •Fe2O3 • 3MgO)

4SiO2 • nH2O

1318-74-7 (Clay)1302-78-9 (Ben.)

5% Slurry Powder, granules Bags, bulk (railcar or truckload)

• Bulk liquid is preferred:store as an on-siteprepared slurrycontaining a maximumof 5 wt% Bentonite.

• Dry: if adequate liquidstorage is not possibleor practical, store inbags or in bulk tankwith hopper agitation.

Inert, absorbs waterquickly; higher concen-trations produce viscousslurries; proper mixingrequired. No significanthazard. Avoid inhalingBentonite dust.

2

CorrosionInhibitorsa) Phosphate/PhosphonateBased Inhibitorb) All OrganicInhibitorc) Zinc orMolybdenumBase InhibitorSystems

As recommendedby vendor

Varied Varied • As recommended byvendor.

• As recommended byvendor.

1 or 7

Cyclohexylamine[NeutralizingAmine]C6H11NH2108-91-8

40% C6H11NH2 Liquid, blendedwith otherneutralizingamines

Tanks, drums • Keep container closedwhen not in use. Keepfrom freezing.

Ignitable. Liquid andvapor irritate skin andmucous membranes.Strong alkaline. Useprotective clothing/ glovesand eye protection.

1






CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

Defoamer As recommendedby vendor

Variable strengthDry:Paste:Liquid:

Packages, bulkPackages, bulkDrums, bulk

• Liquid is preferred:store in tight containersin cool, shaded areas.Bulk or drum may beused depending onquantities used. Ifdelivered as paste ordry, prepare solutionon-site per manu-facturer's recommen-dations.

• Dry: followmanufacturer'srecommendations.

Specific precautionsshould be provided bymanufacturer. In general,avoid excessive handling,contact with eyes, andingestion. Somehydrocarbon basedproducts may beflammable, and they mayadd to the oil/greasemeasured on effluentsamples.


DiatomaceousEarth[Diatoms]61790-53-2

5% Slurry Dry Bags, bulk • Bulk liquid is preferred:store as an on-siteprepared slurrycontaining a maximumof 5 wt%Diatomaceous Earth.

• Dry: if adequate liquidstorage is not possibleor practical, store inbags or in bulk tank.

No significant hazard.Avoid inhaling dust. Wearprotective gloves andsafety goggles.

2

Dichloroisocya-nuric Acid Salts,Mixture[Sodium Bromide]2893-78-9

As required Granular solids Plastic pails,bins

• Store dry in the originalcontainer. Keepcontainer tightly closedwhen not in use. Storein cool, dry, well-ventilated area awayfrom heat and openflames. Keepcontainer off wet floors.

Strong oxidizer.Exothermic. Do not mixdirectly with reducingagents, other oxidants ororganic materials.Corrosive, cause eye andskin damage. Irritating tonose and throat. Harmfulor fatal if swallowed. Willburn with the evolution ofchlorine and equally toxicgases.

CalgonTower-Brom�

Feeder

Dispersants As recommendedby vendor

As recommendedby vendor

• As recommended byvendor.

As recommended byvendor.

1

EthylenediamineTetraacetic Acid[EDTA]C10H16O8N260-00-4

8% C10H16O8N2 Solution Truckload,Drums, Bulk • Keep container closed

when not in use. storedin a cool, dry,ventilated area

Liquid causes burns. Useprotective clothing/ glovesand eye protection.Forms chelants withhardness scale andcorrosion products.

1

Ferric ChlorideFeCl37705-08-0

32%FeCl3

Liquid35 to 45% FeCl3

Carboys, bulk(rail or tanktruck)

• Bulk liquid is preferred.Keep in a tightly closedcontainer, stored in acool, dry, ventilatedarea

Orange-brown syrupysolution. Burn skin, eyes,nose. Corrosive. Useprotective clothing/ glovesand eye protection.

1





CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

Ferric Sulfate(hydrate)[Ferriclean]

Fe2(SO4)3 •nH2O10028-22-5

20%Fe2(SO4)3

Crystallinegranules16 to 24% Fe

Bags, drums,bulk (rail car ortruckload)

• Bulk liquid is preferred:store as an on-siteprepared solutioncontaining 20 wt% asFe2(SO4)3.

• Dry: if liquid storage isnot possible orpractical, store in lightcontainers either insmall or bulk quantities.Bulk tank hopper wallsshould have minimum36° slope. Do not mixwith calcium oxide inconveying or dust ventsystem.

Mildly hydroscopic,soluble, corrosive if wet,cakes at high humidity,gray to brown color. Dustirritates lungs. Treatsolution as corrosive.Treat solution ascorrosive.

1

Ferrous Chloride[Waste PickleLiquor]FeCl27758-94-3

20 to 25%FeCl2

Liquid Drums, bulk(rail or tanktruck)

• Bulk liquid. Irritant of eyes, mucousmembrane, and skin. Useprotective clothing/ glovesand eye protection. Avoidinhalation of ferrouschloride dust or vapors.

1

Ferrous Sulfate(hydrate)[Green Vitriol]

FeSO4 • 7H2O7720-78-7

55%FeSO4

Crystallinegranules55% FeSO4


• Bulk liquid is preferred:store as an on-siteprepared solutioncontaining 20 wt% asFeSO4.

• Dry: if liquid storage isnot possible orpractical, store in smallor bulk quantities in dryarea at temperatures< 68°F (20°C).

Hygroscopic, soluble,cakes in storage,corrosive if wet. Irritant ofeyes, mucous membrane,and skin. Use protectiveclothing/ gloves and eyeprotection. Avoidinhalation of ferroussulfate dust or vapors.

1

Hydrazine11

N2H4H2O7803-57-8

35%N2H4H2O

85%N2H4H2O

Drums,Truckload

• Keep away from heat,sparks, and flame. Keepaway from sources ofignition. Do not store indirect sunlight. Store in atightly closed container.Store in a cool, dry, well-ventilated area away fromincompatible substances.Corrosives area.

Corrosive. Irritant of eyes,throat, and nose.Potential carcinogen.

1

Hydrochloric Acid[Muriatic Acid]HCl7647-01-0

30 to 40%HCl

Liquid36.5 to 38% HCl

Carboys,drums, bulk (railor tank trucks)

• Bulk liquid. Whendiluting, the acid shouldalways be addedslowly to water and insmall amounts. Neveruse hot water andnever add water to theacid.

Irritant of eyes, mucousmembrane, and skin. Useprotective clothing/ glovesand eye protection. Avoidinhalation of hydrochloricacid dust or vapors.Corrosive. Requires vaporscrubber system.

1, withvaporscrubber






CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

HydrogenPeroxideH2O27722-84-1

35, 50, or 70%H2O2(4)

(PreferredConcentration,35%)

Liquid35, 50, or 70%solutions

Drums, bulk(rail or tanktrucks)

• Bulk liquid is preferred:when small quantitiesare only usedsporadically, drumstorage has been used.Store in a cool(< 35C),well-ventilated darkarea separated fromcombustiblesubstances, reducingagents, strong bases,organics

Strong oxidant. Ignitable.Severe irritant of eyes,mucous membrane, andskin. Use protectiveclothing/ gloves and eyeprotection. Preventcontact with most metalsand their salts, alcohols,acetone, nitromethane,flammable liquids, andcombustible materials.Dilute spills with water.

1

Morpholine[Diethyleneimideoxide]C4H9NO110-91-8

40% C4H9NO Liquid, may beblended withother volatileamines.

Drums, tanks,bulk (tanktrucks)

• Store at temperatureabove 50°F (10°C).

Ignitable. Vapor irritatingto mucous membranes.Liquid is irritating to skin.Use protective clothing/gloves and eye protection.

1

NitrilotriaceticAcid[NTA]C6H9O6N139-13-9

As required Liquid Drums • Bulk liquid. Liquid causes burns. Useprotective clothing/ glovesand eye protection.Forms chelants withhardness scale andcorrosion products.

1

Octadecylamine[Stearylamine]C18H37NH2

124-30-1

50% C18H37NH2 Liquid Drums • Keep container closedto preventcontamination and lossof water from emulsionby evaporation. Keepfrom freezing.

Mildly irritating to skin andeyes. Corrosive.

1

Phosphoric AcidH3PO47664-38-2

34 to 37 wt%HPO3 or75% H3PO4(5)

Liquid75 to 87% H3PO4

Carboys, kegs,bulk (rail or tanktruck)

• Bulk liquid. Store in acool, dry, ventilatedarea away fromsources of heat,moisture, and directsunlight. Corrosive tomild steel. Store inrubber lined or 316stainless steel.

Irritant of eyes, mucousmembrane, and skin. Useprotective clothing/ glovesand eye protection. Avoidinhalation of phosphoricacid vapors. Corrosive.

1

Polyelectrolytesa) AnionicMW < 20,000

0.5 to 1.0%(6) Dry

Liquid

Bags, drums,bulkCarboys, kegs,bulk

• Bulk liquid is preferred:store as neat. Usepolymer supplies inorder received to avoiddeterioration with time.

• Dry: store in cool, dryarea, use polymersupplies in orderreceived to avoiddeterioration with time.Some solutionsprepared from drypolymer will deterioratein 1-2 days.

Depending on type, maybe irritant of eyes, mucousmembrane, and skin. Useprotective clothing/glovesand eye protection. Avoidinhalation of polymer dust.Spills are extremelyslippery - clean up spillsimmediately.

3





CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

Polyelectrolytes (cont)b) CationicMW >100,000

1.0 to 5.0%(6) Dry

Liquid





4

c) NonionicMW >1x106

0.5 to 1.0%(6) Dry

Liquid





3

Sodium Aluminate[Soda Alum]AlNaO21302-42-7

32% Al2O3 Crystals:55% Al2O3Liquid:32% Al2O3

BagsDrums, bulk(rail or tanktruck)

• Bulk liquid is preferred:store in 20 wt% asNaAlO2 solution.

• Dry: if adequate liquidis not possible orpractical, store asreceived. Maximumtemperature is 66-90°F(19-32°C).Deteriorates withexposure toatmosphere. Bulkstorage tank mayrequire hopperagitation.

White to brown powderand liquid. Corrosive ifwet, soluble. Exothermicheat of solution.Irritant of eyes, mucousmembranes, and skin.Corrosive. Cakes easily.

1






CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

SodiumCarbonate[Soda Ash]Na2CO3497-19-8

15%Na2CO3

Variable densitypowder95% as Na2CO

Bags, barrels,drums, bulk (railcar or truckload)

• Bulk liquid is preferred:store in 20 wt% asNaAlO2 solution.

• Dry: if adequate liquidis not possible orpractical, store asreceived. Maximumtemperature is 66-90°F(19-32°C).Deteriorates withexposure toatmosphere. Bulkstorage tank mayrequire hopperagitation.

Corrosive if wet, soluble,cakes on storage.Exothermic heat ofsolution.Dust irritates eyes,mucous membranes, andskin.

1

SodiumHydroxide[Caustic Soda,Soda Lye]NaOH1310-73-2

50% NaOH(4)(7) Flakes, lumps98.9% NaOHLiquid: 12 to 50%NaOH

DrumsBulk (rail or tanktruck)

• Bulk liquid is preferred:store in solutioncontaining 50 wt% asNaOH, above freezing.

• Always add the causticto water while stirring;never the reverse. Anoutside tank should beequipped with a steamcoil.

Produces heat ondissolving in water (careon solution make-up);soluble; very hygroscopic.Corrosive. Burns eyes,mucous membranes, andskin. Use protectiveclothing/ gloves and eyeprotection.

1

SodiumHypochlorite[Javelle-Water,Chlorine Bleach]NaOCl7681-52-9

13 to 17%NaOCl

Liquid solution5 to 15% Cl2

Bulk (55-galdrums, tanktruck)

• Bulk liquid is preferred:store in 12% solution.

• Tanks should beprotected from UV raysand direct solarradiation.

Yellowish solution, strongalkalinity and corrosive.Strong oxidant. Irritatesskin, eyes, nose.Bleaches fabrics. Storecool and dark.

1

SodiumMetaphosphate[Glass SodiumPhosphate](NaPO4)x; x = 6,1310124-56-8

3%(NaPO4)x;x = 6, 13

65 to 68% P2O5 Bags • Store above 40°F (4°C)without freezing.

Irritates eyes on contactand skin on prolongedcontact.

1

SodiumPhosphate(monobasic)[MonosodiumPhosphate]NaH2PO4H2O10049-21-5

3% NaH2PO4H2O Dry Bulk, truckload,bags

• Store above 40°F (4°C)without freezing.


2





CHEMICALSNAME


SOLUTIONSTRENGTH

FEDWEIGHT %

COMMERCIALFORMS &

STRENGTHSWEIGHT %

SHIPPINGCONTAINER




FEEDSYSTEM

FIG #

SodiumPhosphate(dibasic)[DisodiumPhosphate]Na2HPO47558-79-4

3% Na2HPO4 Dry Bulk, truckload,bags

• Store above 40°F (4°C)without freezing.


2

SodiumPhosphate(tribasic)[TrisodiumPhosphate]Na3HPO4 12H2O10101-89-0

3%Na3HPO4 12H2O

Dry Bulk, truckloads • Store above 40°F (4°C)without freezing.


2

Sodium Sulfite10

Na2SO37757-83-7

20% Dry95 to 100%Na2SO3

Bulk, bags • Keep bags closed anddry when not in use.Keep away from strongoxidizers.

Irritates eyes, nose, andskin. Use face shield andrubber gloves.

2

Sulfuric Acid[Oil of Vitriol]H2SO47664-93-9

93 to 98%(8) LiquidCommon grades77.7 and 93.2%H2SO4

Carboys,drums, bulk (railor tank truck)

• Bulk liquid: store insolution containing 93-98 wt% as H2SO4.Minimum temperatureis 30°F (-1°C).

Strong acid, hygroscopic,produces intense heat tomixing with water. Onlyadd acid to water. Dilutesolutions very corrosive.Causes burns to skin.Use protective clothing/gloves and eye protection.Avoid inhalation of sulfuricacid vapors.

1

UreaNH2CONH257-13-6

40%Urea

Crystalline solid,46% NH2CONH2

Bulk, carloads• Keep in tightly closedcontainer, stored in cool,dry, ventilated area.

Causes irritation to eyes,skin, and respiratory tract.


Volatile OxygenScavenger

(OndeoNalco:Eliminox,Surguard)

(GEBetz:Cor-Trol778, DiethylHydroxylamine

(DEHA)) (Drew Amersities)

Vendor Specified Vendor Specified Varied • As recommended byvendor.

1

Notes:(1) Obtaining and reviewing the Supplier Materials Safety Data Sheet (MSDS) for these chemicals is recommended. Where warranted,

substitutes should be evaluated.(2) CAS: Chemical Abstracts Service.(3) For materials of construction information, see DGs 11-6-1, 11-6-2, and 11-6-3.(4) Concentration above 50% requires special handling precautions.





(5) Maximum temperature 212°F (100°C).(6) Delivered solutions considered neat.(7) Minimum temperature 51°F (11°C) and maximum temperature 118°F (48°C).(8) Minimum temperature 30°F (-1°C) and maximum temperature 70°F (21°C).

(9) Carbide lime (calcium carbide) is not recommended as a source of calcium oxide or hydroxide in water or wastewater treatment due othe release of acetylene gas when the calcium carbide is dissolved in water and the associated safety concerns with acetylene gas.

(10) Liquid with a Cobalt Catalyst

(11) This chemical has been labeled a carcinogen and calls for stringent handling procedures. For this reason, its use has beendiminishing and chemical suppliers have developed alternatives.




TABLE 3STANDARD WATER/WASTEWATER ANALYSIS SHEET

CONSTITUENTS ppm (mg/l) AS I II IIICalcium (Ca++) CaCO3Magnesium (Mg++) CaCO3Sodium (Na+) CaCO3Ammonium (NH4+) CaCO3

CATIONS

Total Cations CaCO3Bicarbonate (HCO3-) CaCO3Carbonate (CO3-) CaCO3Hydroxide (OH-) CaCO3Sulfate (SO4-) CaCO3Chloride (Cl-) CaCO3Nitrate (NO3-) CaCO3

ANIONS

Total Anions CaCO3Total Hardness CaCO3

“M” (Methyl Orange) Alkalinity** CaCO3

“P” Alkalinity** CaCO3

Phosphates PO4-

Iron, Total FeAluminum, Total AlCopper, Total CuCarbon Dioxide, Free CO2Silica SiO2Biological Oxygen Demand (BOD)Chemical Oxygen Demand (COD)Hydrocarbons CTurbidity N.T.U.Color –pH –

Notes:** Attach titration curve, if available.Column I Raw Water/Wastewater Analysis.Column II Maximum Allowable Impurities for the Stream (e.g., Makeup to Deaerator, to Cooling Tower, Process Stream).Column III Modified Analysis Resulting from Each Treatment Step, if any.





TABLE 4SELECTION CHART FOR BENCH SCALE POLYMER TESTING PROCEDURES

BENCH TESTING PROCEDURES

FULL-SCALE UNITPROCESS

INITIALSCREENING

PERFORMANCECRITERIA

SELECTIVETESTING

PERFORMANCECRITERIA

Primary Oil/WaterSeparators (API, CPI)

Jar Test(ASTM D2035)

Floc FormationRise RateWater Clarity


Resultant Turbidity

Water TreatmentClarifier


Floc FormationSettling RateWater Clarity


Resultant Turbidity

Dissolved Air Flotation(DAF)


Floc Formation SizeWater Clarity

Bench Model DAFUnit

Resultant Turbidity

Induced Air Flotation(IAF)

No Suitable ScreenTest Exists

No Suitable Screen TestExists

Bench Model 1 + 1Unit or Nozzle AirUnit

Resultant Turbidity

Secondary Clarifier Jar Test(ASTM D2035)

Floc FormationSettling RateWater Clarity

Cylinder Settling Test(St. Method 2710)

Zone Settling VelocitySludge Volume Index

Sludge ThickeningA. GravityB. DAF


Floc Settle or Rise RateSize

A. Cylinder SettlingTest

(St. Method 2710)B. DAF Test

Zone Settling VelocitySludge Volume IndexSludge Cake DrynessFloat TotalSuspended Solids

Sludge DewateringA. High Shear (e.g.,

High PressureFiltration)

B. Low Shear (e.g.,Belt Filter Press)

A. CST Test(St. Method 2710 G)B. Squeeze Test

A. Minimum CSTFloc StabilityWater Clarity

B. Floc FormationSettling RateWater Clarity

A. Time to FilterTest

(St. Method 2710 H)B. CST Test(St. Method 2710)

A. Cake DrynessB. Minimum CST

Floc Characteristics

Notes:(1) CST – Capillary Suction Time.(2) For procedures of the Bench Model DAF Test and Bench Model 1 + 1 Unit, refer to EE.20E.84, Polyelectrolyte Guide, and contact

your local DAF and IAF vendors.(3) For all other tests, refer to Reference 8.




FIGURE 1CONTROLLED VOLUME PUMP FEEDER

(DIAGRAMMATIC LAYOUT OF EQUIPMENT AND PIPING)

MA

(Note 6)Vent

DilutionWaterInlet

(Note 5)

TruckConnection

BulkStorageTank

(Note 9)

(Note 7)

LG

1/2 in. LGLG

PI

FG

STRxxx

(Note 1)(Note 4)

SatelliteFeed Tank

CalibrationPot

(Note 2)PR Valve

PRxxx

Sight FlowIndicator(Note 3)

SolutionOut

M

501 in.NPS

SedimentPot1 in.

NPSOverflow

Drain orContainmentArea (Note 8)

Notes:(1) Gage glass or equivalent with calibrated gage board.(2) PR Valve to be furnished even when buit-in relief valves are provided with pumps.Set pressure to be a minimum of 10%

above the operating pressure at the pump discharge, or 10% above the process equipment design pressure whichever isgreater.

(3) Sight flow indicator with flapper.(4) Satellite feed tank required when chemical mixing and storage are done in the same tank. The satellite tank is used when the

main tank is being used for preparing new batch requiring over 4 hrs. preparation time.(5) Dilution water connection as required for diluting chemical strength used.(6) Method of chemical addition and tank top arrangement shall be selected to suit chemicals to be used and to meet local safety

and environmental regulations.(7) Gage glass not required if tank is constructed of transparent plastic.(8) Drain shall be visible from dilution water inlet line.(9) Fixed cover and nitrogen purge, floating cover, or plastic balls required for sulfite and hydrazine.

DP19A9f01





FIGURE 2TYPICAL DRY CHEMICAL FEEDER


Notes:(1) Recycle takeoff to be as close as possible to application point.(2) Soft water total hardness < 5 ppm (5 mg/L) required for solutions with pH > 7.5.(3) Level transmitter shall be extended - diaphragm type.(4) Unloading line to be 4 in. NPS unless otherwise specified.(5) Magnetic type flow indicator or mass flow indicator.(6) Timer to control line flushing on periodic basis.(7) Emissions control as required by local safety and environmental regulations.(8) Silo bottom shall be designed to prevent material bridging.(9) Drain shall be visible from unloading connection.(10) Spare pump configuration not shown.

(Note 7)

(Note 8)

StorageSilo

RotaryValve

SurgeHopper

PICxxx

FFCxxx

LVxxxM

MAVolumetric/Weight Feeder

TruckPneumaticUnloading(Note 4)

LAHLAL

LICxxx xxx

KCV

(Note 3) (Note 6)

(Note 2)

DilutionWater Inlet

(Not

e 1)

PIFVxxx

M

M

(Note 5)

(Note 10)1in. NPS

ToTreater

Drain orContainment Area

(Note 9)

ACCEPTABLE METRIC EQUIVALENTS

in.mm

1 NPS25

4 NPS100

DP19A9f02

xxx

FAL

FIC

LAHLAL




FIGURE 3ANIONIC AND NONIONIC POLYELECTROLYTE FEED SYSTEM


Batch Logic

Vent MA

LHCOxxx

Vent

DilutionWater

PRxxx

(Note 3)(Note 6)

BulkStorageTank

LG PI

TruckConnectionUnloading ofPolyelectrolyte

Ove

rflow

Drain orContainmentArea(Note 6)

PRxxx

PR Valve(Note 3)

PI

M

LG

CalibrationPot

(Note 1)

STRxxx(Note 7)

FG

M

Sight FlowIndicator(Note 2)

ToTreater

SedimentPot

Vent

LALLL(CI)xxx

(Note 4,5)

MixtureStorageTank0.1 - 0.5%

1 in.NPS

1 in.NPS

MA

Notes:(1) Gage glass with calibrated gage board.(2) Sight flow indicator with flapper.(3) PR Valve to be furnished even when built-in relief valves are provided with pumps. Set pressure to be 10% above the

operating pressure at the pump discharge or 10% above the process equipment design pressure, whichever is greater.(4) Differential gap controller.(5) On mixture storage tank low level, the bulk storage tank transfer pump shall operate for a set time. Dilution water shall then

be added to the mixing tank until the LHCO is reached.(6) Drain and level Gage shall be visible from unloading connection.(7) Spare pump configuration not shown.

ACCEPTABLE METRIC EQUIVALENTS1 in. NPS

25 MM

DP19A9f03





FIGURE 4CATIONIC POLYELECTROLYTE FEED SYSTEM


MA Vent

(Note 4)LGBulkStorageTankO

verfl

ow

TruckConnectionUnloading ofPolyelectrolyte

Drain orContainment

Area(Note 4)

(Note 1)

(Note 2)

LG

PI

PRxxx

FilteredDilutionWater

PHA

FICxxx

(Note 5)

STRxxx

M

CabibrationPot

SedimentPot

1 in.NPS

1 in.NPS

MixingTee

StaticMixer

(Note 3)

ToTreater

Notes:(1) PR Valve to be furnished even when built-in relief valves are provided with pumps.Set pressure to be 10% above the

operating pressure at the pump discharge or 10% above the process equipment design pressure whichever is greater.(2) Gage glass with calibrated gage board.(3) Some high MW Cations polymers may require a high shear mixing unit.(4) Drain and level Gage shall be visible from unloading connection.(5) Spare pump configuration not shown.

ACCEPTABLE METRIC EQUIVALENTS

1 in.NPS

25 mm

DP19A9f04




FIGURE 5FLOW THROUGH SOLID FEEDER FOR HYDANTOIN CHEMICAL(6)


(Note 5)PR Valve

(Note 2)

(Note 3)

Note: 4

(Note 2)

Timer

(Note 1)DilutionWater Inlet

Drain

PxxxI

FxxxI

Drain

Drain

PxxxI

To Treater

DP19A9f05

Notes:(1) Dilution water shall be cooling tower makeup.(2) Distributors and collectors shall be wedge wire screeing with a slot width to retain granular material in the vessel.(3) Top is flanged for loading of vendor granular material by a method approved by Owners Engineer.(4) Vessel is to be built to ASME Code.(5) Set pressure equal to or less than vessed rating, which shall be equal to or greater than the dilution water shut-off

pressure.(6) Solid flow through feeders shall not be used for dichloroisocyanric acid salts, mixture (sodium bromide).





FIGURE 6TYPICAL RECIRCULATED COOLING WATER SYSTEM


Acid InjectionPumps

SupplyConnection

AcidStorage

Tank

Auxiliary PumpHand Switch

SpareM

MSV

SV

FI

HS

LHA

LLA

LICFrom RawWater Source

See Detail "A"

FI

HingedCoverWater

Ove

rflow

SV SV

LI LLAM

M

SedimentPot HS

AuxiliaryPumpHand Switch

Stea

mSpare

InhibitorStorage (& Mixing)Tank

Inhibitor InjectionPumps

M M

T

GLFo(s)

Cooling WaterRecirculation

Pumps SelectorSwitch

PL(CI)A

PLCI

Inhibitor

Rec. or Ind.

Rec. or Ind.

Rec. or Ind.Corrosivity

Conductivityor Indicatorph Recorder

AutomaticController

Blowdown toWastewater

Sewer

FO(s)

Flow Valve

Filter

SidestreamFilter

LP

Chlorinator

ProcessUnit

FE

FE

FE

PowerPlant

ProcessUnit

Cooling Water Return

FFR RT

I

Six - Cell Cooling Tower

Trash Racks and ScreensSuction Bay

ChlorineCylinder

Chlorine isDistributedAlong back ofBasin OppositeCirculatingPumps

Over-FlowWeir

THATLA

TI

FR

FI

LP

DP19A9f06

OilSkimming

AIC

Cl'2

P

LILLA

Notes:(1) Piping for concentrated acid may be carbon steel. The acid

injection tube should be polypropylene.(2) Rubber or polypropylene lining is required about 2 feet

upstream and 4 feet downstream of injection point.

MakeupWater

Detail "A"

Acid Mixing TeeNote 1

dp19a9

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