Landfarm Operator Certification Chapter 2: Waste Characterization
Mar 29, 2015
Landfarm Operator Certification
Chapter 2: Waste Characterization
Waste Characterization
General Objective
• Explain the differences between special and solid wastes
Specific Objectives
• Identify types of special wastes and their properties
• Identify types of solid wastes and their benefits or concerns in land application
Special Waste
High volume, low hazard waste remaining after processing of materials
Waste from individuals, businesses, industries or municipalities
Special Wastes
1. Mining wastes
2. Utility wastes (fly ash, bottom ash, scrubber sludge)
3. Wastes from coal gasification (vitrified coarse solids residue, prilled or blocked sulfur)
Special Wastes
4. Sludge from water treatment facilities
5. Sludge from wastewater treatment facilities
6. Cement kiln dust
7. Gas and oil drilling muds
8. Oil production brines
Domestic Septage is not Special Waste
• Liquids or solids from
1. Septic tank2. Cesspool3. Portable toilet4. Type III marine sanitation device5. Anything similar that only receives sewer waste
Water Treatment SludgeSolids and liquids removed during the processing of potable water
1. Suspended and dissolved solids 2. Coagulants (aluminum sulfate, ferric chloride,
ferric sulfate3. Polymers4. Lime5. Metal oxides
Water Treatment Sludge
Organic matter, soli particles, etc are filtered out during treatment
Low in organics
Low in nutrients beneficial to crops
Only Calcium would be beneficial for pH control if land applied
Water Treatment SludgeMay contain micronutrients that are beneficial
Could also contain heavy metals which have to be tested for and could be detrimental 1. Cadmium2. Lead3. Copper4. Nickel5. Lead6. Zinc
Wastewater Treatment SludgeSolids generated during wastewater treatment
process
Contains biological, chemical, and physical contaminants
93-99% liquid when initially removed form the process
Wastewater Treatment SludgeSolids generated during wastewater treatment
process
Contains biological, chemical, and physical contaminants
93-99% liquid when initially removed form the process
Wastewater Treatment SludgePrimary Sludge - raw sludge unstable and not
suitable for land application
Secondary Sludge – solids content is 0.5-2.0% after biological treatment and stabilization
Activated Sludge – secondary sludge collected from settling tanks…contains bacteria cells stabilized organic matter and inorganic compounds
Wastewater Treatment SludgeStabilized Sludge – secondary sludge after
microbial processing or chemical addition
Aerobic Sludge – activated sludge produced by injecting air
Anaerobic Sludge – activated sludge produced by excluding air, heat may be added to speed reactions
Wastewater Treatment SludgeChemically Stabilized Sludge – results form the
addition of chemicals during secondary treatment• Decrease biological activity• Reduce pathogens• Reduce odor• Increase % solids• Common in domestic waste treatment
Wastewater Treatment Sludge
Dewatered Sludge – mechanically stabilized sludge with water removed
15-20% solids
Belt, frame, and centrifuge presses are used to separate the solids
Wastewater Treatment Sludge
50% of wastewater sludge is organic dead microbe cells
Contain nutrients for plant growth as well as heavy metals
Some pathogens may remain, reduce pathogens before land applying
Wastewater Treatment SludgeContains synthetic organic chemicals
generated by households and industries
E.P.A. reviews sewage sludge regulations every 2 years
Contaminants of Emerging Concern are evaluated for possible land application1. Pharmaceuticals2. Personal Care Products
Fly Ash
Fine mineral emitted into the smoke stack of coal fire boilers that contains
1. Phosphorus 2. Potassium3. Calcium4. Magnesium5. Sulfur 6. Boron7. Molybdenum
Fly Ash
Can help neutralize soil pH
Improve moisture holding capacity
Fresh fly ash is toxic to plants
Exposure to atmosphere prior to land application reduces salinity and toxicity to plants
Lime Scrubber Sludge
Result of scrubbing sulfur dioxide from stack gases of coal fired power plants that use a liquid suspension of finely ground limestone
Solids content 50% after holding ponds remove water
Must be stabilized before land applying
Lime Scrubber Sludge
Stabilize by adding
1. Lime2. Fixing agents3. Sodium silicate4. Cement
May contain fly ash
Lime Scrubber Sludge
Mixing of the dried limestone scrubber sludge and fertilizer containing nitrogen, phosphorus, and potassium can help support vegetative growth
Fresh sludge may be toxic and unstable and contain heavy metals
Fluidized Bed Combustion Waste
Fine coal dust that burns in a bed of inert ash and ground limestone
Air injected where the ground limestone reacts during coal combustion suspends the bed
Fluidized Bed Combustion Waste is a fine, solid, granular material
Fluidized Bed Combustion Waste
Contains calcium sulfite, unreacted lime, and metal oxides with high pH levels
Moisture and heat convert the metal to metal hydroxides
Carbon dioxide in the atmosphere stabilizes the material by forming carbonates
Fluidized Bed Combustion Waste
Unstabilized FBCW should not be land applied
Stabilized FBCW provides sulfur, calcium, and lime for pH adjustment which helps plant growth
10-40% lime value
Transportation costs will limit BFCW as a liming agent
Gas and Oil Drilling Mud
Fluids pumped into the borehole to lubricate and cool the drilling bit, float loose material, seal porous strata, and prevent the borehole from filling with water
Most muds contain trace elements, petroleum residue, salt water components, and sources of alkalinity (barium sulfate, bentonite, chrome lignosulltonate, lignite, and sodium hydroxide)
Gas and Oil Drilling Mud
Most is dewatered to >20% solids
Soluble components are leached out and insoluble components remain in the cell with the drilling mud
Mud is removed once it is deemed to pose little or no environmental hazard
Gas and Oil Drilling Mud
Stabilized drilling mud is used as industry fill material
Analysis for heavy metals as well as Polycyclic Aromatic Hydrocarbons should be performed prior to land application
Oil Production Brines
Result of water and oil separation in oil well
When an injection well is not available for handling brines, it is considered a special waste by regulation
High salt content and toxic to plants
Analyze for sodium, chlorine, alkalinity and heavy metals before land applying
Solid Waste
Discarded material that is not hazardous waste, special waste, coalmining waste, or agricultural waste
Soil, sand, rock, and gravel are solid wastes
“Agriculture waste exemption” applies to manure, crop, and crop residue
Solid Waste
Solid or dissolved material in domestic or industrial water or wastewater while in process is regulated by Kentucky Pollutant Discharge Elimination System
Cement Kiln Dust
Fine granular solid material obtained from mixing several waste sources during cement manufacture
Dust from stack scrubbers, grinding rock and shale, impurities before the raw product passes through the rotary kiln
Cement Kiln Dust
Cement Kiln dust should be analyzed for hazardous waste content
Has a high pH
Can be mixed with biosolids to help with pathogen reduction
The high pH decreases nitrogen content
Cement Kiln Dust
After time the pH gets back to levels suitable for land application
Analysis should be the same as biosolids with the addition of the alkalinity being checked
Food Wastes
Results of food production, processing, and food supplement processing
These include liquid and solid wastes
Contain high Biological Oxygen Demand
Some materials represent crop residues that are easily land applied
Food Wastes1. Whey from cheese making and rejected milk2. Starch, peels, and rejects from potato chips3. Trimmings and rejects of vegetables and fruits from
restaurants and grocery stores4. Pomace from fruit processing5. Tomato pulp from catsup6. Hulls and skins from peanut processing7. Dust and hulls from coffee grinding and oil seed
extraction 8. Spent media from drug and food supplement
manufacturing
Food Wastes Analyze for BOD concentrations and presence
of chemicals used in processing
Application to prevent decomposition resulting storage that leads to odors
Other Solid Wastes
Sawdust, wood chips, and leaves
Permit by Rule due to low potential for environmental harm
No written application or authorization is required to land apply
Permit by rule activities must comply with Environmental Performance Standards
Other Solid Wastes
Setbacks from streams or other Waters of the Commonwealth should be observed
Wood wastes can benefit soil conditions long term because they are very high in carbon compared to nitrogen content
Nutrient magement should be intensified when wood wastes are applied
General Objective
• Explain the differences between special and solid wastes
Specific Objectives
• Identify types of special wastes and their properties
• Identify types of solid wastes and their benefits or concerns in land application
Landfarm Study Guide
Chapter 1
1. Special Wastes are those materials of high volume and low hazard.
A. TrueB. False
10
2. Sludge can be applied to the land in the form of:
A. LiquidB. Semi-solidC. Solid dryD. All of the above
10
3. Which of the following is not a special waste?
A. Utility wasteB. Water treatment
sludgeC. Wood chipsD. Cement kiln dust
4. Cement kiln dust can be combined with wastewater sludge to meet pathogen reduction requirements by decreasing pH.
A. TrueB. False
10
5. Some of the microorganisms entering the treatment plant are regarded as
.
A. PathogensB. UnreactedC. CoagulantsD. Alkaline
10
6. A concern of relatively unprocessed food waste is the biochemical oxygen demand (BOD) level of these wastes.
A. TrueB. False
10