Where do Landfills Fit In The Changing Paradigm of ...uest.ntua.gr/naxos2018/proceedings/presentation/3... · Wastewater Treatment Plant Landfill Leachate ... Solid Waste Landfill

Where do Landfills Fit In The Changing Paradigm

of Circular Economy-Resource Recovery and

Social Aspects

ByAditi Podder1, Debra Reinhart2 and Ramesh Goel3

1,3Department of Civil & Environmental Engineering, University of Utah2Department of Civil, Environment, Construction Engineering, University of Central Florida

Liquid Waste-streams in Urban Environment

Ref: SPUHLER (2010)

Solid Waste

Wastewater Treatment PlantLandfill

Leachate

• All the waste-streams are contaminated• Contaminants of concerns are mainly

Carbon, Nitrogen and Phosphorus• Industrial Wastewater and liquid

generated from solid waste also contains metals and toxic chemicals

HOW CAN WE ACHIEVE ENVIRONMENTAL SUSTAINABILITY??

Two Urban Waste streams rich in resources

Filtrate/Centrate/Reject water

URBAN WASTESTREAMHigh Ammonia Content

Sent back to Biological Treatment Train Increases Ammonia Load inside Bioreactor

AnaerobicDigester

SludgeDewater

LandfillSolid Waste LeachateDUMPED INTO WWTP

High Ammonia Content Low Phosphorus Content High Toxicity

Low BOD/COD ratioHigh recalcitrant mattersHigh dissolved methane COMPLEX WASTESTREAM

Parameter CompositionCOD (mg/L) 100~400

NH4+-N (mg/L) 400~1000

TN (mg/L) vairableTP (mg/L) 200~400

Characteristics of Typical Filtrate

Liquid waste Treatment (Carbon management)Different Aerobic Reactors Performance (Renou et al., 2008 )

Figure: (a) Activated Sludge Process, SUEZ's degremont, water handbook; (b)SBR, Beun et al.,1988; (c)MBBR, Colloide Engineering,ENVIROPRO; (d)Trickling Filter

(a)

(c)

(d)

(b)

Liquid Waste Treatment (Carbon management)Different Anaerobic Reactors Performance (Renou et al., 2008, Fernandez et al., 2000 )

Figure: Anaerobic DigesterSource: A Primer on Anaerobic Filters, Fundamentals & Applications

The need to integrate “recover” with “removal”• Landfill leachate is rich in N and C, and handled separately.• The current management schemes focus on removal which is also threatened by the presence of recalcitrant and toxic chemicals in landfill leachate• Wastage of C, N and P• Dumped into WWTP

Current paradigm

Circular Metabolism• Recognizes the fact that waste streams contain valuable resources• Most important ones are nitrogen and phosphorus• Provides a much reduced burden to stakeholders and the environment

Overcome P limitations by mixing two concentrated streams

BOD5 (mg/L) 58_5

COD (mg/L) 1435_10

Ammonia (mg/L) as N 457_5

Phosphorus (mg/L) 7.6_2

Nitrate as N (mg/L) <0.01

Nitrite as N (mg/L) <0.01

TOC (mg/L) 280_5

BOD5 (mg/L) 79_5

COD (mg/L) 450_25

Ammonia (mg/L) 485_15

Phosphorus (mg/L) 400±25 

Nitrate as N (mg/L) 1.2 _ 0.2

Nitrite as N (mg/L) 0

TOC (mg/L) 128_12

BOD5 76_5

COD(mg/L) 547_10

Ammonia (mg/L) 435_10

Phosphorus (mg/L) 250±35

Nitrate as N(mg/L) <0.01

Nitrite as N (mg/L) <001

Characteristics of Leachate

Characteristics of Mixture (20%Leachate+80% Filtrate)

Characteristics of Filtrate

+

+

+

+

+

+

+

+

+

+

+

+

+ Final concentration depends upon the ration two waste streams are mixed

Implementation of Circular Metabolism

Environmental Issues Economical Issues Societal Issues

Environmental Sustainability can be achieved with a proportional balance of these THREE issues

Recovering Nutrients Provide Environmental Sustainability

• Recovering useful nutrients make the nutrients available for further use which boosts economy

• Generated methane gas can be used in electricity generation in wastewater treatment plants

• Composts generated from landfills and from biosolids can be sold in market for agricultural purpose

• Reused/ reclaimed water can also contribute in economy

• If prior to dumping the nutrients into water bodies, they can be recovered, the risk of algal bloom can be reduced

• Instead of dumping the organics and nutrients, if they are treated and recovered, additional source of chemicals in treatment of water can be reduced

• A green environment can be expected if the treated water (rich in nutrients) can be used for agricultural purpose

• Water reuse will ensure the balance in fresh water resources for future generation

• Recovered nutrients will need to be processed for downstream uses which might increase job opportunity

• When the concept of scarcity and limited availability of resources will be widespread, more public participation is accepted, which will also provide job opportunity

Challenges-Leachate CharacteristicsSLVSWMF Leachate Sampling, American West Analytical Laboratories (2016)

Huan‐jung et al. (2006)

Raghab et al.(2013)

Robinson et al.(2017)

Zazouli et al. (2012)

BOD5 (mg/L) 58 20-57000 3400 7.6 48COD (mg/L) 1590 140-15200 8250 1900 3960

NH4+ (mg/L) as N 168 50-2200 3745 1200 532

Phosphorus (mg/L) 1.9 0.1-23 1308 7.83 21Nitrate as N (mg/L) <0.01 nd 3.95 1800 ndNitrite as N (mg/L) <0.01 nd nd 1.05 nd

TOC (mg/L) 280 30-29000 nd 776 nd

Low Biodegradable Organics presentHigh in ammonia nitrogen but low in phosphorusDue to low P, strategies like struvite precipitation not feasible

Challenges and solutions•Variable characteristics of leachate make it difficult to develop a single management option.

•High ammonia and low phosphorus leaves plenty of ammonia nitrogen P in the liquid waste even after nutrient recovery

•Hence, integrated approaches are needed to manage leachate. 

Proposed Integrated approach Approach

RECOVER NUTRIENTS

REUSE WATER

TREAT WATER

Microbial Protein Production-for excess ammonia

• Promising alternative in promoting Circular EconomyLow value recovered resources High quality feed• NH4

+-N + CO2 High quality edible microbial protein

Crude protein content on CDW basis of the microbial biomass produced under CR configuration by the Sulfuricurvum spp. dominated culture compared with other microbial protein (bacterial meal), animal protein (fishmeal) and vegetable protein (soybean meal) (Matassa et al., 2016)

Electrochemical Ammonia Recovery from Source Separated Urine for Microbial Protein Production (Christiaens et al., 2017)

H2 oxidizing Bacteria

• Supports a shift from resource dissipation to resource recovery

• Can be used as a suitable substitute for conventional feed sources such as fishmeal or soybean meal

From Effluent of Wastewater Treatment Plant

From Biogas produced during Anaerobic Digestion

From Green Energy Sources such as Wind & Solar Energy powered Water Electrolysis

RESOURCE RECOVERY UNDER CIRCULAR ECONOMY

Optimization of pH and Mg: P ratio during struvite precipitation

Struvite Precipitation in Recovery of Phosphorus

NH4+

Mg2+

PO43- NH4

+

Mg2+

PO43-

pH = 9

P:Mg = 1:1.2

MAXIMIZES PRECIPITATION

Phase I

Phase II

Phase III

COD removal percentages in granular reactor

Knocking down Carbon in Granular Reactor• Granular Sludge Technology is a

Novel Approach in simultaneous removal of Organics, Nitrogen and Phosphorus

(a) Conditions inside granules (b) Microorganisms abundance in flocs (Winkler et al., 2012)

(a) (b)

08. 22. 2017 12. 15. 2017 02. 27. 2018FEEDING WITH REAL LEACHATE CHANGES THE MORPHOLOGY OF GRANULES

Phase I Phase IIPhase III

Ammonia nitrogen removal percentages in granular reactor

Treatment of Ammonia- Nitrogen in Granular Reactor

Low Energy Cost

<60% of BNR

v

Low Carbon Footprint

<40% of BNR

SimultaneousP and N Removal

Microbial Diversity

High Settle-ability

Effective for high strength WW

AEROBIC GRANULES

Phase I

Phase II

Ammonia nitrogen removal percentages in PN/A reactor

Phase III

Treatment of Ammonia- Nitrogen in Single Stage PN/A

Processes Nitrification-

denitrification

Nitritation-

denitritation PN/A

O2 demand

(kg O2/kg NH4+-N)

4.57 3.43 1.95

Alkalinity demand

(mg CaCO3/mg NH4+-N)

7.07 N/A 4.6

BOD demand

(kg BOD/kg NH4+-N)

~ 3.5 ~ 2.1 0

Biomass yield

(kg DS/kg NH4+-N)

~ 0.8 ~ 0.5 ~ 0.1

• Benefits of PN/A

Stoichiometry:NH4

1.32NO2 0.066HCO3

0.13H 0.066CH2O0.5N0.15 1.02N2 0.26NO3 2.03H2O

NH4 1.146NO2

0.07HCO3 0.057H 0.071CH1.74O0.31N0.20 0.986N2 0.161NO3

2.002H2O

NH4

+ NO2

-

N2

Partial nitritation AnammoxPN/A=

(a) Suspended Growth Granular Anammox (Jian-Tang et al.,2013)(b) ANITATMmox, Veolia Water Technologies

(a)

(b)

ANaerobic AMMonium Oxidation (Anammox)

Integrated Approach in Treatment of Landfill Leachate

INFLUENT EFFLUENT

RECOVER NUTRIENTS

REUSE WATER

FERTILIZER

STRUVITE PRECI-PITATION

PARTIALNITRITATION/ANAMMOX

GRANULARACTIVATEDSLUDGE PROCESS

Org-NH4+

PO43--P

rbCODOrg-NH4

+

PO43--P

rbCOD

Org-NH4+

PO43--P

rbCOD

Org-NH4+

PO43--P

rbCOD

TEAM GREEN

Conclusions• There is a need to think beyond the conventional treatment

paradigm and incorporate recovery and innovative processes.

• Single management approach may not be suitable due to constantly changing leachate characteristics.

• Leachate cannot be considered as a separate “one” liquid waste stream. It should be considered under the broader spectrum of urban circular metabolism.

• Our integrated approach incorporating struvite recovery, granular activiated sludge process and single stage anaerobic ammonia oxidation showed good promise.

THANK YOU

Contact InformationDr. Ramesh Goel ([email protected])Aditi Podder ([email protected])Department of Civil and Environmental EngineeringUniversity of Utah

Questions??

Recoverables from urban waste-streams

Linear metabolsim vs cicrcular metabolism in recovery of useful resources (Wielemaker et al., 2018)

There are two issues in recovery of nutrients• Nutrient Sources• Global nutrient imbalance

Environmental Input of Nutrients

Removing BOD from UWW RemovingN from UWW Utilizing C:N ratio in UWW Harvesting carbon from UWW Harvesting energy from UWW

High Input and Limited Recycling Adds Lots of NUTRIENTS to the Environment

Environmental Imbalance in Nutrients!!

Solid waste

Landfill

Leachate

• Leachate is one of the concentrated urban waste streams• Environmental threat• Complex blend of contaminants• Current approaches rely on “removal”

Landfill Leachate-a waste or a resource

•Lots of nitrogen, carbon and phosphorus•How can we recover and treat using innovative approaches?

Municipal Solid Waste Generation

(a) Municipal waste generation and treatment in the EU Member States, 2015 (in kg per person) (b) Total Municipal solid waste generation and per capita waste generation in United States (USEPA, 2016)

Generation of Municipal Solid Waste is increasing every year with CONSTANT facilities for Solid Waste Management!!

Different components of our approach

Reject water

Leachate

Step 1: Nutrient recovery @ different pHs

Step 2: Granular activated sludge process to remove carbon. Unlike in flocculated activated sludge processes, dense granules will be able to tackle toxics: Alternative: Use anaerobic process to recover carbon

Step 3: Partial nitrification coupled with anaerobic ammonia oxidation to remove remaining nitrogen

Recovery of Ammonia N:P ratio in the mixture of leachate and centrate is GREATER

than 40 Most of the Phosphorus from the mixture can be recovered

from Struvite Precipitation Lots of Ammonia is left in the system to deal with. Ammonia is highly Soluble which makes it difficult for Ion

Exchange Process

• There are several ways to treat and recover the rest of the Ammonia-nitrogen in the system

• Microbial Protein Production Ammonium High quality feed for livestock

• Simultaneous Nitrification-DenitrificationAmmonium Nitrite Nitrate Nitrogen Gas

• Anaerobic Ammonium OxidationAmmonium+ Nitrite Nitrogen Gas Recovery of Ammonia in terms of Microbial Protein leading

towards CIRCULAR ECONOMY(Source: power to PROTEIN)