Leachate Management

Sanitary Landfill and Hazardous waste management

1. Prof. M.R.Ezhilkumar
Assistant Professor
Department of Civil Engineering
Sri Krishna College of Engineering and Technology
Coimbatore
[email protected]
IonlyfeelangrywhenIseewaste.
WhenIseepeoplethrowingaway
thingswecoulduse.–Mother
Teresa
1
17CE413
SOLID AND HAZARDOUS
WASTE MANAGEMENT
3.5 –Leachate Management

2. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 2
Learning Outcomes
☼Leachate production
☼Leachate Collection
☼Leachate Treatment
☼Leachate Management
3.5 –Leachate Management

3. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 3
Video Session

4. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 4
Leachate
Infiltrative water percolates through waste materials, results in the leaching of
organic and inorganic compounds (McBeanet al. 1995).
A complex organic waste that changes with time
Problematic components
–Degradable & nondegradableorganics
–Hazardous organics and inorganics
–Ammonia, nitrate, and nitrite
–Suspended solids
–Colorand odor
–Pathogens

5. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 5
Leachate
Leachateistheliquid(orwastewater)thatformswhenwater(rainfall,
groundwater)travelsthroughsolidwaste
Leachatecanmigrateintounderlyinggroundwater,resultingincontamination
Leachatecancontainmanydifferentchemicals,dependingonwhatisinthe
solidwaste

6. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 6
Leachate

7. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 7
Leachate
How is Leachate Produced?
Waste Decomposition
• Phase I
–Aerobic
• Phase II
–Anaerobic
–Facultative
• Phase III
–Methanogenic

8. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 8
Leachate
Leaching Mechanisms
Leaching of inherently soluble materials
Leaching of soluble biodegradation products
Leaching of soluble products of chemical reactions
Washout of fines and colloids
Leachate generation continues for typically 30-40 years following site closure

9. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 9
Leachate
Importance of Leachate Quality and Quantity Determination
Design leachate collection systems
Design leachate treatment facilities
Determine acceptability of offsite treatment
Estimate offsite migration potential

10. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 10
Leachate
Leachate Management Principles
Chemical composition of leachate varies considerably depending on:-
–Waste composition –Site characteristics
–Climatic conditions –Age of landfill
Leachate management strategies must be:-
–Practical –Cost effective
–Flexible –Developed for long term environmental
management

11. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 11
Leachate
Leachate Management Technologies
There is a wide range of leachate management technologies adopted by
Landfill Managers. Technology selection often depends on a number of critical
factors including:
–Composition of leachate
–Type of collection method
–Volume of leachate generated
–Available space on site
–Access to sewer
–Availability of technologies

12. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 12
Leachate
Planning Treatment and Disposal
Estimate leachate flow, Q
–WBM/HELP
–Variations with site age
Estimate leachate contaminant conc., C
–Type
–Variations with age
Identify treatment and disposal options with discharge standards and cost
Select treatment and disposal system
–Introduce uncertainty
–Maintain flexibility

13. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 13
Leachate
Leachate Production Characteristics

14. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 14
Leachate
What Characterizes Leachate?
Phase I
–Brief
–CO2
–H2
Phase II
–Years
–High BOD
• >10,000mg/L
–High BOD:COD
• >0.7
–Low pH
• 5-6
Phase II
–Smells
–High Ammonia
• 500-1000 mg/L
–High Levels
• Fe, Mg, Zn, Ca, Mn
Phase III
Decades (never)
High fatty acids
No O2
CH4
CO2
Stabilized
Low BOD
Low BOD:COD
Phase III
High
Ammonia/Nitrogen
High Levels
Fe, Na, K, Cl2, SO4

15. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 15
Leachate
Factors Affecting Leachate Quality and Quantity
Particle size
Compaction
Waste composition
Site Hydrology
Cover Design
Conditions within Landfill
•Chemical & Biological Activities
•MC %, Temperature, pH, Degree of Stabilization
Waste Age
Landfill design/operation
Sampling procedures
Interaction of leachate with environment

16. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 16
Leachate
What are Trends in Leachate Contamination?

17. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 17
Leachate
Landfill Leachate

18. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 18
Leachate
pH
Influence chemical and biological processes of precipitation, redox, sorption,
methanogenesis
Controlled by volatile acids during acid phase
After methanogenesisbegins, controlled by carbonates and ammonia
Major factor in controlling metal solubility

19. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 19
Leachate
Heavy Metals
May act as inhibitors of biological stabilization process
Water quality concerns
No discernable chronological pattern
Leachate concentration controlled by sulfide, carbonate, chloride, and
phosphate

20. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 20
Leachate
Nitrogen/Phosphorus
Indication of nutrient availability
Phosphorus may be limiting nutrient
Ammonia important buffer
Nitrogen present for long periods of time

21. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 21
Leachate
How do you Remove Leachate from the Landfill?
Drain as much as you can by gravity (liner system and pipes)
Pump from low points
–Penetration through the liner
–Pumps inside landfill

22. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 22
Leachate
Leachate Collection System
Ifleachateflowisinterceptedorimpededbyaliner,thenitshouldberemoved
fromthelandfillbyuseofaleachatecollectionsystem.
Aleachatecollectionsystemisahigh-permeabilitylayerdesignedtotransmit
leachatefromtheliner.

23. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 23
Leachate
Leachate Collection System with Graded Terraces

24. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 24
Leachate
How is Leachate Removed

25. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 25
Leachate
Leachate is then sent to Treatment and/or Storage Facility

26. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 26
Leachate
Leachate Storage
Undergroundstoragetanks
Lagoons
Abovegroundtanks
Threeday’sstorageatpeakannualflow

27. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 27
Leachate
How do you Predict Leachate Generation?
Youmustestimatehowmuchleachateisgeneratedtodesignyourlandfill.
HELP--HydrologicEvaluationofLandfillPerformance
AWaterBalanceModel

28. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 28
Leachate
Notes about HELP Model
Mustassumeanareaandadepth(thereforenotgoodforanopen,operating
landfill)
Manywaystomanipulate
Hydraulicconductivityofwastetohigh

29. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 29
Leachate
Porous cup suction Lysimeterfor the collection of liquid samples
from the landfill

30. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 30
Leachate
Leachate Treatment Systems?
Options
FullOn-SiteTreatment
PartialOn-SiteTreatment
TransportOff-Site
Considerations
oRecirculation
oProximityofSewer
oHaulDistance
oPumpSystemCosts
oWWTPCapacity
oLeachateStrength
Considerations
oLocalSewerUse
Laws
oSewerSurcharges
oSurface Water
Discharge
Standards(On-Site)

31. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 31
Leachate
What are Common Leachate Treatment Types?
AnaerobicorAerobicBiologicalTreatment
Physical&ChemicalTreatment
LeachateRecirculation&LandApplication

32. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 32
Leachate
Anaerobic or Aerobic Biological Treatment
BiologicalTreatment
ChangestheformofOrganicConstituents
RemovesBOD5,SS,NH3-N,Organic-N&Metals
Generateslargequantitiesofbiomass(sludge)
AnaerobicTreatment
Two-StageReactor
FixedFilmFilters
AerobicTreatment
Lagoons
ActivatedSludge
RBC’s
TricklingFilters

33. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 33
Leachate
Anaerobic or Aerobic Biological Treatment
BiologicalTreatment
EssentialifBOD>50mg/L
Expect
•BODremoval
•SSremovalwithsedimentation
•NH3-NandOrg-Nremovalbybiouptakeandnitrification
•Metalremovalbybiosorptionandprecipitationatoxidesandcarbonates
•Priorityorganicsremoval

34. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 34
Leachate
Leachate Management Technologies

35. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 35
Leachate
Physical & Chemical Treatment
Moreappropriatetreatmentasalandfillstabilizes
Polishesbiologicallytreatedleachate
TypesofTreatment
GranularFiltration CarbonAdsorption
ChemicalPrecipitation Ultrafiltration
ReverseOsmosis BreakpointChlorination
AirStripping IonExchange

36. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 36
Leachate
Reed Bed
Removalofheavymetals,BOD,TSS,Nitrogen,&Phosphorus

37. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 37
Leachate
Constructed Wetland
Uses
Polishingtreatment
Completetreatment
Advantages
Relativelyinexpensivetobuild/operate
Associatedwith‘green’technologies
Wetlandscredits
Disadvantages
Largelandrequirement
Coldweather
Mediocreresultsespeciallyfor
completetreatmentsystems

38. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 38
Leachate
Proposed Leachate Treatment

39. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 39
Leachate
Suitability Of Evaporation
CostOfOperation
ExtremelyCostEffective
RelativelyHighInitialCapitalCosts
MinimalOperatingCosts
EffectOfEvaporation
LeachateVolumeReduction
ExtremelyConcentratedSolution
MinimalContaminationLevelReduction
Risks
PondOverflow
Leaks-MonitoringBores
Drowning-PerimeterFencing

40. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 40
Leachate
Suitability Of Evaporation
LocalWeatherConditions
EvaporationSubstantiallyHigherThanPrecipitation
LocalWeatherData
TheoreticalEvaporationGreaterThanActualEvaporation
LeachateComposition
LeachateCompositionAffectsEvaporationRate
SalinityandConcentrationReduceEvaporationRate
DarkColourIncreasesEvaporationRate

41. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 41
Leachate
Suitability Of Evaporation
SiteConstraints
LargeSurfaceAreaRequired
PossibleOdourIssuesHenceBufferZonesRequired
WindDirectionAndIntensity
RegulatoryApproval
PossibleRegulatoryApprovalRequired
LocationandDesignConstraints
OperationalandManagementConstraints

42. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 42
Leachate
Leachate treatment-issues
Highstrengthandmagnitudeofpollutionpotential
Variationfromlandfilltolandfill
Seasonalandtemporalvariationsinquantityandquality
Processesdesignedtotreattheleachatesfromanyounglandfillshouldbemodifiedinthe
futuretotreatoldleachate/toachievechangesineffluentstandards

43. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 43
Leachate
Leachate Recirculation & Land Application
Leachateiscollected&returnedtothetopoflandfill
AcceleratesthestabilizationoforganicmaterialspresentintheMSW
SprayIrrigationorWellInjection
Evapotranspiration

44. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 44
Leachate
Landfill as a Bioreactor Measure of Success
Fasterlandfillstabilization
Increasedairspace
Reducedleachatemanagementcosts
Reducedgasesandodors
Reducedlong-termcarecosts
Possibly,miningtoregeneratecovermaterial-aperpetuallandfill?

45. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 45
Leachate
Leachate Recirculation
Demerits:-
Ponding/localizedaccumulationofleachate
Severelocalizedsubsidence/sideslopestabilityproblems
Othermanagementrequirementduetoexcessleachateproduction
Selectiveattenuationofcontaminantsrecirculation,thusfurthertreatmentrequired
Mass/fluidtransferlimitation

46. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 46
Leachate
Leachate Recirculation
MethodsofRecirculation
Sprayirrigation
Workingfaceapplication
Gravitywell/trench
Injectionwell/trench
Infiltrationponds

47. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 47
Leachate
It is important to consider
Leachatecharacteristics
Itshazardousnature
Dischargealternatives
Regulatorylimits
Operationalneeds
Costs
Conductoftreatabilitystudies

48. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 48
Assessment Time
Review
Question
RecommendasuitablelandfillmethodforCoimbatoreregion
basedonthecompositionofwastegeneratedinthecity.

49. SHWM –Module 3 –SANITARY LANDFILL AND HAZARDOUS WASTE MANAGEMENT Mr.M.R.Ezhilkumar 49