This document discusses methods for treating landfill leachate. Leachate is produced as water percolates through waste in a landfill. It contains high levels of organic and inorganic contaminants. The main goals of leachate treatment are to reduce environmental impacts and meet regulatory discharge standards. Common treatment methods include biological processes like aerobic and anaerobic treatment, as well as physical/chemical processes such as coagulation, flocculation, adsorption, and membrane filtration. Often, a combination of treatment methods is needed to sufficiently reduce contaminants in leachate before discharge or reuse.

1. LANDFILLL LEACHATE TREATMENT
METHODS
M.Eng Environmental Engineering
Carleton University

2. OVERVIEW
• Leachate Generation
• Leachate Management (Why? and How?)
• Treatment Methods
• Future Prospects

4. LEACHATE COMPOSITION

5. LEACHATE MANAGEMENT
 Objective
 Eliminate environmental impacts
 Satisfy regulatory norms for leachate discharge. (50-200 mg/L COD)
 Methods
Leachate recycling
Discharge into municipal wastewater systems
Leachate treatment and disposal

6. TREATMENT TARGETS

7. Treatment Methods
Biological Treatment
• Aerobic Treatment
• Anaerobic Treatment
Physical / Chemical Treatment
• Floatation
• Coagulation
• Adsorption
• Membrane Filtration

8. BIOLOGICAL TREATMENT

9. AEROBIC TREATMENT
Suspended Growth Systems
 Lagoons
 Activated Sludge Processes
 Sequencing Batch Reactors
Attached Growth Systems
 Trickling Filters
 Moving Bed Biofilm Reactors

10. AEROBIC TREATMENT

11. ANAEROBIC TREATMENT
Suspended Growth Systems
 Digesters ( UASB,EGSB,DSF )
Attached Growth Systems
 Anaerobic Filter
 Hybrid Bed Filter

13. PHYSICAL / CHEMICAL
TREATMENT

14. FLOATATION
Sludge Out

15. COAGULATION
 Advantages
Aluminum sulfate, Ferrous sulfate, Ferric chloride and
Ferric chloro-sulfate are commonly used coagulants.
Effective for organic compounds and heavy metals.
 Disadvantages
Consistent sludge volume is produced
 Increase in concentration of Aluminum or Iron, in the liquid
phase, may be observed
High pH has to be maintained.

16. COAGULATION

17. ADSORPTION
 Advantages
 Design and operating adsorption columns are easy
 Availability materials which can be used as adsorbents
 (coconut shells, charcoal, zeolite, incinerator ash)
 High removal efficiency of > 90% COD
 Disadvantages
 Constant regeneration of activated carbon
 Disposal of used carbon
 Cost of GAC & PAC

18. ADSORPTION

19. MEMBRANE FILTRATION
Microfiltration (35-40% COD removal)
Ultrafiltration (50-70 % COD removal)
Nanofiltration (70-90 % COD removal)
Reverse osmosis ( > 95 % COD removal)

20. MEMBRANE FILTRATION

21. CONCLUSION
• A combination of methods need to be used to meet
discharge standards.
• Activated carbon absorption and reverse osmosis seem to
be the best solutions.
• Nano particles which can target
specific contaminants can be a
solution.