L8 - Landfills

Name 3 types of landfills

Name 3 types of landfills

Inert waste, other waste, hazardous waste

Layers in landfill for inert waste

Topsoil, waste, mineral drainage, geological barrier

3 operational areas in inert landfill

Entrance, storage, working area

What should to material undergo before entering a NON HAZARDOUS landfill?

Pre treatment

Layers in non hazardous landfill?

Gas collection manifold, gas extraction wells, waste, leachate recovery

2 basic parts of the landfill structure

sealing layers, drainage system

Rules the operators must abide with landfill

rules, permit, 30 yrs of aftercare, monitor according to rules and permits

How many times per year to monitor groundwater?

3x/yr

How many times per year to monitor leakage?

4x/yr

How many times per year to monitor surface water?

2x/yr

How many times per year to monitor gas?

2x/yr

How many times per year to monitor settling?

1x/yr

Technical reclamation

Geotextiles, gutter and buffer layer

Biological reclamation

soil, vegetation,

What is the gas in landfills made up of 99%?

CO2 and methane

How is landfill gas generated?

Decomposition of waste

what is done with the gas from the landfill?

energy recovery

3 types of bioreactors

Aerobic, anaerobic, hybrid

How do aerobic bioreactors work?

O2 is pumped inside the landfill, decomposition accelerated, toxicity minimised

How do anaerobic bioreactors work?

leachate circulated, methane production is higher than normal. Methane is used more efficiently and the landfill doesn’t need to be monitored for such a long time for methane production.

How do hybrid bioreactors work?

upper layers are subjected to aerobic-anaerobic conditions, speeding up decomposition, methane is produced in the lower part

Advantages of bioreactor landfills?

Stabilise in shorter time, revenue from gas, lower toxicity of waste, reduced handling cost