The final capping method in landfill and landfill gas feed back system in its final cap

摘要

PURPOSE: A method for finally covering the waste landfill with soil and a landfill gas recycling system within the finally covered land are provided, for preventing the drying shrinkage due to the temperature variation between the outside of the covered land and the inside of the landfill, the freezing melting due to the extreme difference of temperature, and the vertical crack due to the generation and change of heat stress in the inside of a barrier layer. CONSTITUTION: The final covered land comprises a gas venting layer above the waste layer; a barrier layer, a drainage layer, a filter layer and a top soil layer on the gas venting layer; and at least one insulating layer above or below of the barrier layer. The insulating layer is made of the materials whose heat conductivity is 0.5 or less W/mK, specifically at least one material selected from rockwool, urethane, foaming polyethylene, vacuum extruding foaming polystyrene and foaming polystyrene, and at least one material selected from rice halls, sawdust, wood chip and rubber particle.