is a process in which water and air are circulated into a specially designed landfill
, in order to cause accelerated biological decomposition
of the waste material. The intention for this type of landfill operation is to maximise the generation of biogas
, which is captured using a network of perforated pipes and burnt to generate electricity. Another desired outcome is the rapid stabilisation of organic waste material (in order to minimise the length of time required to manage the landfill site, or to make use of the decomposed material as compost
There are two types of bioreactor landfills. Aerobic
(with oxygen) where liquid and air are circulated through the landfill, which increases normal composting type decomposition of the organic material.
Anaerobic (without oxygen) is the other method, where adding and recirculating liquids, decomposition is accelerated under anaerobic conditions, increasing the production of landfill gas by 2 to 10 times, approximately half of which is methane. The result is to shift substantial volumes of methane production, which otherwise would not occur for decades hence, to the present. This increase in methane production typically is used in electricity production at an economically better return than a typical sanitary landfill.
is up to 21 times more powerful as a greenhouse gas
than carbon dioxide
. The proper design of a bioreactor landfill should include an efficient landfill gas collection system to prevent near-term increased emissions of methane into the atmosphere.
(1)67 Fed. Reg.100, at pp. 36463 and 36465 (May 22, 2002).
(2)I.P.C.C., Climate Change 2001: The Scientific Basis (2002), p. 38.
(3) James Hansen, “Dangerous human-made interference with climate,” 7 Atmos. Chem. Phys. 2287-2312 (2007).