What is a Bioreactor Landfill?
A bioreactor landfill changes the goal of landfilling from the storage of waste to the treatment of waste. A bioreactor landfill is a system that is isolated from the environment and that enhances the degradation of refuse by microorganisms. Microbial degradation may be promoted by adding certain elements (nutrients, oxygen, or moisture) and controlling other elements (such as temperature or pH). The most widely used and understood method of creating a landfill bioreactor is the recirculation of leachate, since the element that usually limits microbial activity in a landfill is water. The recirculation of leachate increases the moisture content of the refuse in the landfill and, therefore, promotes microbial degradation. If leachate recirculation alone cannot raise the moisture content to levels at which microbial growth is enhanced (40% by weight, minimum), water may need to be added to the waste.
Simply put, it is a waste treatment landfill with technology that accelerates the decomposition of organic wastes in a landfill. This is accomplished by controlling the addition and removal of moisture from the waste mass, the collection and extraction of landfill gas, and in some instances the addition of air. For more information on bioreactors visit the United States EPA Office of Solid Waste, Bioreactor website. Waste Management currently operates ten full-scale waste treatment landfill projects in the U.S. and Canada. We are evaluating the economic and environmental impacts as well as developing the operational knowledge needed for safe and effective implementation. Among our current projects are: • Outer Loop, Louisville, Kentucky This innovative project is part of long term cooperative research and development study performed in conjunction with the USEPA to evaluate bioreactor technologies. The project was honored with the Environmental Excellence Award for Industrial Environme
A bioreactor landfill operates to rapidly transform and degrade organic waste. The increase in waste degradation and stabilization is accomplished through the addition of liquid and air to enhance microbial processes. This bioreactor concept differs from the traditional dry tomb municipal landfill approach. A bioreactor landfill is not just a single design and will correspond to the operational process invoked.
