Anaerobic/aerobic treatment of hazardous waste leachate

Abstract

In the normal operation of a landfill a liquid effluent, leachate, is generated from incorporated liquids mixed with soluble materials disposed within each trench, and rainwater that infiltrates and percolates through these soluble materials. The wastes within a hazardous waste landfill may vary widely from trench to trench thus generating a highly variable composition leachate that is frequently resistant to conventional aerobic biological treatment. Though this hazardous waste leachate has been commonly disposed of by injection on deep disposal wells, the United States Environmental Protection Agency (U.S. EPA) has indicated that this practice may be banned in the near future. In response, Chemical Waste Management, Port Arthur (CWM-PA), has joined with the Gulf Coast Hazardous Substance Research Center (GCHSRC) on a joint project to evaluate anaerobic/aerobic biological treatment of the hazardous waste leachate generated at the Chemical Waste Management, Port Arthur closed landfall. The ongoing anaer obic treatment phase of the project is using a reactor with granular activated carbon (GAC) as a support media. The use of GAC has proven effective in treating synthetic toxic wastes and specific wastes, such as the work of Suidan at the University of Illinois on coal gasification and phenolic wastes. Because the effluent from an anaerobic process is not suited for discharge to a receiving water, an aerobic process, initially using sequencing batch reactors, will be used to provide the final polishing before discharge.