APPLICABILITY TEST FOR COMBINED BIOLOGICAL-CHEMICAL TREATMENT OF WASTEWATERS CONTAINING BIOREFRACTORY COMPOUNDS

A fast and easy test procedure was developed to check if a wastewater containing biorefractory substances can be efficiently treated in a co mbined biological-chemical process. Efficient treatment is characteriz ed by a minimum use of expensive chemical oxidant, e.g. ozone, for a s pecified removal. The degree of removal of DOC and COD can be obtained characterizing the general feasibility of the combined treatment. Add itionally, the approximate amount of ozone needed for a specified remo val of DOC (Delta O-3/Delta DOC)(all) is obtained allowing preliminary cost estimation. The test procedure used a barometric BOD5 method for the biological removal of biodegradable compounds and simple batch oz onation experiments to oxidize organic compounds. Wastewater with high ammonia content was initially treated in nitrifying fluidized bed bio reactor. The established procedure was successfully tested with the mo del substance nz-chloronitrobenzene (mCNB) and applied to landfill lea chate. (C) 1997 Elsevier Science Ltd.