Understanding the effects of ozonation on a combined municipal/industrial secondary effluent

摘要

Recent studies have reported the potential for the ozonation process to increase the biodegradability of organic material present in wastewater that has undergone secondary treatment. A variety of parameters have been used to indicate this increase in biodegradability. The most common measure continues to be the five-day carbonaceous biochemical oxygen demand (CBOD_5). Increases in CBOD_5 have been believed to signify increased biodegradability. However, the CBOD_5 test as an indicator of biodegradability is subject to possible shortcomings or misinterpretations. For example, CBOD_5 involves the measurement of oxygen uptake at only one point (five days) aong a curve of oxygen uptake (the CBOD versus time curve) that consists of many points. Therefore, it would seem that a more accurate evaluation of the effects of ozonation on biodegradability might be gained through the study of CBOD exertion over time for ozonated and unozonated treated effluents.