Treatability Studies of Pesticide Manufacturing Wastewaters: Dazomet

摘要

The report gives results of laboratory studies of the treatability of manufacturing wastewater from synthesis of the pesticide, dazomet. A tiered approach was taken: the least costly and most available treatments were investigated first. Effluent from the manufacture of dazomet was tested for treatability by activated sludge systems when diluted to 1:100, 1:500, and 1:1000 in municipal wastewater. At 1:100, dazomet showed greater than 95% reduction after biological treatment; however, effluent COD levels were unacceptably high at an average of 160 mg/liter. At 1:500, effluent COD was much closer to the control effluent; however, nitrification of ammonia was severely hampered. At 1:1000, dazomet wastewater had a variable effect on nitrification while effluent COD levels were close to those of controls. It is recommended that dazomet wastewater be diluted to at least 1:1000 in municipal wastewater to minimize the negative effects on the nitrification of ammonia during the activated sludge treatment process.