Acute Toxicity And Chemical Component With The Change Of Treatment Processes For Three Types Of Industrial Wastewater

In our study, the acute toxicity of three industrial wastewaters (petrochemical wastewater, pigment wastewater and pharmaceutical wastewater) was investigated using luminous bacteria. Chemical compounds of the three types of industrial wastewaters were analyzed by solid phase extraction, liquid-liquid extraction and GC-MS. Besides, toxicity identification evaluations (TIEs) of pharmaceutical wastewater influent were conducted using luminous bacteria.Firstly, the acute toxicity effect of three industrial wastewaters (petrochemical wastewater, pigment wastewater and pharmaceutical wastewater) on luminous bacteria was investigated. The results showed that, the toxicity removal by treatment processes was different for three wastewaters. The petrochemical wastewater was treated by A/O treatment process, pigment wastewater was treated by A2/O treatment process and pharmaceutical wastewater was treated by hydrolysis-aerobic treatment process. The results showed that, the toxicity of petrochemical and pharmaceutical wastewaters were gradually removed by treatment processes. But for pigment wastewater, the toxicity in anoxic tank was the highest, followed by anaerobic tank and aerobic tank. Acute toxicity was not detected for the three effluents.Secondly, the chemical compositions in three industrial wastewaters as long as the change of organic matter after each treatment process were analyzed. The results showed that, mostly organic compounds were removed after treatment while some small molecules were generated.Lastly, toxicity identification evaluations (TIEs) of pharmaceutical wastewater were conducted using luminous bacteria. The results showed that, Cu (Ⅱ) was identified as major toxicant in the raw wastewater. Inorganic oxides (nitrate and nitrite) were also responsible for part toxicity of wastewater.