Study on chemical wastewater treatment with many-point-water-inflow biological reaction tank

摘要

The composition of mixed chemical wastewater is more complex and biodegradability of its is bad, biochemical treatment effect should be further improved. Many-point-water-inflow bioreactor used in this experiment, through controlling hydraulic retention time(HRT), concentration of active sludge of the aeration tank, trace element content and so on, gets a better treatment effect. When water temperature is 25°C, HRT is 5h, 10h, 15h, 20h, 25h,COD removal rate is 60.37%, 82.62%, 89.44%, 91.02%,91.07%. According to the iron content of influent, plus 0.5mg/L ferrous sulfate into influent, the removal rate of COD is increased, activated sludge floc of the sedimentation tank is denser and settling. By changing the activated sludge return ratio to change the activated sludge concentration of the bioreactor, experiments shows that the removal rate of organic matter is better with the activated sludge concentration about 4000-5000mg/L. Influent qualities indicate that this biological treatment has good effect on mixed chemical wastewater.