Study on the New Technology of Coal Chemical Wastewater Treatment
|School||North China Electric Power University|
|Keywords||coal chemical wastewater coagulation precipitation of MAP UV/Fenton reagent titanium dioxide photocatalysis|
The paper adopted a variety of methods to deal with coal chemical wastewater on the found of analyzing domestic and foreign status quo. It determined that coagulation + MAP precipitation was the pretreatment on wastewater and ascertained the optimum conditions. UV/Fenton reagent, photocatalysis of nanometer TiO2 power （low-pressure/ high-pressure）, UV/Fenton reagent + photocatalysis of nanometer TiO2 power （high- pressure） were used for further treatment on the effluent and ascertained the optimum conditions respectively through experiment. In optimum conditions, the removal efficiencies of COD, BOD5, volatile phenol, ammonia, cyanide and color were 85.82%, 78.91%, 74.88%, 96.15%, 33.94% and 99.50% respectively by UV/Fenton reagent, the value of BOD5/COD increased from 0.35 to 0.58, above guide lines were 78.82%, 67.33%, 69.50%, 95.83%, 77.19% and 99.00% respectively by photocatalysis of nanometer TiO2 power（low-pressure）, the value of BOD5/COD increased to 0.54, above guide lines were 76.79%, 67.51%, 69.50%, 93.08%, 72.44% and 98.00% respectively by photocatalysis of nanometer TiO2 power（high-pressure）, the value of BOD5/COD increased to 0.49, above guide lines were 90.91%, 84.42%, 74.88%, 96.15%, 83.94%and 99.80% respectively by UV/Fenton reagent + photocatalysis of nanometer TiO2 power（high-pressure）, the value of BOD5/COD increased to 0.60. The condition of organic pollutants decomposition in wastewater was discussed by high performance liquid chromatography. The paper researched the inactivation and regeneration of nanometer TiO2 power and analyzed the mechanism of these technologies and estimated the economic benefits. It also finalized the process of coagulation + MAP precipitation- UV/Fenton reagent as the best project on treating coal chemical wastewater. The contents of COD, BOD5, ammonia nitrogen, volatile phenol, cyanide and color reduced to 191.79mg/L, 111.24 mg/L, 14.74 mg/L, 3.6 mg/L, 3.62 mg/L and 25 times respectively by this process, the biochemical properties was advanced effectively.