Research On Wastewater Treatment Techniques By Ferric-Carbon Micro-Electrolysis

Water is a very important resource for the existence and development of our human society. Modern industry produces more and more wastewater, and water pollution situations are increasingly more serious than ever before. Industrial wastewater has attracted a great deal of attention because of its high concentration, high toxicity, complex composition and low biodegradability. It is usually necessary to provide partial or complete treatment of sewage before it can be disposed of otherwise it may do great harm to our environment. So a lot of methods are studied to meet this need. Although new, ferric-carbon micro-electrolysis method (FCME) is excellent in wastewater treatment because its good adaptability, excellent treating ability, low costs, long life and easiness to operate and to fix up.Being concerned with the actual situation of chemical industries such as pesticides and printing in our living area, a series of experimental research on FCME in treating organic wastewater has been performed. The finished work can be categoried into the following:1) The capability of FCME in the treatment of mixed pesticides wastewater has been studied. The COD of the pollutants in water can be effectively removed, the removal efficiency is about 42% for 4 hours treatment, and this ratio is not relevant to the COD value of the original wastewater in our experiment scale. High decolorization and deodorization effect is realized. Subsequent treatment methods are studied, and the results show that acidifying plus aeration is the best one, while coagulation sedimentation and oxidation method seems unvalid. The overall COD removal efficiency is between 50%-70%. 2) Synergism of FCME with Fenton method is analyzed and discussed. Their combination is used in the treatment of chlorpyrifos wastewater, petrochemical wastewater and phenol aqueous solution, the optimal conditions are studied respectively, and its treatment limit is around TOC=4mg/L. 3) The concept of "regular packing in micro-electrolysis" is proposed, a novel kind of Fe-C combination in micro-electrolysis made of iron fiber and carbon rod which has high decolorization capability is introduced. Based on the decolorization efficiency, through a series of analytical and comparative experiments, the effect of material used, retention time, aeration on the treatment of 10 aqueous dyes is investigated. The decolorization mechanism of dyes is also discussed. 4) An integrated wastewater treatment equipment incorporating micro-electrolysis technology is designed, the continuous flow of sewage in reactor as a pilot apparatus is realized. Some aspects concerning FCME are discussed in the end, especially its research directions and prospects, it may be very beneficial to the subsequent researchers in this field.