Permanganate Preoxidation Technic Substitutes For The Breakpoint Chlorination Treatment

In this thesis paper, applied researches are carried out and a new sterilization process is advanced which is pre-oxidation by potassium permanganate that can replace traditional break point chlorination. Commencing with removal of manganese present in surface water, researches on pre-oxidation by potassium permanganate are carried out and many phasic achievements are gotten. Based on these, through pilot production, this thesis paper systematically investigates applications of pre-oxidation by potassium permanganate on water treatment, detailedly tests the reliability, stability of the new process, affirms it is feasible that the new process replaces break point chlorination and perfects the parameters of the new process for benefiting the practical application of this process. Through the experiment the following results are concluded.The choice of filling point of potassium permanganate and assorted using with other chemical agents directly affect treatment performances of potassium permanganate and other chemical agents. Potassium permanganate should be added to as far as early and added sequence of agentias should be determined in terms of characteristics of raw water.This process not only can effectively remove iron and manganese present in ground water but also has very good effects on removals of COD, ammonia nitrogen and color and deodorization, which is nothing less than effects of break point chlorination. Water quality satisfies the requirements of national sanitary standards of drinking water. And, this process can enhance performance of coagulation and flocculation precipitation and decrease coagulation agent inlet.Due to the pre-oxidation of potassium permanganate, the content of chloroform significantly decreases. Few chlorine inlets can meet the requirement of sterilization of paper water and the concentration of chlorine can keep a long period. During the experimental period, 5mg/L of chlorine inlet can achieve the similar effects to break point chlorination.According to the water quality of water source at shanghai petrochemical corporation, operational parameters is as follow: potassium permanganate inlet 1.2mg/L, aluminium chloride inlet 25.0mg/L, chlorine inlet 5.0mg/L. The quantities of agentias significantly decrease, nonrecurring investment and the cost of operation is low, this process is not complicated and the managements and controls are very convenient. Furthermore, the per-oxidation process by potassium permanganate is very convenient to adapt to other processes, renovate traditional water treatment processes and be applied new water plants, which adapts to the situation of our country and has significant economic performance and social performance.