| Over the past century, the chlorine disinfection of potable water has played a vital role in controlling the water-causing diseases and improving the safety of water microorganism, thus contributing largely to lowering the rate of the water-causing diseases. But with the advent of disinfected by products, the chlorine disinfection lowers the risk of water microorganism, yet raises the risk of water chemicals, which also has some impacts on the safety of potable water. Hence, it is of urgent necessity to study the safety on disinfection technology so as to assure both the safety of water microorganism and lowering chemical risks to the largest extent.As a kind of long-time applied disinfection means, the technology of chloramines disinfection has gradually become one of the research subjects to replace the traditional liquid chlorine disinfection, with regards to its feature of lowering the organic halide in the piped water and maintaining original disinfection properties in the piped system. Owing to so many factors, such as water quality, craft conditions and piped system conditions, the research on its application is not complete and can't meet the need of practical uses in every field.Based on the study of application of chloramines disinfection at home and abroad, local water quality and practices, this paper makes some implications on the relationships between chloramines disinfection and water quality as followed.1. It is more effective to disinfect water by means of "first chloramines, then ammonia" in lowering pollution. Therefore, Chengdu No. Six Potable Factory uses this way to disinfect water. Considering that this way may result more nitrite nitrogen, it really needs to add chlorines regularly before recovery with duration 30 days in summer and 60 days in winter.2. Based on its local water quality of Chengdu No. Six Potable Factory, after purified, water turbid lowering to 0.5 NTU, the amount of adding ammonia reaching 0.3-0.4mg/L, chloramines ration being 4:1 and the total remained chlorine over 1.0mg/L, per hour, its disinfection will meet the international standards in two hours.3. By comparing the two different ways of disinfection, the study shows as the followings:(1) More effective and better disinfection results will be obtained by means of chloramines disinfection ( which is more suitable for medium-long distance pipedsystem ) in the piped system than those by liquid chlorine disinfection.(2) Chloramines disinfection can lower disinfection byproducts greatly on the basis of guaranteeing the safety of microorganisms.(3) Chloramines disinfection can do much better in improving potable water quality and reducing its bad effects than what liquid chlorine disinfection can do.(4) Chloramines disinfection can effectively control the generations of microorganism and has more advantages over liquid chlorine disinfection in reducing the amount of AOC (Assimilability Organic Carbon)in potable water improving its stability of microorganism.4. When the Chloramines disinfection water is combined with the liquid chlorine disinfection water and reaches some stable ratio for a long time, the great reduction of the remained and total chlorines in the piped system will be obtained. (In addition to the above mentioned, this paper also makes the research on the factors which can affect Chloramines disinfection, existing problem, its solutions and comparisons of two ways of disinfection. Furthermore, it makes some prospects for the future work.)...
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