The Researchment Of Chloramine Disinfection With Chengdu Water Supply

Being a disinfectant technique, chloramine disinfection has been used for a long time. Because it can restrain the produce of TTMS and maintain residual disinfections in long-distance conveying tubes. It has been studied to instead of chlorizating disinfection. But some problems bring by original water and the different conditions of conveying tubes affect the research on chloramines disinfection. The research of the adaptability of it aren't enough to fulfil the practical needs.After analyzed the investigations of disinfection techniques, Some pertinence experiments have been carried on in the laboratory and then in the produce line, according some affects as follows: the status of the product techniques. The status of original water and conveying tubes in Chengdu. The craftwork of chloroamine disinfection . the relation of the doses of chloroamine disinfector and the time to exterminate bacteria with that doses. The transferabilities of disinfectant outgrowths. The transformations admixed with chloroamine disinfectant water and chlorizating disinfectant water in conveying tubes have been particular analyzed. Mostly work and conclusions as follows:(一) Using simulative test and crosswise test, changing some parameters such as the sequence and proportion of chloroamine affiliated. The conditions of original water. Contact time and PH etc. ,comparing the contents of outgrowth disinfection. CT value and the stability of residual disinfector, some results were given:a) When the ammonia-N is more than 0.3 mg/L, and in the proportion of about 4:1 between chlorin and ammonia, two-hours' contact time later, and the total-chlorin is more than 0.8 mg/L still, the disinfection effect of national standard request can be achieved by chloroamine disinfection.b) chloroamine is very stable in water. The residual disinfectors in long-distance conveying tubes still efficiency by chloroamine disinfectant technique. In water, preliminary consumable doses 1-chloroamine are evidently lessen than those of free chloridate. To control the product line is also easy.c)Using chloroamine technique, the determining factor affected the contents of TTMS and halogen acetic is pre- chlorination. Without pre- chlorination, the outgrowths of chlorizating disinfection will greatly reduce. But the doses of disinfection have little effect on controlling filtered water.(二) Using simulative test and onthogonal test to analyze the theories of folded point reactions of chloroamine disinfectant water and the mixed reactions of conveying tubes water by different disinfectant technique.a) When organic contaminations of original water reach some degree, the reactions of some organic nitrogenous and activated chlorine in original water and the transfoms between organic nitrogenous and ammonia-N will disturb the produce and stability of 1-chlonoamino. The curve got by the sutra folded point chlorination theory will have greatly changes.b) When chloramine disinfectant water and free chloridate disinfectant water mixed at specifically condition, several subsidiary reactions which will produce Nitrogen will process. The balanced constants of reactions have relation with some parameters, for example the proportionality of Cl2: N PH value and contact time. At the same time, the stability of disinfector will rapidly decrease.c) Chloroamine disinfection can evidently restrain the produce of TTMS and halogen acetic acid in conveying tubes. With the prolong of contact time, the increment scope of TTMS and halogen acetic acid will decrease.d) Comparing to chlorination, chloroamine disinfection is a better way in reducing the mutations of the objects in drinking water. That is to say, chloroamine disinfection can better reduce the disinfectant outgrowths in drinking water. The total production of AOC also can be well restrained by this way. And the state of the livings in drinking water by chloroamine disinfection is more stably than that in drinking water by chlorination.