Modified Resin Preparation And Removal Of Residual Chlorine In The Drinking Water Supply Mechanism And Process

In urban supply water system, chlorization disinfection in water is adopted widely, in order to restrain the propagate of pathogenic bacteria, virus and other pathogenic organism once again, water is disinfected some time later, there should have a proper quantity chlorine retaining in water to ensure continuous capacity of killing germs. However, the surplus residual chlorine can affect people's taste and smell, destroy the quality of water. Moreover, in the process of disinfection, chlorine can react with organic matter and produce a series of hydrochloric ether such as chloroform, bromoform, bromodichloromethane, chlorodibromomethane and so on, these matters can cause to some extent cancer to human body. Therefore, it's a valuable task to make a study of disposing residual chlorine of water.In this paper, firstly, a detail analysis, study and discussion of the existing disposing-chlorine method were made, on this condition, a new method based on the way of oxidation and deoxidization was discussed, phosphoramidic acid chelate resin and DOOl cation exchange resin were chosen as framework materials, two kinds of new disposing-chlorine materials could be obtained by loading Fe²⁺ on the skeleton of the materials, the surplus residual chlorine was disposed by taking advantage of chlorine oxidizing Fe²⁺. Because this two materials have a strong capacity of chelateding and exchanging with Fe²⁺, Fe²⁺ is hardly possible to be exchanged by other ions and reentry into water. Thereby, the obvious characteristic of this method is its high selectivity. It will not bring other ions in water in the process of disposing chlorine, it also will not take sequential pollution and can get high quality water. It can completely make the coming-out water coincide with our national drinking water standard, a new disposing-chlorine method is obtained and the technology flow and parameter of disposing-chlorine is determined.In this paper, firstly, the formation of by-product caused by surplus residual chlorine of water and its bad effect on human was discussed, as well as existing method of disposing chlorine was compared and discussed. Secondly, on the ground of analysing and discussing the existing mensurating method, a new analytical photometry was obtained, the standard of the method was simple and the operation was convenient, it made a breakthrough to the existing methods. And then, on the ground of analysing and comparing with the existing disposing-chlorine methods, a new thought and method of disposing chlorine was discussed. Taking experiment as a basic method, the effect of two disposing-chlorine materials under different conditions was discussed in details, such as modification condition, disposing-chlorine condition, disturbing condition, cleansing condition, as well as some preliminary technology craft condition. The experiment showsthat both of the disposing-chlorine materials have a high disposing-chlorine capability, with modified phosphoramidic acid chelate resin being 63mg/g, it's higher than all the existing disposing-chlorine materials, and modified D001 resin being 7mg/g, it's also a high capability disposing-chlorine material. The result shows the absorption of modified phosphoramidic acid chelate resin accords with Freundlich isotherm, as follows in formulation (1), the absorption of modified D001 resin conforms to Langmuir isotherm, as follows in formulation (2).qe=1.6315ce1-7444 (1)qe= 2-97c< (2)l+0.167ceThe other ions in water have little effect on disposing-chlorine process. In the experiment, a minitype adsorption column was used for dynamic technics condition experiment, disposing-chlorine effect under tap water simulating practice situation and different regenerate condition were discussed. Furthermore, the preliminary technology design was given in the paper according to experiment results. Lastly, some fundamental principle in the process of disposing-chlorine was discussed, which include the following part: the basic theory of adsorption, adsorption isothermal equation, the process of adsorption and exchanging in the column as well as its mathematical model. In addition, a theoretic analysis of the experiment data were made in order to make the best practical mode and parameter.Study in this paper shows that the method based on the mode of oxidation and deoxidization which we put forward has obvious advantages, this method has a high disposing-chlorine capability, it is also highly chlorine selective, other ions in water have little interference to disposing-chlorine effects, it can dispose the surplus residual chlorine in water to below 0.5mg/L and coincide with our national drinking water standard. For technology consideration, this method loads the disposing-chlorine material in a column and takes the way of solid-liquid separation, it is easy to handle and hardly take any sequential pollution. It is a kind of prospective method in the disposing-chlorine of drinking water and industry wastewater.