摘要本文研究了聚二甲基二烯丙基氯化铵(PDMDAAC)在微污染原水处理制饮用水用氯气消毒过程中,产生消毒副产物亚硝基二甲胺(NDMA)的可能性及机理。对用氯胺模拟加氯消毒条件下与PDMDAAC的反应过程,考察pH,反应温度,接触时间及PDMDAAC投加量对NDMA的生成反应的影响此外,借助文献,通过反应结束后二甲胺(DMA)浓度的测量分析对NDMA的生成机理做了初步解释。结果表明:PDMDAAC会与氯胺生成致癌物质NDMA;当氯胺浓度固定时,PDMDAAC投加量越大,NDMA和DMA生成量都呈现先增后降的趋势且在投料比为PDMDAAC:一氯胺=1:1。25时达到最高值;其他条件不变时,随着接触时间的进行,NDMA生成量也随着增加;在pH为5-9范围内,随着pH的增大,NDMA与DMA量都先增后减且在pH为8时达到最大值;反应体系温度的增高,NDMA生成量在30℃时达到最大值然后减少,而DMA量却一直增加。上述结果为进一步研究动力学及深入探究NDMA生成规律打下良好基础。78115
毕业论文关键词:聚二甲基二烯丙基氯化铵 氯胺 亚硝基二甲胺 微污染原水 可能性
毕业设计说明书外文摘要
Title Preliminary study on disinfection by-products of PDMDAAC
Abstract The possibility and mechanism of forming nitrosodimethylamine (NDMA) which is the disinfection byproducts of polydiallyldimethyl ammonium chloride (PDMDAAC) produces in the production of drinking water using tiny polluted raw water and chlorine were researched 。Under the simulation condition of reaction of chloramine and PDMDAAC, the effects of pH, reaction temperature, contact time and dosage of PDMDAAC on the reaction were investigated。 In addition, with the help of literature and measure of concentration of dimethylamine (DMA) at the end of the reactionthe formation mechanism of NDMA was preliminary explained 。The results showed that: PDMDAAC could react with chloramine to generate the carcinogen NDMA; When the concentration of chloraine was invariant, the generation amount of NDMA and DMA increased with the dosage of PDMDAAC first and then descended there was the biggest generation amount on the feed ratio of PDMDAAC: monochloramine = 1: 1。25;When the other conditions were fixed the NDMA generation amount increased with time;within the pH range of 5-9, both the generation amount of NDMA and DMA was increased with the increase of the pH, and they became their marxium values when pH reached 8 ; as reaction temperature of the system increased, the impact of NDMA formation amount increased and then reached the marxium at the 30℃, however the concentration of DMA increased consistently。 These above obtained results layed a good foundation for further study of kinetics and regulations。
Keywords PDMDAAC chloramine NDMA tiny polluted raw water possibility
1 绪论 1
1。1 水处理消毒现状 1
1。2 亚硝基二甲胺(NDMA)研究现状 1
1。3 PDMDAAC作混凝剂在消毒过程中生成NDMA的研究现状及存在问题 4
1。4 本文研究的内容及意义 5
2 实验部分 6
2。1 实验方案设计 6
2。1。1 方案设计基本思路 6
2。1。2 研究路线框图 6
2。2 实验仪器和实验试剂 7
2。3 实验步骤