混凝法强化去除中药废水中生化抑制物研究

发布时间：2018-06-24 08:18

本文选题：中药废水 + 混凝沉淀　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：中药废水成分复杂,含有包括有毒有害物质在内的种类繁杂的有机物,致使中药废水具有生物毒性强、有机物和悬浮物浓度高、色度大的特点,属难处理的工业废水。单独采用生物法处理一般难以实现达标排放,实际工程中往往采取合适的预处理技术,降低废水污染物负荷的同时,削减废水毒性,改善废水可生化性,为后续生化处理创造良好的条件,提高整体工艺的处理效能,实现达标排放。本文首先初步建立了中药废水毒性测评方法,以毒性衡量废水中生化抑制物水平;其次研究了中药废水常规污染物指标(COD、SS等)和毒性联合削减的混凝沉淀特性,并确定了最佳的混凝条件;最后采用最佳的混凝参数进行了中试研究,研究了混凝沉淀反应器运行效能和稳定性以及混凝预处理工艺对整体工艺运行效能的影响。采用发光细菌法进行中药废水毒性方面的研究,确定了中药废水毒性测试的最佳条件:测试p H为6.0~8.0,暴露时间为15min;以发光抑制率和EC50表征中药废水的毒性,衡量废水中生化抑制物的水平;测定了中药废水对发光菌的毒性EC50=8.12%,毒性级别为极强;建立了拟合度更高的发光抑制率-标准毒物Hg Cl2浓度标准曲线。对比研究聚合硫酸铁(PFS)、聚合氯化铝(PAC)、硫酸铝(AS)、硫酸亚铁(Fe SO4)对中药废水中主要污染物项目COD、SS和毒性的去除效果。当原水p H=6.60,PFS、PAC、AS和Fe SO4投加量分别为500、600、700和800mg/L时,混凝之后毒性由EC50=8.12%分别降低至EC50=33.43%、25.43%、18.31%、18.56%,由此确定了PFS为最佳混凝剂;研究了水力条件、废水初始p H、助凝剂聚丙烯酰胺(PAM)和壳聚糖(CTS)对PFS混凝效果的影响,并采用响应曲面法优化出最佳混凝条件,当初始p H为7.0时,470mg/L PFS与7.5mg/L PAM配合使用对中药废水具有最佳混凝效果,COD、SS去除率分别达到39.3%、98.9%,废水毒性由EC50=8.12%降低至EC50=44.70%,毒性级别由极强削弱至中等。研究了混凝沉淀反应器的中试运行效能,结果表明,混凝沉淀工艺运行效果稳定,具有较强的抗冲击负荷能力,且污染物负荷得到较大幅度削减,常规污染物指标COD、SS、色度和TP去除率分别稳定在30%、90%、95%和85%以上,对毒性发光抑制率削减率保持在20%以上,废水中生化抑制物得到部分削减;评价了生化工艺对废水毒性的去除能力,结果表明,相比厌氧(水解酸化)工艺,好氧工艺在毒性削减方面具有明显优势,但最终出水急性毒性依然超标;混凝沉淀工艺对后续整体工艺的运行具有积极的影响,改善了整体工艺对各污染物项目的去除效果,强化了整体工艺的运行效能,解决了单独采用生化法时最终出水中污染物项COD、TP和急性毒性超标的问题,实现了达标排放。
[Abstract]:The composition of traditional Chinese medicine wastewater is complex and contains complex organic compounds including toxic and harmful substances. The traditional Chinese medicine wastewater has strong biological toxicity, high concentration of organic matter and suspended matter and large chroma, which is difficult to treat industrial wastewater. It is difficult to achieve standard discharge by biological treatment. In practical engineering, it is often used in practical engineering. At the same time, reducing the load of wastewater, reducing the toxicity of wastewater, improving the biodegradability of wastewater, creating good conditions for the subsequent biochemical treatment, improving the efficiency of the whole process and realizing the discharge of the standard, this paper first established the method of evaluating the toxicity of traditional Chinese medicine wastewater to measure the level of biochemical inhibitor in the wastewater. Secondly, the characteristics of coagulation and sedimentation of traditional Chinese medicine wastewater (COD, SS, etc.) and combined toxicity reduction were studied, and the optimum coagulation conditions were determined. Finally, the best coagulation parameters were used to study the operation efficiency and stability of coagulant sedimentation reactor and the operation efficiency of coagulation pretreatment process to the whole process. The toxicity of the traditional Chinese medicine wastewater was studied by the luminescent bacteria method, and the best conditions for the toxicity test of traditional Chinese medicine wastewater were determined: the test p H was 6.0~8.0, the exposure time was 15min, the toxicity of the luminescence inhibition rate and EC50 was used to characterize the toxicity of traditional Chinese Medicine wastewater, the level of biochemical inhibitor in the wastewater was measured, and the toxicity of traditional Chinese medicine wastewater to luminescent bacteria was measured. EC50=8.12%, the toxicity grade is very strong; the higher fitting luminescence inhibition rate - standard poison Hg Cl2 concentration standard curve is set up. Compared with Polyferric sulphate (PFS), polyaluminum chloride (PAC), aluminum sulfate (AS), and ferrous sulfate (Fe SO4), the removal effect of COD, SS and toxicity of the main pollution contaminants in Chinese traditional medicine wastewater. When the dosage of Fe SO4 was 500600700 and 800mg/L respectively, the toxicity was reduced to EC50=33.43%, 25.43%, 18.31%, 18.56%, respectively after coagulation, which determined that PFS was the best coagulant, and the effect of the hydraulic conditions, the initial P H, the coagulant polyacrylamide (PAM) and the chitosan (CTS) on the PFS coagulation effect was studied, and the response curve was used. The optimum coagulation condition was optimized by surface method. When p H was first 7, 470mg/L PFS and 7.5mg/L PAM had the best coagulation effect on traditional Chinese medicine wastewater. The removal rate of COD, SS was 39.3%, 98.9% respectively. The toxicity of waste water was reduced from EC50=8.12% to EC50=44.70%, and the toxicity grade was greatly weakened to medium. The pilot transport of coagulation sedimentation reactor was studied. The results show that the coagulation sedimentation process has a stable operation effect, strong anti impact load capacity, and the pollutant load is greatly reduced. The conventional pollutant index COD, SS, chromaticity and TP removal rate are 30%, 90%, 95% and 85% respectively, and the reduction rate of the toxic luminescence inhibition rate remains above 20%, and the wastewater is inhibited by biochemistry. The results show that the aerobic process has obvious advantages in toxicity reduction compared with anaerobic (hydrolytic acidification) process, but the final acute toxicity of the effluent is still beyond the standard, and the coagulation sedimentation process has a positive effect on the operation of the continued whole process and improved the whole process. The removal effect of body technology on various pollutants has strengthened the operation efficiency of the whole process, and solved the problem of COD, TP and acute toxicity exceeding the standard when the biochemical method was used alone, and achieved the discharge of the standard.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X787

【参考文献】