【作者】 张建梅；

【导师】 林春绵； 唐亮；

【作者基本信息】 浙江工业大学 ， 环境工程， 2009， 硕士

【摘要】 缫丝行业产生的废水含有大量氮、磷等营养物质,易造成水体富营养化,严重影响人类生活和工、农业生产。目前对缫丝废水处理的研究多限于COD_Cr的去除和丝胶的回收利用,缺乏对缫丝废水脱氮除磷的研究。本文根据缫丝行业废水水质特点进行分类治理。首先用酸析法对汰头废水进行预处理,使大部分丝胶蛋白沉淀,然后用SBR工艺进行正交实验,找出SBR工艺运行的最佳条件,研究影响SBR工艺脱氮除磷的主要因素。研究得出如下主要结论:（1）利用正交实验研究酸析法处理汰头废水去除有机物最佳条件是:pH值为4.2、沉淀时间3小时,温度和搅拌时间对去除效能无显著影响,但温度较高和延长搅拌时间,不利于蛋白质的析出。汰头废水COD_Cr、TN、NH₄⁺-N、TP浓度为8997mg/L、971.3mg/L、358.5mg/L、189.2mg/L,通过酸析法处理COD_cr、NH₄⁺-N、TN和TP去除率达77.15%、73.6%、75.63%和74.97%。（2）利用正交实验确定了SBR工艺的最佳运行条件是:厌氧搅拌3小时,第一次曝气6小时,缺氧搅拌3小时,第二次曝气1小时,然后沉淀排泥排水,运行周期为14小时。在最佳运行条件下,当进水COD_cr、TN、TP浓度分别为468mg/L、44.7 mg/L、6.8 mg/L时,出水浓度可以分别达到25.2 mg/L、6.1 mg/L、0.49 mg/L,去除率分别达到94.62%、86.35%、92.79%。（3）温度对SBR系统脱氮除磷有较大影响,在20-35℃,对有机物的去除和脱氮除磷效果较好。pH值等于7.0、温度为30℃,废水COD_Cr、TN、TP浓度为525mg/L、48.3mg/L、7.6mg/L,经SBR法处理后,去除率分别达到92.85%、84.33%、92.75%。（4）进水pH值对COD_Cr、TN、TP的去除率的影响不同,在实验条件范围内,对COD_Cr的去除率基本没有影响、对TP的影响较小,对TN去除率的影响很大,pH在6.5-8.0,SBR工艺有良好的脱氮除磷能力。（5）C/N对COD_Cr的去除基本没有影响,对TN、TP的去除率影响很大。当C/N小于8时,碳源是脱氮除磷的限制性因子,当C/N大于10时,碳源就不再是脱氮除磷的限制性因子了。（6）好氧阶段DO浓度对COD_Cr去除率的影响较小,DO浓度对TP的去除率影响较大,因此要保证COD_Cr、TN、TP均能高效去除时,好氧阶段DO不宜过高,一般为1.5-3mg/L。更多还原

【Abstract】 The wastewater generated in filature industry contains large amounts of nitrogen, phosphorus and other nutrients,could easily lead to eutrophication,seriously affecting human life and industrial and agricultural production.Current researches on filature wastewater treatment were largely confined to the removal of COD_Cr and the recovery of sericin,lacking the systematic study of nitrogen and phosphorus removal.In this paper,filature wastewaters were separated and treated respectively according to their characteristics.First acid-out method was used to treat the high concentration filature wastewater to subside the majority of sericin protein,and then SBR technology was used to treat the filature wastewater.The orthogonal experiments were carried out to find the best operating conditions for SBR process.The major factors affecting nitrogen and phosphorus removal were also investigated..The main conclusions are described as follows:（1） According to the orthogonal experiment results,to remove organic the pre-processing conditions of high concentration filature wastewater by acid-out method are:pH value of 4.2,deposition time of 3 hours.Temperature and stirring time hava no significant impact on the removal of organic,but high temperature and the extension of stirring time are not conducive to precipitation of proteins.The concentrations of filature wastewater are COD_Cr8997 mg/L,TN971.3 mg/L,NH₄⁺-N358.5 mg/L,TP 189.2 mg/L.By acid-out treatment the removal efficiency of COD_Cr, NH₄⁺-N,TN and TP are 77.15%,73.6%,75.63%and 74.97%respectively.（2） The optimal operating conditions for SBR precess were determined by orthogonal experiment:anaerobic stirring 3 hours,the first aeration 6 hours,hypoxia stirring 3 hours,the second aeration 1 hour,and then discharge of water and sludge after precipitation,and one period 14 hours in all.Under the operating conditions, when the influent concentrations of COD_Cr,TN,TP were 468 mg/L,44.7 mg/L,6.8 mg/L,the effluent concentrations would be 25.2mg/L,6.1mg/L,0.49mg/L respectively,and removal rates reached 94.62%,86.35%,92.79%.（3） Temperature has significant impact on nitrogen and phosphorus removal efficiency.At 20-35℃,higher nitrogen and phosphorus removal rates can be reached. Under the conditions of temperature 30℃,pH value 7.0,wastewater concentration of COD_Cr525mg/L,TN48.3mg/L,TP7.6mg/L,the removal rates of COD_Cr,TN,TP reached 92.85%,84.33%,92.75%repectively.（4） The influent pH value has different impact on the COD_Cr,TN,TP removal efficiency.Under the experimental conditions the influent pH had little effect on COD removal efficiency,week effect on TP removal efficiency and stronger effect on TN removal efficiency.SBR process possesses a good capacity of nitrogen and phosphorus removal with pH 6.5-8.0,.（5） C/N has little impact on the removal of COD_Cr,significant influence on TN, TP removal rate however.When the C/N is less than 8,the carbon source is the restrictive factor to nitrogen and phosphorus removal.When the C/N is greater than 10,the carbon source is no more the restrictive factor on nitrogen and phosphorus removal.（6） The DO concentration during aerobic process has less impact on the removal rate of COD_Cr,and greater impact on the removal rate of TP.To ensure the higher removal rates of COD_Cr,TN,TP,the DO concentration of aerobic phase should not be too high,generally 1.5-3mg/L.更多还原