【作者】 刘建伟；

【导师】 诸葛斌；

【作者基本信息】 江南大学 ， 环境工程， 2004， 硕士

【摘要】 以芭蕉芋为原料发酵法生产甘油产生的废水主要为淀粉质原料浸泡废水、发酵废水、提取废水和洗涤废水。除提取废水为高浓度生物难降解废水外,其它可生化性均较好。本论文提出预处理-UASB-SBR组合工艺来处理发酵甘油废水。首先分别采用混凝法、Fenton试剂法和铁屑微电解法对发酵甘油提取废水进行了预处理技术研究,初步确定了最佳预处理方法为Fenton试剂法。提取废水经Fenton试剂法预处理后再与其它废水混合,采用UASB-SBR法进行处理,出水最终实现达标排放。在进行生化处理之前还分别应用LC/ESI-MS和GC/MS技术对提取废水预处理前后的主要有机组分进行了分析,研究提取废水中有机污染物的去除和转化情况,确证Fenton试剂法作为预处理的有效性和进一步生化处理的可行性。论文的主要研究结果如下:1.采用混凝法预处理发酵甘油提取废水,得到的最佳工艺条件为:PAC用量200mg/L,PAM用量6mg/L。此条件下,废水COD去除率为28.2%。 2.采用Fenton试剂法预处理发酵甘油提取废水,得到的最佳工艺条件为:H2O2用量按H2O2/ COD= 2.0投加,绿矾用量按Fe2+/H2O2 =0.3投加,反应时间2 h,H2O2投加次数为2。此条件下,废水COD去除率达70.1%,BOD5/COD值从0.202提高到0.568,可生化性显著提高,有利于后续的生化法处理。3.采用铁屑微电解法预处理发酵甘油提取废水,得到的最佳工艺条件为:选用铸铁屑和活性炭,Fe/C质量比40g:8g,反应时间100min。此条件下,废水COD去除率达66.5%,BOD5/COD值从0.202提高到0.436,废水的可生化性得到改善。4. 通过对三种预处理方法的比较,选择Fenton法作为发酵甘油提取废水的预处理方法。5. 分别应用LC/ESI-MS和GC/MS技术对发酵甘油提取废水预处理前后的主要有机组分进行分析,结果表明:经过预处理,提取废水中的大分子量、结构复杂的物质,变为小分子量、结构简单的物质。6. Fenton试剂法预处理后的提取废水并入淀粉质原料浸泡废水和发酵废水后,中温条件下,利用UASB反应器处理。UASB反应器接种颗粒污泥后,经过约140d的运行,容积负荷由0.5kgCOD/(m3·d)提高到17.80kgCOD/(m3·d),进水COD浓度由1538.5mg/L提高到6894mg/L,沼气容积产气率达3.10 m3/(m3·d),COD去除率为81.6%。结果说明:通过难降解废水的预处理和对厌氧污泥的长时间培养驯化,利用UASB反应器处理发酵甘油<WP=7>废水可以达到较好的处理效果,提取废水Fenton试剂法预处理后的残留基质对厌氧处理无明显抑制性影响。7. 采用SBR法对发酵甘油废水UASB出水和洗涤废水进行处理,确定SBR的运行程序为:瞬时进水;瞬时进水后闲置1h;曝气6h;沉淀1h;排水0.5h;空置1h;总运行周期10.5h。8. Fenton试剂法-UASB-SBR组合工艺处理发酵甘油废水是可行的。发酵甘油提取废水经Fenton试剂法预处理后, COD去除率达70.1%,可生化性显著提高,再并入原料浸泡废水和发酵废水,中温条件下,经UASB稳定处理后,出水COD可降到972.4-1212.5 mg/L,UASB出水再和洗涤废水混合经SBR处理,出水COD可降到100 mg/L以下,NH3-N可降到15mg/L以下,出水可以达标排放。更多还原

【Abstract】 Wastewater from glycerol production by fermentation with Canna edulis Ker comes from the process of drenching raw materials, glycerol extraction process, fermentation process and the process of equipment-washing. Except that from glycerol extraction process, the wastewater from other three processes is easy to be biodegradable. In this study, the combined system with pretreatment, anaerobic biotreatment(upflow anaerobic sludge blanket, UASB)and aerobic biotreatment (sequencing batch reactor, SBR) was developed to treat wastewater from glycerol fermentation. On the basis of experiments of coagulation, Fenton’s reagent oxidation and micro-electrolytic method, the best method of pretreatment of wastewater from glycerol extraction process was obtained. And then mixed by wastewater from other process, it is treated by UASB-SBR process. And the effluent can meet the national discharge standards. Before the wastewater from glycerol extraction process was biotreated, the organic components in it before and after pretreatment was analyzed by the method of LC/ESI-MS and GC/MS respectively, in order to validate the effects of pretreatments of Fenton’s reagent oxidation and possibility of further biotreatment. The major conclusions of this thesis were shown as following:1.The pretreatment of wastewater from glycerol extraction process with the high COD by coagulation were studied . The results show that when PAC and PAM were used as coagulants and their feeding amount are 200 mg/L and 60 mg/L, respectively, and COD removal efficiency is 28.2 percent.2.The pretreatment of wastewater from glycerol extraction process with the high COD by Fenton’s reagent were studied. The best technical conditions were that: the ratio of COD to hydrogen peroxide is 2.0, the ratio of ferrous ion to hydrogen peroxide is 0.3, reaction time is 2 h, the frequency of H2O2 practice was 2. The results show that the COD removal efficiency is to 70.1 percent. The value BOD5/COD increases from 0.202 to 0.568, and the bioactivity of the wastewater is largely raised, and the biodegradability of the wastewater is largely enhanced.3.The pretreatment of wastewater from glycerol extraction process with the high COD by micro-electrolytic method were studied. The best technical conditions are that: the ratio of Fe-carbon is 40:8, reaction time is 100min. The results show that the COD removal efficiency is to 67.4 percent. The value BOD5/COD increases from 0.202 to 0.436, and the bioactivity of the wastewater is raised. 4. Comparing the three methods, Fenton’s reagent oxidation is selected as the best method of <WP=9>pretreatment of wastewater from glycerol extraction process.5. The method of LC/ESI-MS and GC/MS were used respectively to analyze the organic components of the wastewater from glycerol extraction process before and after pretreatment. It demonstrated that through pretreatment, the molecule of organic components became small, and the structures became simple. 6. Wastewater from glycerol extraction process pretreated then was mixed by wastewater from drenching raw materials and fermentation process, and was treated by mesophilic UASB reactor. The results showed that: through 140 days’ operation after inoculation of granular sludge, the volumetric COD loading of the reactor reached from 0.5kgCOD/m3·d to17.80kgCOD/m3·d, the influent COD of UASB reached from 1538.5mg/L to 6894mg/L, the COD removal efficiency was reached 81.6 percent. The results demonstrated that through the pretreatment of non-degradable organic wastewater and long-time cultivating of sludge, inhabiting effect of remained substances was almostly eliminated and had no apparent side-effect on anaerobic digestion.7. SBR was used to treat the mixture of the effluent of UASB reactor and wastewater from the process of equipment-washing. The determinate parameters are: flow-in 1 h, aeration 6h, settling 1h, flow-out 0.5h and unused 1 h, the total periods was 10.5h. 8. It was workable to treat wastewater from glycerol fermentation by the process of Fenton’s reagent oxida更多还原