Performance and Modeling of an Up-flow Anaerobic Sludge Blanket(UASB) Reactor for Treating High Salinity Wastewater from Heavy Oil Production

In this study,an up-flow anaerobic sludge blanket(UASB) reactor was applied to treat the high salinity wastewater from heavy oil production process.At a HRT of ≥24 h,the COD removal reached as high as 65.08% at an influent COD ranging from 350mg/L to 640mg/L.An average of 74.33% oil reduction was also achieved in the UASB reactor at an initial oil concentration between 112mg/L and 205mg/L.These results indicated that this heavy oil production related wastewater could be degraded efficiently in the UASB reactor.Granular sludge was formed in this reactor.In addition,two models,built on the back propagation neural network(BPNN) theory and linear regression techniques were developed for the simulation of the UASB system performance in the oily wastewater biodegradation.The average error of COD and oil removal was-0.65% and 0.84%,respectively.The results indicated that the models built on the BPNN theory were wellfitted to the detected data,and were able to simulate and predict the removal of COD and oil by the UASB reactor.

Effect of Sodium Ion Concentration on Hydrogen Production from Sucrose by Anaerobic Hydrogen-producing Granular Sludge

This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L^-1（Na^＋）, on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the optimum sodium ion concentration [1000-2000mg·L^-1（Na^＋）] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6-413.1mg·L^-1.h^-1, 28.04-28.97ml·g^-1, 7.52-7.83ml·g^-1.h^-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g^-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.

Effect of Sodium Ion Concentration on Hydrogen Production from Sucrose by Anaerobic Hydrogen-producing Granular Sludge

This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the opti- mum sodium ion concentration [1000—2000mg·L-1(Na+)] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6— 413.1mg·L-1·h-1, 28.04—28.97ml·g-1, 7.52—7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.

UASB-两级A/O-混凝工艺处理生猪养殖污水工程实例

针对某规模生猪养殖场污水成分复杂、污染物浓度高、可生化性较好等水质特征,设计采用预处理-UASB-两级A/O-混凝沉淀-多介质过滤-消毒组合工艺进行处理,介绍了工艺流程及主要设计参数,考察并分析了组合工艺对生猪养殖污水的处理效果。工程运行结果表明,该工艺处理效率高,出水稳定,主要污染物指标均达到GB 8978—1996《污水综合排放标准》中的一级标准,出水可用于农田灌溉。

UASB和MBR组合工艺处理生活垃圾焚烧发电厂渗滤液的研究

上升式厌氧污泥床(Upward Anaerobic Sludge Bed,UASB)和膜生物反应器(Membrane Bio-Reactor,MBR)是目前较为流行的渗滤液处理技术,其组合工艺可有效处理渗滤液。生活垃圾焚烧发电厂可以综合运用两种技术,提升渗滤液处理能力,降低渗滤液对环境的危害。本文结合生活垃圾焚烧发电厂渗滤液产生量与设计进出水水质,设计渗滤液处理工艺,确定关键构筑物和设备参数,然后开展应用案例分析,验证渗滤液处理效果。经现场测试,UASB和MBR组合工艺可有效降低渗滤液的氨氮浓度,明显改善出水水质。

Anaerobic treatment of wastewater containing methanol in up-flow anaerobic sludge bed (UASB) reactor

The direct conversion of methanol into methane is the main process in anaerobic treatment of methanol containing wastewater.However,acetic acid can also be produced from methanol theoretically,which may probably result in an abrupt pH drop and deteriorate the anaerobic process.Therefore,it is interesting to know what would really happen in an anaerobic reactor treating methanol wastewater.In this study,an up-flow anaerobic sludge bed(UASB)reactor treating methanol wastewater was operated.The chemical oxygen demand(COD),acetic acid and pH of the effluent were monitored at different loadings and influent alkalinity.The results showed that the anaerobic reactor could be operated steadily at as low as 119 mg/L of influent alkalinity and high organic loading rate with no obvious pH drops.Volatile fatty acids accumulation was not observed even at strong shock loadings.The microorganisms in the sludge at the end of the test became homogeneous in morphology,which were mainly spherical or spheroidal in shape.

气浮+UASB+两级AO组合工艺对肠衣废水处理的工程应用

江苏省某生物科技有限公司肠衣废水处理站一期设计处理规模为1250 m^(3)/d,主体工艺采用气浮+上流式厌氧污泥床反应器(UASB)+两级AO组合工艺,出水水质要求达到《污水排入城镇下水道水质标准》(GB/T 31962—2015)的A级标准。工程实践结果表明,该工艺各个功能单元运行状态良好、出水水质稳定达标,出水COD_(Cr)、TN、氨氮、TP平均质量浓度分别为198、22、1.0、5.7 mg/L,检测指标满足出水水质要求,其中预处理单元有效降低废水污染物负荷在52.2%及以上。文中介绍了肠衣废水处理系统的工艺流程、主要构筑物和设备参数,并对运行成本进行了总结,可供同类工程设计参考。

Feasibility assessment of up-flow anaerobic sludge blanket treatment of sulfamethoxazole pharmaceutical wastewater

Treatment of sulfamethoxazole pharmaceutical wastewater is a big challenge.In this study,a series of anaerobic evaluation tests on pharmaceutical wastewater from different operating units was conducted to evaluate the feasibility of using anaerobic digestion,and the results indicated that the key refractory factor for anaerobic treatment of this wastewater was the high sulfate concentration.A laboratory-scale up-flow anaerobic sludge blanket(UASB)reactor was operated for 195 days to investigate the effects of the influent chemical oxygen demand(COD),organic loading rate(OLR),and COD/SO_(4)^(2-) ratio on the biodegradation of sulfamethoxazole in pharmaceutical wastewater and the process performance.The electron flow indicated that methanogenesis was still the dominant reaction although sulfidogenesis was enhanced with a stepwise decrease in the influent COD/SO_(4)^(2-) ratio.For the treated sulfamethoxazole pharmaceutical wastewater,a COD of 4983 mg/L(diluted by 50%),OLR of 2.5 kg COD/(m^(3)·d),and COD/SO_(4)^(2-) ratio of more than 5 were suitable for practical applications.The recovery performance indicated that the system could resume operation quickly even if production was halted for a few days.

pH对UASB运行效能及产甲烷互营菌群的影响

研究产甲烷互营菌群对pH变化的响应,对于寻求提高有机废水厌氧生物处理效能的策略具有重要意义.以处理制糖废水的升流式厌氧污泥床(UASB)反应器的运行为基础,考察不同pH对反应器运行效能及产甲烷互营菌群的影响.结果表明,在进水COD 20 000 mg.L-1、HRT 8 h的条件下,当进水pH分阶段由6.9降至5.4时,UASB系统的pH随之从6.8～7.4下降至5.7～6.7,导致COD去除率降低了23.3%,出水中残留丙酸提高了3.9倍.聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)分析结果表明,产氢产乙酸菌群在UASB中的多样性显著低于产甲烷菌群,其分布和优势度受pH降低的影响显著.以Eub 19(Pelotomaculum)为代表的食丙酸产氢产乙酸菌在偏酸环境中的优势度明显减弱,而食乙酸产甲烷菌及部分食氢产甲烷菌对pH下降响应并不显著,且随着pH下降,耐酸的食氢产甲烷菌Methanobacterium ferruginis和Uncultured Methanobrevibacter的优势度逐渐增强.由此可见,与产甲烷菌群相比,UASB系统中的产氢产乙酸菌群对pH的变化更加敏感.

UASB处理头孢类抗生素制药废水的试验研究

采用UASB厌氧反应器在中温条件下处理头孢类抗生素制药废水。结果表明:当反应器稳定运行后,进水CODCr的质量浓度为14 300 mg/L,容积负荷可达到14.3 kg/(m3.d),CODCr的去除率能够稳定在85%左右,出水CODCr的质量浓度在2 500 mg/L以下,出水VFA的质量浓度在3 mmol/L左右,产气量达到17 L/d左右。试验取得了良好的处理效果,为利用厌氧技术处理头孢类抗生素废水提供了设计依据。

UASB—SBR工艺处理阿维菌素废水

采用UASB—SBR组合工艺处理阿维菌素废水,考察了UASB反应器和SBR反应器中COD的去除效果。UASB反应器稳定运行阶段,当进水COD为9 210 mg/L、容积负荷为9.21 kg/(m3.d)时,COD去除率稳定在85%左右。SBR反应器稳定运行阶段,当进水COD为1 010 mg/L、容积负荷为1.01 kg/(m3.d)时,出水COD在300 mg/L以下,COD去除率约为75%。出水COD达到GB8978—1996《污水综合排放标准》的二级排放标准。

EGSB反应器与UASB反应器处理有机废水的性能比较研究

EGSB与UASB反应器中温(35℃)研究表明:EGSB反应器处理高浓度有机废水时,具有启动周期短、容积负荷率提高快、COD去除率高等优点,对操作条件(如温度和pH值)的突变有较好的耐冲击能力;在处理较低浓度废水时,两种反应器性能差异更加明显。

UASB处理离子交换树脂生产废水的试验研究

本研究主要介绍，尝试采用UASB（Upflow Anaerobic Sludge Bed）反应器厌氧工艺处理某离子交换树脂生产废水试验。研究表明，在中温（37℃±1）环境下，容积负荷在6．0-7．0kgCODcr·m^-3·d^-1时，CODcr去除率维持在80％左右，运行稳定。本试验取得的试验效果，为以后的利用厌氧技术处理离子交换树脂生产废水提供了重要依据。

低温下UASB反应器处理低浓度城市污水的可行性研究

应用恒流泵进水,控制进水COD浓度,流量不变,研究低温(7-30℃)下COD去除率、厌氧微生物的宏观活性、挥发性脂肪酸(VFA)等变化情况。结果表明,在低温下保持温度在16.2-25℃且不发生突变、反应器pH值在6.6-8.2,即能保证UASB的稳定高效运行。其中产甲烷菌能保持比较高的活性,COD去除率稳定在65%以上,同时也证明了运用UASB反应器处理低浓度有机废水是可行的。

ABR+UASB+SBR法处理养牛废水的工程应用

介绍了采用ABR+UASB+SBR法为主体工艺处理养牛废水的工程实例,并对运行效果进行了分析。从运行结果来看,养牛废水采用该工艺是成功的,该工艺适应性强,运行效果稳定,出水水质各项指标均可达到《畜禽养殖业污染物排放标准》(GB18596-2001)中的排放标准。

UASB技术在啤酒废水处理改造中的应用

通过在某啤酒厂的废水处理流程中添加UASB处理单元,形成了UASB-水解-A/O的处理体系。运行结果表明,该工艺处理效果稳定,耐冲击负荷能力强,出水水质好。对于进水COD为2400 mg/L,BOD5为1300 mg/L,SS为400 mg/L的啤酒废水,处理出水各项指标均能达到《啤酒工业污染物排放标准》(GB19821—2005)一级标准的要求,其中COD≤50 mg/L,改造后去除单位COD能耗降低65.8%。

硫酸盐还原菌对UASB中VFA的转化的促进研究

厌氧反应器运行过程中,由于产甲烷菌不能及时转化由产酸菌生成的挥发性脂肪酸,容易造成酸的积累产生的酸败问题。实验通过人工模拟挥发性脂肪酸(VFA)积累,添加适量硫酸盐的方法,研究硫酸盐还原菌(SRB)对于挥发性脂肪酸转化的促进作用。结果表明,当UASB容积负荷从8 kg/(m3·d)提升至15 kg/(m3·d)时,反应器会出现酸败现象。当COD/ρ(SO42-)为30时,UASB受酸败的影响最小。COD去除率稳定在70%以上,pH为6.0,VFA浓度为22.65 mmol/L。向某酸性豆制品废水中以COD/ρ(SO42-)=30投加硫酸盐,能快速降低VFA浓度,使反应器快速恢复。

UASB反应器处理城市生活污水的试验研究

利用成功启动的上流式厌氧污泥床(UASB)反应器形成的颗粒污泥提高对低浓度有机污水的处理效果。结果表明,在COD为300 mg/L的低浓度下,在温度为35℃时,历经90 d成功启动UASB反应器,在UASB内形成黑色颗粒污泥;当HRT为4 h时,其对COD的去除率超过80%。最终UASB反应器中有73.64%的污泥粒径>0.25 mm。UASB运行稳定后,当HRT为3 h,温度为16～21.1℃时,污泥能膨胀至整个反应区,此时COD去除率为86.35%～94.60%,平均COD去除率为91.05%,出水COD≤43 mg/L。

UASB+CASS组合工艺处理啤酒生产废水

采用UASB+CASS组合工艺处理啤酒废水,介绍了工艺选择的依据、工艺流程、工艺参数、运行效果及技术经济指标。工程运行结果表明:该工艺处理效率高,最终出水COD Cr、BOD 5、SS、NH 3-N、TP质量浓度分别为35、15、32、3.56、0.18 mg·L^-1,达到GB 19821-2005《啤酒工业污染物排放标准》表1中标准要求。

UASB+两级AO+化学除磷+稳定塘+人工湿地组合工艺处理奶牛养殖废水

广东某奶牛养殖场采用UASB+两级AO+化学除磷+稳定塘+人工湿地组合工艺处理养殖废水,出水水质COD≤70 mg/L,BOD_5≤20 mg/L,SS≤60 mg/L,NH_3-N≤10.0 mg/L,TP≤7.0 mg/L,粪大肠菌群数≤3 000个/L,各项指标均能达到广东省《水污染排放限值》(DB 44/26—2001)中第二时段一级标准污染物排放限值的要求。该工艺运行稳定,耐冲击负荷强,高效,环境、社会效益显著。