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191.
192.
采用UASB-SBR-絮凝工艺处理地沟油制生物柴油废水,考察了各个阶段的废水处理效果。实验结果表明:UASB稳定运行阶段进水COD约为15000mg/L时,COD去除率约为87%,出水COD在2500mg/L以下,出水挥发性脂肪酸(VFA)浓度为4~6mmol/L,最佳容积负荷为15.0kg/(m3·d);采用SBR处理UASB出水,当容积负荷为1.5kg/(m3·d)时,出水COD在200mg/L以下,COD去除率在83%以上,ρ(NH3-N)在5mg/L以下,TP约为25mg/L。向SBR出水中加入质量分数为5%的聚合氯化铝进行化学除磷,加入量为5mL/L,处理后废水TP为4~6mg/L。处理后废水的COD,ρ(NH3-N),TP均达到CJ343-2010《污水排入城市下水道水质标准》的A类要求。 相似文献
193.
设计了一种循环式超声强化光催化反应器,以TiO2作为光催化剂,研究了超声功率、TiO2加入量、循环液流速和空气流量对双酚A(BPA)降解效果的影响。实验结果表明:超声与光催化过程在循环式超声强化光催化反应器中实现了较好的协同效应;在初始BPA质量浓度为20.0mg/L、超声功率为600W、TiO2加入量为7g/L、循环液流速为4.05×10-2m/s、空气流量为200mL/min的条件下,反应150min后,BPA降解率可达90.5%,溶液中剩余BPA质量浓度仅为1.8mg/L,反应240min后TOC去除率可达84.5%。 相似文献
194.
诺氟沙星作为一种抗生素广泛应用于人类日常生活,并大量进入水体环境,给水环境质量和生态系统安全带来隐患。研究了由3种不同填料组成的水平流和复合垂直流生物活性滤床对诺氟沙星的去除效果,结果表明,在水力负荷为0.1m^3/(m^2·d)、进水诺氟沙星浓度为392.11—686.17μg/L(平均浓度为500.97μg/L)条件下,复合垂直流滤床对诺氟沙星去除效果普遍好于水平潜流滤床,以沸石为填料的复合垂直流生物活性滤床对诺氟沙星的去除效果最好,平均去除率为80.61%,说明选择合适填料和合适类型的生物活性滤床可以作为去除诺氟沙星的一种有效方法。 相似文献
195.
196.
Wastewater management in small and medium-sized enterprises representing the chemical and food industries was investigated.
The results showed that wastewater discharged from an ink-production factory was highly contaminated with organic pollutants.
Anaerobic biological treatment followed by chemical coagulation using ferric chloride aided with lime proved to be very effective
and produced an effluent that complied with national regulatory standard for wastewater discharge into public sewage network.
Also, management of wastewater from a confectionery factory representing the food sector was carried out. Aerobic biological
treatment using plastic-packed trickling filter proved to be an effective treatment method. However, application of in-plant
control measures alleviated the requirement for the construction of a wastewater treatment plant. The applied pollution prevention
and cleaner production measures involved good housekeeping, recovery of spent chocolate, modification of floor cleaning and
installation of suction devices for the removal of sugar and starch powders. All improvement measures were documented by cost/benefit
analysis. 相似文献
197.
To gain more insight into the interactions between anaerobic bacteria and reactor performances (chemical oxygen demand-COD, 2,4 dichlorophenol-2,4 DCP removals, volatile fatty acid-VFA, and methane gas productions) and how they depended on operational conditions the microbial variations in the anaerobic granular sludge from an upflow anaerobic sludge blanket (UASB) reactor treating 2,4 DCP was studied. The study was composed of two parts. In the first part, the numbers of methanogens and acedogens in the anaerobic granular sludge were counted at different COD removal efficiencies. The relationships between the numbers of methanogens, the methane gas production and VFA production were investigated. The COD removal efficiencies increased to 74% from 30% while the number of total acedogens decreased to 10 from 30 cfu ml(-1). The number of total methanogens and acedogens varied between 11 x 10(3) and 10 x 10(9)MPN g(-1) and 10 and 30 cfu ml(-1) as the 2,4 DCP removal efficiencies were obtained between 60% and 99%, respectively. It was seen that, as the number of total acedogens decreased, the COD removal efficiencies increased. However, the number of total methanogens increased as the COD removal efficiencies increased. Correlations between the bacterial number and with the removal efficiencies obtained in different operational conditions were investigated. From the results presented in this paper a high correlation between the number of bacteria, COD removals, methane gas percentage, 2,4 DCP removals and VFA was observed. In the second part, methanogen bacteria in the anaerobic granular sludge were identified. Microbial observations and biochemical tests were applied to identify the anaerobic microorganisms from the anaerobic granular sludge. In the reactor treating 2,4 DCP, Methanobacterium bryantii, Methanobacterium formicicum, Methanobrevibacter smithii, Methanococcus voltae, Methanosarcina mazei, Methanosarcina acetivorans, Methanogenium bourgense and Methanospirillum hungatei were identified. 相似文献
198.
In Ireland, dairy farmyard washwater commonly comprises farmyard run-off and dairy parlour washings. Land-spreading is the most widely used method for treating this wastewater. However, this method can be labour intensive and can cause, in some cases, the degradation of surface and ground waters, mainly due to nitrogen contamination. In this study, a horizontal flow biofilm reactor (HFBR) with step-feed was constructed and tested in the laboratory, to remove organic carbon and nitrogen from a agricultural strength synthetic washwater (SWW). The HFBR had an average top plan surface area (TPSA) of 0.1002 m(2) and consisted of a stack of 45 polystyrene horizontal sheets--15 sheets embedded with 25 mm deep frustums above 30 sheets with 10 mm deep frustums. The frustums acted as miniature reservoirs. The sheets were alternately offset to allow the wastewater to flow horizontally along each sheet and vertically from sheet to sheet down through the reactor. Biofilms developed on the sheets and treated the wastewater. During the 212-d study, the total hydraulic loading rate based on the TPSA of the sheets was 35 l m(-2) d(-1). SWW was pumped for 10 min each hour, in a step feed arrangement at a rate of 23.33 l m(-2) d(-1) on to the top sheet during Phases 1 and 2, and 11.67 l m(-2) d(-1) onto Sheet 16 during Phase 1 (days 1-92) and onto Sheet 30 during Phase 2 (days 93-212). The substrate loading rate during Phases 1 and 2 was 94.8 g total chemical oxygen demand (COD) m(-2) d(-1) and 10.5 g total nitrogen (TN) m(-2) d(-1), based on the TPSA. At steady state in Phase 2, the unit achieved excellent carbon removal of 99.7% 5-day biochemical oxygen demand (BOD(5)) and 96.7% total COD, equivalent to TPSA removal rates of 67.5 g BOD(5)m(-2)d(-1) and 91.7 g COD m(-2) d(-1). The nitrogen removal percentages were 98.3% total ammonium-nitrogen (NH(4)-N(t)) and 72.8% TN, which equated to TPSA removal rates of 4.8 g NH(4)-N(t) m(-2) d(-1) and 7.6g TN m(-2) d(-1). No sloughing of solids or clogging of media occurred during the study. The unit was simple to construct and operate, with little maintenance. 相似文献
199.
采用气体实验法对PPS滤料在SO2气体中腐蚀失效的过程进行了研究.通过实验前后PPS滤料的机械特性、微观特征和化学结构的分析,认为PPS对SO2气体具有良好的耐腐蚀性.但是,随着SO2气体温度的升高,时间的延长及气体体积比提高,PPS 针刺毡滤料的性能有所下降,尤其是高温能加快腐蚀效果.为了延长使用寿命,应使其工作参数在限定的范围内: 在SO2体积比高于700 mL/m3时,应对烟气进行预处理使其体积比低于实验值,或者使烟气的温度控制在170 ℃以下; 如果烟气中SO2体积比超过预定值,烟气温度又高于170 ℃,则PPS针刺毡滤料连续使用时间应不超过96 h. 相似文献
200.
RP-1400a大气颗粒物(PM10)监测仪的日常维护经验 总被引:1,自引:1,他引:0
RP-1400a大气颗粒物(PM10)监测仪的日常维护和常见故障排除方法的一些经验. 相似文献