气升式反应器内流场动力学特性PIV试验研究

气升式反应器内气液两相流动力学特性对提高传质效率和降低运行成本有重要意义.基于粒子图像测速(PIV)技术,在改变曝气强度的条件下,分析距曝气管不同位置处反应器轴向各区域的液相流场、雷诺应力以及气泡动力学特性.结果表明,曝气强度对液相流场和雷诺应力的影响较大,在一定范围内增加曝气强度可以使得液相速度和雷诺应力值增加.同时分析了4mm孔径下圆帽状气泡的动力学特性.     

Inorganic nitrogen removal of toilet wastewater with an airlift external circulation membrane bioreactor

Removal of inorganic nitrogen (inorganic-N) from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor (AEC-MBR) was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19-0.40 kg inorganic-N/(m3·d) helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen (DO) on inorganic-N removal were examined. Under the condition of MLSS at 1.56-2.35 g/L, BOD5/ammonia nitrogen (NH/-N) at 1.0, pH at 7.0-7.5, and DO at 1.0-2.0 mg/L, the removal efficiencies of NH4 -N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5-1.5 RMB yuan/m3, and the energy consumption was approximately 0.72 kWh/m3 at the flux of 8 L/(m2·h).     

曝气量对SBAR中好氧颗粒污泥特性的影响

采用SBAR反应器对比研究了颗粒化后表观气速为1.8 cm·s-1和0.9cm·s-1时对成熟好氧颗粒污泥形态结构、粒径、强度等物理特性和硝化性能以及胞外聚合物代谢的影响.结果表明,颗粒化后降低曝气量增加颗粒形态不规则程度,空隙增大;55d试验中,与高曝气量下相比,降低曝气量使表观污泥产率提高33%,颗粒粒径平均增长速率提高25%,相对颗粒强度降低6%, EP5含量平均降低12%.两反应器颗粒污泥SVI值均在10～15 mL·g-1,沉降性能良好,且均具有良好硝化性能和降解COD能力.与高曝气量下相比,低曝气量下硝化菌群活性低,而异养菌活性高.     

UBF反应器处理低浓度生活污水的启动研究

文章对上流式厌氧污泥床-厌氧滤池反应器在常温下(25±1℃)处理低浓度生活污水进行了启动试验研究。反应器经过约60d的启动后,在水力停留时间(HTR)为4.17h、进水容积负荷为3.08kgCOD/m·3d时,其COD去除率稳定在90%左右,产气率为0.135m3/m·3d,出水pH值与挥发性脂肪酸(VFA)总量分别在6.65～6.96与8.4～13.3mg/L之间波动,整个系统运行稳定。     

Enhanced struvite recovery from wastewater using a novel cone-inserted fluidized bed reactor

The feasibility of struvite recovery at low （12.5 mg/L） and high （120 mg[L） phosphorus concentrations was studied by constructing a novel fluidized bed reactor with cones （FBRwc） and without cones （FBRwoc）. The crystallization process was continuously operated for 133 days under different hydraulic retention times （HRT = 1-10 hr）, pH （7.5-10）, and molar ratios of Mg/P （0.75-1.75）, N/P （1-10） and Ca/Mg （0-2）. The optimum operating conditions of HRT, pH, Mg/P and N/P molar ratios were found to be 2 hr, 9, 1.25, and 7.5, respectively. Under these optimum conditions, the phosphorus precipitation efficiencies of FBRwc were 93% for low and 98% for high phosphorus influent; however, the efficiencies were 78% and 81% for FBRwoc, respectively. Due to crystal losses at each junction （17%-31%）, the crystal recovery efficiency of FBRwoc was relatively low （47%-65%） for both influent concentrations. However, the losses were minimal in FBRwc, which showed 75% and 92% crystal recovery for low and high phosphorus concentrations, respectively. At low calcium concentration, crystal chemical analysis showed the product to be pure struvite （〉 99%）. The scanning electron microscope and X-ray diffraction results further confirmed that the crystal recovered from FBRwc contained pure struvite, which could be considered a high quality fertilizer. Except HRT, all parameters （pH, Mg/P, N/P and Ca/Mg） were found to be influencing factors for FBRwc performance. Overall, inserting cones in each part of the reactor played a significant role in enhancing struvite recovery from a wide range of phosphorus-containing wastewater.     

放电作用下四氯化碳的吸附、脱附及降解特性

考察了填充式反应器中放电对四氯化碳（CCl₄）的吸附、脱附作用影响．结果表明,放电作用下CCl₄在反应器中的移动速度加快,穿透时间的从17min缩短到6min,脱附时间约从60min缩短至14min,反应器对CCl₄的吸附能力显著下降;脉冲电压峰值越高,CCl₄吸附一脱附速率越快,降解效率越高．载气成分对CCl₄影响,在电压为50kV的条件下,分别以氮气和氧气作载气,CCl₄的降解效率可达69.1％和97.6％;放电可对吸附剂起脱附再生作用,具有放电脱附速率快、工艺简单等特点,有较好的应用前景．     

MBR出水后置化学除磷研究

选用不同的化学除磷药剂及固液分离方式,针对膜生物反应器出水进行后置化学除磷静态试验研究。试验表明,在MBR出水平均浓度为(6.0±0.3)mg/L时,在化学药剂的最佳投药量和混凝时间的条件下,TP可以稳定达到一级A标准,去除率达到95%以上;滤液达一级A标准,氯化铝、氯化铁、聚合硫酸铁、硫酸铝最佳投加量为1.5 mol/mol,硫酸铁、聚合硫酸铝最佳投加量为3.0 mol/mol,最佳混凝时间均为10 min;滤纸和滤膜可以有效分离混凝混合液中的TP,滤液TP可稳定达一级A标准,而微网对混合液中粒径小于D10的颗粒无法分离,致使滤液TP无法达标;PAM投加后,絮体粒径显著增大,固液分离效果也相应增强。微网分离效果较投加前有了明显提高,滤液TP可稳定达到一级B标准。     

一种序批式生物膜反应器及其氧传递系数测定

介绍了一种序批式生物膜反应器 ,并求出了在给定的工艺条件下的氧传递系数。结果表明 :本反应器有较强的氧传递能力 ,能满足微生物的新陈代谢和降解有机污染物的需要     

膜生物反应器处理垃圾渗滤液研究综述

传统生物处理工艺对垃圾渗滤液,特别是老龄化垃圾渗滤液处理效果差,而膜生物反应器(MBR)在这方面显现出巨大优势。MBR通过截留微生物保持高生物量浓度,只需较短的水力停留时间,并可承受较大有机负荷率,能有效去除有机物及微污染物,对氨氮的去除率达90%以上。优化条件下,对老龄垃圾渗滤液中COD的去除率达75%以上。虽然MBR性能稳定,但较短的水力停留时间和高浓度的氨氮对反应器有不良影响,并且较大的污泥龄也会降低反应器的性能。然而厌氧MBR和改进型活性炭粉末MBR在垃圾渗滤液的治理中表现出了巨大的潜力。     

两相一体式污泥浓缩消化(TISTD)反应器微生物多样性研究

针对课题组开发的两相一体式污泥浓缩消化反应器(TISTD),采用16S rDNA、PCR-TGGE等分子生物学技术,对反应器在不同阶段稳态下的内、外反应室中微生物的多样性和种群结构进行了研究.结果表明:TISTD反应器内外反应室中微生物群落均呈现高度的多样性分布,优势菌群明显,群落结构差异性很大,且外反应室较内反应室具有更多的微生物种群数量,外室是水解酸化的场所,污泥在外室经过微生物的水解酸化后进入内室,内室是严格厌氧的产甲烷场所;从反应器运行的不同时期来看,反应器中微生物优势种群呈现一定的差异,随着反应器负荷的改变,微生物的群落结构和种群数量也呈现出明显的演替过程,优势种群的功能地位处在动态变化中.微生物种群之间通过协同和竞争作用,形成了特定生态位的群落结构.研究结果解释了TISTD反应器同时浓缩和消化的工作机理,并为其推广、应用及优化调控提供了理论基础.