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关键词： Membrane bioreactors   Membrane fouling   Biocake dynamics   Morphology characterization   Microbial community  

摘要： Biocake governs membrane fouling in anaerobic membrane bioreactors (AnMBRs) and thorough understandings of its dynamics could aid in better fouling control. However, little is known about biocake dynamics in the AnMBRs, especially compared with the well-studied aerobic membrane bioreactors (AeMBRs). Hence, a comprehensive investigation on biocake dynamics of an AnMBR was conducted, simultaneously operating an AeMBR with identical conditions for comparisons. Observed by the scanning electron microscopy (SEM) and confocal laser scanning microscope (CLSM) in 3D-mode, the biocakes of the AnMBR possessed smoother morphology and denser structure than those of the AeMBR regardless of fouling stages. Fluorescence staining of extracellular polymeric substances (EPS) matrix of biocakes integrated with quantitative and chemical analyses illustrated that the dynamics of the biocake components in the AnMBR featured as a steady and progressive process but drastic in the AeMBR. The sequencing data similar to the SEM and CLSM observations showed that filamentous bacteria (i.e., the f_Anaerolineaceae) dominated in the AnMBR biocakes. In the AeMBR, the f_Microscillaceae prevailed in the biocakes and increased markedly from 24.38% to 36.67% after TMP jump. According to network analysis, microbial interactions were more positive but less intensive in the AnMBR compared with the AeMBR, which might mutually impact with the biocake dynamics. As the keystone taxa, the f_Anaerolineaceae and f_Microscillaceae had strong positive correlations with the variation of organic foulants in the biocakes of AnMBR and AeMBR, respectively, indicating their significant roles in the fouling evolution. Overall, this study provides new insights into the biocake dynamics in AnMBRs and facilitates to gain better understandings of differences in fouling evolutions between AnMBRs and AeMBRs.

关键词： MBR   污水处理   环境工程  

摘要： 膜生物反应器(MBR)是一种较新型的污水处理工艺、相比较于传统的活性污泥法,最早在上世纪90年代由国外引进,现在国内应用逐渐广泛。也取得了一定的成果,本文综合近年来MBR工艺的创新应用,分析目前存在的问题,并总结出未来的研究热点和发展建议。

关键词： 膜生物反应器   高浓度   有机废水   膜污染  

摘要： 随着我国社会经济的逐步发展,工业技术得到全面革新,行业发展速度得到全面提高。但是,在工业发展的背后,工业污染带来的危害不容忽视,而工业废水排放是造成工业污染的重要原因。废水处理可以有效降低工业废水的有害物质含量,减轻水污染。膜生物反应器是当前先进的废水处理工艺,尤其对高浓度废水有较好的处理效果。鉴于此,本文研究了膜生物反应器在高浓度有机废水处理中的应用。

关键词： Spiral symmetric steam anaerobic bioreactor   Anaerobic granular sludge   Soybean product processing wastewater   Operation strategy   Sludge bed characteristics  

摘要： A 300m(3)/d demonstration project of soybean-process wastewater has been established recently with a Spiral Symmetric Stream Anaerobic Bioreactor (SSSAB) as the core. In order to obtain the optimal operation strategy for a full-scale SSSAB and to make it run efficiently and stably in a demonstration project, a Pilot-scale SSSAB (P-SSSAB, effective volume 100 L) was performed for the treatment of soybeanprocess wastewater over 216 days. The volumetric load rate (VLR) range of the P-SSSAB was 0.32 similar to 27.17 kg COD/(m(3).d), where the highest VLR [27.17 kg COD/(m(3).d)] was 2.01 times to the highest value [13.5 kg COD/(m(3).d)] reported. The pH and VFA/ALK of the effluent from the P-SSSAB were in the range of 6.9 up to 9.2 and 0.03 up to 0.17, respectively. The methane yield of the P-SSSAB increased from 0.03 m(3) /kg COD to 0.47 m(3)/kg COD, which was 3.36 times to the maximum value (0.14 m(3) /kg COD) reported. To meet the influent requirement of the aerobic biological treatment in demonstration project (influent COD <= 1.5 g/L), the maximum VLR of SSSAB was optimal at about 22 kg COD/(m(3).d). By analyzing the sludge bed characteristics of the P-SSSAB, it was obvious that zone I (the bottom of the bed) was the major contributor of the COD removal, while zone III (the upper part of the bed) was the major contributor for the NH4+-N increase. The anaerobic granular sludge (AGS) in the bed showed a good granulation. The average MLVSS/MLSS value in sludge bed was about 0.7, and PN/PS in TB-EPS (zone I, II and III) increased to 6.830, 4.257, and 3.747, respectively. SMA and coenzyme F 420 values of zone III were the maximum [666.35 ml CH4/(g VSS.d) and 0.690 mol/g VSS, respectively]. According to the analysis obtained from the 16S rRNA high-throughput sequencing, the microbial community in the AGS had been more specific to the soybean-process wastewater since the bacteria Firmicutes were increased. The relative abundance of microbe which perform direct interspecies

关键词： 膜生物反应器   MBR   污水处理  

摘要： 膜生物反应对有机废水具有强大的处理能力,可实现水循环使用,从而解决我国水资源匮乏问题。文章综述了膜生物反应器应用现状和发展趋势,介绍了常见的膜生物反应器应用实际案例,探讨了膜生物反应器未来的研究及发展方向。

关键词： 体外培养红细胞:路径   造血干细胞   生物反应器   输血  

摘要： 红细胞(RBCs)是临床输血治疗中需求最大的血液制品之一,目前主要依靠献血者提供,供需矛盾极其突出。体外培养的可定制RBCs为解决这一矛盾带来了曙光。RBCs可以从人类诱导的多能干细胞(IPSCs)、永生化成体红系祖细胞、胚胎干细胞(ESCs)、脐带血(UCB)和外周血(PB)中提取的造血干细胞或单个核细胞等途径分化培养获得。这些路径各有利弊也都尚处于实验室研究阶段,但从目前的进展来看,进入临床应用已为时不远。我们拟对此方面的进展进行综述。

关键词： Oxygen transfer   Supersaturated dissolved oxygen   High mixed liquor suspended solids   Biological wastewater treatment   High-loaded membrane bioreactor  

摘要： Conventional diffused aeration systems (such as fine-bubble diffusers) exhibit a poor oxygen transfer in wastewater treatment plants (WWTPs), particularly when operating at sludge concentrations higher than 15 g L-1. The supersaturated dissolved oxygen (SDOX) system has been proposed as an alternative for supplying dissolved oxygen (DO) at high mixed liquor suspended solids (MLSS) concentrations. The advantages introduced by such technology include the possibility of operating WWTPs at much higher than usual MLSS concentrations, increasing the treatment capacity of WWTPs. Recent studies have demonstrated that the SDOX system has higher oxygen transfer rates (OTRs) and oxygen transfer efficiencies (OTEs) relative to fine-bubble diffusers. However, it is unknown lithe high-pressure conditions introduced by SDOX may possibly impact the biological performance of WWTPs. In this study, the effects of SDOX technology on the biological performance of a membrane bioreactor (MBR) were evaluated. The MBR was operated at an MLSS concentration of approximately 15g L-1 in four phases as follows: (P1) with bubble diffusers, (P2) with an SDOX unit, (P3) with the bubble diffusers, and (P4) with the SDOX unit. The performance of the MBR was assessed by monitoring the sludge concentration, as well as changes in the particle size distribution (PSD), sludge activity, organic matter removal and nitrification performance, and changes in the microbial community within the MBR. The operational conditions exerted by the SDOX technology did not affect the concentration of active biomass during the study period. The biological performance of the MBR was not affected by the introduction of the SDOX technology. Finally, the microbial community was relatively stable although some variations at the family and genus level were evident during each of the study phases. Therefore, the SDOX system can be proposed as an alternative technology for DO supply in WWTPs increasing the overall treatment capac

关键词： 污水处理厂   COD   化工园区   MP-MBR  

摘要： 山东某园区污水处理厂主要接收园区制药、化工等企业废水,设计进水标准综合考虑类似工业园区污水水质及《污水排入城镇下水道水质标准》(CJ343-2010),设计出水标准为国标一级A,处理工艺采用“水解酸化+A2O+MBR”的多相组合膜生物反应器技术(MP-MBR),注重废水的预处理技术、厌氧处理技术、好氧处理技术与膜技术的有机组合。自2019年至2020年7月,进水COD、BOD5、氨氮、TN、TP平均值为:70.42mg/L、26mg/L、8.74mg/L、13.67mg/L、0.62 mg/L,出水COD、BOD5、氨氮、TN、TP平均值为29.81mg/L、5.6mg/L、0.72mg/L、0.21 mg/L 。处理系统对COD、BOD5、氨氮、TN、TP的去除率分别为57.67%、78.46%、91.76%、45.50%、66.13%。运行分析表明,虽然污水厂进水指标都较低,但水质水量波动较大,COD主要为难生物降解有机物,生化效果较差,传统工艺结合膜分离技术,提高了整个系统的抗冲击负荷能力,并且,MBR膜能够很好的截留绝大部分不溶性难生物降解有机物,对该污水厂COD的稳定达标起到了关键保障作用。

关键词： 计算流体力学   组织工程   组织再生   生物反应器   应用进展  

摘要： 目的综述计算流体力学(computational fluid dynamics,CFD)在组织工程中的应用进展。方法广泛查阅CFD应用于组织工程的相关文献,主要对CFD用于生物反应器设计改良或优化、模拟体外组织再生过程中的流体动力学和细胞生长动力学等方面进行综述。结果 CFD的模拟预测能力可为生物反应器的设计优化和体外组织工程组织培养提供重要的指导作用,且结合实验研究能进一步提高模型预测结果的准确性。结论 CFD作为新兴和有效的研究工具,已在组织工程中展现出独特优势并取得显著进展,但更全面、准确地模拟组织再生全过程仍需进一步研究。

关键词： 硝酸盐驱动反硝化   烟气脱汞   微生物  

摘要： 作者构建了硝酸盐驱动的反硝化膜生物反应器,膜生物反应器能够有效烟气脱汞,汞的去除效率可达88.72%。通过反应器生物膜SEM-EDS、XPS、HPLC表征分析,SEM-EDS发现菌体表面对Hg成功进行了吸附;XPS分析表明与Hg^(0)接触后微生物产生HgCl_(2)特征峰;HPLC分析发现Hg^(0)转化为Hg^(2+)与MeHg。采用16S rDNA研究膜生物反应器微生物群落结构,结果表明,随着长时间运行,汞进气负荷导致微生物的群落多样性先降低后升高,40、90与230 d的优势菌属分别为Thauera、Brachymonas、TissierellaSoehngenia;Halomonas、Zobellella、Acholeplasma;Halomonas、Aeromonadaceaebacterium、LNRA2-18、Olivibacter。