磷元素在饮用水生物处理中的限制因子作用

应用细菌生长潜力(BGP)法,考察了磷元素在淮河流域某地面水厂饮用水生物处理工艺中的限制因子作用原水添加50μg·L^-1KH₂PO₄-P后,BGP可以提高54%,添加其它无机元素和添加磷元素对BGP的影响没有显著差异;原水添加20mg·L^-1C₆H₁₂O₆对BGP的影响要小于添加50μg·L^-1KH₂PO₄-P的影响;原水添加磷后生物滤池对COD_Mn的去除率比对照生物滤池提高了7.5%,其出水明显表现为碳限制型,对照生物滤池出水则为磷限制型.结果说明磷元素是该水厂饮用水生物处理的限制因子,且限制作用强于碳元素,可以通过外加磷源的方法提高饮用水生物处理工艺对有机物的去除效率.     

Continuous biohydrogen production from diluted molasses in an anaerobic contact reactor

An anaerobic contact reactor (ACR) system comprising a continuous flow stirred tank reactor (CSTR) with settler to decouple the hydraulic retention time (HRT) from solids retention time (SRT) was developed for fermentative hydrogen production from diluted molasses by mixed microbial cultures. The ACR was operated at various volumetric loading rates (VLRs) of 20–44 kgCOD·m^-3·d^-1 with constant HRT of 6 h under mesophilic conditions of 35°C. The SRT was maintained at about 46–50 h in the system. At the initial VLR of 20 kgCOD·m^-3·d^-1, the hydrogen production rate dropped from 22.6 to 1.58 L·d^-1 as the hydrogen was consumed by the hydrogentrophic methanogen. After increasing the VLR to 28 kgCOD·m^-3·d^-1 and discharging the sludge for 6 consecutive times, the hydrogentrophic methanogens were eliminated, and the hydrogen content reached 36.4%. As the VLR was increased to 44 kgCOD·m^-3·d^-1, the hydrogen production rate and hydrogen yield increased to 42.1 L·d^-1 and 1.40 mol H₂·molglucose-consumed^-1, respectively. The results showed that a stable ethanol-type fermentation that favored hydrogen production in the reactor was thus established with the sludge loading rate (SLR) of 2.0–2.5 kgCOD·kgMLVSS^-1·d^-1. It was found that the ethanol increased more than other liquid fermentation products, and the ethanol/acetic acid (mol/mol) ratio increased from 1.27 to 2.45 when the VLR increased from 28 to 44 kgCOD·m^-3·d^-1, whereas the hydrogen composition decreased from 40.4% to 36.4%. The results suggested that the anaerobic contact reactor was a promising bioprocess for fermentative hydrogen production.     

Nitrifying population dynamics in a redox stratified membrane biofilm reactor (RSMBR) for treating ammonium-rich wastewater

Nitrogen removal performance and nitrifying population dynamics were investigated in a redox stratified membrane biofilm reactor (RSMBR) under oxygen limited condition to treat ammonium-rich wastewater. When the NH4+-N loading rate increased from 11.1±1.0 to 37.2±3.2 gNH4+-N·m-2·d-1, the nitrogen removal in the RSMBR system increased from 18.0±9.6 mgN·d^-1 to 128.9±61.7 mgN·d^-1. Shortcut nitrogen removal was achieved with nitrite accumulation of about 22.3±5.3 mgNO2--N·L-1. Confocal micrographs showed the stratified distributions of nitrifiers and denitrifiers in the membrane aerated biofilms (MABs) at day 120, i.e., ammonia and nitrite oxidizing bacteria (AOB and NOB) were dominant in the region adjacent to the membrane, while heterotrophic bacteria propagated at the top of the biofilm. Real-time qPCR results showed that the abundance of amoA gene was two orders of magnitude higher than the abundance of nxrA gene in the MABs. However, the nxrA gene was always detected during the operation time, which indicates the difficulty of complete washout of NOB in MABs. The growth of heterotrophic bacteria compromised the dominance of nitrifiers in biofilm communities, but it enhanced the denitrification performance of the RSMBR system. Applying a high ammonia loading together with oxygen limitation was found to be an effective way to start nitrite accumulation in MABs, but other approaches were needed to sustain or improve the extent of nitritation in nitrogen conversion in MABs.     

三维电极电催化氧化法处理废水的研究进展

综述了近几年国内外在三维电极电化学反应器方面的最新研究进展,分析了电源的输出形式、阴阳极板的布置方式、粒子电极的填充方式等因素对废水处理效果的影响,探讨了碳纳米材料等新材料在粒子电极载体上的应用,最后介绍了三维电极法与其他技术联用的最新研究,并指出了三维电极法存在的问题及今后的研究方向。     

陶瓷纤维滤管在烟气净化一体化技术中的应用

在对国内外现有的一体化烟气处理工艺系统梳理的基础上,重点分析了基于陶瓷纤维滤管的烟气净化一体化技术,对其技术原理、应用特性、应用现状进行了分析总结,并以江苏某垃圾焚烧发电厂中试示范项目为例进行验证.结果表明,NOx、SO2、HCl、颗粒物、二噁英类去除效率分别为97.6％、84.1％、74.8％、>99.9％、99.9...     

改进型ABR+复合生物反应器处理糕点残渣废水

介绍了改进型ABR+复合生物反应器在糕点残渣废水处理工程实例中的应用,运行结果表明:该工艺运行稳定、操作简便、运行成本低,处理糕点残渣废水可获得良好的效果,出水水质达GB 8978—1996《污水综合排放标准》中的一级排放标准。     

Fermentative hydrogen production from beet sugar factory wastewater treatment in a continuous stirred tank reactor using anaerobic mixed consortia

A low pH, ethanol-type fermentation process was evaluated for wastewater treatment and bio-hydrogen production from acidic beet sugar factory wastewater in a continuous stirred tank reactor (CSTR) with an effective volume of 9.6 L by anaerobic mixed cultures in this present study. After inoculating with aerobic activated sludge and operating at organic loading rate (OLR) of 12 kgCOD?m^-3·d^-1, HRT of 8h, and temperature of 35°C for 28 days, the CSTR achieved stable ethanol-type fermentation. When OLR was further increased to 18 kgCOD?m^-3·d^-1 on the 53rd day, ethanol-type fermentation dominant microflora was enhanced. The liquid fermentation products, including volatile fatty acids (VFAs) and ethanol, stabilized at 1493 mg·L^-1 in the bioreactor. Effluent pH, oxidation-reduction potential (ORP), and alkalinity ranged at 4.1–4.5, -250–(-290) mV, and 230–260 mgCaCO₃?L^-1. The specific hydrogen production rate of anaerobic activated sludge was 0.1 L?gMLVSS^-1·d^-1 and the COD removal efficiency was 45%. The experimental results showed that the CSTR system had good operation stability and microbial activity, which led to high substrate conversion rate and hydrogen production ability.     

气浮-复合好氧反应器-BAF处理屠宰废水

活禽屠宰及禽肉加工生产废水有机物和悬浮颗粒物含量较高,可生化性较好。采用气浮-复合好氧反应器-BAF组合工艺处理该废水,运行结果表明:该工艺处理效果稳定,出水水质中COD、BOD5、SS、动植物油、NH3-N的平均浓度分别为50,11,30,10和2 mg/L,水质达到GB 13457—1992《肉类加工工业水污染物排放标准》(禽类屠宰加工)中的一级排放标准。     

球形陶粒滤池对城市尾水净化效果研究

为明确以陶粒为填料生物滤池对尾水中主要营养物处理效果,选择球形陶粒滤池对城市尾水进行净化效果研究。试验在室温条件下采用水力停留时间约2 h,曝气量为0.4 L.min-1的陶粒曝气生物滤池装置对洛阳市某污水处理厂的尾水进行深度处理。研究结果表明：球形陶粒生物滤池对尾水中NH3-N去除效果良好,去除率达76%以上;同时该装置对TN,TP和COD具有同时去除作用。进一步研究陶粒对NH3-N吸附去除特征表明,其等温线吸附符合Freundlich Model,表明陶粒对NH3-N的吸附为多层吸附,且对NH3-N的吸附在5 h基本达到饱和吸附。     

单级好氧生物除磷工艺处理生活污水

采用SBR单级好氧生物除磷工艺处理生活污水,检验该工艺处理实际污水的可行性和稳定性,并与传统厌氧/好氧工艺进行比较.结果表明,当进水磷浓度为2~10mg/L时,SBR单级好氧生物除磷工艺能高效去除污水中的磷,经过长期运行去除效果稳定,去除率保持在90%以上,最高可达98.6%.该工艺对污水中的氨氮、TN、COD等污染物也具有良好的去除效果,平均去除率分别在92%、87%、90%以上,并可实现同步脱氮除磷.SBR单级好氧生物除磷工艺无厌氧段实现强化生物除磷,与传统厌氧/好氧工艺相比,除磷能力相当,但运行成本较低,经济性优势明显.