湿式空气氧化法处理TNT红水的影响因素

使用湿式空气氧化技术与生物技术联合处理TNT精制阶段所产生的红水，研究了湿式空气氧化过程中反应温度、反应时间、初始压强和pH值对流出物的COD值与流出物可生化性的影响规律。研究结果表明，随着反应温度和反应初始压强的升高、反应时间的延长、催化剂投加量的增加和反应pH值的降低，出水COD值均有所下降。在温度为300℃、初始压强为14MPa、反应时间为2h、pH值为5，3、铁盐催化剂添加量为2g的条件下，出水COD值为498mg／L，COD去除率可达到99．27％。在温度为300℃、初始压强为11MPa、反应时间为1h、pH值为3、添加1g铁盐催化剂的条件下：反应流出物的BOD5／COD值为0．301，此时可生化性已经得到很好改善。通过生物方法对反应流出物后续处理发现，湿式空气氧化技术处理TNT红水在反应温度300℃以上，反应流出物均可生物降解。     

微曝气Fenton氧化法处理模拟双酚A废水的效果及其生物验证

研究了微曝气Fenton氧化法关键工艺参数对模拟双酚A（BPA）废水处理效果的影响，并从活性污泥性质和污染物去除率两方面，采用膜生物反应器(membrane bioreactor, MBR)对微曝气Fenton氧化法的处理效果进行了实验验证，为实现BPA废水的生物处理奠定基础。结果表明，初始pH值、反应时间、H₂O₂/COD(质量浓度比)、H₂O₂/Fe²⁺ (摩尔浓度比)、反应温度及曝气量均对预处理效果有较大影响，在最佳条件下，COD去除率可达70%，BOD/COD值则由原废水的0.02提高到0.50以上。MBR处理上述出水的结果表明，经微曝气Fenton氧化处理BPA的废水，可较好地适应后续的生化处理。     

聚苯胺修饰的辣根过氧化物酶电极的研究

采用电化学聚合法制备聚苯胺膜 ,并通过静电吸附固定辣根过氧化物酶 ,形成聚苯胺修饰的辣根过氧化物酶电极 .聚苯胺在电极与酶分子之间传递电荷 ,因此 ,在没有额外的电子媒介体的条件下 ,这种酶电极对H2 O2 的电流响应高达 2 5 μA ,响应时间小于 15s .酶电极与流动注射分析相结合构成实验系统 ,可以测量 0 1mmol·l-1H2 O2 ,表观米氏常数为Km=9 5 1mmol·l-1.     

Abating whey organic load through ethanol and lactic acid production by kefir

Abstract

The extent to which selected ethanol and lactic acid production bioprocesses contribute to whey waste abatement was examined. Alcoholic fermentation of whey was carried out by kefir cells immobilized on grape stalks, delignified cellulosic materials, or brewer's spent grains. Lactic acid fermentation was also performed by free kefir cells with or without addition of brewer's spent grains as promoting material. Since whey fermentation rate is affected by the lactose uptake rate, ¹⁴C-labeled lactose was used to study the fermentation ability of kefir. The highest reductions in biochemical oxygen demand and chemical oxygen demand of whey, about 68% and 52%, respectively, were achieved by lactic acid fermentation in 6 h at 37 °C and pH 5.5, in the presence of 120 g brewer's spent grains. Additionally, at the same conditions, the highest ¹⁴C-labeled lactose uptake rate by kefir and consequently the highest alcoholic fermentation rate were also recorded. However, greater reductions in biochemical oxygen demand and chemical oxygen demand of whey are required prior to final disposal.     

基于T-Hg2+-T结构的Hg2+生物传感器研究进展

Hg²⁺不仅污染环境,还会引发多种疾病,危害人体健康.因此,实现对Hg²⁺的快速灵敏检测十分必要.传统的Hg²⁺检测方法存在一定的局限性,而基于T-Hg²⁺-T结构的汞离子生物传感器具有高特异性、高稳定性的优势,近些年得到广泛研究和应用.本文简要介绍了T-Hg²⁺-T结构的概念和特点,并从荧光型、比色型和电化学型3个方面综述了基于T-Hg²⁺-T结构的汞离子生物传感器的研究进展,对未来的发展前景进行了展望.     

含荧光素酶四膜虫B2086-LUC全细胞生物传感器的构建及其对重金属离子的响应

为了获得可用于快速检测环境中重金属污染的全细胞生物传感器,本研究将含有HA标签的萤火虫荧光素酶(LUC)基因重组到含有四膜虫金属硫蛋白MTT1启动子和微管蛋白终止子序列的载体pBX中,获得重组质粒pBX-LUC,用基因枪粒子轰击法将pBX-LUC转化入四膜虫细胞中,通过同源重组和巴龙霉素抗性筛选, LUC基因整合到四膜虫大核基因组MTT1 位点,获得含有LUC基因的细胞株B2086-LUC. B2086-LUC对重金属镉和汞的响应敏感,可检测的最低浓度为5~10ng/mL;对铜和锌的响应较弱,可检测的最低浓度为0.5~ 1mg/mL.因此,四膜虫B2086-LUC可作为环境中镉和汞污染快速检测的全细胞生物传感器.     

生化需氧量(BOD_5)测定接种菌剂的研究

利用从市政污水中筛选的3株菌株制备成BOD5接种冻干粉剂,用于BOD5接种。实验确定了冻干粉接种菌剂最佳制备条件。以葡萄糖和谷氨酸配制的标准溶液(GGA)和实际废水为实验对象,完成了制得菌剂与传统接种液(土壤浸出液)及国外商业菌种Polyseed的性能对照。用接种菌剂接种测定GGA的测定结果均在180~230 mg/L,满足标准要求,接种菌剂、土壤浸出液和Polyseed的标准偏差分别为3.60、8.34、2.87 mg/L,测定实际废水的标准偏差分别为8.5、33.26、.0 mg/L。     

Application of Defined Co-Immobilized Microbial Consortium as a Ready-to-Use Seed Inoculum in Bod Analysis

A number of microorganisms were isolated from sewage. Biochemical Oxygen Demand (BOD-5 day) analysis was carried out by individual pure cultures. The cultures giving higher or equal BOD values as compared to reference GGA solution were selected for the formulation of a defined mixed microbial consortium. This microbial consortium was co-immobilized on calcium-alginate beads. Four synthetic and six industrial samples were tested for BOD by using immobilized beads as well as sewage as source of seeding materials. BOD values obtained with beads for all the synthetic as well as industrial samples were fairly comparable with those obtained with sewage. Reusability of prepared microbial beads was also checked with different synthetic and industrial samples and was compared with reference GGA solution. The same microbial beads can be reused three times for different BOD-5 day estimations. It is recommended that immobilized microbial beads can be used as a ready-to-use seeding material for BOD analysis.     

Diffusion pollution from livestock and poultry rearing in the Yangtze Delta,China

BACKGROUND: The Yangtze Delta is one of the most developed regions in China and includes Shanghai, eight cities in Jiangsu province and eight cities in Zhejiang province. Meat consumption in this region has increased with economic growth, and most of the consumed meat is produced locally. The water quality of surface waters has deteriorated in recent years. An example was the huge blue-green algae bloom in Tai Lake in late May 2007, which affected millions of people's daily drinking water. However, animal husbandry is considered to be one of the main pollution sources. METHODS: Pollutants (NH3-N, total phosphorus (TP), and total nitrogen (TN)) excreted by livestock and poultry, and the resultant COD (chemical oxygen demand) and BOD (biochemical oxygen demand), were estimated using two different methods based on different data sets. RESULTS: The number of livestock and poultry has remained stable in the Yangtze Delta over the four years from 1999 to 2002, with the average number of pigs, cattle, sheep and poultry being 21.1 M, 0.4 M, 7.7 M and 597.6 M, respectively. Pollutants in livestock and poultry excreta estimated by Method I were: 0.12 Mt NH3-N, 0.11 Mt TP and 0.29 Mt TN, resulting in COD and BOD of 1.34 Mt and 1.30 Mt, respectively, while the estimations based on Method II were: 0.18 Mt NH3-N, 0.15 Mt TP and 0.40 Mt TN, resulting in COD and BOD of 1.95 Mt and 1.80 Mt, respectively. DISCUSSION: Pollutants excreted annually by livestock and poultry in the Yangtze Delta are estimated to be: 0.17 Mt NH3-N, 0.16 Mt TP and 0.42 Mt TN, giving rise to a COD of 1.86 Mt and a BOD of 1.72 Mt. Approximately 25% of this pollution was estimated to enter water bodies, which means that the annual pollutant load is 43,700 t NH3-N, 39,400 tTP, 104,600t TN with a COD of 465,000 tand a BOD of 430,100 t. Pollutants from animal husbandry were similar in magnitude to those from industrial wastewater. Pigs produced the most pollution, followed by poultry, cattle and sheep. The pollution load from animal husbandry in the Yangtze Delta is about twice the average level of the whole of China. CONCLUSIONS: Domestic wastewater was the main pollution source in the Yangtze Delta, followed by pollution from raising livestock and poultry and from industrial wastewater. The pollution load in Shanghai and Jiaxing were the greatest, followed by 7 cities of Jiangsu province (except Suzhou) and other cities of Zhejiang province and Suzhou. Pigs and poultry produced about 90% of the total pollutants from animal husbandry. RECOMMENDATIONS AND PERSPECTIVES: The local governments, especially in Shanghai and Jiaxing, should focus their attention on the pollution produced by livestock and poulrry. Controlling pollution from pigs and poultry will have the greatest impact in this region. Control of pollution will be facilitated by the development of large-scale livestock and poultry farming units and a shift away from small scale husbandry.