城市污泥中重金属的去除方法研究进展

城市污泥中的重金属是影响城市污泥无害化和资源化的主要因素,如何有效去除城市污泥中的重金属是当前市政工程和环境工程研究的热点.在此简要介绍了动电技术、生物沥滤、植物提取、化学处理等重金属去除方法,并在分析这些方法特点的基础上,提出了今后研究去除城市污泥中重金属方法的方向.     

开启式负荷开关与保险丝的正确使用

为防止电器设备短路或因负载增加而使线路电流增大,损坏电气设备,必须在电路的适当位置安装保护性电气设施.开启式负荷开关就是一种常见的保护装置,在盐业系统使用尤为广泛.因此正确地选择使用开启式负荷开关与保险丝,是确保电气设备安全使用的关键.     

Pollutant loads of surface runo inWuhan City Zoo, an urban tourist area

The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load （e.g. animal yard〉roof〉woodland〉road）, with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M（V） curve indicate that no first flush effect existed in the surface runoff from pervious areas （e.g. woodland, animal ground yard）, whereas a first flush effect was evident in runoff from impervious surfaces （e.g. animal cement yard, roof, road）.     

小型垃圾转运站渗滤液特性及其对城市水环境的影响

对两个城市的小型垃圾转运站现状进行了分析,并对其渗滤液产生量及渗滤液性质进行了监测。结果表明:小型垃圾转运站转运量小、分布密集;深圳垃圾转运站产生的混合污水并入城市污水管网,常州的小型垃圾转运站,产生的渗滤液及冲洗废水50%直接排入了河道;转运站排放的混合污水,除汞外,其他指标远超GB 8978-1996《污水综合排放标准》及CJ 3082-1999《污水排入城市下水道水质标准》,小型垃圾转运站排放的污染物中,以COD负荷最高,其次是BOD5。大量的有机物排入城市污水厂,对污水厂的正常运行造成冲击,如果直接排入水体,更加速了水体的污染,因此,常州市城市排水系统优化改造及垃圾转运站的截污、治理势在必行。     

Simultaneous removal of hydrogen sulfide and toluene in a bioreactor: Performance and characteristics of microbial community

We investigated the correlation between performance and the bacteria community composition by H2S and toluene co-treatment. Operation of the bioreactor was divided into four stages, in which the inlet concentration of toluene and H2S were gradually increased. In Stage I, toluene was the sole target compound with an average removal e ciency of 86.49%. After adding H2S in Stage II, removal e ciency of toluene decreased immediately and recovered gradually to 85.96%. When the inlet concentration of toluene and H2S was increased in Stage III and Stage IV, respectively, the average removal e ciency for toluene increased continuously from 86.31% to 87.24%. The elimination capacities of toluene increased with increasing inlet loading rates of toluene and H2S. Results of the PCR-DGGE analysis showed a turnover growth and decline of the microbial populations in the bioreactor. In Stage I, the dominant toluene-degrading bacteria mainly contained Pseudomonas sp. strain PS+ and Hydrogenophaga sp. In Stage IV, however, the dominant toluene-degrading bacteria was aciduric bacteria (Clostridium populeti). The dominant microbial community in the bioreactor enhanced the elimination capacity of toluene, and adding H2S changed the environment of microbial growth, thus resulted in an evolution of dominant microorganisms. Analyses of microbial community and their activities provides valuable information to e ciently enhance simultaneous removal of toluene and H2S in the bioreactor.     

常规工艺强化去除给水系统中的卡马西平

卡马西平作为抗癫痫类药物被广泛使用,在环境中频繁被检出,且浓度较高,不易去除,通常作为环境中药品和个人护理品污染状况的指示化合物,由于它的潜在危害,日益成为新兴污染物研究的重点。模拟城市给水厂工艺流程,研究卡马西平在城市给水处理工艺中的迁移转化规律,并对常规工艺进行强化,找出去除卡马西平的最优条件。在预氧化阶段,氧化剂高锰酸钾最佳投加量为1.5 mg/L,预氧化时间为50 min,卡马西平的最高去除率达到19.8%;在混凝阶段,聚合氯化铝最佳投加量为2 mg/L,在弱酸性条件下对卡马西平的去除率最佳,达到28.7%左右;砂滤阶段的最佳条件为滤柱高度800 mm,过滤速度不超过5 m/h,最高去除率达到11.7%。结果表明:通过高锰酸钾的预氧化作用,城市给水厂常规工艺对水源水中卡马西平的去除率得以较大提高,总去除率达到60.2%。     

氮形态对人工湿地氮去除效果的影响

采用水平潜流人工湿地处理TN质量浓度为20～25 mgL,氮形态分别以NH4+-N,NO3--N和有机氮为主的生活污水,分析了氮形态时人工湿地N去除效果的影响.试验结果显示:相应的TN去除率分别为47.2%,71.6%和33.1%.表明人工湿地主要适用于水的深度处理,实现污水中N的无机化特别是将N转化为NO3--N,可显著提高人工湿地的N去除效果.     

粉煤灰对废水中的石油样品的吸附去除

用紫外分光光度法分析经粉煤灰处理后含油废水中的油样含量。考察了pH值,粉煤灰使用量,接触时间,废水中油样的初始浓度,温度等因素对粉煤灰除油率的影响。结果表明：用石油醚溶解的油样紫外光最佳吸收波长为272．5nm;中性条件下,粉煤灰对废水中的油样有较好的去除率;粉煤灰使用量增大、接触时间增加、温度升高有利于粉煤灰对油样的吸附去除;废水中油样含量越高,粉煤灰对其去除率越低。     

日本超级环保船CO2排放量减少69％

日本邮船采用“综合环保技术”,同样运输量下海运的CO2排放相当于陆运的25％,环境负荷较少。目前国际海运年CO2排放量约为8．4亿吨,未来以新兴国家为主,国际海运的运输量将进一步增加,国际海事机构也逐步开始采取CO2减排的强制性措施。在这样的社会需求下,日本邮船率先开展了船舶CO2减排的研究活动,     

利用绿色巴夫藻去除海水养殖水体中N、P的条件优化

为了研究常用饵料微藻绿色巴夫藻对高密度海水养殖水体中N、P的去除能力,探索去除养殖水体中N、P的最优条件,选择起始藻细胞数量、养殖水体稀释率、温度、光照和盐度五种因素开展正交试验.结果表明养殖水体稀释率为50%时,绿色巴夫藻对NH4-N和PO4-P的平均去除率最高,分别为98.7%和85.5%.各种因素影响藻体去除水体...