污泥生物制酸的影响因素

用城市污水厂污泥作嗜酸菌来源及培养基，通过添加能量物质、提供适当的生长条件，使污泥中的嗜酸菌大量繁殖富集，污泥pH下降，所产酸液可用于沥滤废旧干电池中的重金属。实验结果表明，以FeSO4·7H2O作能量物质时，其最适加入量为6～8g／L；在前5d内污泥pH下降较快，其值低于以单质硫作能量物质的试样，但最终污泥pH很难降至2．0以下；污泥初始pH对污泥酸化速率有一定的影响，即使在污泥pH高达8．0甚至10．0的情况下，嗜酸菌依然能够缓慢生长，逐渐使污泥pH下降；污泥初始pH为4．0时，污泥中嗜酸菌的活性最高，污泥pH下降最快，SO4^2-的产生量最大。     

电厂输煤系统配置静电和布袋除尘设备的比较分析

文章分析了电厂输煤系统产生粉尘污染的原因及其特性,提出了选择配置除尘器的基本原则,是在保证“两头不冒尘”的前提下,做到“室内外达标”。对输煤系统常用的布袋、静电两种除尘配置方式以及设备布置方式进行了比较分析,建议应综合比较系统的初投资、运行费用以及运行率,即系统寿命期成本来选择除尘设备,着重考虑选择长期运行维护工作量低和运行费用低的设备。建议优先采用尘源就地控制以及“干式除尘一于尘回收”的方式,列举了2×300MW机组输煤系统配套布袋除尘器和电除尘器技术参数与经济指标比较表,得出采用静电除尘方式的综合性价比优于布袋除尘方式的结论。     

基于交通流量和路网的区域机动车污染物排放量空间分配方法

针对传统的机动车污染物排放空间分配方法精度不高的问题,提出了一种基于交通流量与道路系统的机动车污染物排放"标准道路长度"空间分配的新方法.该方法以实际道路网络作为机动车污染物排放的分配基底,根据不同等级道路交通流量的差异引入"标准道路长度"转换体系,并利用GIS技术完成机动车污染物排放的空间分配过程.将该方法应用于珠三角地区,建立了2004年珠三角地区的机动车污染物空间分配清单.研究结果表明,珠三角地区机动车高污染物排放集中在车辆保有量大、路网密集、交通流量大的城市和地区,且高污染物排放空问分布情况与主干路网的分布一致,呈现出明显的路状分布;结果显示,该方法能有效降低传统方法空问分配的偏差,尤其当路网分辨率提高时.分配结果精度更高,更切合实际排放情况.     

Distribution of Chironomidae (Insecta: Diptera) in polluted rivers of the Juru River Basin, Penang, Malaysia

The influence of physical and chemical parameters on the abundance and diversity of chironomids was studied in six rivers with moderate to highly polluted water in the Juru River Basin. The rivers: Ceruk Tok Kun (CTKR) as reference site, and polluted rivers of Pasir (PR), Juru (JR), Permatang Rawa (PRR), Ara (AR) and Kilang Ubi (KUR) were sampled over a period of five months (November 2007–March 2008). Nine chirnomid species: Chironimus kiiensis, C. javanus, Polypedilum trigonus, Microchironomus sp., Dicrotendipes sp., Tanytarsus formosanus, Clinotanypus sp., Tanypus punctipennis and Fittkauimyia sp. were identified. Assessment of their relationships with several environmental parameters was performed using the canonical correspondence analysis (CCA). Tanytarsus formosanus was the most dominant in the relatively clean CTKR and moderately polluted JR with mean densities of 19.66 and 25.32 m?2, respectively while C. kiiensis was abundant in more polluted rivers. Tanytarsus formosanus, Dicrotendipes sp. and Microchironomus sp. were grouped under moderate to high water temperature, total organic matter (TOM), total suspended solids (TSS), velocity, pH, phosphates and sulphates. However, Tanypus punctipennis, Fittkauimyia sp., and Clinotanypus sp. were associated with high contents of river sediment such as TOM, Zn and Mn and water ammonium-N and nitrate-N and they were associated with higher dissolved oxygen (DO) content in the water. Chironomus kiiensis, C. javanus and P. trigonus showed positive relationships with TOM, ammonium-N and nitrate-N as well as trace metals of Zn, Cu and Mn. These three species could be considered as tolerant species since they have the ability to survive in extreme environmental conditions with low DO and high concentrations of pollutants. Based on the water parameter scores in all rivers, the highest diversity of chironomid larvae was reported in CTKR. With higher concentrations of organic and/or inorganic pollutants as reported in PPR, KUR and AR, the chironomid larval diversity decreased, and the abundance of tolerant species, mainly Chironomus spp., increased.     

Industrial solid waste flow analysis of eco-industrial parks: implications for sustainable waste management in China

Sustainable waste management in the industrial ecology perspective brings enormous challenges to the existing methodology of waste analysis at the industrial park (IP) scale. In this study, a four-step method was proposed for industrial solid waste (ISW) flow analysis of eco-industrial parks (EIPs) and applied to two IPs in eastern China. According to a park-wide census of 619 industrial enterprises and 105 questionnaires by a survey from 2006 to 2008, the results indicated that: 1) at the enterprise scale, more than 60% of enterprises were small-ISW-generation enterprises which encountered great difficulties on effective waste management; 2) at the IP scale, though the two IPs have set up their own environmental management systems and passed the ISO 14001 certification, the efficiencies of the ISW management systems have yet to be improved in the industrial ecology perspective; and 3) at the regional scale, more than 97% of ISW flowed within the provincial region, indicating that the provincial governments prevented the wastes from flowing into their own “back yard”. Effective waste management should be placed in a broader perspective. Approaches to sustainable waste management may include wastes exchange, efficient waste and information flow, virtual EIP, waste minimization clubs and regionalization of waste management.     

Effects of herbicides on Odonata communities in a rice agroecosystem

The effects of the five herbicides propanil, quinclorac, molinate/propanil, 2,4-D amine, and bensulfuron on Odonata diversity and abundance at the experimental rice plots was investigated. A total of 13 Odonata morphospecies belonging to two families have been identified. Treated plots exhibited higher species richness (up to 12 species) than the control plot (8 species). Ishnura spp. was the most abundant species in the treated plots with a mean density of 194.2 individuals per m², (ind m^?2) followed by Brachythemis contaminata (152 ind m^?2) and Agriocnemis spp. (124 ind m^?2). In the control plots, Agrocnemis spp. was the dominant species (153 ind m^?2) followed by Ishnura spp. (143 ind m^?2) and Neurothemis fluctuans (59 ind m^?2). In the propanil-treated plot, the highest number of odonate species (10 species) was recorded followed by the plots treated with quinclorax and molinate/propanil (9 species). On the 2,4-D amine or bensulfuron-treated plots as well as the control plot, only eight odonate species were recorded. This study revealed that herbicide application had a positive effect on Odonata diversity. This seems reasonable as Odonata are non-target organisms for herbicides. Furthermore, the decomposed weeds resulting from herbicide application would enrich the water with necessary organic matter.     

Isolation and identification of a bioflocculant-producing strain and optimisation of cultural conditions via a response surface model

A bioflocculant-producing strain named MY6-2 was isolated from a mixed activated sludge by a nitrogen-free medium. Based on 16S rDNA sequence, biochemical and morphological characteristics, the strain MY6-2 was identified as Bacillus mucilaginosus. The chemical analysis indicated that the flocculant MY6-2 was mainly composed of extracellular polysaccharide. The result of the composition of the medium showed that MY6-2 was able to generate bioflocculant in a nutrient-poor medium that consisted of 5?g?L^?1 sucrose and no nitrogen source. Response surface methodology (RSM) was used to optimise the fermentation condition of MY6-2 for maximum flocculating activity by using central composite design (CCD). Based on the result, the optimum conditions were as follows: 100?mL of broth in a 250?mL Erlenmeyer flask, initial pH 8.0 and inoculum concentration 10%, respectively. The highest flocculating rate of 90% was achieved under these conditions by adding 0.5?mL fermentation supernatant to 95?mL of Kaolin suspension.     

生产性噪声的危害与控制措施

中煤龙化化工公司是一个大型的煤化工企业,高温、高压、易燃、易爆、有腐蚀性特点的企业必然伴有高噪音危害因素,氧压机、汽轮机、破碎机、泵、排气放空等噪声无处不在。     

黄浦江上游来水与黄浦江水源水质内在关联研究

使用有机污染综合指数评价和数理统计方法,对1986—2000年黄浦江水源地及黄浦江上游来水的水质监测数据进行分析。结果表明,黄浦江水源近15a水质变化可分为缓慢恶化、加速恶化和逐渐改善3个阶段;黄浦江松浦大桥取水口水质与园泄泾相近,且均劣于淀峰和太浦河,优于大泖港;大泖港与松浦大桥水质密切相关,对松浦大桥取水口水质恶化贡献很大。基于这一机理建立的回归方程能够较好地拟合出取水口水质的演变趋势。     

Improvements in the stability of biodiesel fuels: recent progress and challenges

Environmental Science and Pollution Research - Fewer fossil fuel deposits, price volatility, and environmental concerns have intensified biofuel-based studies. Saccharification, gasification, and...