混凝好氧颗粒污泥的絮凝剂选择

为选择出适应于混凝好氧颗粒污泥培养的絮凝剂,通过絮凝剂添加量、污泥浓度、搅拌速度、搅拌时间等因子进行L9(3)4正交实验,以COD、浊度去除效果及絮凝颗粒结构为考察因子,研究聚合氯化铝(PAC)、聚丙烯酰胺(PAM)及壳聚糖的絮凝效果。结果表明,在不同絮凝剂的最佳混凝条件下,PAM的效果最好,壳聚糖次之,PAC最差,但壳聚糖COD随其添加浓度的增加而增加;絮凝颗粒结构中,以PAM的絮凝颗粒效果最好,其结构紧溱而颗粒中间的空隙相对较大,有利于吸附污染物和微生物的生长,适宜作为颗粒污泥培养的絮凝剂。     

电镀企业周边大气颗粒物PM_(2.5)、PM_(10)和TSP中重金属分布特征及健康风险评价

以东莞市5个镇区为研究对象,采集电镀企业周边大气样品,分析了样品中重金属(包括As、Co、Cd、Cr、Cu、Mn、Ni、Pb、Sb、V、Zn和Hg)的含量分布,使用富集因子(enrich factor)、地累积指数(index of geoaccumulation)、Hakanson法和美国国家环境保护局(US EPA)的人体暴露健康风险评价模型,对PM_(2.5)、PM_(10)、总悬浮颗粒物(TSP)中重金属进行人体健康风险评价。结果表明,PM_(2.5)、PM_(10)和TSP中As、Cd和Cr平均浓度皆超标。Cr、Ni和V元素在3种颗粒物中非富集,主要为自然源;As、Co、Cu、Pb和Zn,可能来源于自然源和叠加的工业污染。Cd、Hg和Sb浓度受人为污染影响严重。Cd、Sb、Cu、Zn、Pb为生物可利用元素(K>0.6),在环境中的可迁移性高且易于被生物体和人体吸收。Mn元素的非致癌风险值较其他重金属要高1~4个数量级,且儿童的非致癌暴露风险值HQ均高于成人的。3种颗粒物中重金属元素通过呼吸吸入途径产生的非致癌风险HI值均高于人体可接受的上限1.0,其主要贡献来源于Mn的影响,研究区非致癌风险较为严重。除PM_(10)中Co元素和TSP中Co、Cr的成人致癌风险CR值大于10-4之外,其余大部分重金属元素通过呼吸途径产生的致癌风险CR值均在可接受范围之内,此外,3种颗粒物中的成人的致癌暴露风险值CRT均高于儿童的CRT值,并且除了PM_(2.5)中儿童的重金属致癌暴露风险CRT值(4.70E-05)低于人体可接受范围的上限(10-4),其余CRT值均高于10-4,致癌风险较为严重。     

Heavy metal contents and magnetic susceptibility of soils along an urban–rural gradient in rapidly growing city of eastern China

The accumulation of heavy metals (Cd, Cr, Cu, Pb and Zn) and magnetic minerals in soils along an urban-rural gradient in the rapidly growing Hangzhou City, Eastern China, was measured. The analytical results indicated that heavy metal concentrations, magnetic susceptibility (chilf) and saturation isothermal remnant magnetization (SIRM) in soils decreased with increasing distance from the urban center. The significant relationships existed between heavy metal concentrations, chilf and SIRM and distance from the urban center. The soils in the urban areas were enriched with Cd, Cu, Pb and Zn. Elevated concentrations of heavy metals (especially Cd and Zn) in urban areas indicated the evidence for the accumulation of heavy metal contaminants from anthropogenic activities. Enhanced heavy metal concentrations and magnetic susceptibility were located in the uppermost soil horizons (0-10 cm), decreasing downwards to background values. The significant positive correlations between the Tomlinson Pollution Load Index (PLI) and magnetic susceptibility and SIRM were observed in polluted soil samples. Strong positive correlation indicated that magnetic screening/monitoring provided a fast and non-destructive tool, which can be effectively used as a proxy to detect environmental pollution in rapidly growing urbanization regions affected by anthropogenic activities.     

Potential risks of copper, zinc, and cadmium pollution due to pig manure application in a soil-rice system under intensive farming: a case study of Nanhu, China

Heavy metal (copper [Cu], zinc [Zn], and cadmium [Cd]) pollution of soils from pig manures in soil-rice ( L.) systems under intensive farming was investigated, taking Nanhu, China, as the case study area. Two hundred pig manures and 154 rice straws, brown rice samples, and corresponding surface soil (0-15 cm) samples were collected in paddy fields from 150 farms in 16 major villages within the study area. The mean Cu and Zn concentrations in pig manures consistently exceeded the related standard. About 44 and 60% of soil samples exceed the Chinese Soil Cu and Cd Environmental Quality Standards, respectively. The concentration of Cu, Zn, and Cd in brown rice did not exceed the Chinese Food Hygiene Standard. There was a significant positive correlation between total Cu and Zn contents in soil and application rate of pig manures. Strong correlation was observed between the extractable Cu, Zn, and Cd in soil and the Cu, Zn, and Cd contents in the brown rice. The spatial distribution maps of Cu and Zn concentrations in brown rice, straw, and extractable soil Cu and Zn concentration also showed similar geographical trends. Further analyses on heavy metals loading flux and accumulation rates from pig manure applied suggested that Cu and Cd contents in soil currently have already exceeded the maximum permissible limit, and Zn, if still at current manure application rates, will reach the ceiling concentration limits in 9 yr. This study assists in understanding the risk of heavy metals accumulating from pig manure applications to agricultural soils.     

建立公众参与环境影响评价制度

环境评价过程中实施公众参与可提高环境评价的有效性，还可使环境影响评价制定的环境保护措施更具合理性、实用性和可操作性，同时，也体现了环境影响评价工作和对有关部门对公众利益和权利的尊重，并在公众参与的活动中提高公众的环境意识。目前，我国环境影响评价工作中公众参与虽然一直在进行研究，并不断实践着，但对于具体操作却没有详细规定，使得公众参与在实践中存在一定的局限性，因此，有效实施公众参与，建立完善的公众参与环境影响评价制度有着极为重要的理论和现实意义。     

东湖新技术开发区环境现状分析及对策研究

武汉东湖新技术开发区是首批国家新技术产业开发区之一，为了促进开发区的环境与经济的协调发展，加强东湖新技术开发区的环境保护，笔者对东湖新技术开发区环境质量现状进行了调查研究，初步摸清了该区域环境质量状况，指出了目前开发区建设中应重视的环境管理问题，并对开发区的环境保护提出了一些建议，该项研究具有明显的社会和环境效益，对改善武汉市是东湖开发区的投资环境，提高人民生活水平和质量，树立城市新形象有着重要的现实意义。     

从水污染源的氨氮平衡研究石化厂氨氮源头控制的措施

通过建立武汉石油化工厂的在正常生产运行条件下的污水场进水氨氮分布平衡，弄清炼油废水氨氮的来源，找出了污水氨氮源头控制的重点是污水汽提装置的脱硫氨净化水和与全厂设备有关的机泵冷却水等，并根据该厂目前的实际情况，分析了氨氮源头控制的对策。     

东莞市某地区地表水中重金属健康风险不确定性评价

为了解东莞市西南地区(麻涌镇、沙田镇、虎门镇和长安镇)地表水中重金属污染现状与健康风险水平,对研究区域内29个地表水样中As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等重金属元素进行测定,并运用不确定性健康风险评价模型对研究区地表水中的重金属进行健康风险评估。结果表明:该研究区域地表水中重金属引起的致癌风险较高,人均年健康风险都在Ⅴ级风险及以上。化学致癌性重金属引起的人均年健康风险中,以Cr最大,As次之,然后是Cd。非化学致癌性重金属引起的人均年健康风险中,Pb的风险最大,Ni次之,风险均远小于化学致癌性重金属引起的人均年健康风险。因此,该研究区域地表水中重金属健康风险管理应以化学致癌风险为主,重金属污染物的优先控制顺序为CrAsCd。     

Fenton试剂石灰法处理苎麻脱胶前段混合废水的试验研究

探讨了Fenton试剂石灰法处理苎麻脱胶前段混合废水工艺。试验表明,当FeSO₄₂O、H₂O₂（30％）、饱和石灰乳的投加量分别为3 g/L、2 mL/L和3 mL/L时,COD的去除率50％以上,色度去除率达到90％以上。更重要的是,处理后出水可部分回用于煮炼生产,从而节约生产用碱量,减少废水排放量, 还可提高废水可生化性,为后续生物处理创造条件。     

Soil acidification induced decline disease of Myrica rubra: aluminum toxicity and bacterial community response analyses

Environmental Science and Pollution Research - The decline disease of Myrica rubra tree is commonly induced by soil acidification, which affects the yield and the quality of fruits. It is...