Stabilization treatment of contaminated soil: a field-scale application in Shanghai,China

Stabilization is one of the best demonstrated available technologies for treating toxic pollutants in soils and has been used worldwide but is rarely used for treatment of contaminated sites in China despite many bench-scale studies. Here, a field-scale application of stabilization treatment in Shanghai, China was summarized to demonstrate the whole engineering process and the key technical issues regarding stabilization of contaminated soil. A site contaminated with arsenic (As) and polycyclic aromatic hydrocarbons (PAHs), formerly used as a lighting plant in Shanghai, was chosen as the demonstration site. Stabilizing measures were taken to treat the contaminated soil to reuse the site for residential purposes. The whole engineering remediation process consisted of phase I environmental site assessment (ESA) and phase II ESA, quantitative human health risk assessment, remediation alternatives evaluation, bench-scale testing, remedial design, engineering implementation, and post-remediation assessment. A third party conducted evaluation monitoring indicated desirable results were achieved via the stabilization treatment. In addition, some technical obstacles related to soil stabilization treatment were discussed, including soil quality evaluation, stabilization effectiveness validation, and soil reuse assessment.     

排污权的产权性质分析

排污权交易是利用市场机制控制环境污染的有效途径。明确排污权的产权性质无论是对生产者还是对管理者都具有十分重要的意义。本论文将对排污权的产权性质和内涵进行分析。     

不同交联度PP-g-4VP离子交换纤维的制备及对水溶液中铬离子吸附的研究

通过控制交联剂(DVB)及单体(4-VP)浓度等工艺,研制了不同交联度的聚丙烯接枝4乙烯基吡啶离子交换纤维(PP-g-4VP),旨在改善纤维的结构及其再生吸附和重复使用性能。实验结果表明,随着DVB含量增大,纤维的接枝率下降,交联度增加,而吸水率下降。所制的PP-g-4VP和PP-g-4VP-季铵盐纤维对Cr~(6+)静态吸附量大,分别达约6.5mmol/g和4mmol/g。交联度低时,纤维对Cr~(6+)吸附速度越快,穿透点前流出液浓度较低。纤维吸附Cr~(6+)后用1N NH_3·H_2O能完全洗脱,再生吸附性能良好。     

城市公共厕所对环境的卫生学研究

本文介绍了通过现场调查和实验研究,对六个城市的564座公共厕所进行了分析,结果为:水冲式公厕较非水冲式公厕卫生条件好,用卫生学指标评价水冲式公厕也明显好于非水冲式公厕.水冲式公厕臭气氨的浓度最低值0.11mg/m~3,最高值13.72mg/m~3,硫化氢最低值未检出,最高值0.006mg/m~3;蝇平均少于30只,蛆基本无.非水冲式公厕臭气氨的浓度最低值0.3mg/m~3,最高值26.47mg/m~3.硫化氢最低值未检出,最高值0.385mg/m~3;蝇平均多于30只顺每厕蹲位内多于15尾.研究表明公厕恶臭气体、蝇及她对城市环境和生态有明显的污染,应引起重视并加强改造和管理.     

燃煤电厂周边大气重金属污染特征及来源解析

为探究燃煤电厂周边大气环境中重金属的污染特征与来源,对广东某山区燃煤电厂周边地区环境和污染源的重金属进行测定,分析其污染特征,采用因子分析法和Pb同位素示踪法对环境中的重金属进行来源解析。结果表明,研究区域室内积尘中重金属浓度水平明显高于土壤重金属,污染空间分布与当地气象条件相关。环境空气TSP中重金属主要来自2个污染源,Cd、Pb、As主要来自电厂燃煤,Ca、Mn、Al、Mg主要来自土壤扬尘。TSP、降尘、积尘样品所含的Pb均与电厂采集的煤、炉渣、粉煤灰样品所含的Pb具有同源性,与其他污染源同源性不明显,说明研究区域大气中Pb污染主要来自电厂燃烧所排放的烟尘,其他污染源影响不大。     

医院污水处理设备管理

提高废水处理设备运转率,完好率的首先问题是废水处理设备归谁管、怎样管的问题,纳入企业管理的组成部分,明确管理部门,建立以设备选型到报废更新的工作程序,制定管理制度和岗位责任制,分清职责,分工协作,齐抓共管.同时,因为废水处理设备有它的运行、操作、保养、维修规律,正确操作与维修保养才能使设备处于良好的技术状态,同时机械设备在长期运行中,因摩擦、高温、湿气和各种化学效应的作用不可避免地遣成零部件损坏,配合失调,技术状态逐渐恶化,作业效果逐渐下降.多年实践证明作好废水处理管理的五个要点,才能及时、快速、高质量地维修设备以恢复性能,处于良好的工作状态.     

Experimental analysis of the evaporation process for gasoline

This paper presents the findings from a study on the evaporation process of 93 RON (research octane number) unleaded gasoline. The parameters measured in the experiment included the weight, the RVP (Reid vapor pressure) and the viscosity of gasoline, the concentration of NMHC (non-methane total hydrocarbon) in the oil vapor and the concentration of the main vapor constituent. Results showed that the parameters changed significantly as evaporation processed. The weight loss reached 86.36% after 300 days and presented a logarithmic curve with time. The RVP decreased from 38 kPa to 9.6 kPa. The viscosity of gasoline increased from 8.6 × 10^?4 Pa s to 1.51 × 10^?3 Pa s. All the concentrations of NMHC and the main constituent of vapor decreased in varying amounts. Most of the changes might be attributed to the evaporation of volatile hydrocarbons.     

微囊藻毒素产生过程中磷素行为与作用研究

通过培养实验考察了微囊藻生长过程中磷素的吸收利用情况,研究了可溶解性正磷酸盐对产毒微囊藻生长状况及几种不同磷形态在不同浓度下对微囊毒素产率的影响.结果表明,可溶性反应磷浓度的增加可以促进微囊藻生长,磷浓度为0.55mg.L-1更适宜微囊藻生长,不超过0.55 mg.L-1的磷对微囊藻产毒有促进作用,无磷时产毒率最低,而...     

改性矿物吸附法和O3氧化法对维生素B12废水脱色处理

采用改性矿物吸附法和O3氧化法对某制药厂维生素B12废水进行脱色处理。以废水色度去除率大于50％为目的,通过实验确定改性矿物吸附法和O3氧化法处理维生素B12废水的最佳工艺条件：废水的pH为3．00,有机化膨润土的投加量为5g／L,PAC的投加量为6g／L,投加有机化膨润土后搅拌时间为30min时,废水的色度去除率可达到51．3％,处理成本为12．85元／t。O3氧化法的最佳条件：废水的pH保持不变,O3流量为5g／h,反应时间为2min,废水的色度去除率可达到68．8％,处理成本为0．96元／t。对比这2种方法,O3氧化法处理该废水成本更低、效率更高,并且能提高废水的可生化性以便后续处理。     

混凝—Fenton法深度处理维生素B12废水

采用混凝—Fenton法深度处理维生素B12废水,考察各操作参数对COD和色度去除效果的影响。实验结果表明：当混凝pH 4.5、聚合硫酸铁加入量300 mg/L、氧化pH 4.0、H2O2加入量420 mg/L、FeSO4?7H2O加入量334 mg/L、Fenton反应时间3 h时,混凝—Fenton法对维生素B12废水的深度处理效果较好,总COD和总色度的去除率分别为62.1%和90.0%;与Fenton法相比,混凝—Fenton法COD和色度去除率的提高率分别为17.4%和13.8%,且药剂成本降低了21.6%。