酸性蚀刻废液处理的试验研究

通过室内试验,比较置换、中和-置换及化学沉淀-电絮凝处理方法对废蚀刻液的处理效果.结果表明,化学沉淀-电絮凝工艺的处理效果最好,其适宜工艺条件为废蚀刻液pH=6 0～7 5、电絮凝电流密度50 mA/cm2和电絮凝作用15 min,此时COD和Cu2+的去除率分别达98 7%和99 98%.研究表明,经过化学沉淀-电絮凝工艺处理的酸性蚀刻废液可达到排放标准,同时化学沉淀过程中产生的沉淀物经处理后可得到硫酸铜产品.     

基于改进逼近理想解排序(TOPSIS)法的应急系统优化选址模型研究

通过分析影响应急系统选址的各种因素,建立衡量应急系统地址优劣的指标体系,并利用层次分析法确定各指标的权重。依据改进逼近理想解排序(TOPSIS)法的基本思路,建立应急系统优化选址模型。通过具体的实例说明,将改进TOPSIS法引入选址模型是解决应急系统优化选址问题的有效方法,是选址方法体系的一种创新思路。     

Dehydrochlorination behavior of polyvinyl chloride and utilization of carbon residue: effect of plasticizer and inorganic filler

The dehydrochlorination behavior of plasticizer (DOP) and inorganic filler (CaCO₃) contained in PVC samples and the properties of the activated carbons produced from those carbon residues have been investigated. In the dehydrochlorination process, both additives contributed not only to a decrease in HCl yield but also to the prolonged evolution of HCl. Part of the Cl species were observed to be stabilized as CaCl₂ by reaction with calcium ions when CaCO₃ was added. More than 80% of chlorine removal was achieved in all samples at 533 K. The use of potassium as an activation agent led to the production of activated carbon with a specific surface area greater than 1000 m²/g at the low temperature of 1023 K and assisted also in the elimination of residual Cl species by the formation of KCl during activation. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6     

利用磷化渣配制复合磷化液

采用固体废物磷化渣配制成复合磷化液,并用所配制的复合磷化液对A3钢试件进行磷化处理,形成磷化膜。通过正交实验确定了配制复合磷化液的较佳配方为：磷化液基础液加入量0．2L／L、氧化锌加入量5g／L、碳酸钠加入量6g／L、硝酸加入量12．5mL／L、浓磷酸加入量2．5mL／L、硫酸铜加入量0．3g／L。复合磷化液为浅绿色透明溶液,pH为4．0,总酸度为40,游离酸度为10,磷化温度为65℃,磷化时间为300～600s。所形成的磷化膜厚度为16．0μm,单位质量为26．875g／m^2,粗糙度为1．425μm,维氏硬度为124．27kgf／mm^2。磷化膜硫酸铜点滴时间为35s,耐盐水时间为8h,耐盐雾时间为4h,其物理性质和耐蚀性能均较佳。     

New best estimates for radionuclide solid–liquid distribution coefficients in soils,Part 1: radiostrontium and radiocaesium

Best estimates for the solid-liquid distribution coefficients (K_d) of radiostrontium and radiocaesium for various soil types, were derived from geometric means (GM) calculated from grouping soils by texture and organic matter content, and also using soil cofactors governing soil–radionuclide interaction. The K_d (Sr) GM for Sand, Loam, Clay and Organic groups were similar, although the value for the Sand group was significantly lower. The Sr cofactor approach, based on the ratios of cation exchange capacity (CEC) to Ca and Mg concentrations in the soil solution, leads to K_d (Sr) GM with a lower variability, from which best estimates could be proposed. The K_d (Cs) GM for Sand and Organic groups differed, although similar values were obtained for Loam and Clay groups. Grouping the K_d (Cs) according to the Radiocaesium Interception Potential (RIP) and the RIP divided by the K concentration in the soil solution also allows to suggest K_d (Cs) best estimates with a lower variability.     

6A01-T5铝合金/304不锈钢的缝隙腐蚀行为研究

目的 研究6A01-T5铝合金和304不锈钢异种金属间的缝隙腐蚀行为规律。方法 采用常温常压浸泡腐蚀方法,结合SEM、EDS、XRD和白光干涉检测,对6A01-T5铝合金/304不锈钢缝隙结构在碱性Na Cl溶液中的腐蚀行为进行研究。结果 6A01-T5铝合金/304不锈钢缝隙腐蚀表现为在缝口处产生沿缝口方向的凹陷渠,在缝内,以局部减薄和腐蚀坑为主,并随着腐蚀时间的延长,腐蚀程度逐渐加重。不同区域腐蚀产物的形貌和成分组成不尽相同,缝外暴露区的腐蚀产物表现为晶体颗粒状,主要成分为Ca CO3和Al(OH)3等铝的腐蚀产物。缝口附近沿缝口方向形成一层有明显界线的腐蚀产物覆盖层,缝隙内部的腐蚀产物相对较少,表现为尺寸相对较小的结块,主要成分为Al(OH)3等铝的腐蚀产物。结论 在6A01-T5铝合金与304不锈钢非电连接情况下,6A01-T5铝合金/304不锈钢缝隙内2种金属分别独立发生缝隙腐蚀,因2种金属在腐蚀过程中争夺O2,使得304不锈钢对6A01-T5铝合金的缝隙腐蚀起到抑制作用。     

Effect of salt solution treatment on impurity removal: A case study on phosphogypsum

This study gives a brief demonstration of impurity removal efficiency upon salt solution treatment of phosphogypsum (PG). The experimental set up has been designed according to a multi-variable Box–Behnken Design (BBD) with stirring time, solid: liquid (PG:salt solution) ratio and temperature as the conducted in various salt solutions. PG sample has been treated with sea water, 5% NaCl and 10% NaCl solutions according to the BBD matrix. Fluoride (F), copper (Cu), manganese (Mn), and nickel (Ni) amounts in the PG sample have been measured upon pre- and post-treatment with salt solutions. Among other operating conditions, temperature has been the dominant factor on fluoride removal efficiency, and responses for the factors determined in the experiment runs indicated that a significant correlation could be established between temperature and fluoride removal, sea water being the most efficient salt solution. Higher copper, manganese, and nickel removal efficiencies have been observed in single salt NaCl solution systems however no significant correlation could be established between factors. Results indicate that pre-treatment of PG located near coastal regions with sea water can be a cost-effective approach and applicable on industrial scale when fluoride removal is of importance.     

对《建设项目环境影响评价技术导则总纲》的几点思考

新的环评技术导则总纲实施以来,环评单位根据新总纲要求编制环境影响报告过程中遇到的诸多不确定问题,比如资源能源政策利用、国家产业政策相符性和资源利用合理性、公众参与意见采纳、竣工验收内容和评价结论等在报告中如何体现,意见不一.文章根据环保部技术导则总纲培训并结合报告编制过程中与技术人员的讨论阐述了关于如何严格按照新总纲开展环评工作的几点思考和意见,并提出了相应的解决方案,对以后的环评工作开展有一定的指导意义.     

固体废物浸出液中毒杀芬的分析研究

毒杀芬由于高毒性、高稳定性及生物累积性而备受关注,它由1000多种化合物组成.固废浸出液成分较复杂,建立准确可靠的固体废物浸出液中毒杀芬的分析方法具有重要意义.通过优化毒杀芬分析的色谱分析条件与固体废物浸出液中毒杀芬的前处理方法、探索其定性定量方法,建立了毒杀芬"数量化"的定性模式,最终建立固体废物浸出液中毒杀芬含量的分析方法.所建立方法的校准曲线相关系数大于0.998,检出限为1.16 g·L-1,RSD为5.01%,该方法被用于实际固体废物浸出液中毒杀芬的分析,回收率良好.方法的"数量化"的定性模式有望用于其他混合物的定性分析.     

碱性溶液的脱硫量

在２５℃下实验测定了不同初始ｐＨ值的氢氧化钠和氢氧化钙溶液的脱硫量随ｐＨ值的变化关系；推导出了氢氧化钠和氢氧化钙溶液的脱硫量计算公式。在２５℃下由公式计算出的脱硫量与实验结果基本一致（最大绝对误差小于１ｍｍｏｌ／Ｌ）