Recovery of molybdenum, phosphorus and arsenic fromleaching solution of molybdenum residues by solvent extraction with primary amine and tributylphosphate

Ｒｅｃｏｖｅｒｙｏｆｍｏｌｙｂｄｅｎｕｍ，ｐｈｏｓｐｈｏｒｕｓａｎｄａｒｓｅｎｉｃｆｒｏｍｌｅａｃｈｉｎｇｓｏｌｕｔｉｏｎｏｆｍｏｌｙｂｄｅｎｕｍｒｅｓｉｄｕｅｓｂｙｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｗｉｔｈｐｒｉｍａｒｙａｍｉｎｅａｎｄｔｒｉｂｕｔ...     

Numerical model of compressible gas flow in soil pollution control

ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｄｆｉｌｌｇａｓｗｉｌｌｂｅｇｅｎｅｒａｔｅｄａｆｔｅｒｏｎｅｙｅａｒｏｆｌａｎｄｆｉｌｌｉｎｇｏｆｍｕｎｉｃｉｐａｌｓｏｌｉｄｗａｓｔｅ .ＴｈｅｃｏｍｐｏｎｅｎｔｓｏｆｌａｎｄｆｉｌｌｇａｓａｒｅｍａｉｎｌｙＣＨ4 ,ＣＯ2 ,ｗｉｔｈａｄｄｉｔｉｏｎａｌｓｏｍｅｔｒａｃｅｃｏｎｓｔｉｔｕｔｅｓｓｕｃｈａｓＮ2 ,Ｈ2 ,Ｈ2 Ｓ ,ａｎｄｖｏｌａｔｉｌｅｏｒｇａｎｉｃｃｏｍｐｏｕｎｄａｎｄｓｏｏｎ .Ｌａｎｄｆｉｌｌｇａｓｗｉｌｌｂｅａｃｃｕｍｕｌａｔｅｄｉｎｔｈｅｌａｎｄｆｉｌ…     

水质样品预处理的重要性和几种分析指标的预处理方法

从实验上科学的分析了水质样品预处理的必要性,并从理论和实践上介绍了NH3-N,总氰、苯胺-硝基苯和六价铬几种监测要素的预处理方法.得出结论:只有进行正确的预处理方法,才能得到具有代表性、可比性、完整性、精确性、准确性的结果.     

关于砂金矿露天开采项目环境影响评价的思考

砂金露天矿开采是一种比较特殊的采矿方式,主要是水力淘洗的物理过程,而主要设备是采金船.由于采金船的挖掘作业使大面积的地表生态环境受到严重破坏,造成河流改道,砂砾、岩石垒积,地表土壤、植被几乎全部毁坏,失去植被生长的天然基础,使作业区成为不毛之地.采金船在挖掘作业的同时,内部也在同步进行着水力淘洗砂金的过程,用水量与排水量巨大,特别是排放的高浓度悬浮物废水,恶化了河流水质,如果不采取有效措施降低排入河流中的含高浓度悬浮物的采金废水,则对河流水环境质量与水生生态也将是毁灭性的影响.因此,砂金矿采选项目环境影响评价的重点是对生态环境和水环境的影响.本文根据此类项目的特点,简要分析了此类项目生态环境和水环境影响评价的技术要点及应该注意的问题,并提出生态环境保护与水环境保护措施,为环境影响评价工作提供技术依据.     

用加速溶剂提取仪提取污染土壤中的有机氯农药

研究加速溶剂萃取对土壤中有机氯农药的提取效果,并与索氏提取法进行比较。结果表明,加速溶剂萃取对土壤中滴滴涕的回收率明显高于索氏提取,对土壤中BHC的提取能力与索氏提取相当。用该方法测定了天津污灌区和非污灌区土壤样品中的有机氯农药残留量。结果表明,α-BHC、β-BHC、δ-BHC、γ-BHC、p,p’-DDE、p,p’-DDD、p,p’-DDT、o,p’-DDT的检出率为100％,这些有机氯农药在污灌旱地和稻田地的残留量分别为7．5－71．1ng/g和3．0－16．5ng/g。非污灌的旱地中有机氯农药的残留量为3．1－17．6ng/g。     

Extraction of copper ions by supercritical carbon dioxide

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｍｐｌｅｘａｔｉｏｎｃｏｍｂｉｎｅｄｗｉｔｈｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｈａｓｂｅｅｎｕｓｅｄｔｏｅｘｔｒａｃｔｍｅｔａｌｉｏｎｓｆｒｏｍｓｏｌｉｄｍａｔｒｉｘｓｕｃｈａｓｓｏｉｌｓａｎｄｓｅｄｉｍｅｎｔｓ(Ｍｉｎｃｚｅｗｓｋｉ,1 982 ;Ａｌｆａｓｓｉ,1 992 ) .Ｔｈｅｓｅｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｐｒｏｃｅｄｕｒｅｓｈｏｗｅｖｅｒａｒｅｕｓｕａｌｌｙｔｉｍｅａｎｄｌａｂｏｒ ｉｎｔｅｎｓｉｖｅ.Ｉｎａｄｄｉｔｉｏｎｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｒｅｑｕｉ…     

Assessment of interfacial mass transfer in water-unsaturated soils during vapor extraction

This paper presents results of a numerical investigation of soil vapor extraction (SVE) systems at the laboratory scale. The SVE technique is used to remove volatile chlorinated hydrocarbons (VCHC) from the water-unsaturated soil zone. The developed numerical model solves equations of flow, transport and interfacial mass transfer regarding an isothermal n-component and three-phase system. The mathematical model is based on a simple pore network and phase distribution model and designed to be scaled by a characteristic length. All mathematical expressions are structured into VCHC specific and VCHC non-specific parameters. Furthermore, indicators are introduced that help to separate thermodynamic equilibrium from thermodynamic non-equilibrium domains and to determine the controlling physical parameters. For numerical solution, the system of partial differential equations is discretized by a finite volume method and an implicit Euler time stepping scheme. Computational effort is reduced notably through techniques that enable spatial and temporal adaptivity, through a standard multigrid method as well as through a problem-oriented sparse-matrix storage concept. Computations are carried out in two dimensions regarding the laboratory experiment of Fischer et al. [Water Resour. Res. 32 (12) 1996 3413]. By varying the characteristic length scale of the pore network and phase distribution model, it is shown that the experimental gas phase concentrations cannot be explained only by the volatility and diffusivity of the VCHC. The computational results suggest a sorption process whose significance grows with the aqueous activity of the less or non-polar organic compounds.     

城市污水处理厂不同工艺段中有机氯农药残留

建立了基于HLB固相萃取柱和气相色谱 /电子捕获 (GC/ECD)分析城市污水中有机氯农药的分析方法 ,同时分析了北京市高碑店和北小河两个污水处理厂中 4个不同工艺段水体中有机氯农药的浓度。在两个污水处理厂的水体中共检出了 6种有机氯类农药 ,分别是α 六六六、β 六六六、γ 六六六、δ 六六六、艾氏剂和 4 ,4’ 滴滴滴 ,浓度在 1 89—6 9 6ng/L之间。结果表明 ,曝气活性污泥法对六六六类有机氯农药的去除效果较好。     

络合萃取法处理5-氯水杨酸生产废水的研究与实践

采用络合萃取法处理5-氯水杨酸生产废水,研究了萃取过程中PH、络合剂、稀释剂等对废水革取效果的影响。通过比较,确定以EPT-1为络合剂。试验表明,pH<1.5,按废水:络合剂:稀释剂-100:30:70的比例投加,可取得较好效果。萃取剂连续使用15次,废水的CODCr去除率并无显著下降。多次萃取后萃取剂经氢氧化钠溶液反萃取再生,即可回收萃取剂。     

Composition of torched crude oil organic particulate emitted by refinery and its similarity to atmospheric aerosol in the surrounding area

The absolute contents and relative distributions of organic aerosols [n-alkanes, n-alkanoic and n-alkenoic acids, n-alkan-2-ones and polycyclic aromatic hydrocarbons (PAH)] were determined in torched gases emitted during the crude oil extraction and in the free atmosphere of the Hassi-Messaoud city (Algeria). Monocarboxylic acids, both saturated and monounsaturated (from 9802 to 20 057 ng m⁻³), accounted for the major fraction of the total particulate organic matter identified both in torch exhaust and atmospheric particulate. n-Alkanes were also abundant both in the direct emission (from 460 to 632 ng m⁻³) and city atmosphere (462 ng m⁻³) and displayed a peculiar fingerprint characterised by the presence of a set of branched congeners around even carbon-numbered homologues and a strong even-to-odd predominance along the whole carbon number range (C₁₆–C₃₄). Whilst n-alkan-2-ones were absent in the city and poor in smokes emitted from the torches (from 31 to 42 ng m⁻³), PAH were present at low extents in all sites (from 18 to 65 ng m⁻³). The incomplete thermal combustion of torched crude oil was very likely the main source of these particle-bound organic constituents in the city and its surrounding region.