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121.
郭义昌 《安全.健康和环境》2007,7(12):30-31
在石油钻井生产施工过程中,排放大量的固体废弃物、废水、废气,对环境造成污染,危害周围的生态环境.据初步统计,胜利油田陆上钻井产生约1×106t/a钻井废弃物.根据污染控制的原则,一般将污染治理分为源头控制、过程控制和末端治理三种方法,目前常用固液分离、化学固化、废钻井液回收再利用处理技术等末端治理方法,缺陷是处理污染物量大、费用高,容易产生二次污染.我们应用钻井新技术从源头和过程控制污染,实践后取得了明显的效果. 相似文献
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Xiaoyang Fan Yili Wang Daxin Zhang Yajie Guo Shihui Gao Enrui Li Huaili Zheng 《环境科学学报(英文版)》2020,32(5):73-84
The effects of four conditioning approaches:Acid,Acid-zero-valent iron(ZVI)/peroxydisulfate(PMS),Fe(Ⅱ)/PMS and ZVI/PMS,on wastewater activated sludge(WAS) dewatering and organics distribution in supernatant and extracellular polymeric substances(EPS) layers were investigated.The highest reduction in bound water and the most WAS destruction was achieved by Acid-ZVI/PMS,and the optimum conditions were pH 3,ZVI dosage 0.15 g/g dry solid(DS),oxone dosage 0.07 g/g DS and reaction time 10.6 min with the reductions in capillary suction time(CST) and water content(Wc) as 19.67% and 8.49%,respectively.Four conditioning approaches could result in TOC increase in EPS layers and supernatant,and protein(PN) content in tightly bound EPS(TB-EPS).After conditioning,organics in EPS layers could migrate to supernatant.Polysaccharide(PS) was easier to migrate to supernatant than PN.In addition,Acid,Acid-ZVI/PMS or Fe(Ⅱ)/PMS conditioning promoted the release of some polysaccharides containing ring vibrations v P=O,v C-O-C,v C-O-P functional groups from TB-EPS.ESR spectra proved that both radicals of SO_4~-· and·OH contributed to dewatering and organics transformation and migration.CST value of WAS positively correlated with the ratios of PN/PS in LB-EPS and total EPS,while it negatively correlated with TOC,PN content and PS content in TB-EPS,as well as PS content in supernatant and LB-EPS.BWC negatively correlated to zeta potential and TOC value,PN content,and HA content in supernatant. 相似文献
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The application of ultrasonic-electrolysis process for the removal of copper is studied.In the ultrasonic field cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution.Thus increases metal deposition on the cathode surface.The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution. 相似文献
125.
Zhang YJ Bryan ND Livens FR Jones MN 《Environmental pollution (Barking, Essex : 1987)》1997,96(3):361-367
The interactions of a range of actinide elements (Th, U, Np, Pu, Am) with humic substances from the Needle's Eye natural analogue site were studied by gel permeation chromatography. Bulk humic substances were isolated by ammonia extraction, followed by dialysis against distilled water and freeze-drying. The gel permeation results suggest that Needle's Eye humic substances can be fractionated into three incompletely resolved fractions with average molecular weights determined by analytical ultracentrifugation around 49 000 for Fraction 1, around 14 700 for Fraction 2 and around 8000 for Fraction 3. Although there are significant differences between the organic matter elution patterns in individual gel permeation experiments, presumably due to differences in column packing, these are much smaller than the differences between metal ions. The uranium that is naturally present in these humic substances is largely bound in the late-eluting fraction. Spikes of the early actinides, including Np and Pu in controlled valency states, have been added to the humic substances, and gel permeation of the spiked humic substances shows that the three humic fractions vary greatly in their effectiveness and selectivity as ligands for early actinides. 相似文献
126.
The perturbant effects of four Triton adjuvants, namely Triton X-15, X-35, X-100, and X-114 (alkyl aryl polyether alcohols), on some of the biochemical determinants of membrane integrity were determined under laboratory conditions. Two of these, Triton X-100 and X-114, are currently being assessed as emulsifiers for use in fenitrothion insecticidal formulations. Lemna minor L. plants were exposed to 40 microM (10-25 microg ml(-1) in 965 microg mg(-1) Dowanol (tripropylene glycol methyl ether) carrier solvent) adjuvant for a treatment time period of two weeks. A decrease in the contents of the total phospholipids and a concomitant increase in the contents of the galactolipids were found. No change was observed in the total lipid content. An unsaturation occurred in the fatty acids of the total lipids, phospholipids, and monogalactosyl diacylglycerides. This accounted for a significant decrease in palmitic and stearic acids and a concomitant increase in oleic, linoleic, and linolenic acids when these are compared with the fatty acids in the nontreated control sets. The fatty-acid profile of the digalactosyl diacylglycerides, however, differed only slightly from controls. Membrane-fatty-acid unsaturation suggests the possibility of a desaturase enzyme's being induced by these adjuvants. 相似文献
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