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931.
932.
933.
阀门泄漏的原因分析及其设计选型的优化 总被引:2,自引:0,他引:2
张百麟 《石油化工环境保护》2003,26(2):58-61
通过分析各种阀门发生泄漏的原因,以及阀门泄漏对环境和生产所带来的危害,提出在工程设计中的优化阀门选型建议。 相似文献
934.
935.
本文分析了锅炉房噪声的产生机理 ,针对各类锅炉房的具体情况 ,提出了“分散控制”和“集中控制”的不同治理方案。其中隔声、消声、隔振、吸声等声学措施的综合利用 ,易收到较好的效果 ,可降噪 2 0dB(A)以上 相似文献
936.
Heavy metals in surface sediments from Minjiang Esturary—Mazu and Xiamen—Jinmen sea areas 总被引:4,自引:0,他引:4
The concentrations of Cu,Pb, Zn and Cd in surface sediments from Minjang Estuary-Mazu and Ziamen-Jinmen sea areas of China were investigated during 1995-1996.The concentration ranges of Cu,Pb ,Zn and Cd in the Minjiang Estuary-Mazu sea area were 16.4-37.2,33.4-69.6,92.1-128,0.087-0.036mg/kg(dry wt.),respectively; those for Xiamen-Jinmen sea area were 11.0-24.5,36.0-80.3,77.5-161,0.135-0.285mg/kg(dry wt.), respectively.The concentration and distributions of Cu,Pb,Zn and Cd in surface sediments of Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas were analyzed and evaluated.The results showed that the values of Zn and Pb exceeded those of sediment quality criteria.The average concentration of Cu in Minjiang Estuary-Mazu sea area was higher than that in Xiamen-Jinmen sea area.The obviously higher concentrations of Cu,Pb, Zn and Cd were found at outlets of Minjiang and Jiulong River.From the estuaries to open sea, the concentrations of Cu, Pb,Zn and Cd had a decreasing trend, and then elevated in the sea areas near Mazu and Jinmen, suggesting that Cu,Pb,Zn and Cd in Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas may come from both the mainland and Taiwan of China. 相似文献
937.
Experimental data are presented to test and validate a kinetic model for the oxidation of 2-chlorophenol wastewater by photo-assisted Fenton process. The data showed that this process had produced good effects under acidic conductions. Up to 90% 2-chlorophenol was removed after 90-minute reaction time with H2O2 of 25% CODCr. in, while in UV/H2O2 system ordy 16.8% 2-chlorophenol was removed after one hour treatment. The optimal pH in this reaction occurred between pH 3.0 and pH 4.0. The reaction kinetics for photo-assisted Fenton process experimented in this research was investigated. Kinetic models were proposed for the treatment of 2-chlorophenol wastewater. The reaction was found to follow the 2nd order. The equations of reaction kinetics are as follows:-d[RH]/dt=KRH[RH][H2O2]0exp(-KH2o2t);-d[CODCr]/dt=KCODCr[CODCr][H2O2]0exp(-K′t).The prediction of the models was found to be in a good agreement with experimental results, thus confimfing the proposed reaction mechanism. 相似文献
938.
IntroductionChlorinatedorganiccompoundshavebeenusedonalargescaleinthechemical,petrochemical,andelectronicindustries.Inrecentyears ,worldwideattentionhasbeengiventotheenvironmentalandhealthimpactofthemasaclassofcontaminants .Severalareknowntocauseozonedepletion ,whileothersproduceadverseeffectsonthehumancentralnervoussystemandhavebeenlinkedtodiseasessuchascancer.Almostallofthechlorinatedaromaticcompoundsaretoxicandthermallystable .Oncereleasedintoenvironment,theywillaccumulateinthesurroundings… 相似文献
939.
The preparation of immobilizing-catalysts for decomposing ozone by using dipping method was studied. XRD, XPS and TEM were used to characterize the catalysts. The three kinds of catalysts were selected preferentially, and their catalytic activities were investigated. The results showed that the catalyst with activated carbon dipping acetate( active components are Mn:Cu = 3:2, active component proportion in catalyst is 15%, calcination temperature is 200℃ ) has the best catalytic activity for ozone decomposing. One gram of catalyst can decompose 17.6g ozone at initial ozone concentration of 2.5g/m^3 and the residence time in reactor of 0.1s. The experimental results also indicated that humidity of reaction system had negative effect on catalytic activity. 相似文献
940.
通过现场中试对水解过程有机物的降解和SS去除情况进行分析,并通过批量实验对比了水解前后污水的反硝化速率。结果表明:采用厌氧水解取代初沉池作为生物脱氮的预处理工艺,可以有效提高后续生物处理工艺的效率,并可补充一定量的反硝化碳源。 相似文献