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121.
通过对比运行试验,研究了内、外循环EGSB反应器酸碱特征及其调控能力.结果表明,内、外循环厌氧反应器内部的pH值分布规律相似,较低有机负荷时pH值梯度变化较小,较高负荷时随循环比变化pH值分布有所差别,但2种条件下循环比为3时反应器内pH值均可达到较均衡的分布.相同原水pH值条件下外循环体系pH值要高于内循环体系pH值,2种条件下体系pH值变化趋势较为一致,二者平均差值在0.5个单位左右.循环厌氧反应器系统pH值维持在6.3~6.8可以较好地保障系统正常运行,为了保证此条件,外循环运行方式对原水pH值的极限调节范围是4.5~6.8,内循环运行方式对原水pH值的极限调节范围是5.3~7.2.该成果对于研究和应用内外循环EGSB反应器具有理论参考和实用价值. 相似文献
122.
123.
Formation and emission status of PCDDs/PCDFs in municipal solid waste incinerators in Korea 总被引:5,自引:0,他引:5
Kim SC Jeon SH Jung IR Kim KH Kwon MH Kim JH Yi JH Kim SJ You JC Jung DH 《Chemosphere》2001,43(4-7):701-707
This study was carried out to examine the formation and the emission status of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) in the flue gases of commercial-scale municipal solid waste (MSW) incinerators, and thus to provide the engineering data for the reduction of PCDDs/PCDFs emitted from MSW incinerators. The formation concentrations of the PCDDs/PCDFs generated at the outlet of waste heat boilers (WHB) were in the range of 1.18-29.61 ng-TEQ/N m3 (average 5.75 ng-TEQ/N m3), while the emission concentrations at the stacks were in the range of 0.026-4.548 ng-TEQ/N m3 (average 0.924 ng-TEQ/N m3). Two major 2,3,7,8-substituted congeners were 2,3,4,7,8-PeCDF and 2,3,4,6,7,8-HxCDF, and their concentrations were up to 50% and 64% of total TEQ values at the outlet of WHB and the stack, respectively. From the results of multi-regression analysis, the formation concentration of PCDDs/PCDFs could be predicted as follows with the correlation factor of r2 = 0.962: PCDDs/PCDFs (ng-TEQ/N m3) = 3.036 (Cl) + 0.094 (T1) - 0.472 (Combustibles) + 0.059 (CO) - 0.039 (THC) - 3.366 (H) + 22.157, where T1 (degrees C) is the temperature at the outlet of the WHB. Cl, Combustibles and H are given as percentages and the others are in parts per million. 相似文献
124.
由文辉 《生态与农村环境学报》1997,(3)
淀山湖是上海市唯一的淡水湖泊,面积约62km2。淀山湖湿地的形成主要是地质、地貌、气候、水文等自然因素和人类活动影响长期相互作用的结果。本文着重讨论了淀山湖湿地的生产功能和环境生态功能,并对湖泊湿地的利用与保护提供了建议。 相似文献
125.
Min Sun Risheng Yao Yahua You Shengsong Deng Wenxia Gao 《Frontiers of Environmental Science & Engineering》2007,1(1):95-98
This paper reports on the degradation of 4-aminophenol using hydrogen peroxide as oxidizer and the enzyme from Serratia marcescens AB 90027 as catalyst. The effecting factors during degradation and the degrading mechanism were studied. Also, the location of the enzyme in the cell, which could catalyze the degradation of 4-aminophenol, was analyzed. The results showed that to degrade 50 mL of 4-aminophenol whose concentration was 500 mg/L, the optimal conditions were: volume of H2O2 = 3 mL, temperature = 40–60°C and pH = 9–10. In the degradation process, 4-aminophenol was first converted to benzoquinone and NH3, then organic acids including maleic acid, fumaleic acid, and oxalic acid were formed, and then finally CO2 and H2O were generated as final products. The enzyme that could catalyze the degradation of 4-aminophenol was mainly extracellular enzyme. 相似文献
126.
Humic acids, especially FA in fractions, contain more oxygen functional groups. In this experiment, on the basis of confirming the action of humic acids on KBD, what was studied is the biological effects of one of main oxygen functional groups, hydroxy group (-OH). The results indicate that inducing pathologic process of KBD, obviously decrease the GSH-Px activity and induce peroxidation membrane injury of tissue. The SOD activity increase in the tissues caused by oxygen functional groups showed that enhancing of free radical reaction should not be neglected. 相似文献
127.
IntroductionThestudyofmodernsoilzoologyhasenteredintoastageofbiologicalproductivityandtherelationbetweenhumanandenvironment.P?.. 相似文献
128.
散化码头化学品水污染危害性评估模式研究 总被引:3,自引:0,他引:3
提出散化码头三类典型液体化学品水污染危害性评估模式 ,并建立其计算扩散模型。 相似文献
129.
对博尚水库的水质现状、富营养状况、年内变化、年际变化及主要污染物质入库量分析评价,找出污染特性,并针对污染特性提出相应的建议。 相似文献
130.
在水资源日趋紧张的今天,污水的深度处理回用工艺成了人们探讨的热点。结合郑州市五龙口污水处理厂的设计与运行,介绍了以改良氧化沟为主体的污水深度处理回用工艺,并对工艺除磷脱氮及污水深度处理的原理、设计参数、运行情况及运行条件的控制进行了介绍。运行结果表明该工艺既具有较高的COD、SS去除效率,又解决了传统氧化沟在脱氮除磷时存在相互影响的矛盾问题,在进水COD为326mg/L、SS为301mg/L、NH_4~+-N为45.1mg/L、TP为4.1mg/L;出水COD为21mg/L、SS为9mg/L、NH_4~+-N为1.4mg/L、TP为0.6mg/L,各项指标均达到了景观用水标准。 相似文献