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301.
通过HAZOP分析对苯储罐进行安全评估,辨识出该储罐在设计阶段潜在的安全隐患,以及在日常操作过程中可能存在的危险源,并提出相应的建议措施,以保障苯罐区的安全平稳运行。同时,通过HAZOP分析能够使得分析人员对工艺流程及危险因素有更加清晰的认识,对苯罐区的日常维护和安全管理提供指导。  相似文献   
302.
安太堡露天矿排土场表层岩土的径流特征与复垦种植研究   总被引:1,自引:0,他引:1  
采用针孔式小型人工降雨机,分别模拟山西塞北高原90~60min,60~45min,45~30min,30~15min各时段降水量极大值,探讨大型露天矿排土场各种排土工艺下地表岩土的径流特征,以指导排土工艺和复垦种植。  相似文献   
303.
柴希娟  孙可伟  王木平 《环境工程》2007,25(1):59-60,63
研究填料粒径和用量对聚乙烯/造纸污泥废弃物复合材料力学性能的影响。采用氢氧化钠和KH-550硅烷作为填料的表面处理剂,马来酸酐接枝聚乙烯作为体系的相容剂改善复合材料的综合性能。实验结果表明,这2种方法均可不同程度地提高复合材料的力学性能,马来酸酐接枝聚乙烯的加入可以有效改善基体与填料之间的相互作用。  相似文献   
304.
以葡萄酒蒸馏废水的厌氧生物处理为例,研究了Fe、Ni、Co、Mo、Cu、Zn对厌氧反应器的COD去除率、出水中挥发性有机酸含量、气体产量、气体成分、pH缓冲能力和碱度等的影响.对比了微量金属投加前后,厌氧反应器污泥中微量金属含量的变化.得出微量金属具有提高厌氧运行效果的作用,其中,Co的作用要更大一些.Ni、Co、Mo在附着态、悬浮态污泥中具有逐渐积累的特点;Fe、Cu、Zn在附着态污泥中是淋失的,而在悬浮态污泥中变化不大.  相似文献   
305.
This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.  相似文献   
306.
Concentrations of 32 elements, Ag, As, Au, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb, and Zn were determined by instrumental neutron activation analysis (INAA) in the early preserved epiphytic lichens (Parmotrema recticulatum) from the remote southwestern China area in the 1960s, 1980s and 1990s. The concentrations of Ag, As, Ce, Cr, Cs, Eu, Fe, Hf, La, Nd, Ni, Sc, Se, Sm, Tb, U, Yb and Zn were dropped down by the temporal prolongation. The elemental concentration levels obtained from the organisms indicate that the extent of heavy metal atmospheric deposition among the sampling sites has been declining during the past decades.  相似文献   
307.
MSW(城市固体废物)生物反应器型填埋是一种较新颖的方法。在系统分析现有填埋方法优缺点的基础上,对其加以改进,将强制通风好氧和渗滤液循环2种方式有机地结合在一起,构建了MSW好氧生物反应器。考察了NH3、CH4、CO2、pH和温度等因素,并监测分析了渗滤液中的COD、BOD5、Zn2+、NH4+和NO3-等指标,旨在研究其中垃圾的降解及渗滤液中COD、BOD5、Zn2+、NH4+和NO3-的去除情况,探讨该生物反应器对垃圾和渗滤液相关参数的作用机理。结果表明,该反应器对渗滤液中COD、BOD5、NO3-的去除率分别达到96.34%、94.58%和99.9%,对其中的Zn2+也有较好的脱除效果。  相似文献   
308.
Air concentrations of volatile organic compounds (VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and 9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most (36.15%) to the total propene-equivalent concentration of the measured VOCs, followed by combustion emission (16.92%), vegetation emission and secondary formation (14.33%), solvent usage (10.59%), petrochemical industry emission (9.89%), petrol evaporation (6.28%), and liquefied petroleum gas (LPG) usage (5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics, e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O3 pollution in Shenyang.  相似文献   
309.
低纬度高原特殊地形影响下的云和降水与其它地区相比有一些独特的情形,中-y尺度暴雨就是特征鲜明的一类,由此系统引发的降水突发性较强,常造成灾害.利用常规高空资料、卫星资料、加密乡镇雨量站资料和新一代多普勒雷达资料,对2010年7月13日云南昭通小河镇灾害性天气分析发现:短时性、高强度,在降水开始的1 h左右就达到暴雨量级,是此次过程的降水特点;中低层风向辐合、高冷低暖、整层潮湿,低层偏南暖湿气流输送水汽及对流不稳定能量堆积,以及边界层辐合线的触发提供了中尺度天气背景;强中尺度对流系统(MCS)是此次暴雨形成的云图中尺度特征;多普勒雷达观测资料分析表明,镶嵌在中-β尺度上的中-γ尺度单体为形成强降水的直接影响系统,该类系统以"单体合并型"和"自壮大升尺度型"居多,且"单体合并型"占较大比例;单体组织化合并可能是部分这类暴雨的触发与维持机制之一.  相似文献   
310.
温度对蚯蚓处理城镇污泥稳定化过程的影响   总被引:3,自引:1,他引:2  
在蚯蚓堆肥过程中,温度会对微生物和蚯蚓活性产生影响,进而影响堆肥效率.将城镇脱水污泥制成5 mm的颗粒,通过比较3个温度条件下(15、20、25℃)赤子爱胜蚓(Eisenia foetida)处理城镇污泥过程中理化、生化指标的变化,研究温度对蚯蚓堆肥稳定化过程的影响.结果显示,在整个稳定化过程中,随温度升高,有机质(OM)、微生物量碳(MBC)降低,电导率(EC)、NH_4~+-N、NO_3~--N升高,而脱氢酶活性(DHA)随温度变化不具有明显规律性.主成分分析(PCA)结果表明,蚯蚓堆肥稳定化过程依次经历以有机质生物降解、氨化和硝化为特征的3个阶段.以蚯蚓适宜生长温度控制蚯蚓堆肥,将更有利于蚯蚓与微生物协同作用的高效发挥.温度能改变蚯蚓堆肥的稳定化效率,但并不改变稳定化路径.  相似文献   
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