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451.
生态系统服务价值损失评估是流域突发水污染事件生态损害定量、污染事故责任认定的重要依据.针对流域突发污染事件损失定量问题,基于生态系统服务价值理论,构建了包含不同主导服务偏好的生态系统服务价值损失指标评估方法,提出了受损服务识别、评估指标筛选、损失价值核算三步评估程序,并以浙江省某河段苯酚泄漏事件造成的流域生态系统服务损失为例进行实际测算,结合实例以1-9标度层次分析法(AHP)验证了该方法偏好系数计算方法的可靠性.结果表明,本方法与AHP法的水体生态系统服务损失评估额相对偏差为2.5%,单项指标损失额排序相同,并且在保证评估结果可靠性的前提下更具易操作性优势.  相似文献   
452.
Oxidation of sulfurized rust in oil tank is complicated, and it is influenced by numerous factors such as water content, air humidity, operating temperature etc. The paper focuses on the oxidation process of sulfurized rust in the wild. Firstly, samples collected from a petrochemical company were put into the sulfurization & oxidation experimental apparatus to gain wet and dry sulfurized rusts. Their chemical compositions and phase were analyzed by Energy Dispersive X-ray Spectrometer (EDS) -scanning electron microscope (SEM) technique. The results showed that both wet and dry sulfurized rusts had S, Fe2O3, Fe3S4 and FeS2, whereas FeS only existed in wet sulfurized rust. The two kinds of rusts gave a short length of side, diamond appearance and a large pore size in structure. Then oxidation of wet sulfurized rust was investigated, which included electrochemical reaction stage, electrochemical & chemical reaction coexisting stage and chemical reaction stage. The final oxidation product of wet sulfurized was determined to be Fe2O3. On the basis of this study, an indicator for monitoring and early-warning was proposed to prevent plants in vicinity of the accidental vessel or tank from fire and explosion.  相似文献   
453.
A full-scale compost biofilter system (CBS) was built to treat vapor losses emitted from three analogous vertical fixed roof p-xylene (p-X) liquid storage tanks of 7500 m3 total working volume. The CBS showed a stable and efficient treatment of standing loss (LS) and working loss (LW) with an average removal efficiency of 95.4% through 18-month standing storage and filling operation of the tanks. The weight of activated carbon employed in the concentration buffer influences the CBS performance for LW treatment under high organic loads. The daily average pressure drops across biofilter bed displayed very low with a maximum of 7.6 mm-H2O. This reflects that the CBS can be operated without stress and compression of biofilter bed and thus reduce maintenance frequency. No additional inputs of chemicals and fuels along with low electricity and water usage helped in its prolonged operation and increased its cost effectiveness. These advantages make the CSB become a promising control technology of vapor losses emitted from fixed roof organic liquid storage tanks.  相似文献   
454.
This study investigated a 2010 fire and explosion that occurred at a polypropylene (PP) and copper-clad laminate high-tech plant in Taiwan. Liquid acetone leakage caused the fire and explosion. One person was killed and five were injured; property damage was estimated at US$20 million. In contrast to conventional plants, high-tech plants have sophisticated instrumentation, highly complex pipelines, and confined spaces. In addition, the floor area in a high-tech plant is large and frequently contains a channel through the ground floor to the second or third floor. This channel design enables the fire compartment to be destroyed. Therefore, the system cannot confine the fire to a specific area, thus hindering fire-relief operations. In this study, the original fire outbreak occurred in the PP processing area on the ground floor. The acetone storage tank was located on the third floor. The investigation conducted at the fire site of the situations of the burning (bursting) loss determined that the acetone liquid leaked and dripped from floor cracks and tunnel oven to the PP processing area. Because the PP manufacturing process rapidly generates static electricity, the flammable liquids made contact with the source of ignition, which caused the explosion and fire. Various procedures, such as those involving the operating environment of production, packaging, and processing in a high-tech plant, are likely to produce static electricity in a workplace. Improved electrostatic management can prevent the loss of property and lives, liquid acetone leakage, and loss of equipment caused by static electricity fire.  相似文献   
455.
科学地预测火灾事故及其损失,对于制定火灾防控措施具有重要的现实意义。应用基于马尔科夫的灰色残差GM(1,1)模型,对2002—2011年全国火灾损失进行模拟和预测,结果表明,该模型预测精度明显高于GM(1,1)模型,为火灾损失的预测提供了一种简单而可靠的新途径。  相似文献   
456.
For the handling, treatment and utilization of fly ash from biomass combustion its chemical composition and physical properties are important. In this study eight filter fly ashes from different grate-fired biomass combustion plants were investigated. In fly ash from straw combustion high concentrations of(K) were found, whereas in the fly ash from wood combustion the concentrations of Ca and Mg were higher. The average concentration of PO3-4was similar in both types of fly ashes. In all wood fly ashes some measured heavy metal concentrations were above the limits for utilization. The straw fly ashes were much less contaminated and can be utilized. For wood fly ash most parameters showed little variation, except from one fly ash where the dust pre-separator is in poor condition. The average values were: mass median diameter 4.3 ± 0.8 μm, spread of particle size distribution19 ± 11, particle density 2620 ± 80 kg/m3 and angle of repose 50°± 1°. The density of the straw fly ashes is lower(2260 ± 80 kg/m3) and the spread of the size distribution is higher(72 ± 24).For one straw combustion fly ash the values of the mass median diameter and the angle of repose were similar to the values of wood combustion fly ash, for the other straw fly ash the values differed considerably. While the particle size of this fly ash was much smaller,surprisingly the angle of repose was also lower. This can be attributed to the formation of small agglomerates in this fly ash, which were not disintegrated without a certain stress.  相似文献   
457.
在收集和分析对生态工业发展研究的文献基础上,将影响生态化工产业发展的因素归纳为3大因素:直接因素、间接因素和机制性因素,6个二级指标,分别是自然因素、经济因素、技术因素、产业因素、社会因素、政策法规,同时针对全国第一化工大省山东省不同类型、不同地域的11家化工企业进行了实地调研,并对问卷调研数据进行了基于SPSS软件的克朗巴哈α系数的信度分析以及主成分分析,结果表明问卷具有良好的信度,并按各二级指标中所含因素的重要程度确定了影响生态化工产业发展的12个主要因素,在此基础上提出了化工产业生态化发展的建议,为化工产业生态化建设提供相应的理论支撑。  相似文献   
458.
滤膜法测定悬浮物出现负误差原因研究   总被引:1,自引:0,他引:1  
为了对滤膜法测定水中悬浮物出现负误差的情况进行研究,从滤膜的前处理到滤膜的选择进行了一系列实验,发现主要原因是滤膜在实验的过程中产生失重。对几种微孔滤膜进行了空白实验,得出有机滤膜的空白校正值为0.0000~0.0004g,低于或等于悬浮物的称量误差,此类滤膜用于水中悬浮物的测定,能减少恒重次数,缩短实验时间,提高测定结果的科学性和准确性。  相似文献   
459.
For a pilot-scale application, pH control in the treatment of highly contaminated dye industrial wastewater containing metallic compounds as the main pollutants has been investigated with a method using adaptive heuristic criticism control (AHCC). Subsequent experimentation on between 12 and 18 l of the wastewater was carried out using statistical experimental design methodology to evaluate the effects of three critical factors: slaked lime (calcium hydroxide, Ca(OH)(2)) concentration, iron chloride (FeCl(3)) concentration and wastewater volume. With these critical factors, the wastewater treatment process is modeled as an appropriate quadratic cost function of the turbidity of the clarified water. The model is optimized with Rosenbrock's method. Response surface topology of the wastewater treatment is given in terms of optimal concentrations of lime water and FeCl(3) and optimal wastewater volume at pH 11.  相似文献   
460.
This paper presents an experimental application of AHCC to study the coagulation process of wastewater treatment in a dye plant. Also this study includes a series of tests in which an AHCC control was used for pH control. The performance results of the AHCC controller are compared with the results obtained by using a conventional proportional-integral-derivative (PID) algorithm. It is useful to compare PID with AHCC to illustrate the extreme range of the nonlinearity of the dye wastewater treatment process. Although the removal of pollutants from wastewater is similar with AHCC and PID, our results show excellent AHCC performance in the region where conventional PID control fails.  相似文献   
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