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51.
新型生物质活性炭烟气脱硫研究   总被引:2,自引:0,他引:2  
刘洁岭  汤争光  陈杰  蒋文举  江霞 《环境科学》2013,34(4):1623-1627
以农业废弃物核桃壳为原料,天然软锰矿为添加剂共混制备得到的新型生物质柱状活性炭进行烟气脱硫的性能研究.采用固定床反应器进行脱硫实验,装填活性炭质量为16 g,考察了进口SO2含量、空速、床层温度、水蒸气和氧气含量等工艺参数对活性炭脱硫性能的影响.结果表明,进口SO2含量在0.1%~0.3%(体积含量)范围内时,活性炭的穿透硫容和穿透时间随着进口SO2含量的升高而降低;空速越大,活性炭越容易穿透,较佳的空速为600 h-1;最适的床层温度为80℃,过高会降低脱硫效率;水蒸气和氧气的存在大大促进了活性炭对SO2的吸附性能,最佳水蒸气含量为10%,最佳氧气含量为10%~13%.在最佳工艺操作条件下,当进口SO2含量为0.2%时,活性炭穿透硫容为252 mg.g-1,穿透时间可达26 h.  相似文献   
52.
This paper presents a simulation analysis of the explosions following an LPG leak and visualizes the consequences of the accident to reduce the consequences of the LPG leak explosion. Firstly, this paper proposes a CFD numerical simulation-based method for visualizing the consequences of LPG tanker failure. The method combines satellite maps and CFD numerical simulation data to visualize the consequences of LPG leaks and explosions, taking into account the influence of obstacles on the danger range of leaks and explosions; Secondly, this paper applies the method to a liquefied petroleum gas accident that occurred in the Wenling section of the Shenhai Expressway and performs CFD numerical simulation on the accident process and visualizes the consequences of the accident. Therefore, this method can provide a theoretical reference for the prior prevention of LPG accidents and the analysis of the consequences of accidents, as well as certain practical guidance instructive.  相似文献   
53.
Natural gas pipeline construction is developing rapidly worldwide to meet the needs of international and domestic energy transportation. Meanwhile, leakage accidents occur to natural gas pipelines frequently due to mechanical failure, personal operation errors, etc., and induce huge economic property loss, environmental damages, and even casualties. However, few models have been developed to describe the evolution process of natural gas pipeline leakage accidents (NGPLA) and assess their corresponding consequences and influencing factors quantitatively. Therefore, this study aims to propose a comprehensive risk analysis model, named EDIB (ET-DEMATEL-ISM-BN) model, which can be employed to analyze the accident evolution process of NGPLA and conduct probabilistic risk assessments of NGPLA with the consideration of multiple influencing factors. In the proposed integrated model, event tree analysis (ET) is employed to analyze the evolution process of NGPLA before the influencing factors of accident evolution can be identified with the help of accident reports. Then, the combination of DEMATEL (Decision-making Trial and Evaluation Laboratory) and ISM (Interpretative Structural Modeling) is used to determine the relationship among accident evolution events of NGPLA and obtain a hierarchical network, which can be employed to support the construction of a Bayesian network (BN) model. The prior conditional probabilities of the BN model were determined based on the data analysis of 773 accident reports or expert judgment with the help of the Dempster-Shafer evidence theory. Finally, the developed BN model was used to conduct accident evolution scenario analysis and influencing factor sensitivity analysis with respect to secondary accidents (fire, vapor cloud explosion, and asphyxia or poisoning). The results show that ignition is the most critical influencing factor leading to secondary accidents. The occurrence time and occurrence location of NGPLA mainly affect the efficiency of emergency response and further influence the accident consequence. Meanwhile, the weight ranking of economic loss, environmental influence, and casualties on social influence is determined with respect to NGPLAs.  相似文献   
54.
The disaster scene in three-dimensional (3D) plays a crucial role in disaster emergency management and risk communication of oil transmission stations. However, existing research for the disaster scene mainly focuses on reproducing the disaster environment and rarely predicts the damage state of the disaster-affected object. This paper proposes an object-oriented modeling method that utilizes a multilevel decomposition pattern for disaster scenes. This method combines earthquake vulnerability assessment with 3D visualization technology to predict and characterize the damage state of critical infrastructure in oil transmission stations. To enhance earthquake risk perception, a simulation system is designed and developed, which allows for the construction of virtual scenes and quick simulation of disaster scenes in 3D. The case application shows that the system improves the 3D modeling efficiency of disaster scenes and enhances public awareness of earthquake risks. The simulation system can provide technical support for seismic mitigation planning and emergency management decision-making at oil transmission stations and has good application prospects.  相似文献   
55.
为了探究煤与瓦斯突出过程中煤体层裂演化特征,利用自主研制的煤与瓦斯突出实验模拟系统,研究突出过程中煤体层裂结构特征、煤体裂隙厚度演化特征和煤体质点运动演化特征。研究结果表明:在轴向应力0.9 MPa、瓦斯压力0.4 MPa时,煤体层裂发展时间持续85 ms,煤体共计出现11处裂隙。层裂从煤体后方的弱构面出现并向前方发展,其位置大多集中于突出腔体中后部,煤体层裂形式均为纵向贯通,在第9处出现最大纵向断裂裂隙。煤体裂隙总厚度约为75.6 mm、单处裂隙平均厚度约为8.4 mm,二者均呈现随时间递增的趋势。层裂过程中煤体单处裂隙厚度并不都是沿程递增的,部分煤体中部裂隙厚度呈现先增大后减小的特征。煤体的运动表现为靠近突出口端的运动速度更快、运动距离也更长。研究结果可为揭示煤与瓦斯突出层裂机制提供参考。  相似文献   
56.
为确定燃气管网风险评估的关键风险因素,以A省各地市燃气管网为研究对象,基于燃气专家经验确定燃气管线风险等级,提出基于Logistic回归的燃气管网风险因素重要度分析方法。采用样本增强及随机抽样的方式,选取400个均衡样本作为管网评估数据输入,通过因子分析方法对其进行降维,得到3个公共因子并作为一级指标反向构建燃气管网风险评估指标体系;利用有序多分类Logistic回归方法,根据回归系数绝对值大小对风险因素进行重要度排序。研究结果表明:外界环境对燃气管网风险的贡献程度相对较高,管道自身因素和巡检养护次之。研究结果可为城市燃气风险防控提供理论依据和方法参考。  相似文献   
57.
浅析废烟气脱硝催化剂环境管理   总被引:1,自引:0,他引:1  
随着"十二五"期间国家对氮氧化物排放的控制越来越严格,选择性催化还原(SCR)烟气脱硝技术被广泛应用于火电厂的脱硝工程。本文介绍我国目前废烟气脱硝催化剂的产生情况、存在的环境风险以及发达国家的管理经验,从而提出我国将废烟气脱硝催化剂纳入危险废物管理,推行危险废物经营许可证制度,加强产生和经营单位的日常监督管理,从而促进行业的健康可持续发展。  相似文献   
58.
Loss of the underground gas storage process can have significant effects, and risk analysis is critical for maintaining the integrity of the underground gas storage process and reducing potential accidents. This paper focuses on the dynamic risk assessment method for the underground gas storage process. First, the underground gas storage process data is combined to create a database, and the fault tree of the underground gas storage facility is built by identifying the risk factors of the underground gas storage facility and mapping them into a Bayesian network. To eliminate the subjectivity in the process of determining the failure probability level of basic events, fuzzy numbers are introduced to determine the prior probability of the Bayesian network. Then, causal and diagnostic reasoning is performed on the Bayesian network to determine the failure level of the underground gas storage facilities. Based on the rate of change of prior and posterior probabilities, sensitivity and impact analysis are combined to determine the significant risk factors and possible failure paths. In addition, the time factor is introduced to build a dynamic Bayesian network to perform dynamic assessment and analysis of underground gas storage facilities. Finally, the dynamic risk assessment method is applied to underground gas storage facilities in depleted oil and gas reservoirs. A dynamic risk evaluation model for underground gas storage facilities is built to simulate and validate the dynamic risk evaluation method based on the Bayesian network. The results show that the proposed method has practical value for improving underground gas storage process safety.  相似文献   
59.
气相色谱法测定废水中6种挥发性脂肪酸含量   总被引:1,自引:0,他引:1  
挥发性脂肪酸(VFA)是厌氧消化过程的重要中间产物,在反应器运行中,出水VFA用作重要的控制指标。通过色谱条件探索将各种脂肪酸分离,同时研究了水样酸碱度,吸附等对测定的影响,进一步优化了废水中挥发性脂肪酸的测定。方法的检出限在0.99~1.77 mg/L,回收率在90.9%~102.7%之间,相对标准差(n=5)在1.3%~3.8%之间。  相似文献   
60.
Fenton试剂的氧化能力强,反应过程短,降解效果好,本文中介绍了Fenton试剂的特点,并且通过实验得出几种无机离子对Fenton试剂氧化处理工业废水的影响。  相似文献   
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