武钢技术中心镀锌楼通风装置的改进

论述了镀锌楼通风装置的改进措施,并对改进措施进行了设计计算,实际运行效果良好。     

爆破模型改进及边坡爆破细观过程研究

为了使作者提出的基于颗粒流的爆破模型更贴近于实际,将原模型从二维模拟推广至三维爆破细观模拟。模型的基本原理为基于能量守恒理论,假设爆炸时刻产生的能量全部由爆点周边一定范围内的岩体承受,并转化为动能,进而能量在碎裂的岩块中传递、吸收,最终达到平衡,爆炸过程结束。将原模型方程改为适用于三维爆破模拟方程,并调整了能量分配和参数设置。使用PFC3D模拟了在露天矿边坡内A3爆破点处100kg TNT爆炸直至岩体回复平衡的细观过程。模拟结果表明研究速度矢量、位移矢量和CForce变化趋势后,可将该过程分为3个阶段:Step 1~100、Step100~350、Step350~4690。其时间远小于原模型模拟至平衡时间,这主要是由于模型从二维转化为三维所造成的。颗粒动能减小为原模型的0.085~0.128倍。     

Analysis of gas dispersion and ventilation within a comprehensive CAD model of an offshore platform via computational fluid dynamics

Maintaining an adequate air flow with a desired air quality that is free from hazardous gases is among the most important actions taken toward the improvement of safety in any process plant. Due to the increased focus on the consequences of existing hazardous material on safety, health, and the environment, air quality and sufficient ventilation within a plant has been increasingly considered in the design stage. This paper investigates and analyzes methane and hydrogen sulfite dispersion and the effect of air ventilation within a CAD model of an offshore platform using computation fluids dynamics (CFD). In addition, this method and its principals could be utilized in any other hazardous environment. Simulations of possible hazardous events along with solutions for preventing or reducing their probability are presented to better assess the data. These investigations are performed by considering hypothetical hazardous scenarios which consist of gas leakages from pipes and process equipment under different conditions. After drafting a precise and highly detailed CAD model of the plant and performing CFD simulations on this model, the results of gas behaviors, dispersion, distribution, accumulation, and its possible hazards are investigated and analyzed. The larger amount of details of the actual plant model in CFD simulation are obtained by using a combination of different methods and software. These include PDMS for 3-D drawing of the plan, Rinoceros for geometrical integration of the process equipment and facilities, and Sharc Harpoon which meshes the model. Moreover, the probability of inducing ignitable or toxic concentration of gases within the atmosphere and air ventilation of the unit is considered by these investigations.     

A new methodology for the synthesis of an optimum flexible water networks

This paper presents a new optimization model for the synthesis of direct reuse/recycle water networks with data uncertainties. In this case, data uncertainties were originated from the varying parameters of the water sources and sinks, which fluctuate within a given range of values. The aim of the method is to design an optimum flexible water network (FWN) that ensures minimum fresh water consumption and yet fulfilling all process constraints and uncertain parameters. The resulting FWN also features the minimum number of pipelines, which will ease process operation and control. Due to the complexity of the problem, multistep solving method based on theorem of corner points has been developed. The FWN obtained using the proposed method also includes information on the maximum flow rate in the pipelines, which is essential for detailed network design stage. The resulting model is a mixed integer linear problem (MILP), which may be solved to obtain global optimum solution. Two case studies were used to elucidate the newly proposed method.     

Methods and models in process safety and risk management: Past,present and future

The paper reviews past progress in the development of methods and models for process safety and risk management and highlights the present research trends; also it outlines the opinions of the authors regarding the future research direction in the field. Based on the open literature published in the leading journals in the field of safety, risk and reliability, the review covers the evolution of the methods and models developed for process safety and risk management. The methods and models are categorized as qualitative, semi-quantitative, quantitative and hybrid. The progress in the last few decades is discussed in the context of the past. Developments in the current decade formulate the basis of the present trends; future directions for research in these fields are also outlined. The aim of the article is to provide a historical development in this field with respect to the driving forces behind the development. It is expected that it will help researchers and industrial practitioners to gain a better understanding of the existing concepts. At the same time the aim is to provide direction to bridge the existing gaps through research and developments.     

高速公路交通事故成因分析及对策研究

高速公路因其独特的行车环境 ,其交通事故损失十分巨大 ,研究成因分析具有十分重要的意义。影响高速公路安全的因素很多 ,以往的分析 ,只是从定性的角度 ,没有给出定量方面的具体研究。笔者从系统科学的观点出发 ,对我国高速公路交通事故进行统计分析 ,综合考虑交通参与者、车辆、道路以及行车环境 ,运用层次分析法对主要成因进行分析。结果显示 ,驾驶员因素、外部行车环境 ,尤其是先进的管理技术等占有很大的比重。笔者提出了相关的解决措施及对策建议 ,主观上应该加强对驾驶人员的安全教育培训 ;客观上应该提高车辆、道路的技术水平 ,同时加强高科技技术在事故管理中的应用 ,建立先进的高速公路交通事故管理系统。     

含瓦斯煤岩突出过程数值模拟

含瓦斯煤岩突出是煤炭开采过程中一种复杂的工程诱发灾害。根据煤岩体变形与瓦斯渗流的基本理论 ,考虑煤岩介质材料力学性质的非均匀性特点以及煤岩介质变形破裂过程中透气性的非线性变化特性 ,建立了含瓦斯煤岩突出过程固气耦合作用的RFPA2D Flow模型。利用该模型对石门掘进诱发的含瓦斯煤岩突出进行了初步的数值模拟 ,模拟结果再现了煤岩介质在瓦斯压力、地应力和煤岩力学性质等因素综合作用下由裂纹萌生、扩展、相互作用、贯通直至失稳抛出的突出全过程 ,揭示了采动影响下煤岩介质渐进破坏诱致突变的非线性本质 ,包括含瓦斯煤岩破裂过程中应力场的演化 ,为含瓦斯煤岩突出机理研究提供一套全新的数值试验分析工具。     

铁路提速区段中间站行车安全评价的研究

分析了影响铁路提速区段中间站行车安全的主要因素;基于系统工程的理论原则,从人员安全保障、设备安全保障、环境安全保障、基础安全管理保障4个方面着手,确立了铁路提速区段中间站行车安全评价指标体系;运用模糊层次分析法,建立了评价模型;提出了铁路提速区段中间站行车安全保障模糊层次评价的一般方法;对我国铁路主干线某一提速区段中间站进行实例分析,其结果显示,基础安全管理占有十分重要的位置;最后,笔者建议,在我国铁路实现“客运高速、货运重载”的发展方向下,应当加强提速区段中间站的安全管理,认真进行行车安全评价,实现行车事故的预测与预防     

Assessment of chemical process hazards in early design stages

A new method called SREST-layer-assessment method with automated software tool is presented that in a hierarchical approach reveals the degree of non-ideality of chemical processes with regard to SHE (safety, health and environment) aspects at different layers: the properties of the chemical substances involved (substance assessment layer (SAL)), possible interactions between the substances (reactivity assessment layer (RAL)), possible hazard scenarios resulting from the combination of substances and operating conditions in the various equipments involved (equipment assessment layer (EAL)), and the safety technologies that are required to run a process safely and in accordance with legal regulations (safety-technology assessment layer (STAL)). In RAL, EAL and STAL the main focus is put on process safety. A case study is used to show the principles of the method. It is demonstrated how the method can be used as a systematic tool to support chemical engineers and chemists in evaluating chemical process safety in early process development stages.     

小尺度森林火灾的渐近幂律分布

森林火灾系统是一个自组织临界性系统，它的表现之一就是火灾的尺度分布满足幂律规律。然而实际数据分析表明，在尺度最大和最小的两个区域，火灾分布与幂律规律存在较大的差异。对小尺度火灾的偏离现象，研究者通常猜测是由于小面积火灾记录数据遗漏较多造成的，目前尚没有一个理论上的依据，而小尺度火灾的分布规律对大尺度火灾的预测起看关键作用。为了解释这种偏离现象，该文将火灾看作一个生灭过程，并对火灾蔓延和熄灭的机理进行了分析，最终得到了森林火灾分布与火灾尺度的定量依赖关系及其机理。将该文的结果与日本近年来全国范围内的森林火灾统计数据进行了对比，表明该文得到的结果与真实数据得到较好符合，并且成功解释了小尺度森林火灾分布与幂律关系的偏离现象。该研究可望对深入认识火灾系统的自组织临界性和防治火灾具有一定的实际意义。