Integrating flare gas with cogeneration systems: Operational risk assessment

Flare gas utilization in a cogeneration plant is an attractive proposition considering its environmental and economic incentives. Evaluation of the operational risk of integrating flare gas with cogeneration is complex due to the uncertainty in flare gas quality and process conditions. The current study delves into the change in operational risk after modifying the existing cogeneration process with the addition of fuel from flare gas. Based on the process hazards evaluation, the current study identified two critical loss control events (or top events) - boiler gas temperature exceeding operating design temperature and rich fuel mixture in the boiler firebox. The underlying causes that may contribute and lead to these loss control events were identified using fault trees and were updated to the existing cogeneration scenarios. Similarly, different consequential events that may arise from the loss control events were analysed using event trees with existing system safeguards. A Bayesian network model with its explanatory power mapped all the identified dangerous scenarios from the fault trees and event trees to predict integrated systems reliability and diagnose causal factors. Bayesian Network analysis illustrates the dynamic cause-effect relationship and determines the risk escalation due to the changes in the composition of flare gas that is fed to the boiler. The presence of a higher percentage of hydrogen (above 40 mol%) in the flare gas escalates the risk of lean air to fuel ratio in the boiler firebox and increases boiler radiation zone duty. These conditions are detrimental to the boiler firebox operation and can result in critical scenarios such as flame impingement and tube rupture. Additionally, other consequences-a steam explosion and boiler stack explosion were also investigated. However, their probability of occurrence was relatively insignificant with the given frequency of flare gas utilization in the cogeneration system.     

山东省水质自动监测系统运行管理

结合山东省实际,分析了水质自动监测的运行管理模式。探索了该模式下的质量保证和质量控制措施,包括成立运行管理专门机构,规范监管单位监督管理,严格运维和保障单位管理,强化现场端设备管理。从统一监测数据审核确认和强化自动监测数据应用方面,介绍了山东省水质自动监测数据应用情况,并提出了存在的问题和工作建议。     

学科建制化视角下的中国消防工程学科

消防工程学科在中国基本上已完成了自身的建制化过程。笔者以中国消防工程学科建制化为切入点 ,分析了中国消防学科建制化的过程及其驱动模式 ;同时基于学术期刊在科学事业中地位和历史作用的分析 ,探讨了学术杂志与消防工程学科的关系 ,认为创建权威的学科杂志、进行研究生教育是使消防工程学科建制更加完善的必要条件之一 ;指出中国现有的消防学科的设置已不适应该学科在中国发展的现状 ,需要调整学科设置 ;认为消防学科正面临着自身再建制化的机遇。笔者强调 ,我国火灾科学国家重点实验室的建立与中国火灾科学的兴起 ,不仅标志着消防工程学科知识体系的形成 ,而且使发端于权力系统的消防工程学科建制化过程具备了学术权威学科建制化或再建制化的结构。     

“安全科学学”理论与实践——20世纪80年代安全科学学科在我国初创纪实

从劳动保护科学概念人手，介绍了“安全技术与工程学”学科、专业的诞生过程，较详实地记录了20世纪80年代安全科学学科初创的始末。从中国劳动保护科学技术学会成立与安全工程试办专业的确立到安全科学学科概念及安全科学技术体系结构模型的提出，见证了从理论探索到实践认识提高与应用的过程。安全科学学科创建时期是我国安全科学理论与实践的一个重要阶段。     

中国安全专业教育的现状及拓展方向探讨

安全专业教育是培养专业安全人才的最主要途径。在回顾安全专业教育的发展过程及经验教训的基础上 ,分析了当前存在的问题 ,并对安全专业教育今后发展趋势与拓展方向进行了较为全面的探讨。提出了解决问题的基本手段 ;指出了社会发展对安全类人才的需求趋势预示了安全专业教育向人类生产、生活、生存的其它相关领域的拓展 ;给出了加强与交通、建筑、消防、保险等方面沟通合作的基本设想。     

经济学帝国主义与人口资源环境经济学学科发展

与主流经济学与时俱进是人口、资源环境经济学生存和发展的根基。通过人口、资源与环境经济学兴起和发展的简单回顾和相关研究成功案例的介绍，分析了经济学帝国主义对人口、资源与环境经济学学科发展的启示。提出高举经济学大旗，建立与主流经济学与时俱进的人口、资源与环境经济学。     

再论在《授予博士、硕士学位和培养研究生的学科、专业目录》中设立“安全科学与工程”一级学科

从社会必要性、现实可行性、学科的实践基础、学科的科学基础、学科的结构体系等方面,对在《授予博士、硕士学位和培养研究生的学科、专业目录》中设立“安全科学与工程”一级学科进行了论述,提出了“安全科学与工程”下设二级学科、专业的框架;阐述了“安全科学与工程”和其他与安全学科相关学科的关系、生源关系、与现有安全学科相关的二级学科的关系、与现有安全学科相关的二级学科的学位授予关系以及与其他学科的学缘关系。论证结论表明目前设立“安全科学与工程”一级学科,条件已经成熟。建议国务院学位委员会尽快将“安全科学与工程”单列为一级学科,并在其下设“安全科学”、“安全工程”2个二级学科、专业。     

Implementing an effective conduct of operations and operational discipline program

This paper introduces the concepts of conduct of operations (COO) and operational discipline (OD), the attributes of effective COO/OD systems, and the steps an organization might take to improve its COO/OD programs. In general, the COO program encompasses the management systems developed to encourage performance of all tasks in a consistent, appropriate manner. OD is the deliberate and structured execution of the COO management systems by personnel throughout the organization. By introducing a framework and tools for describing, evaluating, and improving COO/OD, this paper provides guidance that can be used by companies to improve process safety performance.     

Experimental assessment of ecological and phenotypic factors affecting male mating success and polyandry in northern watersnakes, Nerodia sipedon

To resolve conflicting field observations regarding the action of sexual selection, we used breeding experiments and paternity analysis of the 927 resulting offspring to assess how male size, condition, tail length, genetic similarity to the female, and variation in operational sex ratio (OSR) affected male reproductive success and the incidence of polyandry in northern watersnakes (Nerodia sipedon). Only size affected male mating success. Large males were more successful, but only when male size varied substantially and competition among males was intense (i.e., male-biased OSR). The conditional nature of the size advantage may explain why studies of free-living watersnakes have produced inconsistent results regarding the relationship between male size and mating success. Size differences between males did not affect the proportion of offspring each male sired within multiply sired litters. We found positive size-assortative mating, but only when the OSR was female biased, suggesting that smaller males had improved access to females when competition among males was reduced, but that competition with larger males still restricted mating opportunities of small males to less preferred, smaller females. Most litters (58%) were multiply sired and larger females were more likely to produce multiply sired litters, similar to free-living watersnakes. There was no association between the incidence of multiple paternity and OSR, however, suggesting that polyandry is not simply a function of opportunity, with females passively waiting for males to court them.     

力学学科在安全工程专业课程体系中的设置与探讨

在安全工程专业的培养计划中,如何设置力学类课程,使其在安全工程专业各研究分支领域发挥应有的作用,是安全教育工作者所关注和深思的问题。笔者通过调研国内若干大学安全工程专业,力学类基础和专业基础课程的设置情况,对资料与数据的统计分析与对比,认为力学类课程与安全工程技术、职业安全检测技术、劳动保护与器材、安全人机工程等研究方向有紧密关系;提出了力学学科是安全工程和技术科学的重要基础的观点;同时指出力学类课程作为基础和专业基础课,在安全工程专业培养计划中有其重要性;还对安全工程专业各具体分支的力学类课程的设置与教学侧重点提出了建议和探讨。