中国1991~2010年环境污染事故频数动态变化因素分解

运用因素分解方法,将影响环境污染事故频数变化的因素分解为经济规模、污染治理资金规模和风险控制技术水平,构建了环境污染事故频数变化的完全分解模型,并对我国1991~2010年的数据进行实证分析.结果表明:环境污染事故年度间变化均值为-138起.其中,由经济规模、污染治理投资规模和风险控制技术水平所引起的频数变化分别为279起,-74起和-344起.总的看来:该时期经济规模增长对污染事故频数增加起到促进作用,但随着经济规模的增加,该效应对污染事故频数的促进作用减弱;1991~2005年污染治理投资效应有一定的随机性,对污染事故频数的增加基本起到遏制作用;风险控制技术效应对污染事故频数的增加起到遏制作用.环境污染事故频数变化是由各因素共同作用的结果,在不同时期各因素对污染事故频数变化所发挥的效应不同.     

Radionuclide release and transport from nuclear underground tests performed at Mururoa and Fangataufa — predictions under uncertainty

In the context of a study by the International Geomechanical Commission (IGC) and the International Atomic Energy Agency (IAEA) on the effects of nuclear tests at the atolls of Mururoa and Fangataufa, release to the biosphere is estimated for 35 radionuclides originating from 147 nuclear underground tests. Based on a qualitatively characterised hydrogeological situation of atolls and relatively scarce site-specific data, a model chain was developed to conservatively estimate the radionuclide fluxes via groundwater, from their sources, the explosion cavities, towards the biosphere, the ocean or lagoon.Finite element hydro-thermal modelling was used to describe water flow. Parameters were calibrated by a very few measured pre-test temperature profiles in bore holes. The impact of the tests on groundwater flow and mechanical impact on rock was considered. Estimates were made to quantify spatial extensions and temporal evolution of impact by using measurements on refilling rate of the cavities. Tests were categorised according to their specific yield and location although detailed data were missing. A base case parameter set was defined for the hydraulic conditions and for the initial radionuclide inventory of individual tests. Models were used to describe the concentration of radionuclides in the cavities as a function of time. Radionuclide transport from the cavities to the biosphere was represented by two different approaches: a double porosity model for the fractured volcanic rock and a single porosity model for the overlaying, highly porous carbonates. Results consist of conservative estimates on radionuclide release into the environment, or concentration in the lagoon or ocean water. Their sensitivity was investigated using different models and parameters. A few measured data (concentrations in a few cavities, in the deep carbonates and in the lagoons for selected radionuclides, such as ³H, ¹⁴C, ³⁶Cl, ⁹⁰Sr, ¹²⁹I, ¹³⁷Cs²³⁹, ²⁴⁰Pu and ²⁴¹Am) were available for a comparison with the calculations. In view of the lack and uncertainty of site-specific data, the agreement is of acceptable quality.     

氢气爆燃作用下核电站安全壳力学响应数值模拟分析

在核电站严重事故中,由氢气爆燃产生的压力载荷会危及安全壳完整性致其失效,进而造成放射性物质泄漏的严重危害。通过ANSYS/Fluent有限元数值模拟软件,建立了安全壳有限元模型,并对安全壳内氢气爆燃过程以及其力学特性进行了数值模拟研究,获得了氢气爆炸过程中的超压值、升压速率、安全壳变形以及压应力分布。结果表明:爆燃波传递引起压强升高,火焰阵面处压强最高,爆燃波所经区域超压疾速上升随后快速下降;爆燃作用下,顶部壳体和下部筒体连接区域混凝土位移最大,最大压应力也集中分布在该区域,最易受到破坏。获得的结论可为安全壳结构抗爆设计和安全性研究提供理论参考。     

企业重大危险源的识别与控制

本文主要介绍企业开展重大危险源、事故隐患的辨识、评价、监控、预警、应急预案的理论和技术研究．以加快企业持续推动科学发展、安全发展的进程。     

钢铁企业安全生产现状与问题分析

随着我国钢铁企业安全生产标准化的不断深入开展，钢铁企业安全生产状况趋于稳步好转。本文分析了钢铁企业安全生产的现状，并就近年来大中型钢铁企业安全生产事故情况进行了统计分析，对存在的问题进行了深入的探讨，提出了相应的改进对策与建议。     

Nuclear Wastes in the Arctic Ocean. the Consequences of Past Dumping and Opportunities for Future Prevention

The view is expressed that the assessment of disposal of nuclear waste in the ocean (specifically the Arctic and Kara Seas) is critical to understanding Arctic pollution. Much needs to be done in deciding what we should do, even though many wastes are long-standing and persistent. in 1993, disclosures about Russian dumping of submarine nuclear reactors, nuclear fuel, and other radioactive wastes into the Arctic Ocean brought this region and its problems into the world spotlight and raised public concerns about the resulting health and environmental risks. As a result of this concern, the Congressional Office of Technology Assessment published a 1995 study, Nuclear Wastes in the Arctic (US Congress Office of Technology Assessment, 1995). This paper summarises and updates that study.     

环境风险评价中泄漏类重大事故的筛选研究

提出了采用"风险排序,以平均风险指数为尺度"来筛选项目中泄漏类重大事故的方法。该方法是对工业事故风险评估方法(ARAMIS)采用的风险严重度指数法的修正和应用范围的推广。借助已有事故发生的概率统计值,对所引概率进行修正,用Risk System预测得到的半致死浓度范围表征事故的后果。基于概率与后果提出风险指数概念,对各事故风险排序;以平均风险指数为尺度筛选出重大事故。采用该方法对某化工项目环境风险评价中重大事故进行了筛选,此方法与修正前的方法计算的结果一致。方法简单易行,为定量确定单个项目中泄漏类重大事故提供了依据。     

危险化学品运输事故历史数据研究综述

系统地回顾国内外近20 a来的危险化学品运输事故历史数据分析的理论和方法,旨在为我国今后危险化学品运输风险研究提供指导。调研国内外危险化学品运输事故研究的历史数据来源,介绍该领域的主要研究方法及其发展过程,讨论现有研究内容及研究结果的共性和特征。发现现有研究主要集中于危险化学品的道路运输,侧重于分析运输事故的主要影响因素,经济损失、次生灾害及事故数与运输批次的关联方面的研究不足。提出要把事故后果的科学衡量作为未来的研究方向。     

大亚湾区石油化工企业安全生产检查结果分析

2012年6月-7月,32位专家对大亚湾区内28家石油化工企业进行了安全生产检查。检查共发现问题762项,其中事故隐患338项,建议424项。本文对大亚湾区石油化工企业安全生产检查结果进行了研究分析,表明大亚湾石化区整体的安全生产水平较高,安全管理较严格,生产装置工艺成熟,安全保护和防护措施到位。检查同时发现个别企业存在较大的安全生产隐患,需要立即整改。本文对检查中发现的共性问题和较严重问题进行了总结分析,并提出了相应的对策、措施和建议,为政府部门监管、企业整改提供参考和依据。     

石油开采过程中危险化学品的危险特性及事故类型

分析了原油、天然气、液化气、轻质油等危险化学品的危险特性,提出了可能引发的井喷、火灾、爆炸、中毒、环境污染等事故发生的机理.