从一起爆炸事故谈作业安全票证(单)的管理

从一起爆炸事故的原因--没有办理设备检修许可证,分析了使用作业安全票证(单)存在的问题,提出了加强作业安全票证(单)管理措施.     

氯碱企业生产过程中的重大危害分析及对策

分析了氯碱企业生产过程中的重大危害为中毒和火灾爆炸,提出了相应的对策.     

一起甲苯爆炸事故的调查与分析

分析了利用压缩空气压送甲苯混合物时发生爆炸事故的直接原因和间接原因,提出了相应的对策.     

火电行业清洁生产评价与体会

研究并分析了火电行业清洁生产评价方法及指标体系,通过工程实例,探讨如何运用清洁生产指标体系,并对其存在的不足及评价过程中可能产生的问题,提出见解和建议。     

Warm forming die design,Part II: Parting surface temperature response characterization of a novel thermal finite element modeling code

The majority of the research activities in the area of warm forming are concentrated on demonstrating or simulating the improved formability associated with forming lightweight materials such as aluminum alloys at elevated temperatures. However, the ability to design the proper thermal management system within the forming tool is a critical aspect to delivering this technology as a viable, stable production alternative to traditional stamping. This work begins to address the thermal stability issues of this process by examining the impact of process cycle time on the parting surface temperature response. Cycle times of 10, 15, 30, and 300 s were evaluated using a reciprocating surface and a self-heated experimental block of 1020 steel fitted with resistance cartridge heaters. The presented results indicate that cycle time does not significantly impact the steady-state temperature response at the parting surface for a well-insulated die that has proper thermal management. Parting surface experimental results were compared to values obtained numerically and through the use of the novel thermal finite element analysis software PASSAGE/Forming^®.     

管式法高压聚乙烯装置的道化学火灾爆炸危险指数评价

运用道化学火灾爆炸危险指数评价方法,对Quantum管式法高压聚乙烯装置中多次出现泄漏火灾的聚合单元进行评价。对照装置实际分析了防火防爆缺陷因子,提出完善聚合单元的防火防爆措施。     

浅析硫黄生产过程中的风险与对策

分析了硫黄生产过程的危险性,并针对生产过程中高压、有毒、易燃易爆、腐蚀的特点,提出了预防措施。     

Acid generation upon thermal concentration of natural water: The critical water content and the effects of ionic composition

Thermal evaporation of a variety of simulated pore waters from the region of Yucca Mountain, Nevada, produced acidic liquids and gases during the final stages of evaporation. Several simulated pore waters were prepared and then thermally distilled in order to collect and analyze fractions of the evolved vapor. In some cases, distillates collected towards the end of the distillation were highly acidic; in other cases the pH of the distillate remained comparatively unchanged during the course of the distillation. The results suggest that the pH values of the later fractions are determined by the initial composition of the water. Acid production stems from the hydrolysis of magnesium ions, especially at near dryness. Near the end of the distillation, magnesium nitrate and magnesium chloride begin to lose water of hydration, greatly accelerating their thermal decomposition to form acid. Acid formation is promoted further when precipitated calcium carbonate is removed. Specifically, calcium chloride-rich pore waters containing moderate (10–20 ppm) levels of magnesium and nitrate and low levels of bicarbonate produced mixtures of nitric and hydrochloric acid, resulting in a precipitous drop in pH to values of 1 or lower after about 95% of the original volume was distilled. Waters with either low or moderate magnesium content coupled with high levels of bicarbonate produced slightly basic fractions (pH 7–9). If calcium was present in excess of bicarbonate, waters containing moderate levels of magnesium produced acid even in the presence of bicarbonate, due to the precipitation of calcium carbonate. Other salts such as halite and anhydrite promote the segregation of acidic vapors from residual basic solids. The concomitant release of wet acid gas has implications for the integrity of the alloys under consideration for containers at the Yucca Mountain nuclear waste repository. Condensed acid gases at very low pH, especially mixtures of nitric and hydrochloric acid, are capable of corroding even alloys, such as nickel-based Alloy 22, which are considered to be corrosion-resistant under milder conditions.     

碳酸盐对密闭空间粉尘爆炸压力影响的试验研究

为了预防和缓解工业粉尘爆炸并研究惰性粉尘对粉尘爆炸的惰化作用,在Siwek 20 L球形爆炸装置内,针对高爆镁粉和高灰分煤粉,选用碳酸钙(CaCO3)、碳酸氢钠(NaHCO3)、碳酸氢钾(KHCO3)等3种碳酸盐作为惰化剂,讨论惰化剂浓度、粒径及点火能量对最大爆炸压力的影响。结果表明,惰化剂粒径越小,浓度越高,对粉尘爆炸的惰化作用越强;粉尘爆炸的净升压与点火能量无关,点火头主要起引燃作用;当惰化剂浓度递增至60%时以上,粉尘爆炸压力急剧下降,直至不爆。此外,CaCO3的抑制效果明显优于NaHCO3、KHCO3,故推荐采用CaCO3来控制粉尘爆炸风险。     

基于心态指标的煤矿瓦斯爆炸区间数模糊评价

为了评估煤矿瓦斯爆炸的安全性,根据瓦斯爆炸的形成条件和事故致因理论,建立了评价体系。然后采用一种新的区间数模糊评价方法,建立数学模型。传统的区间数模糊评价方法是根据最大隶属度原则判断该对象的优劣,不能进行多个对象之间的评价。该方法综合考虑了最大隶属度和评语集,提出区间数的内积公式,进而得到每个对象的综合分数,通过比较其大小进行多个对象之间的评价。考虑到决策者不同心态时对决策方案的影响,引入心态指标,通过调节心态指标来比较综合分数,从而得出煤矿之间的安全性大小。最后,将该方法应用到3所煤矿,运用基于中点值的区间数排序方法对综合评判向量进行分析,所得结果与该方法的结果基本一致,从而验证该方法的正确性。