Case study on the catastrophic explosion of a chemical plant for production of m-phenylenediamine

On March 21, in Xiangshui County, Yancheng city, China, a catastrophic explosion occurred at Tianjiayi Chemical Co., Ltd. that caused 78 deaths and injured more than 617 individuals, with a property loss of as much as US$ 100 million. An explosion crater with a diameter of 98 m was generated. An extensive consequence analysis based on the crater size and physical effects for the estimation of the quantity of exploded dinitrobenzene (DNB) was performed. By using the position recorded in the satellite photo and the layout of the plant, the crater site was determined to be located near a warehouse where dinitrobenzene was stored. From the scaling law associating the TNT equivalent with crater diameter, the TNT equivalent of exploded ditrobenzene was determined to be approximately 708 tons. Based on the results of the consequence analysis performed by three methodologies, it can be concluded that the Tianjiayi Chemical Co. warehouse not only stored a substantially large quantity of dinitrobenzene but was also located too close to adjacent structures without an adequate separation distance. Judging by the effect of explosive blast on personnel, a fatality radius was determined to be about 400 m from the explosion center.     

Hazard analysis on LPG fireball of road tanker BLEVE based on CFD simulation

In order to research the hydrocarbon fireball characteristic of LPG tanker Boiled Liquid Evaporate Vapor Explosion (BLEVE) under different conditions, computational fluid dynamics (CFD) simulations of the hydrocarbon fireballs from the LPG tanker BLEVE accidents were carried out. Several new different factors, such as the mass of fuel, inlet velocity and airflow velocity, were considered to analyze the influence on the evolution of the characteristics of the fireball and the development of the LPG tanker BLEVE accidents. Results indicate that the fireball with a greater mass of fuel radiates more heat but slower. The large longitudinal diameter of the fireball and high radiation heat flux are observed in case of a faster inlet velocity used for the same mass. The airflow was found to shorten the initial phase of the fireball effectively. Some suggestions were proposed to prevent the LPG BLEVE accidents. Analysis performed show that various parameters like fireball diameter, radiative heat flux and lifting speed of fireball can be predicted well using FDS code.     

危化品泄漏围堵材料理化性能及燃烧行为研究

针对易燃液体泄漏围堵问题,开发了1种可快速发泡的酚醛泡沫材料,对其表观密度、耐水性、耐酸性、耐碱性、氧指数、燃烧行为及产烟成分进行系统研究。研究结果表明:发泡材料在中性和酸性液体环境中表现出良好的耐受性;在碱性环境中稳定性降低,由于共轭效应,导致分子中的H+遇碱性环境发生中和反应;发泡材料的氧指数和锥形量热测试参数（热释放速率、总热释放量及总生烟量等）表明该材料具有良好的耐火性;发泡原料中的含硫交联剂是其燃烧产烟生成较高浓度SO2的主要原因。     

危险化学品分类体系现状及在海洋环境应急监测中的应用

综述了国内外危险化学品分类体系,以苯乙烯为例,参考欧盟SEBC体系,建立了危险化学品海洋环境应急监测信息卡,内容包括分类、索引号及纳入名录,理化性质及行为特征判断,健康危害及防护要求,检测方法及评价标准等4类信息。建议进一步筛选海洋污染事故涉及的典型或高危化学品,细化SEBC体系,加强快速检测技术研究,构建适应我国海洋环境应急监测需求的危险化学品分类体系和数据库。     

动电修复不同形态重金属污染土壤效果研究

以钢铁厂附近废地的重金属土壤为对象,研究了动电修复技术去除重金属效果与其各化学形态的关系,讨论了电能消耗。结果表明,同一种重金属,其动电去除效率顺序为交换态碳酸盐结合态Fe-Mn氧化结合态有机结合态残留态,即吸附性越弱的形态,其去除率越高,如交换态去除率95%;吸附性越强的形态,其去除率越低,如有机态和残留态去除率低于29%;对于不同重金属,高移动性和弱吸附性的重金属较弱移动性和强吸附性的重金属去除效果好,即各形态的Cd、Cu和Zn的去除率明显高于相应形态Pb的去除率;能耗分析表明,实验时间超过96 h后,在电能有较大消耗的同时,重金属去除率却提高不明显。     

Molecular diversity of arbuscular mycorrhizal fungi in relation to soil chemical properties and heavy metal contamination

Abundance and diversity of arbuscular mycorrhizal fungi (AMF) associated with dominant plant species were studied along a transect from highly lead (Pb) and zinc (Zn) polluted to non-polluted soil at the Anguran open pit mine in Iran. Using an established primer set for AMF in the internal transcribed spacer (ITS) region of rDNA, nine different AMF sequence types were distinguished after phylogenetic analyses, showing remarkable differences in their distribution patterns along the transect. With decreasing Pb and Zn concentration, the number of AMF sequence types increased, however one sequence type was only found in the highly contaminated area. Multivariate statistical analysis revealed that further factors than HM soil concentration affect the AMF community at contaminated sites. Specifically, the soils’ calcium carbonate equivalent and available P proved to be of importance, which illustrates that field studies on AMF distribution should also consider important environmental factors and their possible interactions.     

Potential Methods for Managing Prymnesium parvum Blooms and Toxicity,With Emphasis on Clay and Barley Straw: A Review1

Hagström, Johannes A., Mario R. Sengco, and Tracy A. Villareal, 2010. Potential Methods for Managing Prymnesium parvum Blooms and Toxicity, With Emphasis on Clay and Barley Straw: A Review. Journal of the American Water Resources Association (JAWRA) 46(1):187-198. DOI: 10.1111/j.1752-1688.2009.00402.x Abstract: Harmful algal bloom (HAB) control and mitigation is a complex problem in ecosystem management. Phytoplankton play an important role in aquatic ecosystems as primary producers and food sources for many commercially important shellfish and there are limited options for targeting just a single species within the community. Chemical treatments (e.g., algaecides), rotting barley straw, nitrogen and phosphorus manipulation, and clay and/or flocculants are but a few techniques tested or used to reduce fish kills or shellfish contamination during a HAB event. Prymnesium parvum control has focused on the use of chemicals, nutrient manipulation, and clay flocculation. However, many HAB control methods have been rejected due to their effects on ecosystems, high costs, or limited effects on target organisms. For example, rotting barley straw (Hordeum vulgare) is considered to be an environmentally friendly alternative, but has been found to have very different results on the phytoplankton community depending on the dominating taxa and is ineffective against P. parvum and dinoflagellate blooms. Clay flocculation is a useful control/mitigation technique during fish kills in marine aquaculture sites in South Korea and can be effective in freshwater if the correct combination of clay and flocculent is used. Toxins produced by P. parvum and Karenia brevis also bind to phosphatic clay, thereby removing and/or neutralizing the toxins, but there is concern that the clay will have a negative effect on sessile organisms. Some shellfish suffer high mortalities and significant impacts on somatic and reproductive tissue growth at high clay loads; however, benthic communities appear to be unchanged after five years of clay treatment in South Korea. There are likely site-specific and ecosystem-specific characteristics that make generalizations about control options difficult and require careful assessment of options at each location.     

植物化学杀雄研究进展

介绍了化学杀雄剂诱导植物雄性不育的变化,回顾了化学杀雄杂种优势利用研究的进展,阐述了化学杀雄杂种优势利用的特点,以及化学杀雄剂的设计思路和常用的化学杀雄剂。     

声屏障在化工行业的应用

化工行业噪声源多,声级高,防火、防爆、防腐、防风险等要求特别严格。采用常规噪声控制措施受到许多限制,而采用隔声吸声屏障降噪有一定效果。本文以上海几个化工企业为例,论述了隔声吸声屏障的设计、应用及效果。     

2013年长江丰水期河水化学特征及控制因素

为掌握长江河水化学组成特征及其控制因素,笔者运用Gibbs图、多种离子比例系数法和主成分分析法综合分析了长江流域丰水期河水化学及氢氧同位素特征。结果表明,长江丰水期河水主要来源为大气降水,河水化学类型主要为HCO₃·SO₄-Ca型,化学成分主要受流域内广泛分布的碳酸盐岩等岩石风化作用控制;河水pH值、HCO₃^-浓度沿长江径流方向降低,SO₄^2-、Ca²⁺浓度沿长江径流方向升高。2013年丰水期,长江河水化学组成特征变化的主要影响因子,是易溶盐岩溶解和人类活动(贡献率40%),其次为川贵及长江三角洲地区的酸雨沉降以及人为酸性废水排放促进了流域内石灰岩和富含碳酸盐的三叠系砂页岩溶解(贡献率20%),最后为硅酸盐矿物及其风化产物的溶解(贡献率19%)。为了解长江河水水质状况及其演变趋势,合理评价长江流域水资源提供很好的科学依据。