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.     

染料中间体废水的逆流漂洗法处理

将逆流漂洗工艺应用于4－乙酰基－2－氨基苯甲醚生产上，可使生产过程中产生的硫酸浓度为2％的硝化废水，浓缩成浓度为30％－40％的浓废酸，可供化肥厂综合利用生产硫铵肥料，从而实现生产废水零排放。实验室和生产规模试验均表明，采用该工艺后，产品的平均得率提高4．1％，产品质量的所有指标达到且超过企业标准（Q／320221NCB02－91）。     

House dust mite allergens and nitrated products:Identification and risk assessment in indoor dust

Air pollutants can potentially lead to nitration of allergic proteins, thus promoting sensitization of these allergens. However, little is currently known about the nitration status of house dust mite(HDM) allergens. We identified the occurrence of nitrated products of two major HDM allergens Der f 1 and Der p 1 in dust samples collected from college dormitories in eastern China and assessed their associated health risk. The results showed that both non-nitrated and nitrated forms of the two all...     

低铵污水灌溉下土壤中硝化作用试验研究

为模拟含低浓度铵的污水灌溉条件下土壤中硝化作用，采用了铵盐溶液(50mg/LNH4Cl)连续淋沥土壤，进行了垂向土柱试验研究，测定了土柱不同深度氮化合物的浓度。结果表明：低铵浓度污水灌溉下土壤溶液中的硝化作用主要是在30cm内发生的，NO3—N的浓度在30cm左右达到峰值。随后由于脱氮等作用，浓度迅速下降，在100cm处减小到10mg/L左右，在40cm以下土壤中未测出NH4—N。     

同步法脱氮技术可行性探讨

针对没有脱氮设施的老式污水处理场，在不增加设施的前提下，在好氧池中同时进行硝化和反硝化反应的脱氮技术进行了探讨。提出同步法脱氮的观点，对其可行性进行试验论证。     

前置反硝化技术在丙烯腈废水处理中的成功应用

根据含氰废水生物脱氮装置的运行实践分析了生物脱氮反应中废水的氨化、硝化和反硝化特点、原理。对装置进行改造后，氨氮合格率为95％以上。     

含腈污水处理

介绍了安庆丙烯腈──腈纶联合装置污水处理系统工艺路线及运行现状。含腈（氰）污水中主要污染物在生化处理过程中首先被转化为氨氮，然后进一步硝化。但在特定的水质条件下氨氮难以硝化的问题较为突出，对此进行了探讨。     

A kinetic study of phenol nitration and nitrosation with nitrous acid in the dark

We studied the transformation of phenol in the presence of nitrous acid in the dark. The main detected intermediates were 2-nitrophenol, 4-nitrophenol and 4-nitrosophenol. For the first time a kinetic analysis of the reaction in a pH interval relevant to environmental chemistry has been carried out. The kinetic data are consistent with phenol transformation being initiated by HNO₂. The results are relevant to the chemistry of the atmosphere, where HNO₂ forms upon heterogeneous conversion of ^·NO₂, and to water treatment techniques.     

焦化废水生物脱氮试验研究

采用硝化与反硝化工艺进行焦化废水生物脱氮试验,结果表明:在控制一定的工艺参数条件下,可以将500mg·L-1左右的ρ(NH3-N)降至15mg·L-1以下,COD的去除率达85%。