摘要
用磷化氢尾气制备超纯磷的生产过程中,涉及磷化氢、砷化氢和磷等易燃易爆或有毒物质,易引起泄漏、中毒和爆炸事故,需对其进行风险评价。对设计的磷化氢生产超纯磷工艺过程的主要部件进行了HAZOP定性分析,得出控制风险的关键是压力安全保护系统、密封系统、废气排放控制、原料气成分控制和制冷剂充灌量控制。用重气扩散理论模型对高压磷化氢储罐进行了定量分析,得出危险发生时需疏散人员至8 km以外。最后研究了整个系统各个部分的主要安全隐患和应采取的安全保护措施,研究结果对该生产设备和工艺过程安全保障有重要帮助。
The present paper takes as its target to introduce an improved risk assessment method in producing ultra-pure phosphorus by using phosphine vented from the industry by using the vented gas gained from the production of sodium hypophosphite. It is known that ultra-pure phosphorus is a kind of original craftwork for energy-saving and environmental protection and vented gas is a mixture made of phosphine, arsine, hydrogen, carbon dioxide, oxygen, methane, etc., which are inflammable and explosive, therefore, involving a certain potential risk. What is more important is that phosphine （at a concentration of more than 50% ）, arsine and the production phosphorus（5N）, are all highly poisonous, which can be thought of as the prime carrier of poisonous leakage, leading to explosion. At the beginning of our craftwork, we had adopted cryogenic and adsorbent method of purification to turn the vented gas into highly concentrated phosphine. But, then, with the phosphine being input at the speed of 800 m^3/h, the catalyst in the rector is likely to get blown suspended so as to make the phosphine decomposed into phosphorus and hydrogen. And, now, the installation producing ultra-pure phosphorus, known as catalytic reactor and the ventilator, would work at high temperature of 500 ℃ and high pressure of 0.8 MPa. The ventilator would make the gas of phosphine decompose at a rate of 95 %, which tends to be the most dangerous piece of installation. It is just for reducing the risk likely to be caused by using this critical piece of installation that we have chosen the so-called HAZOP method to conduct the qualitative analysis. Practically speaking, what we have done is to analyze the temperature, by using the head words ＂more ＋ less ＋ other than＂ to the pressure, as well as the flow and change of the input phosphine ： In doing so, we have also used the dense gas diffusing model in analyzing the tank＇ s high pressure in which the highest concentration of phosphine would crop up with 2 m^3 of phosphine at 0.8 MPa. Here, it was concluded that once leaked, safe place can only be found in a distance of 8 km away. Besides, some kinds of absorbents and active carbonates should be prepared with a 30-meters＇ ventilation pipe. In addition, some other safety insurance measures should he taken to protect the entire installation system to enhance the control. Hence, the risk assessment of the original craftwork can help to promote the optimal safety production.
出处
《安全与环境学报》
CAS
CSCD
2008年第4期160-163,共4页
Journal of Safety and Environment
关键词
环境工程
磷化氢
超纯磷
毒性
风险评价
environmental engineering
phosphine
ultra-pure phosphorus
toxicity
risk assessment
