关键词: 液氨储罐, 风险评估, 技术改造

Abstract: The safety evaluation method of major hazardous source for hazardous chemicals is adopted. Through quantitative calculation, it is judged and determined that the liquid ammonia tank area belongs to the third-class major hazardous source. According to the typical accident consequences caused by leakage of liquid ammonia storage tank. A vapor cloud explosion model was established to calculate that the death radius of the vapor cloud explosion might be 4.18 m, the serious injury radius was 16.04 m, the minor injury radius was 31.19 m and the safety protection distance was 100.4 m. Then, through the establishment of the leakage diffusion model of toxic and hazardous substances, combining with the weather conditions to simulate the leakage diffusion scene. The quantitative analysis and calculation were conducted. And the conclusion was drawn that the distance from downwind poisoning was 312.01 m, the upwind poisoning was 72.01 m, and the area of the poisoning area was 16291.70 m2. On the other hand, in order to improve the essential safety level of liquid ammonia storage tank, combining with the latest safety standard and standard requirements of major hazardous source storage tank of hazardous chemicals. This paper puts forward the idea of technical transformation of liquid ammonia storage tank. Specific measures about the liquid ammonia storage tank include installation of external liquid level gauge, thermometer and pressure transmitter, adding automatic valve in gas and liquid two-phase pipeline, setting up high and low level liquid level alarm interlock device and toxic gas alarm instrument, adding automatic control start emergency spray absorption system, adding video monitoring to the storage tank area, improving measures such as weather vane, eye washer and electrostatic discharge device on the liquid ammonia storage tank etc. All of the technical transformation about the liquid ammonia storage tank was completed.

Key words: Liquid ammonia Tank, Risk assessment, technical transformation