克劳斯尾气低温加氢水解催化剂研究与工业应用

Development and industrial application of the catalyzers for low-temperature hydrogenation hydrolysis of Claus tail gas

随着国家环保标准的日益严格,节能减排、清洁生产对硫磺回收尾气处理工艺和催化剂都提出了更高的要求,克劳斯尾气加氢催化剂逐渐由常规加氢催化剂转变为低温加氢催化剂。为此,重点介绍了低温加氢水解催化剂技术的研发、催化剂制备及工业应用情况。针对低温加氢过程中的SO_2加氢反应和有机硫水解反应特性,提出了加氢型催化剂和水解型催化剂组合使用的新工艺,分别研发了适合低温条件下使用的低温加氢催化剂和低温水解催化剂,将两种催化剂组合使用,使传统的加氢反应器入口温度由280℃降至220℃,同时SO_2的加氢转化率提高到超过99%。为进一步提高有机硫水解率.还开发了低温有机硫水解催化剂。实验室研究两种催化剂按体积比为5:5组合使用时尾气总硫含量(体积比)最低可达131×10^(-6)。该催化剂在15家单位的17套硫磺回收尾气处理装置上获得了工业应用,其中中国石化金陵石化分公司的尾气排放浓度低于77.9 mg/m^3,装置总硫回收率达到99,97%,应用效果良好。

With the implementation of more strict national environmental protection laws, energy conservation, emission reduction and clean production will present higher requirements for sulfur recovery tail gas processing techniques and catalyzers. As for Claus tail gas, conventional hydrogenation catalyzers are gradually being replaced by low-temperature hydrogenation catalyzers. This paper concentrates on the development of technologies for low temperature hydrogenation hydrolysis catalyzers, preparation of such catalyzers and their industrial application. In view of the specific features of SO2 hydrogenation and organic sulfur hydrolysis during lowtemperature hydrogenation, a new technical process involving joint application of hydrogenation catalyzers and hydrolysis catalyzers was proposed. In addition, low-temperature hydrogenation catalyzers and low-temperature hydrolysis catalyzers suitable for low-temperature conditions were developed. Joint application of these two kinds of catalyzers may reduce the inlet temperatures in the conventional hydrogenation reactors from 280 ℃ to 220 ℃, at the same time, hydrogenation conversion rates of SO2 can be enhanced to over 99 %. To further accelerate the hydrolysis rate of organic sulfur, the catalyzers for hydrolysis of low-temperature organic sulfur were developed. In lab tests, the volume ratio of the total sulfur content in tail gas can be as low as 131× 10^-6 when these two kinds of catalyzers were used in proportion of 5 ： 5 in volumes. Industrial application of these catalyzers was implemented in 17 sulfur recovery tail gas processing facilities of 15 companies. As a result, the Sinopec Jinling Petrochemical Co. had outstanding application performances with the tail gas discharging rate lower than 77.9 mg/ma and the total sulfur recovery of 99.97 %.