天然气脱汞装置设计的思考与建议

Consideration and Suggestion on Design of Mercury Removal Equipment

天然气脱汞常采用化学吸附法,对比分析该方法中常用脱汞剂的特性、优缺点及适用范围,表明金属硫化物脱汞剂的脱汞能力更强、适用范围更广。针对天然气处理流程中脱汞装置的位置设置分析认为:采用工艺前端脱汞可以从源头降低汞所带来的危害,具有更好的应用前景;并推荐采用双塔串联吸附流程,以便充分利用脱汞剂的吸附容量;依据汞在天然气处理流程中的分布情况,提出天然气脱汞限值应以处理过程所产生的排放气和商品外输气汞含量符合相关规定为原则进行确定,参照相关规范及理论计算,天然气脱汞装置按脱汞限值28μg/m3进行设计可以满足生产要求。

Chemisorption method is usually used for removing the mercury in natural gas. The characteristics, advantages ＆ disadvantages and applicability of adsorbents used for mercury removal are compared and analyzed in this paper. The analysis shows that the metal sulfide adsorbent has stronger adsorptive capacity and wider application scope. The locations for mercury removal equipment in the natural gas treatment process were compared and analyzed. According to the result, removing mercury in the process front can reduce the harm ofmercury at source, and has better application prospect. Meanwhile, twin tower in series for adsorption is recommended, in order to make Full use of the adsorption capacity of mercury removal adsorbent. According to mercury distribution in the natural gas treatment process, the mercury limit value of natural gas should be determined by the principle that the mercury content in the exhaust gas and the commercial gas must be in accordance with the relevant regulations. Referenced with the theoretical calculation and the relevant standards, the limit value of the natural gas removal mercury equipment is designed to be 28 μg/m3 can meet the requirement of production.