低温甲醇洗装置的扩能改造设计

REVAMPING DESIGN OF RECTISOL WASH UNIT

在总结南化大化肥现有低温甲醇洗装置实际运行状况的基础上,分析了原设计存在的欠缺以及原料结构由油调整为煤后的新工况,研究制定了扩能改造设计方案.原料改煤后,装置的设计气量将为原设计的1 .1 8倍,原料气中CO2 总量将比原设计高出30 % ,硫化物含量是原设计的4.8倍.在维持设计生产规模仍为30万t/a合成氨的基础上,增设了一个预吸收塔、一个解吸塔和部分热交换器,对部分物流的走向和处理进行了重新设计.这样的改造方案可使主要物流的技术指标均与原设计相当,单位能耗不高于原设计值,不产生新的污染源,不降低装置的操作可靠性和灵活性,可实现装置对原料油改煤的顺利转换.

On the basis of practical running conditions of Rectisol Wash Unit (RWU) in Nanjing Chemical Industrial Co. Ltd., the deficiencies in original design were summarized and the new situations in feedstock change from heavy oil to coal were analyzed. So a revamped design scheme for RWU was proposed. After the feedstock change, the raw gas flow rate,the total CO_2 and the H_2S in raw gas flow will be 1 18, 1 30 and 4 8 times as large as the original design respectively. Maintaining the 300 000 t/a ammonia synthesis capacity, a preabsorption tower, a desorption tower and some heat exchangers were added. Measures for some process flows were redesigned. The revamped design scheme could guarantee both the technique indexes of primary process flows and the energy consumption indexes were not exceed to the original design, produce no new contaminations, keep reliabilities and flexibilities for the RWU and realize a smooth transformation of feedstock change from oil to coal.