浅冷油吸收法在炼厂混合干气回收中的应用

Application of shallow cold oil absorption technology in recovery of refinery dry gas

采用浅冷油吸收工艺对国内某炼厂副产催化干气和焦化干气中的碳二及以上馏分进行回收,根据对饱和干气和不饱和干气的处理方式不同,制定了2种回收方案,方案一为设置2套碳四吸收-解吸系统分别处理饱和干气和不饱和干气,方案二为设置1套碳四吸收-解吸系统来统一处理饱和干气和不饱和干气的混合气。利用流程模拟软件Symmetry对上述2种方案进行模拟计算,结果表明,2种方案均可达到回收碳二提浓气的要求,其中,方案一将饱和干气和不饱和干气分开处理,回收率高,适用性强;方案二的产品纯度较方案一高,但能耗较大。

The shallow cold oil absorption process is employed to recover C+ fractions from the by-product catalytic cracking dry gas and coking dry gas of a certain refinery.According to different treatment methods for saturated dry gas and unsaturated dry gas, two corresponding recovery schemes are formulated.In scheme I,two sets of Cabsorption-desorption system are set up to process saturated dry gas and unsaturated dry gas respectively;In scheme Ⅱ,a set of C4 absorption desorption system is established to uniformly process the mixture of saturated dry gas and unsaturated dry gas.Simulation results obtained by Symmetry software reveal that both schemes can meet the requirements of recovering carbon dioxide concentrated gas.The scheme I gives a high recovery, low energy consumption and strong adaptability, which processes the saturated dry gas and unsaturated dry gas separately.By scheme Ⅱ,the product has a higher purity, but the energy consumption is larger.