Abstract:

Delayed coking unit products typically mix gasoline and diesel for hydrofining, so appropriate overlap of fractions is feasible, but the overlap degree directly affects the operation and energy consumption of the unit. Based on the simulation software PRO/Ⅱ, a rigorous calculation is conducted for the entire process of the fractionation absorption and stability system of the unit. It is found that the increase of the overlap degree dose not affect the production of dry gas and wax oil. However, the amount of liquefied petroleum gas increases slightly and the total amount of gasoline and diesel decreases slightly. The heat recovery of wax oil reflux in the fractionation tower is not affected by the overlap degree, but the cooling load at the top of the tower will be partially transferred to the diesel reflux. Therefore, increasing the overlap degree is beneficial for the overall energy consumption of the unit. The absorption stable energy consumption first decreases and then increases with the increase of the overlap degree. When the overlap degree is 7.1, the energy consumption is the lowest. When the overlap degree is 11.2, the energy saving benefit is the highest, with an increase of 6.346 million yuan per year compared to the current void removal operation.

Key words: delayed coking unit, the overlap degree, simulation, exergy consumption

摘要：

延迟焦化装置产品汽柴油通常混合加氢精制，故馏分适当重叠，重叠度直接影响装置操作与用能。基于模拟软件PRO/Ⅱ,对装置分馏吸收稳定系统进行了全流程严格计算，发现重叠度增加基本不影响干气和蜡油产量，但液化石油气量小幅增加，汽柴油总量小幅下降；分馏塔中蜡油回流取热不受影响，但塔顶冷却负荷会部分转移到柴油回流，因此提高重叠度对装置用能总体有利；㶲耗随重叠度增加先降后升，重叠度为7.1时，㶲耗最低，重叠度为11.2时，节能效益最大，较当前脱空操作增效634.6万元/a。

关键词: 延迟焦化装置, 重叠度, 模拟, (火用)耗