一种基于结构导向集总的延迟焦化动力学模型

采用22个新结构向量描述渣油分子,构建了7 004种渣油分子集总,结合模拟退火算法提出了一种模拟计算渣油分子组成的方法.制定了92条反应规则用以描述渣油延迟焦化的分子反应行为.在对工业化延迟焦化工艺进行一定程度简化和假设的基础上,建立了一个用以预测延迟焦化产物分布的结构导向集总模型.比对模型预测结果与小试试验结果发现,用建立的模型预测不同原料在不同工艺条件下的延迟焦化产物分布可靠性较好.模型计算结果表明,焦化温度上升10℃,液体收率平均提高2.5个百分点,相当于原料n(H)/n(C)提高0.15;循环比下降0.15,液体收率平均提高3.5个百分点,相当于原料残炭值下降5个百分点；反应压力下降0.03 MPa,液体收率平均提高0.6个百分点.

A delayed coking kinetic model based on structure oriented lumping concept

Based on 22 new structure vectors and 7004 kinds of molecular lumps to describe molecules as well as 92 kinds of reaction rules to describe reactions,a kinetic model for predicting product distribution of delayed coking had been built by structure oriented lumping(SOL) concept.Compared model results with experimental results,it may be seen that this model has good reliability to predict product distribution under different operating conditions of delayed coking process with different feedstocks.The effects of feedstock properties and operating conditions on product distribution had been analyzed with the proposed model.It was known from model calculation results that for the feedstock residue in this paper,liquid yield increased by 2.5 percent points on an average with temperature increase of 10℃,that was mainly equal to 0.15 H/C increase of feedstock;liquid yield increased by 3.5 percent points on an average with recycle ratio decrease of 0.15,which was mainly equal to 5 percent points carbon residue decrease of feedstock;liquid yield increased by 0.6 percent point on an average with pressure decrease of 0.03MPa.