Disturbance modeling and feedforwad control of flue gas denitration in coking reverse process

doi:10.11949/j.issn.0438-1157.20170216

Abstract

Abstract:

A large amount of energy is wasted in integrated desulfurization and denitration device of coking flue gas during coking reverse process. In order to solve this problem in the unique coking reverse process, causes to NO_x concentration change in the process were thoroughly analyzed. A modeling method for NO_x concentration disturbance at inlet and outlet in the reverse process was proposed by data driven identification. Verification was performed from actual data measurement on two 55-hole and 6-meter top charging coke ovens and the relationship model of NO_x concentration loss at inlet and outlet was obtained. A feedforward control system was designed for feedforward control rates of O₃ under different NO_x concentration settings. Simulation results provided cost savings of power consumption, which indicates necessity of the work.

Key words: process control, dynamic modeling, coking, reversing process, denitration

摘要：

焦化烟气脱硫脱硝一体化装置在炼焦换向过程中存在大量能源浪费，为了解决这一问题，针对焦化独有的换向过程，深入分析此过程中NO_x浓度变化的原因；提出一种利用数据驱动辨识对换向过程入口和出口NO_x浓度的扰动进行建模的方法，基于某焦化厂2座55孔6 m顶装焦炉废气的实测数据进行了验证，并得到入口、出口NO_x浓度损失的关系模型；基于所建NO_x扰动模型，针对不同的NO_x浓度设定值，设计前馈控制系统并分别求取换向过程臭氧的前馈控制率，通过仿真计算得出节省的电耗成本，表明了工作的必要性。

关键词: 过程控制, 动态建模, 焦化, 换向过程, 脱硝

CLC Number:

TP29

LI Yaning, WANG Xuelei, TAN Jie, LIU Chengbao, BAI Xiwei. Disturbance modeling and feedforwad control of flue gas denitration in coking reverse process[J]. CIESC Journal, 2017, 68(8): 3168-3176.

李亚宁, 王学雷, 谭杰, 刘承宝, 白熹微. 焦化换向过程烟气脱硝扰动建模与前馈控制[J]. 化工学报, 2017, 68(8): 3168-3176.

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