Microscopic mechanism study and process optimization of dimethyl carbonate production coupled biomass chemical looping gasification system  

作　　者：Wende Tian Jiawei Zhang Zhe Cui Haoran Zhang Bin Liu 

机构地区：[1]College of Chemical Engineering,Qingdao University of Science&Technology,Qingdao 266042,China

出　　处：《Chinese Journal of Chemical Engineering》2023年第6期291-305,共15页中国化学工程学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(22178189);the Natural Science Foundation of Shandong Province(ZR2021MB113);the Postdoctoral Science Foundation of China(2022M711746)。

摘　　要：Biomass chemical looping gasification technology is one of the essential ways to utilize abundant biomass resources.At the same time,dimethyl carbonate can replace phosgene as an environmentfriendly organic material for the synthesis of polycarbonate.In this paper,a novel system coupling biomass chemical looping gasification with dimethyl carbonate synthesis with methanol as an intermediate is designed through microscopic mechanism analysis and process optimization.Firstly,reactive force field molecular dynamics simulation is performed to explore the reaction mechanism of biomass chemical looping gasification to determine the optimal gasification temperature range.Secondly,steady-state simulations of the process based on molecular dynamics simulation results are carried out to investigate the effects of temperature,steam to biomass ratio,and oxygen carrier to biomass ratio on the syngas yield and compositions.In addition,the main energy indicators of biomass chemical looping gasification process including lower heating value and cold gas efficiency are analyzed based on the above optimum parameters.Then,two synthesis stages are simulated and optimized with the following results obtained:the optimal temperature and pressure of methanol synthesis stage are 150℃ and 4 MPa;the optimal temperature and pressure of dimethyl carbonate synthesis stage are 140℃ and 0.3 MPa.Finally,the pre-separation-extraction-decantation process separates the mixture of dimethyl carbonate and methanol generated in the synthesis stage with 99.11%purity of dimethyl carbonate.Above results verify the feasibility of producing dimethyl carbonate from the perspective of multi-scale simulation and realize the multi-level utilization of biomass resources.

关 键 词：Biomass chemical looping gasification Reactive force field molecular dynamics simulation SEPARATION Multi-scale simulation 

分 类 号：TQ225.24[化学工程—有机化工]