Nowadays,the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China.Coal chemical looping gasification(CCLG)is a promising coal utili...Nowadays,the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China.Coal chemical looping gasification(CCLG)is a promising coal utilization technology to achieve energy conservation and emission reduction targets for highly pure synthesis gas.As a downstream product of synthesis gas,methyl methacrylate(MMA),is widely used as raw material for synthesizing polymethyl methacrylate and resin products with excellent properties.So this paper proposes a novel system integrating MMA production and CCLG(CCLG-MMA)processes aiming at"energy saving and low emission",in which the synthesis gas produced by CCLG and purified by dry methane reforming(DMR)reaction and Rectisol process reacts with ethylene for synthesizing MMA.Firstly,the reaction mechanism of CCLG is investigated by using Reactive force field(ReaxFF)MD simulation based on atomic models of char and oxygen carrier(Fe_(2)O_(3))for obtaining optimum reaction temperature of fuel reactor(FR).Secondly,the steady-state simulation of CCLG-MMA system is carried out to verify the feasibility of MMA production.The amount of CO_(2)emitted by CCLG process and DMR reaction is 0.0028(kg CO_(2))^(-1)·(kg MMA)^(-1).The total energy consumption of the CCLG-MMA system is 45521 kJ·(kg MMA)^(-1),among which the consumption of MMA production part is 25293 k(·kg MMA)^(-1).The results show that the CCLG-MMA system meets CO_(2)emission standard and has lower energy consumption compared to conventional MMA production process.Finally,one control scheme is designed to verify the stability of CCLG-MMA system.The CCLG-MMA integration strategy aims to obtain highly pure MMA from multi-scale simulation perspectives,so this is an optimal design regarding all factors influencing cleaner MMA production.展开更多
按照2012年初中国上交所发布的《上市公司2011年年度报告工作备忘录第五号——管理层讨论与分析的编制要求》,自行构建MD&A(Management Discussion and Analysis,管理层讨论与分析)信息披露质量评价指标,选取上证A股制造业220家公...按照2012年初中国上交所发布的《上市公司2011年年度报告工作备忘录第五号——管理层讨论与分析的编制要求》,自行构建MD&A(Management Discussion and Analysis,管理层讨论与分析)信息披露质量评价指标,选取上证A股制造业220家公司作为研究样本,构建回归模型,通过对2010年及2011年样本数据的搜集、整理及分析发现:MD&A信息的披露质量与当期财务绩效正相关,能够预测未来的财务绩效,并引起证券市场上公司股票的短期市场反应。展开更多
基金supported by the National Natural Science Foundation of China(21576143)Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering(2020-KF-13)。
文摘Nowadays,the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China.Coal chemical looping gasification(CCLG)is a promising coal utilization technology to achieve energy conservation and emission reduction targets for highly pure synthesis gas.As a downstream product of synthesis gas,methyl methacrylate(MMA),is widely used as raw material for synthesizing polymethyl methacrylate and resin products with excellent properties.So this paper proposes a novel system integrating MMA production and CCLG(CCLG-MMA)processes aiming at"energy saving and low emission",in which the synthesis gas produced by CCLG and purified by dry methane reforming(DMR)reaction and Rectisol process reacts with ethylene for synthesizing MMA.Firstly,the reaction mechanism of CCLG is investigated by using Reactive force field(ReaxFF)MD simulation based on atomic models of char and oxygen carrier(Fe_(2)O_(3))for obtaining optimum reaction temperature of fuel reactor(FR).Secondly,the steady-state simulation of CCLG-MMA system is carried out to verify the feasibility of MMA production.The amount of CO_(2)emitted by CCLG process and DMR reaction is 0.0028(kg CO_(2))^(-1)·(kg MMA)^(-1).The total energy consumption of the CCLG-MMA system is 45521 kJ·(kg MMA)^(-1),among which the consumption of MMA production part is 25293 k(·kg MMA)^(-1).The results show that the CCLG-MMA system meets CO_(2)emission standard and has lower energy consumption compared to conventional MMA production process.Finally,one control scheme is designed to verify the stability of CCLG-MMA system.The CCLG-MMA integration strategy aims to obtain highly pure MMA from multi-scale simulation perspectives,so this is an optimal design regarding all factors influencing cleaner MMA production.
文摘按照2012年初中国上交所发布的《上市公司2011年年度报告工作备忘录第五号——管理层讨论与分析的编制要求》,自行构建MD&A(Management Discussion and Analysis,管理层讨论与分析)信息披露质量评价指标,选取上证A股制造业220家公司作为研究样本,构建回归模型,通过对2010年及2011年样本数据的搜集、整理及分析发现:MD&A信息的披露质量与当期财务绩效正相关,能够预测未来的财务绩效,并引起证券市场上公司股票的短期市场反应。
