Reforming Utilization Of Carbon Emissions From Coal To Olefins And Hydrogen-rich Dry Gas In Refineries And Its Evaluation

At present,environmental issues have become a topic of common concern to all mankind.China is in a period of rapid economic development,the high carbon emissions and other energy environmental problems issue caused by the booming economic development are gradually being paid attention to.The special energy structure of‘rich in coal,low in oil and poor in gas’ means that coal needs to be the focus of energy utilization.A disadvantage of coal chemical process is that it will produce higher carbon emissions,and as the main representative of coal chemical process,the coal to olefin process will inevitably suffer great pressure to reduce emissions.From the perspective of the enterprise,in order to reduce carbon emissions,making a large-scale transformation of the existing processes is not realistic,but converting carbon dioxide into a high value-added product can alleviate the pressure of carbon emissions reduction while increasing enterprise’ s benefits.The main reason for the high carbon emissions of the coal to olefins process is that raw gas must be adjusted by the water gas shift reaction to meet the subsequent synthesis requirements,while a large amount of carbon dioxide will be emitted during the adjustment of the components.In order to study the low-carbon development route of the coal to olefins process,a CTO plant in Baotou City,Inner Mongolia Autonomous Region of China,built by Shenhua Group,was selected as the reference target in this paper.This paper proposes an integrated hydrogen-rich refinery gas assisted coal to olefins process(G-CTO),which includes the tri-reforming unit.After that,the Aspen Plus software is used to simulate each unit of the new process.The technical and economic analysis of the results obtained by the simulation is carried out to find out the advantages and disadvantages of the new process,and to provide a theoretical reference for the optimization and transformation of the process in the coal chemical industry in the future.By simulating the G-CTO process proposed in this paper,compared to conventional coal to olefins process,we find out that the CO2 emissions per ton olefins product of G-CTO is decreases by 34%.And technical and economic analysis shows that energy efficiency is increase by 10.5%and the production cost for G-CTO is 14.8%higher than that of coal to olefins process.Although the production cost of the G-CTO process has increased,considering the strict carbon emissions requirements in the future,the new process still has a large potential advantage.