Research On Process Simulation And Operation Optimization Of Coal-to-Methanol

With the commissioning of coal-to-methanol plants at home and abroad,market competition for methanol products has intensified,and companies are facing problems such as low production efficiency,backward production processes and high energy consumption.In my country,the total energy consumption of the petrochemical industry accounts for about17%of the country’s total energy consumption,ranking first among all industries.Facing new challenges,on the one hand,we should go on to develop and utilize new clear energy,on the other hand,it is imperative to vigorously implement energy conservation and emission reduction.So as to solve the problems,this paper makes a research on energy-saving and efficiency-increasing technology of coal-to-methanol plant,and proposed an optimized transformation plan for coal-to-methanol plant that uses coal gasification as the production process,which provides a reference for actual plant technical transformation.This paper takes the coal-to-methanol plant as an example,using computer simulation methods to simulate the coal pretreatment and gasification unit,the water gas shift unit,the acid gas purification unit,and the methanol synthesis unit,and optimize the use of sensitivity analysis,and use the pinch technology Used in coal-to-methanol plant.Firstly,using Aspen Plus to simulate the entire process of the coal-to-methanol plant,analyzing the material systems,and selecting the PENG-ROB physical property method as the global physical property.The process and simulation methods of the main sections are introduced in detail,the appropriate unit modules are selected,and the material balance calculation and energy balance calculation are performed to obtain 99.9%high purity methanol.Based on the simulation results,the sensitivity analysis module Sensitivity is used to analyze the energy consumption of the distillation towers and reaction units,point out the irrationality in the design parameters of each distillation tower,tap the energy-saving potential,and adjust the design of The parameters and operating parameters to reduce the energy consumption of the rectification tower.After fully optimizing the temperature and split ratio of the reaction section,the operating temperature is selected as 270°C and the split ratio is 0.7.After the tuning is completed,on this basis,the process is thermally integrated analysis,the basic logistics data is selected 13 of which are logistics,the corresponding hot and cold combination curve is drawn,and the theoretical optimal heat exchange network is filtered out by using grip technology.Finally,the new heat exchange network is designed to rematch and optimize the hot and cold logistics,which saves 55.5%of the cold utility usage and 98.6%of the heat utility usage compared to the original process..Compared with the total cost of the original process,the total cost after the transformation was reduced to 1.56×10~3million yuan/year,which achieved a considerable transformation effect.