The Engineering Design And Optimization Of Fifty Thousand Tons Of Yearly Food Grade Carbon Dioxide

In the production of ammonia, there is approximately 27% CO2 in the shift gas of decarbonization units, which can be removed by adopting low temperature methanol process. However, lacking subsequent treatment process, greenhouse effect could be intensified due to a great quantity of CO2 released, which may also against the conception of sustainable development. This project presents a complete recycling process of CO2, proposes an industrial design to produce food grade CO2, and helps achieve the objectives of the project environmentally and economically.This project, a systematic design about treatment process, aims to produce 50 thousand tons food grade CO2 annually. In the first place, the author analyzed treatment process in depth by adopting appropriate separation sequence and using Aspen Plus, which aims to carry out process simulation, determine material balance and heat balance, and complete process flow chart. In the second place, by using low temperature distillation and separation, the author has refined qualified and standard food grade CO2. During this process, sulfur and water were removed by absorption method, and non-condensable gas was removed by low temperature distillation, subsequently the food grade CO2 was condensed into a liquid.In addition, with regards to the CO2 purification tower, this paper conducted not only relevant treatment process and hydraulics design, but also sensitivity analysis towards parameters of purification tower, which helps accomplish condition design of purification tower. Moreover, based on the process design and in order to conduct systematic design, this paper determines main raw and auxiliary materials consumption, main equipment selection, technical pipeline standards and instrument flow chart. Last but not least, this project suggests that system optimization be developed and depth of system design be reached the initial level.