Studies On Process Simulation And Experiment Of Acid Removal From Natural Gas By Amine Method

The development of the LNG industry technology reflect irresistible trend due to the natural gas demand growth constantly. However, natural gas contains some acid gas, such as carbon dioxide and hydrogen sulfide. Before the liquefaction process, the acid gas should be deeply removed to guarantee the stable operation of the liquefaction device. At present, there is no systematic technology focusing on the natural gas acid removal. Most of the experiments choose the non-column devices like flasks or reaction stills. While the experimental process is discontinuous with a lower fit rate of actual producing. Therefore, it is crucial to do experimental research by using devices which can simulate the actual process of amine solvent acid removal in the factories under various process conditions.In this essay, design calculation, simulation and experiment is mainly applied to built a device which can fufill experiment of amine solvent acid removal line with actual factories, and complete the research of core process technologies of acid removal by amine method. Firstly, according to the results of literature review, the traditional procedures of amine solvent acid removal have been improved, and the model of the critical equipment of the process, absorption tower, regeneration tower, heat exchanger, separator and reboiler, are selected, and the key process parameters have been determined. Secondly, The simulation analysis of the process has been accomplished. Device functions and rationality about all designed parameters have been proved by simulation, at the same time the adaptability and energy consumption of the devices under different acid concentrations have been tested. In addition, the mixed amine TEA+MEA and MDEA+MEA have been researched under different gas materials conditions. The effects of different acid removal process have been analyzed. Moreover, by changing the parameters about absorption and regeneration, the impact rules of each element on performance and energy consumption are investigated to determine the best parameters.Based on the research mentioned above, a set of removing acid gas by amine experimental devices have been built with the purification rate H2 S < 4ppm and CO2 < 50 ppm. The device can implement the acid removal under various process like single(double) absorption tower. The best process parameters of mixed amine TEA+MEA and MDEA+MEA have been analyzed through experiment. Meanwhile, the results of experiment show the changing rules that effect absorption and regeneration performance. The results of the study can provide the theory guide and reference for the LNG factories engineering design and absorbent selection.