Performance Investigation Of Autoswitch Hydrogen Absorption & Desorption Cycle Program

Over the past decades,metal hydride reactor has been greatly improved and promoted as an important place for reaction in hydrogen development and utilization.Unfortunately,owing to the different operation conditions,most metal hydride reactors could not realise the autoswitch between hydrogenation&dehydrogenation and the free cycle without the help of extra factor,which could cause many inconveniences and safety problems to the H2 absorption&desorption cycle,especially for the ocassions with high frequency and intensity.Hence we proposed two programs based on the structure improvement and PLC to realize the proper open and close of each channel and the stable coordination among valves automatically.The numerical simulation for H2 absorption/desorption using LaNis was accomplished,and the optimizations on both structure and operation conditions were achieved within a certain period of cycle time.Furthermore,the metal hydride H2 compression system with the absorption&desorption cycle has been investigated.The results are as below:(1)The relationship among operating temperature,H2 pressure and reaction finish time during absorption/desorption process was investigated and simulation data were also fitted to obtain integration equations with Matlab to provide the mathematic basis for the structural optimization in the future.(2)Under the hydrogenation/dehydrogenation conditions of 3MPa(20 ?)/0.1 MPa(80 ?),the simulation results indicate the optimal initial reacted fraction and total cycle time are 0.07 and 1287s,respectively.(3)Both structure parameters of autoswitch device with 4 and 6 openings have been obtained under the optimal conditions.(4)H2 compression system could get pure H2 of 2.276MPa/12.24MPa after 8 cycles under the heating condition of 90?/200? and the tank volume of 500ml;The H2 pressure of the MHTC could reach 12.24MPa,9.72MPa and 8.08MPa respectively with the tank volume of 500ml,1000ml and 1500ml at 200?;The solution with preheating before dehydrogenation is superior to the one without preheating at 200?,and the final pressure is 12.24MPa and 15.32MPa respectively.The two autoswitch H2 absorption&desorption programs can realize the automatic switch between hydrogenation and dehydrogenation orderly and controllably,which would provide convenience for the occasions with this demand and show its remarkable value during popularization and application.