Structural Design And Performance Optimization Of An Alkaline Water Hydrogen Electrolyzer

Hydrogen,which is an ideal clean energy,has characteristics of no pollution,renewable,high heating value and so on.With the increase of hydrogen energy facilities represented by hydrogen fuel cells,how to obtain a large amount of pure hydrogen is one of the problems facing the development of the hydrogen energy industry.The Hydrogen production from fossil raw materials and electrolyzed water is a relatively mature hydrogen production technology that has achieved industrial operation.Although the production of hydrogen from fossil raw materials is large,it contains a lot of impurities,which will do harm to the hydrogen equipment irreversibly.The hydrogen production technology,which is an ideal hydrogen production technology and will not cause pollution,obtain hydrogen by electrolyzing water and the produced hydrogen is pure.Electrolyzed water hydrogen production technology can be divided into the pure water hydrogen production and the alkaline water hydrogen production.Their core devices are the PEM hydrogen production electrolyzer and the alkaline water production electrolyzer.The current density is the main parameter for judging the performance of the hydrogen electrolyzer.Although the existing pure water hydrogen production technology has high current density and good hydrogen production efficiency,due to the limitation of membrane electrode materials,large-scale hydrogen production cannot be achieved.The alkaline water hydrogen production technology is very mature and can realize the large-scale hydrogen production.The hydrogen production capacity can reach 1000Nm3/h.The disadvantages are low current density(about 2000A/m2-2600A/m2)and low hydrogen production efficiency.In order to increase the current density of alkaline water for hydrogen production,a new alkaline water hydrogen electrolyzer is designed in this paper.The research contents are as follows:(1)Modification of the alkaline water hydrogen electrolyzer,including the redesign of the bipolar plate size,and the use of new porous electrodes and asbestos-free membranes.(2)The designed electrolyzer is tested.By changing parameters such as voltage,current,electrolyte flow rate,and working pressure,the working data of the hydrogen-producing electrolyzer is observed to find the best working point.(3)Using the secondary current distribution,material transfer,and liquid flow models,numerical simulations of local areas inside the electrolyzer during work are performed to investigate the voltage and current distribution inside the electrolyzer.This provides suggestions for the subsequent improvement of the structure of the electrolyzer.It can be seen from the test results that the current density of the hydrogen-producing electrolyzer is increased by about 50%,and the hydrogen production efficiency is improved.The change of the test value provides a reference for the industrial operation of other hydrogen production electrolyzers.