Study On Hydrogen Production From Hydrogen Sulfide

In the 21st century, human society is faced with fossil energy depletion and environmental pollution problems. Saving energy doesn’t solve the problem, finding new energy sources is the key. Because hydrogen has wide source and high combustion value,it will be the first choice of the new energy.There are many ways to preparate hydrogen, but how to efficient and economic develop hydrogen energy still has technical problems remain to be breakthrough. Now using biomass to preparate hydrogen, and photochemical catalytic hydrogen production is the research priorities.The by-product of wet-process phosphoric acid phosphogypsum has pilled up, its utilization is only 20 to 30%:The accumulational phosphorus is not only waste the land and there are some hidden dangers, but also waste the resources, the studying of comprehensive utilization of phosphogypsum is imminent. Utilize phosphogypsum to preparate hydrogen sulfide, then use hydrogen sulfide to product hydrogen. It can keep both traditional calcium sulfate production of sulfuric acid and calcium carbonate products, at the same time add new application of calcium sulfate in the production of high value of hydrogen energy. It aimed at extending industrial chain, product the hydrogen of high additional value.Combined with the actual situation of Yunnan Yuntianhua International Chemical Co., Ltd choose fluidized bed as reactor to explore the process conditions of preparating hydrogen through the reaction between hydrogen sulfide and copper. First the paper do thermodynamic analysis of hydrogen sulphide and copper reaction, the result proves that the experiment is feasible. Then use experiment data related to physical properties of reactants system, calculating the numerical values of the parameters in the fluidized bed reactor, and get the critical fluidization velocity under different temperature and the terminal velocity,when the temperature is 700 k, the critical fluidization velocity umf=0.0039m/s, the terminal velocity ut=0.36 m/s, select operation velocity u0=0.20m/s, gas processing V=1.0 m3/h, calculated the diameter of the fluidized bed reactor dT=0.042m, according to the parameters are calculated by fluidized bed, expansion ratio R=12.5, dense phase section height in the fluidized bed reactor Lf=0.250m, height of dilute phase L1=0.366m, the reactor height in theory is 0.616m. According to the above calculation results, the actual manufacture of fluidized bed reactor size is:diameter 0.040m, height 0.600m Considering that the hydrogen and hydrogen sulfide corrosion, the main reactor materials selected 18Cr-8Ni austenitic stainless steel.Finally in the designed fluidized bed reaction device, single factor and orthogonal experiments are done. The main investigation is the effect on the conversion rate of hydrogen sulfide of copper amount, addition amount, reaction temperature, gas velocity time four factors. The experimental results show that higher temperature is to the benifit of reaction; The influence on the reaction of gas flow rate is reflected in residence time in the reactor and fluidized state. First of all, should guarantee the phase formation of fluidization state reaction in the system, and then consider the effect of residence time. Experimental results show that in the designed fluidized bed reaction device, he optimal process conditions of hydrogen preparation by sulphide hydrogen and copper in the reaction are as follows:(1) reaction temperature 600℃;(2) the gas flow rate of 4.5L/min;(3) 64 g for the amount of copper;(4) the reaction time 40min.Under the optimal process conditions, conversion rate of sulphide hydrogen is 99.21%, hydrogen yield reached 92.04%, achieved the desired goal.