Numerical Simulation And Device Research On Hydrogen Production From Bio-methanol Reforming Of Agricult Ural Vehicles

Hydrogen energy is considered as the most potential clean zero-carbon energy in the future,which has played an important role in carbon neutrality in various fields of national economy.In order to alleviate the pollution of agricultural waste brought by China as a big agricultural country and improve the mechanization utilization of clean energy agriculture.In this paper,a bio-methanol reforming hydrogen production reactor suitable for agricultural vehicles is designed,and the reactor structure is optimized by simulation test and numerical calculation,and a flat-plate heat exchange bio-methanol reforming hydrogen production device on agricultural vehicles is created,and related experimental research is completed.The full text is summarized as follows:（1）A flat-plate bio-methanol reforming reactor was designed,and the effects of catalyst particle size,catalyst filling mode,catalyst filling amount,feed rate of bio-methanol solution,reforming temperature and molar ratio of water to alcohol on hydrogen production were studied.In this reactor,the particle size of catalyst has little influence on hydrogen production by reforming,but the filling mode and amount of catalyst have great influence on hydrogen production by reforming.When the catalyst loading amount is 20 g,and it is obliquely packed in the reforming area of the reactor,the effect of reforming hydrogen production is the best.When the feed rate of bio-methanol solution is 1.5 mL/min,the feed rate is 1500 r/min,the reforming temperature is 280℃,and the water-alcohol molar ratio of bio-methanol solution is 1.2,the hydrogen production effect of the reactor is the best.At this time,the content of H₂is 73.88%,the specific hydrogen production is 77.72 mL/g_cat.min,and the hydrogen production rate is 25.91 mL/s.（2）In order to improve the uniformity of temperature field and flow field distribution in the reactor,the numerical simulation of temperature field and flow field in the reforming area of the reactor was carried out by using fluid mechanics software.The results show that the internal structure of the reactor has obvious influence on the flow field distribution.When the interval of heat conduction ridges in the reforming area of the reactor is 40 mm and the height distribution is 5-5-5 mm from bottom to top,the flow field distribution is more uniform,which is beneficial to hydrogen production by reforming.Combined with the types and power requirements of different agricultural vehicles,a set of hydrogen production equipment for bio-methanol reforming of agricultural vehicles was designed by using this reactor.The plant mainly includes a bio-methanol reforming hydrogen production system consisting of five reactors with a total effective volume of 8.725 dm³ connected in parallel,as well as unit systems such as temperature control system,feeding system and gas purification system.（3）In order to improve the hydrogen production performance of bio-methanol solution reforming reactor,the optimization of bio-methanol reforming hydrogen production process for agricultural vehicles was carried out,and the influence rules of catalyst dosage,catalyst bed distribution,feed rate,Si C addition,reforming temperature and water-alcohol molar ratio of bio-methanol solution on hydrogen production process were put forward.The results show that when the catalyst loading is 60 g,the catalyst loading bed distribution is 1:2:3（from bottom to top）,the feed rate of bio-methanol solution is 24 mL/min,the feed rate is 1000 r/min,the Si C addition is 24 g,the reforming temperature is 250℃,and the water-alcohol molar ratio of bio-methanol solution is 1.4,the hydrogen production effect is the best.The optimum specific hydrogen production is 349.41mL/g_cat.min,the hydrogen production rate is 349.41mL/s,the H₂ content is 73.56%,the CO content is 1.12%,the CO₂ content is 23.93%,and the bio-methanol conversion rate is 89.91%.（4）In order to meet the power demand of agricultural vehicles and tractors,a multi-layer reactor parallel connection device for hydrogen production from bio-methanol reforming of agricultural vehicles was created,and the verification test was completed.The effects of catalyst bed distribution,feed rate of bio-methanol solution,reforming temperature and molar ratio of water to alcohol on hydrogen production were also explored.Based on the comprehensive parameters such as specific hydrogen production,hydrogen production rate,carbon monoxide content and conversion rate of bio-methanol,it is considered that the hydrogen production performance of the reactor is the best when the catalyst loading is 80 g,the catalyst loading bed distribution is 1:1:1:1,the feed rate of bio-methanol solution is 210mL/min,the reforming hydrogen production temperature is 250℃,and the water-alcohol molar ratio of bio-methanol solution is 1.3.The corresponding H₂ content is 74.66%,CO content is 0.84%,CO₂ content is 24.23%,the conversion rate of bio-methanol is 81.87%,the specific hydrogen production is 2175.41 mL/g_cat.min,and the hydrogen production rate is2900.54 ml/s.