Study On Hydrogen Production From Gasification Of Landfill Leachate In Supercritical Water

With the increasing depletion of the Earth's fossil energy and the deteriorating environment,a new type of pollution-free energy as a substitute for fossil fuels is urgently needed.Hydrogen energy has attracted much attention because of its absolute pollution-free combustion characteristics,and then a variety of hydrogen production process came into being.General hydrogen production process with wasting serious or low hydrogen production rate is not large-scale promotion.While supercritical water gasification hydrogen production process because of it's fast response,high gasification rate,the process of cleaning and other advantages is gradually going into the people's vision.As a kind of environment-friendly,resource-saving new hydrogen production technology,supercritical water gasification hydrogen has excellent development prospects.The research status of leachate supercritical water gasification hydrogen production technology is discussed in this paper based on the current international supercritical water hydrogen production of the latest research results,and then the main technical problems and possible solutions to the supercritical water gasification hydrogen production was pointed out at this stage.The leachate of municipal solid waste landfill was taken as the research object in this paper,and the gasification hydrogen production is carried out in supercritical water.The effects of reaction temperature,pressure and residence time on the reaction results were discussed in detail in the leachate of municipal solid waste landfill in this paper.The effects of the volume component and yield of hydrogen,methane,carbon dioxide and the removal rate of COD and TOC in the leachate were investigated for the purpose of preparing hydrogen under different reaction conditions.The qualitative and quantitative analysis of the composition of organic matter in the filtrate liquid and the liquid product after the reaction was carried out by GC-MS.The mechanism of chemical reaction of leachate supercritical water gasification process was discussed by the use of univariate analysis and orthogonal test method.And the optimum reaction conditions for the preparation of hydrogen from the leachate in supercritical water were temperature 450 ?,pressure 27 MPa,residence time 10 min.SPSS data processing software was used to analyze the variance of the test results of orthogonal test scheme,and the significance level of each reaction condition to supercritical water gasification hydrogen production was obtained,the significant relationship from large to small is temperature> residence time > pressure.That is that the effect of temperature is the greatest,while the effect of pressure is minimal.Based on the significant relationship between the above variables and the dependent variables,the correlation of the model is better.That's that the effect of non-objective factors on the experimental results is less affected.For the correlation between the above factors,a widely used Exponential model is used to represent the yield of hydrogen in this paper.,The kinetic reaction activation energies of hydrogen and carbon dioxide were obtained by multi-parameter fitting 229-1kJ ?mol and 197-1kJ ?mol by the use of Origin and 1stOpt software,the pre-exponential factors are respectively 2.04-1S ?4.5E12-1S.And the chemical reaction kinetics model of landfill leachate supercritical hydrogen production was established according to the reaction order and constant under different temperature and pressure at last.