Biomass Gas For Methanol Synthesis Process Research

In recent years, because using a lot of fossil fuel has polluted environment and because fossil fuel is in short, it is an urgent thing to look for a renewable, clean energy. Today making use of high-tech productions we can transfer biomass energy that is a style of effective and bargain price condensed solar energy into a quality energy-fuel methanol. So from the country energy sources exploitation or environment protection, it is an important and urgent topic to research biomass energy conversion. At the same time, it will bring a very important society and economy benefit to develop overall utilization biomass in our country.In this paper, gasification furnace is chose in the process of gasification at first. The result showed that fluid-bed reactor and circulate fluid-bed reactor can produce high-grade straw syngas, but the investment of the facilities is very high and the cost of production is high, it disagree with the situation of our country. The gasification process adopted the XFF-1000 downdraft fixed-bed gasification furnace in this paper, which was used in our country.The heating value of corn straw and the composition of corn straw carried on. The result showed hydrogen is only 12. 60% carbon monoxide is 15.80% and carbon dioxide is 12. 50% in the straw syngas. H/C cannot suffice the chemical reaction. The syngas contains 55. 00% (nitrogen) and 1. 4% (methane), too. Nitrogen and methane are inactive and disadvantage to synthetic reaction. The regulating H/C ways can adopt pressure-swing (getting rid of the majority of nitrogen), transformation and carbon elimination. In this paper, the regulating H/C way adopted matching hydrogen. At the same time, the straw syngas contains a spot of tar, sulphide and oxygen and so on, which result in the deactivation of copper-based catalyst. Hence, in this paper through the research of desulfurizing, dexidize, decoking etc. High-grade straw syngas obtained at last.The catalytic test of methanol synthesis for straw syngas was carried out in a tubular-flow integral and isothermal reactor. Effect of quality airspeed, pressure, temperature on synthesizing methanol were researched. C301 Cu-basedcatalyst, C302 Cu-based catalyst and NC306 Cu-based catalyst were tested, theresult showed that C301 copper-based catalyst is suitable to synthesize methanol with straw syngas than the other. Through orthogonal test and odd factor test, the catalytic techniques of raethanol synthesis from straw syngas were experimented, received preference technological parameters-space velocity 8000 L kgcat-1h-1 press 5.0 MPa temperature 235C.Deactivation of C301 copper-based catalyst is also research in this paper. Surface area and X-Ray were measured. The result showed that surface area of the spent catalyst reduced a lot than the surface area of the unspent catalyst, was down to 55%. The reduction of surface area can cause deactivation of Cu-based catalyst. In addition, the increasing of crystal of Cu can cause deactivation of Cu-based catalyst, too. There are two reasons that can cause deactivation of Cu-based catalyst. One is carbon deposited of a little of tar in the straw syngas at high temperature, the other is that a little of oxygen in the straw syngas sintered catalyst at high temperature and high pressure.