Experimental Study Of The Straw Biomass Slow Pyrolysis Condensate Separation

Slow pyrolysis of straw processing and comprehensive utilization is of great significance,in the process of slow pyrolysis,get the liquid product can be used is called thick wood vinegar liquid,after centrifugal separation can be divided into two layers,the upper called clear wood vinegar liquid,the lower called sedimentary wood tar.Based on the biomass energy utilization as a starting point,select biomass wood vinegar liquid and wood tar as the research object,by using such as fourier spectrometer and gas chromatography-mass spectrometry detector devices analyze the product extraction and distillation fraction,provide data of biomass liquid pyrolysis technology in chemical industry and energy.(1)Wood vinegar liquid contains a variety of compounds,such as alcohols,ketones,acids,phenols,and alkane,etc.,each component of the effect is not the same,so the wood vinegar liquid has many uses,but compared with developed countries,our country for the development and utilization of wood vinegar fluid is far,thus seriously hindered our country for the development and utilization of biomass.Wood vinegar liquid as raw materials,using three different polarity of organic solvent to extract wood vinegar liquid,and using GC/MS technology test of composition and content in the extract.The results showed that the relative of methylene chloride extraction rate is highest,about 22.2%,state that straw wood vinegar liquid has a large number of methylene chloride soluble content,polarity similar to methylene chloride.Ether and ethyl acetate of straw wood vinegar liquid and the dissolution of organic components in ability is bad,the relative extraction rate are 12.8% and 10.1%,respectively,speculated that these two kinds of the difference of the polarity of the solvent and straw wood vinegar fluid is larger.(2)Biomass wood tar with high moisture content,high oxygen content,high volatile content,the characteristics of low calorific value.But because of its water content and oxygen content are higher,and mixed some impurities,need only after the purification and modification can be used as a fuel oil.Based on the atmospheric pressure(P = 0MPa,90-180℃)and reduced pressure(P = 0.1MPa,60-180℃)two kinds of conditions distillate biomass wood tar respectively,get for light,medium,heavy three fractions and black thick wood tar,using fourier spectrometer gas phase chromatography-mass spectrometry(GC-MS)of organic compounds and their relative content in the distillate,and carries on the characteristic analysis of each fraction,corresponding compounds are summarized in the process of distillation accumulation;Combined with the separation factor of the aggregation behavior of 15 kinds of typical compounds in biological tar is analyzed.The experimental results showed that: moisture content of light,medium distillate is higher,relative content is low;Heavy fraction of moisture content is low,relative content is higher,calorific value compared with raw materials increases slightly.Acids concentration in light fraction,phenol concentration in the light and medium fractions,the light fraction is given priority to phenol class,the medium fraction is given priority to m-cresol,the heavy fraction mainly contains alkenes and alkanes material.Residues of asphalt can be used as a wood material,all of these have high industrial value.