Experimental Study On The Production Of Bio-oils From Two Types Of Lignocellulosic Biomass Via Fast Pyrolysis

With the continuous warming of the global climate and the continuous consumption of fossil energy,people are urged to develop and utilize clean,environmental friendly and recyclable new energy to change the energy consumption mode and control the greenhouse gas emissions.The modern biomass energy has the advantages of environmental friendliness,carbon cycle,regeneration and abundant reserves.It can effectively cope with energy consumption and environmental deterioration.This paper aim at to explore the effects of acid pretreatment on the main chemical components of different biomass,and the effects of chemical component changes on the yield of biomass pyrolysis products and the properties of bio-oil.The research content includes acid pretreatment?Concentration 1%,Time 1h,Temperature 100??of woody biomass?Pinewood?and energy crop of Gramineae?Corn straw?,and a 7kg/h Auger-fed pyrolysis reactor to produce bio-oil.Through the analysis of the chemical components of different biomass materials,the characterization of the physical and chemical properties of biomass pyrolysis production and the quantitative analysis of the chemical components of bio oil by GC/MS,this research revealed the effects of acid pretreatment on the main chemical components of biomass materials,the yield and properties of biomass fast pyrolysis products?Bio-oil,Char,Non-condensable gas?.The results will provide theoretical basis for better utilization of acid pretreatment methods to improve the yield and quality of bio-oil,as well as selection and cultivation of high-quality biomass energy raw materials.The results are as follow:?1?The pinewood has lower ash content,higher lignin content.Acid pretreatment has no significant effect on C,H,O in biomass,but can significantly remove alkali and alkaline earth metal ions?AAEMs?,and the removal effect of metal ions in corn straw is more obvious.Acid pretreatment process caused decomposition of the carbohydrate polymers in the feedstocks,leaving the lignin structures of the feedstocks intact.?2?The ash content and alkali metal content are very important parameters which can greatly affect the yield of char and bio-oils produced during fast pyrolysis.The higher bio-oil yields accompanied by lower char and gas yield can be obtained with feedstocks which contain high lignin and low ash content.Acid pretreatment can significantly reduce the AAEMs content in the feedstocks,resulting in a significant increase in the bio-oil yield.?3?Acid pretreatment can increase the concentration of methane and CO in the non-condensable gas of pinewood and corn straw raw.The non-condensable gas containing high concentration of methane,CO and CO₂ can be obtained with feedstocks which contain high lignin and low ash content.?4?The low ash,high lignin and carbohydrates content in biomass feedstocks tended to cause low bio-oil water content,low total acid number,high heating value and high yield.?5?The differences of chemical components among biomass materials lead to obvious differences in the chemical components of pyrolysis oil.Phenols and Levoglucosan are the main chemical components of bio-oil.Acid pretreatment significantly reduced the ash content and AAEMs content in biomass,and effectively increased the concentration of Levoglucosan in bio-oil.Phenolic and acid compounds in pinewood bio-oil decreased,and phenolic compounds in corn straw bio-oil increased after acid pretreatment.