Thermochemical liquefaction of pig manure: Factors influencing on oil

Abstract

This study used thermochemical liquefaction technology to prepare bio-oil from pig manure with ethanol as liquefaction solvent. The work investigated the effects of liquefaction temperatures (T), solid–liquid rates (R1) and solvent filling rates (R2) on the yield, composition and property of bio-oil. The yield of bio-oil enhanced initially and then declined slightly with the enhancement of T and R2, nevertheless, the yield of bio-oil decreased constantly with the increase of R1, and the topmost yield of bio-oil in this experiment was 35.56% when the solid–liquid rate was 5%. The work studied the properties of bio-oil generated by pig manure under different liquefaction temperatures. The results of gas chromatography–mass spectroscopy analysis revealed that the dominating composition of bio-oil from pig manure were esters, long-chain hydrocarbons, ketones, ethanol, organic acids and nitrogen compounds. The heating value of bio-oil (34.39 ~ 37.03 MJ/kg) obtained by thermochemical liquefaction of pig manure was close to the heating value of gasoline (46 MJ/kg). Electronic scanning of liquefaction residue has also been reported.