Research On Gasification Reactions Characteristics Promoted By Ethanol-activated Biomass Char

Biomass energy,as an important component of China’s rural energy system,is not only a major driver for building an agricultural circular economy and implementing the rural revitalization strategy,but also an important engine for achieving low-carbon energy transformation.Biomass gasification technology can fully utilize dispersed agricultural and forestry waste,and has the characteristics of cleanliness,economy,and sustainability.Biomass char gasification is the main section of biomass gasification,but slow reaction rate,low efficiency,and high energy consumption limit the improvement of gasification performance.Therefore,based on the team’s previous research on chemical chain reorganization of ethanol organic waste,this paper proposes a new strategy of ethanol-activated biomass char to promote gasification reaction.This paper prepared biomass char from corn stover as raw material.Through characterization methods such as component analysis,morphology analysis,and reactivity analysis,the effect of ethanol on the characteristics and activation mechanism of biomass char was revealed.At the same time,chemical chain gasification experiments were conducted to study the chemical chain gasification performance of biomass char-ethanol solution under different conditions,and the promotion effect of ethanol on biomass char gasification reaction was verified.In the mechanism study of ethanol activation of biomass char,Fourier transform infrared spectroscopy(FT-IR)spectra indicate that at high temperatures,the introduced ethanol on one hand exacerbates the breakage of-OCH3 and C-OC bonds in the carbon chain skeleton of char,promoting char depolymerization;on the other hand,it reacts with the intermediates of char depolymerization,preventing the re-aggregation of small molecules.X-ray photoelectron spectroscopy(XPS)spectra show that introducing ethanol leads to a decrease in the proportion of C-C and C-H in char,indicating that it is conducive to the fracture of the carbon skeleton.Thermal gravimetric analysis(TG)demonstrates that introducing ethanol significantly enhances the reaction activity between char and oxygen.Scanning electron microscopy(SEM)images directly show that introducing ethanol significantly destroys the physical structure of char,enlarging the pores,thus promoting the diffusion of H2O(g)and O2 in the pores of char,improving the gasification reaction activity of biomass char,and accelerating the reaction rate.In the experimental study of chemical chain gasification of biomass charethanol solution,compared with the experimental results of biomass char-water chemical chain gasification,ethanol solution chemical chain gasification,and biomass char-ethanol solution chemical chain gasification,it was found that ethanol solution activation of biomass char promoted the gasification of char chemical chain,significantly improving the hydrogen production and carbon conversion rate of biomass char chemical chain gasification.Based on chemical chain gasification experiments with different ethanol concentrations,peroxide coefficients,and temperatures,and combined with reaction mechanism analysis,it was found that the optimal operating conditions for chain gasification were 800℃ and 0.2 peroxide coefficient.The hydrogen production enhance of 24%was achieved by driving the gasification of 0.5g char with a 10mL ethanol solution with a volume fraction of 5%.The research shows that ethanol can promote the depolymerization of biomass char during gasification,improve the reactivity of char,and facilitate hydrogen production through char gasification.This provides a theoretical basis and technical support for the efficient conversion of biomass and the clean disposal of alcohol-containing waste liquids.