Research On The Measurement Of Biomass And Coal Blended Combustion Ratio Based On ¹³C

Biomass energy is a zero carbon emitting energy throughout its entire lifecycle and an ideal fuel for renewable energy generation.Biomass power generation mainly includes biomass direct combustion power generation and biomass mixed combustion power generation.Biomass direct combustion power generation has high costs and low efficiency.Biomass coal mixed combustion power generation can improve the efficiency of biomass power generation and effectively reduce carbon emissions from coal-fired power plants,making it the main choice for biomass power generation.The collection,transportation,and storage costs of biomass fuel are relatively high,requiring financial subsidies for biomass power generation and carbon emission reduction incentives from the carbon emission trading market to promote the development of biomass mixed combustion power generation.Both biomass power generation and carbon reduction are directly linked to biomass blended combustion.The lack of measurement methods for biomass blended combustion makes it difficult to implement the aforementioned subsidies and rewards.The development of biomass blended combustion power generation is slow,and the development of a regulatory biomass blended combustion measurement technology is of great significance.At present,most of the existing methods for measuring the biomass blending ratio are still in the theoretical stage and cannot accurately measure the biomass blending ratio.The ¹⁴C method is the only validated method that can accurately measure the biomass blending ratio.However,this method takes too long to prepare samples,has high instrument costs and complex operations,and cannot achieve online rapid measurement,making it difficult to promote and apply in industrial sites.Although there is no precedent for the application of the ¹³C method in power plants,it does not require sample preparation,has simple instrument operation and low cost,and can achieve online rapid measurement.Therefore,this article conducts research on the measurement of the proportion of coal and biomass mixed combustion biomass mixed combustion based on the ¹³C method.The ¹³C method is based on the difference in the isotope ¹³C content of coal and biomass,and quantificationally determines the blending ratio of biomass by measuring the ¹³C content of CO₂ in the flue gas from co-combustion of coal and biomass.In this paper,the ¹³C content of biomass and coal single and mixed fuels was measured using an element analyzer（EA）and an isotope ratio mass spectrometer（IRMS）in a pure oxygen environment.The error of the measurement results was within 0.02‰,demonstrating the feasibility of using ¹³C as a benchmark for measuring the biomass blending ratio.Based on the measurement results of the ¹³C content of the mixed fuel,the biomass blending ratio of the mixed fuel was calculated,and the error with the actual biomass blending ratio was within 1.5%,demonstrating the feasibility of measuring the biomass blending ratio based on ¹³C without the interference of air CO₂.Based on the ¹³C method measurement technology,a tubular furnace combustion and sampling experimental system has been designed and built,mainly including a gas supply system,a combustion system,and a flue gas sample processing and collection system.It can complete the combustion of coal and biomass,and the collection of flue gas CO₂ samples.The optimal combustion sampling conditions were determined through multiple combustion experiments.Under the optimal combustion sampling conditions,a coal biomass mixed combustion sampling measurement experiment was conducted,and the error between the experimental results and the actual results was within 1%,verifying the feasibility and effectiveness of measuring the coal biomass mixed combustion ratio based on ¹³C in a real air environment.