Effect Of The Addition Of P-based Additives On Particulate Matter Emissions During The Combustion Of Biomass

As a kind of renewable energy with abundant reserves and low carbon and environmental protection,biomass can effectively alleviate the energy crisis and environmental pollution caused by the use of fossil energy.However,biomass will emit a certain amount of particulate matter during the combustion process,which will aggravate environmental pollution problems such as smog and seriously affect people's physical and mental health.In the field of coal combustion,coal-fired particulate matter emissions can be controlled to varying degrees by blending additives in fuels,and some results have been achieved.However,traditional calcium-based additives and silicon-aluminum-based additives have a more general effect on the reduction of biomass particulate matter.Compared with traditional calcium-based additives and silica-alumina-based additives,phosphorus-based additives have higher reactivity with alkali metals in biomass,react at lower temperatures to form phosphate compounds,and improve ash fusion.characteristic.However,the impact of current phosphorus-based additives on the particulate matter emission characteristics of biomass combustion processes has not been studied.In view of this,this study depends on the National Natural Science Foundation of China,“Study on the Formation Mechanism of Biomass-Formed Fuel Combustion Particles”and the National Youth Science Foundation Project“Research on Phosphorus Migration Transformation and Enrichment Control Mechanism in Phosphorus-rich Agricultural Waste Gasification Process”The effect of four phosphorus-based additives on the particulate matter emission characteristics of biomass burning process under different addition ratios,determined the optimal addition ratio of particulate matter emission reduction,and studied the introduction of phosphorus-based additives in the biomass torrefaction process.The effect of particulate matter emission characteristics during combustion.The main research contents of this paper are as follows:Firstly,a fixed bed reactor was used to investigate the effects of the addition of NH₄H₂PO₄ additives on the emission characteristics of particulate matter?PM?from corn stalk combustion.It was found that the particles produced by the burning of corn straw were bimodal and mainly composed of submicron particles?PM₁?.After adding NH₄H₂PO₄,the particles still have a bimodal distribution and mainly dominated by submicron particles?PM₁?,but the addition of NH₄H₂PO₄ can effectively reduce the emission of total particulate matter PM₁₀,especially PM₁,The emission reduction effect is closely related to the P/K molar ratio.When the P/K molar ratio is 1,PM₁ and PM₁₀ have the best emission reduction effects,reaching 44.43%and 30.70%,respectively.Secondly,In view of the low content of alkaline earth metals in cornstalks,in order to react the additives with alkali metal salts to form high-melting K-Ca/Mg phosphates,different phosphorus-based calcium salts CaHPO₄?DP??Ca?H₂PO₄?₂?CDP?and Ca₃?PO₄?₂?TCP?were studied on corn stalks at different addition ratios.The effect of combustion particulate matter emission characteristics.It was found that the particle size distribution of the particles produced by the burning of corn stalks after adding CDP,DP and TCP was still bimodal,and mainly dominated by submicron particles?PM₁?.The addition of CDP,DP and TCP all reduced the total amount of particulate matter PM₁₀,especially PM₁,to varying degrees.The CDP emission reduction effect is significantly better than ADP,DP and TCP,and when the P/K molar ratio is 1.CDP has the best emission reduction effect,with PM₁ emission reduction of 51.93% and PM₁₀ emission reduction rate of 44.09%.Finally,the effects of torrefaction on the emissions of corn stalks and the effects of adding ADP on the subsequent combustion of particulate matter during the torrefaction process were investigated.The study found that the displacement of PM₁ and PM_1-10 after corn stalk torrefaction increased differently compared with the original,and the increase rate of PM increased with the increase of torrefaction temperature.When the torrefaction temperature was 300?,the emissions of PM₁ and PM_1-10 increased by 76.52% and 183.59%,respectively.The mixing of ADP as an additive with corn stalks reduces the mass yield,energy yield and calorific value of the product to a certain extent,and reduces the yield of total particulate matter PM₁₀ produced in the subsequent combustion process,especially the submicron particulate matter PM₁ yield decreases.It is obvious.300?,the addition ratio P/K molar ratio of 1 when compared to corn stalks as it is baked,can reduce 28.81% of PM₁and 20.13% of PM₁₀.The research results in this chapter can provide theoretical guidance for the large-scale application of biomass combustion and heat generation.