| In this thesis,the compressibility of the mixture of corn stalk and lignite is studied through the designed compression device,and the main factors that affect the drop strength and combustion calorific value of the briquette after the “open type” compression of the mixture of corn stalk and lignite are studied.The biomass content,compression section diameter,and compression speed have been experimentally studied and analyzed.The optimal compression factor level of the mixture of corn stalk and lignite under different test conditions was found to provide a reference for actual production.(1)Through single-factor experimental research and analysis,a compression model of bulk modulus K and compression is established,and the effects of biomass content,forming cross-section diameter and compression speed on the compressibility of cold pressing of the mixture of corn stalk and lignite are analyzed.influences.It is concluded that the larger the corn stalk content,the smaller the compression speed,the better the compressibility,and the best compressibility is when the diameter of the forming section is15 mm.The compressibility of the mixture of corn stover and lignite was obtained.Through experimental research and analysis of a single factor,a compression model of bulk modulus K and compression is established,and the influence of biomass content,forming cross-section diameter and compression speed on the compressibility of the mixture of corn stalk and lignite is analyzed.It is concluded that the higher the corn stalk content,the lower the compression speed,the better the compressibility,and the best compressibility is when the diameter of the forming section is 15 mm.(2)Obtained the law of the falling strength of briquette after cold pressing of the mixture of corn stalk and lignite.Through the study and analysis of the drop strength of the briquette,the influence of various factors on the drop strength of the briquette is as follows:when the corn stalk content is between 10% and 25%,with the increase of the corn stalk content in the briquette,the briquette The strength of the drop increases.When the corn stalk content is 25% and 30%,the drop strength changes tend to be stable;the compression speed is within the range of 10mm/min and 25mm/min,the briquette drop strength becomes larger and changes drastically as the compression speed increases.The compression speed at 25mm/min,40mm/min and 55mm/min drop strength changes tend to be stable,indicating that the impact of the drop strength is very small within this range;when the cross-section diameter is 15 mm,the maximum drop strength of briquettes is96.2%.The law of the falling strength of briquette after cold pressing of the mixture of corn stalk and lignite was obtained.Through the study and analysis of the drop strength of briquette,the influence of each factor level on the drop strength of briquette is as follows:when the corn stalk content is between 10% and 25%,the drop strength of briquette increases with the corn stalk content in the briquette and increase.However,when the corn stalk content is 25% and 30%,the drop strength changes tend to be stable;when the compression speed changes within the range of 10mm/min and 25mm/min,the drop strength of the biomass briquette increases with the increase of the compression speed And the changes are drastic.The compression speed at 25mm/min,40mm/min and 55mm/min drop strength changes tend to be stable,indicating that the impact of the drop strength is very small within this range;when the cross-section diameter is 15 mm,the maximum drop strength of briquettes is 96.2%.(3)Obtained the law of the combustion calorific value of briquette after cold pressing of the mixture of corn stalk and lignite.The calorific value of briquette between 10% and30% of the corn stalk content gradually decreases with the increase of the corn stalk content.When the corn stalk content is 30%,the combustion calorific value is at least21867.2k J/kg,and the corn stalk content is 10 %,the maximum combustion heat value is23324.3k J/kg,but the diameter of the forming section and the compression speed have little effect on the combustion heat value of the biomass briquette.(4)By using Design Expert to analyze the quadratic response surface test,the regression equation of each factor level on the falling strength of the biomass briquette after forming is obtained: By using Design Expert software to analyze the quadratic response surface test,obtained The regression equation of each factor level on the briquette strength,and The regression equation of each factor level to the combustion heat value is obtained.The degree of influence of each factor level on the drop strength is obtained in the order: A(content of corn stalk)> C(speed of compression)> B(diameter of forming section);and the influence of each factor level on the heat of combustion value The order of influence degree is: A(content of corn stalk)> B(diameter of forming section)> C(speed of compression).(5)By optimizing the parameters of the regression equation,the optimal factor level for the cold-pressed "open type" compression molding of the mixture of corn stalk and lignite is obtained: the biomass content is 26.89%,the cross-section diameter of the molding is 16.64 mm and the compression speed is 36.94mm/ min,the drop strength is95.6%,and the heat of combustion is 23624.4k J/kg.Experimental verification can show that the results of parameter optimization are reliable,and through the use of quadratic response surface experiments,the regression equations obtained can be used to select factor levels in actual production.Through optimization of parameters,the optimal factor level for cold-pressing "open type" compression molding of a mixture of corn stalk and lignite is obtained: biomass content is 26.89%,forming cross-section diameter is 15.00 mm,and compression speed is36.94mm/min.Its heat of combustion is 23624.4k J/kg,and its drop strength is 95.6%.At the same time,the experimental verification shows that the result of parameter optimization is reliable. |
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