Study On The Molding And Surface Carbonization Of Rice Straw And Cow Manure

Aiming at the problem that biomass seedling pot has poor ability to maintain seedling type in warm and humid environment without adding any binder,rice straw and fermented cow manure are used as raw materials,and biomass molding and surface carbonization technology are used to study an environmentally friendly biomass seedling pot that can meet the requirements of planting technology.Through the method of theoretical analysis and experimental research,the systematic research was carried out from the theory of compression molding of biomass seedling pot,compression molding test of seedling pot,surface carbonization test of seedling pot,seedling test and other aspects.The main research contents and conclusions are as follows:(1)Research on the theory of compression molding of biomass seedling bowl: analyze the principle of compression molding of biomass materials,and obtain its physical and chemical properties and molding characteristics;Analyze the mechanical properties in the process of biomass compression molding,and establish the mechanical model of biomass compression molding process.Analyze the biomass molding process and determine the carbonization molding process after molding;The main influencing factors of biomass molding quality were analyzed,and the test factors of compression molding of seedling bowls were determined.(2)Experimental research on compression molding of seedling bowl: rice straw and fermented cow dung are used as test raw materials;forming pressure,forming temperature,straw content and moisture content of raw material are selected as test factors,and durability,compressive strength and dimensional stability are taken as indicators.Single-factor and Box-Benhen Design(BBD)design methods were used to explore the influence of each factor on the durability,damage resistance and dimensional stability.The test results show that the best process parameters of compression forming of the seedling bowl are the forming pressure is 160 k N,the forming temperature is 134℃,the straw content is 8%,and the water content of the raw material is 16%.Under this condition,the durability of the seedling bowl is 99.736%,the compressive strength is 4.416 MPa,and the dimensional stability is 98.025%.(3)Experimental study on the carbonization treatment of the surface layer of the seedling bowl: the seedling bowl prepared with the optimal process parameters is used as raw material;The carbonization temperature and carbonization time were selected as test factors,and the durability and swelling rate were used as indicators.The influence of each factor on the durability and swelling rate of seedling bowls was explored by using single factor and Central Composite Design(CCD)design methods.The test results show that the best process parameters for the carbonization treatment of the surface layer of the seedling bowl are carbonization temperature of 1010 °C and carbonization time of 25 s,and the durability is 97.671% and the wetting rate is 7.013%.(4)Pot seedling rearing test: In the tomato seedling rearing test,the pot body without surface charring treatment cracked and melted,while the pot body was intact after surface charring treatment.The plant height,stem diameter,number of leaves,root-shoot ratio and seedling strength index of seedling pot treated with surface char were 187.17 mm,3.48 mm,5.70 pieces,0.0929 and 0.0454,respectively.The parameters of tomato seedlings in plastic rearing pot for 30 d were 181.67 mm,3.40 mm,5.30 pieces,0.0859 and 0.0439,respectively.Without surface carbonization treatment,the parameters of the seedling bowl tomato seedlings for 30 d were175.17 mm,3.15 mm,4.30 pieces,0.0791 and 0.0412,respectively.The results showed that the surface carbonized seedling pot could replace the plastic seedling pot.