Experimental Study On The Production Technology And Performance Of Degradable Bagasse Mulch

Mulch is used widely in china,by covering mulch,the temperature and moisture of soil can be preserved,loss of water and nurishment can be decreased,which lead to yield-raise.However,plasticmulch residue is serious,it causes a series of problems.Moisture and fertilizer flow blocked,the bulk density of land increases,soil compactioned,lead to a serious decline in the quality of cultivated land.Every year there are a large number of crop straw abandoned in our country,give rise to environmental pollution,as an example crop stalks burning enhanced the air pollution,soil activity reduce.Utilization of a degradable mulch produced from crop stalks replace the plastic mulch.It can solve the problem of residues of crop straw,enhance the added value of agricultural production,solve the problem of plastic mulch residue and improve the quality of agricultural cultivated land.The paper studied preparation techonology of bagasse pulp and mulch.The following experimental study was studied:(1)According to the characteristics of bagasse and no pollution to the farmland,the mechanical beating,the high-temperature and steaming,chemical mechanical pulping was used for bagasse fiber pretreatment.Because bagasse fiber is short,chemical mechanical pulping was the best pretreatment method.(2)The effects of different concentrations of NaOH on the components of bagasse(cellulose,holocellulose and lignin)were analyzed to determine the experimental level.The bagasse was digested with different NaOH concentration,the components of bagasse after cooking were measured,and the trend of each component was analyzed.The physical and chemical characteristics of bagasse with different concentrations of naoh high temperature vacuum cooking were analyzed.physical properties of bagasse fiber include microstructure,thermalpropertiesandgeometry;Chemicalcharacteristicisthechangeof cellulose,holocellulose and lignin content.(3)Using different concentration of NaOH for single factor test,steam cooking was carried out,pulp beating and handsheet.The determination of the mechanical properties are tensile strength,burst index,folding resistance and tear index.Establishment the mechanical model,the significance of each factor,response surface analysis and the factors that affect to the mechanical properties were analyzed.The optimal combination parameters are NaOH concentration 9.20%,beating time 13mins,corresponding tensile strength 37.64N/m,burst index 1.52kPa·m~2/g,folding endurance 40 times,tear index 39.21mN·m~2/g,the credibility of optimization result is 0.927.(4)Bagasse mulch field performance includes the water retention,that has a high water retention capacity to provide adequate water for crop growth.The composition of the sizing agent on the surface of the mulching was determined by the test,and the water retention performance of the film under different sizing conditions was measured.The significance of the factors was analyzed by the response surface analysis.The optimum water repellent performance are 46.16%of sodium silicate,28.85%of soluble starch,and 6.49%of silicone oil.The lowest water permeability of the film is 379.645W VT.(5)Field experiment was carried out,detected the change of index which include the mulch preserving water,enhancing soil temperature,weight loss,changes in mechanical properties of bagasse mulch both surface and underground.The results indicated that the soil moisture above ground mulch is 2.6%higher than that of the control group.The soil moisture above underground mulch is 0.9%higher than that of the control group.The temperature of the soil above ground mulch increases by 0.50?-0.70?per day.The temperature of the soil above underground mulch increases by 0.33?-1.04?per day.After 72 days,the mechanical performance of ground test group drop to the range of 10N/m-20N/m.The above ground mechanical properties are close to zero after 49 days.The lowest quality loss rate after ground mulching test is 34.73%.The highest quality loss rate is 70.44%.The lowest quality loss rate after underground mulching test is 64.10%.The highest quality loss rate is 86.41%.