Remanufacture Of Fine Rubber Powder From Waste Rubber Tires And Its Application

There is high recycling value of rubber components in waste tires,grinding used tires to make fine rubber powder is a relatively efficient and environment friendly remanufacturing process.Fine rubber powder has a wide range of applications.However,the current crushing of waste tire rubber has problems such as high cost,serious pollution,insufficient fineness,and low application value.Cryogenic crushing technology can easily crush rubber,which is difficult to be crushed at room temperature,and has the advantages of small power required for crushing and no secondary pollution.Therefore,it is of positive significance to study the cryogenic grinding of waste tires to obtain fine rubber powder and its application.The main research contents are as follows:(1)Through the cryogenic freezing test of rubber materials,the mechanical properties at ultra-low temperature were analyzed and the working mechanism of cryogenic grinding and crushing of rubber is studied.Based on this,the cryogenic pulverization method and cold source are analyzed and determined.In order to reduce the consumption of the cold source,the coarse crushing and its previous steps need only be performed at room temperature.Finally,the cryogenic milling preparation process of fine rubber powder for waste tires was determined.(2)To prepare fine rubber powder at ultra-low temperature,the overall layout and improved design of the original test device were carried out.Using this test device,liquid nitrogen was used as a cold source to prepare fine rubber powder at ultra-low temperature.Particle size analysis by laser particle size analyzer(up to 240 meshes).The effect of experimental parameters on the specific gravity of fine rubber powder was analyzed by orthogonal test.It is concluded that the degree of influence on them from the largest to the smallest is the gap between the grinding discs,rotation speed,feeding speed.Based on this,improving the test parameters and improving the yield of fine rubber powder.It can not only provide enough samples for subsequent tests,but also provide a reference for the industrial application of the prototype.(3)Microscopic surface morphology of fine rubber powders prepared under normal and ultra-low temperature conditions were observed by electron scanning electron microscopy(SEM).It was found that the surface of the rubber powder at room temperature was uneven and burr-like,and the surface of the rubber powder at ultralow temperature was smooth and the edges were obtuse.And it is easier to disperse in other matrix materials.The tensile,tear,and hardness properties of the 60-mesh,120-mesh,and 240-mesh blended vulcanizates were compared with those made at ultra-low temperatures.It was found that the incorporation of fine rubber powder will affect the properties of the blended rubber,which is mainly reflected in tensile strength,elongation at break,yield strength,tear strength lower than natural rubber,and the smaller the particle size,the higher these properties.The hardness is higher than natural rubber,and the smaller the particle size,the lower the hardness.A specific performance change trend chart is drawn,which provides a reference for subsequent applications.(4)Taking the tee in agricultural drip irrigation as an application object,a simple molding vulcanization mold for the three-way pipe was designed and manufactured.Using this mold,a rubber tee with 30 parts of 120 mesh waste rubber fine rubber powder was prepared.Comparing it with a tee that is not doped with fine rubber powder,it is found that when the aging time is 144 hours and the aging temperature is 50 ?,the appearance and morphology of the two are not much different,and the difference between the number of cracks and the depth is small.It can be considered that the substitution of fine rubber powder with some waste rubber is a good substitute for raw rubber.The purpose of this article is to prepare a fine rubber powder by using a cryogenic milling and pulverizing prototype to study its microscopic surface characteristics and mechanical properties,The rubber three way pipe for agricultural drip irrigation is used as an object to explore the use of fine rubber powder prepared at ultra-low temperature to partially replace raw rubber,and realize waste turning into treasure.