【作者】 刘浩；

【导师】 杜芳林；

【作者基本信息】 青岛科技大学 ， 材料工程（专业学位）， 2020， 硕士

【摘要】 随着现代社会的进步,汽车数量的快速升高,废旧轮胎成为一个无法避免的环境问题,由于废旧轮胎不易被降解,又被称为黑色污染。目前废旧轮胎的处理方式有:露天放置、掩埋、轮胎翻修、码头鱼礁、焚烧、再生胶与胶粉、废旧轮胎热解等。研究表面,废旧轮胎热解技术对废旧轮胎的利用效率达到90%以上,热解产生的热解气,热解液,热解炭黑都可以用作工业原料使用。废旧轮胎热解炭黑的平均粒径达到了15.655μm,研究表明废旧轮胎热解炭黑主要来源于轮胎混炼中添加的各种炭黑;不同牌号的炭黑一部分保留原始尺寸,一部分烧结成大颗粒物质。热解炭黑表面存在大量的灰分,是普通商业炭黑的数倍,主要成分为Zn O、Si O₂、Zn S,这些不活泼的无机盐在废旧轮胎热解炭黑的表面形成了惰性层。并且热解炭黑的表面存在大量的大孔隙,微孔级别的空隙几乎不存在,使得废旧轮胎热解炭黑活性低,不易分散。颗粒平均粒径大,表面活性低都阻碍了废旧轮胎热解炭黑的应用。废旧轮胎热解炭黑的表面活化可以明显改善热解炭黑与橡胶大分子的结合方式。相比液相氧化改性废旧轮胎热解炭黑,行星球磨的方式是一种绿色的处理手段,且球磨后得到的小粒径的热解炭黑可以应用到多种环境中。合适的球磨参数是得到小粒径炭黑的关键。通过球磨中单磨球离散元分析,我们认为球磨中球磨类型、球磨时间、磨球种类、球料比、湿磨溶剂用量是影响球磨后热解炭黑平均粒径的关键因素。在不同的球磨实验中发现,在干磨中,单磨球质量较大的玛瑙磨球可以有效的避免物料固结的现象;粒径较小的氧化锆磨球在湿磨中可以明显降低废旧轮胎热解炭黑的平均粒径,得到纳米级的热解炭黑。在湿磨中,采用两种不同粒径的氧化锆磨球,研究了球磨时间,球料比、湿磨溶剂（乙醇）用量对球磨热解炭黑粒径的影响,三因素正交实验表明对球磨后热解炭黑的平均粒径影响顺序为乙醇用量>球料比>球磨时间。根据球磨原理可知,随着球磨时间的延长,热解炭黑的粒径呈现下降的趋势,当球磨时间达到一定时间后,行星球磨过程变成了粉碎与团聚的动态平衡,进一步延长球磨时间,废旧轮胎热解炭黑粒径不会发生明显的变化。随着球料比的增大,球磨后热解炭黑的粒径不断降低。球料比影响单位时间内物料与磨球的碰撞次数;球料比越大,物料与磨球的碰撞次数越大;球料比越小,物料与磨球的碰撞次数越小。在物料与磨球体积的限制下,随着球料比的增大,单位时间内与物料接触的磨球数量呈现先增大,后不变的趋势。随着乙醇浓度的增加,废旧轮胎热解炭黑颗粒粒径先减小后增大,乙醇用量多,物料的浓度降低,单位时间内物料与磨球、球磨罐的碰撞次数就降低,乙醇用量少,物料的浓度升高,物料容易团聚,不能很好的与磨球、球磨罐接触。采用0.5 mm氧化锆磨球在球磨时间3 h,球料比20,乙醇用量50 m L,球磨转速为320 r/min的球磨参数下,得到球磨废旧轮胎热解炭黑。并将球磨后的热解炭黑混炼到丁苯橡胶中。研究发现,行星球磨热解炭黑降低了废旧轮胎热解炭黑的粒径,增加了颗粒的表面能,提高了废旧轮胎热解炭黑在混炼胶的分散性,改善了炭黑颗粒与橡胶大分子链的结合状态。与混合同比例未球磨废旧轮胎热解炭黑的混炼胶对比,力学性能都得到了改善提高,并且随着废旧轮胎热解炭黑混合比例的提高,行星球磨对废旧轮胎热解炭黑的改性效果越明显。更多还原

【Abstract】 With the development of modern times,the amounts of vehicles increase rapidly and it’s obviously that environmental problems caused by waste tire cannot be avoided.As for the waste tire is not easy to degrade which it also be named as black pollution.At present,some ways to deal with waste tire include lay aside in an open-air,bury,retrofitting,reusing as artificial marine habitat,burning,recycling as rubber or powder,waste tire pyrolysis and so on.Studies shows that waste-tire pyrolysis technology is an effective way for utilization ratio of waste tire up to 90%.As for the pyrolysis gas,pyrolysis liquid and its black carbon produced from pyrolysis can be utilized as industrial material.The pyrolytic black carbon of waste tire,with average grain size up to 15.655μm,mainly comes from variety black carton of mixed refining of waste tire.The black carbon of different brands partly maintains its original dimension and parts of them is burned into large grains.A large amount of ash covering on the surface of pyrolytic black carbon is several times more than that of the ordinary business black carton,and its main ingredients are Zno,Si O₂ and Zn S which constitute the inert-layer on the surface of pyrolytic black carbon of waste tire.Meanwhile,on the surface of pyrolytic black carbon still exists a lot of macro-porosity and micro porosity is barely so that pyrolytic black carbon of waste tire owns low activity and is difficult to disperse.For the large average grain size and low activity surface will hamper the application of pyrolytic black carbon of waste tire.The surface activation of pyrolytic black carbon of waste tire is obviously effective to ameliorate combination of pyrolytic black carbon and rubber molecules.To compare with liquid oxidative-modification of pyrolytic black carbon of waste tire,superfine grinding is a more environmental way and its grinding grains of pyrolytic black carbon can be used in various situation.In order to attain small grain size,it’s crucial to use appropriate parameter in ball grinding.Through discrete-element analysis of single mall in grinding,we find in the progress of ball grinding,the grinding type,grinding time,types of grinding malls,proportion of ball materials,volume of solvent of wet grinding,all is the key point to influence the average grain size after ball grinding.In different experiments of ball grinding,it shows that in dry grinding,the larger agate ball of single ball can avoid effectively materials consolidation.As for zirconium oxide with smaller grain size in the wet grinding is obviously reduce the average grain size of black carbon of waste tire,which attains nano scale of pyrolytic black carbon.For the wet grinding,two different grain size of zirconium oxide mall was used to research how the grinding time,mall proportion,volume of solvent（ethanol）of wet grinding influence the grinding grain size of pyrolytic black carbon.In the orthogonal experiment with three factors shows that after ball grinding,the effect sequence of average grain size of pyrolytic black carbon ranks as ethanol volume>mall proportion>grinding time.According to ball-grinding principle,with the prolonging of mall-grinding time,the grain size of pyrolytic black carbon presented declining trend and it will come into milling and reunion in the progress of superfine grinding after a certain timeTo achieve a dynamic balance,with further prolonging of ball milling time,the grain size of pyrolytic black carbon of waste would not change apparently.And with increasing ball proportion,the grain size of pyrolytic black carbon of waste constantly decrease.The balls materials proportion has influence on the collision times of materials and milling balls in the unit time.With larger proportion of the balls,it’s more collision times of materials and milling balls but on the contrary,the smaller proportion of the balls,the less collision times is.Under the limitation of the materials and volume of milling balls,with the enlarging proportion of balls materials,the amounts of milling balls toughing with materials in unit time firstly increases,and then keep constant.With increasing density of ethanol,the grain size of pyrolytic black carbon of waste firstly decrease and then increase.With increasing dosage of ethanol and decreasing density of materials,the less times of materials collides with milling balls and milling container.With decreasing dosage of ethanol and increasing density of materials,it is more easily for materials reunite which can not well tough with milling balls and milling container.The milling parameter is used in adopting 0.5mm zirconium oxide in 3h milling time with 20 materials proportion,50ml ethanol and 320 r/min milling rotational speed which attains grinding pyrolytic black carbon of waste tire and adds into the mixture refining of Polymerized Styrene Butadiene Rubber.The research shows that the pyrolytic black carbon of superfine grinding reduces the grain size of pyrolytic black carbon of waste tire which enlarges the surface energy of particle,enhances the dispersiveness in mixture refining of pyrolytic black carbon of waste tire and improve the combination state of black-carbon particle and rubber molecules.To compare mixture refining rubber from black carbon of waste tire with which is non-grinding with same mixture proportion,mechanical properties has been well ameliorated and improved.Meanwhile,with the increasing mixture proportion of pyrolytic black carbon of waste tire,it shows more apparently modified effect of superfine grinding on pyrolytic black carbon of waste tire.更多还原