【作者】 刘苗苗；

【导师】 王宗贤；

【作者基本信息】 中国石油大学 ， 应用化学， 2007， 硕士

【摘要】 蜡的存在严重影响道路沥青的使用性能,蜡使路面夏季发软易形成车辙,冬季发脆易形成裂缝,因此开发降低蜡含量的新工业技术具有重大意义。本文采用化学热处理法降蜡,以蜡含量较高的中间-石蜡基属的减渣LYVR为考察对象,结合沥青质理论研究,筛选了两种添加剂沥青质分散稳定剂和油浆供氢剂馏分,考察了原料单独热处理及与添加剂混合热处理对蜡含量的影响,揭示了热处理降蜡的适宜条件及其物理化学本质,并在此基础上调制出了多种道路沥青产品。本文首先从渣油生焦的关键组分沥青质入手,为热处理降蜡筛选抑制生焦的添加剂,在生焦率低于0.1w%的前提下,提高热裂解降蜡的深度。实验表明,沥青质分散稳定剂在常温和热作用下均可降低沥青质分子的缔合作用,在渣油热反应体系中可减弱由沥青质分子物理凝聚引起的相分离,对生焦起物理延迟作用;油浆供氢剂馏分可提供活泼氢抑制缩合反应,对生焦起化学延迟作用。然后将减渣LYVR进行热处理,考察蜡含量的变化。结果表明,高温短时间比低温长时间的条件更有利于蜡含量的降低。单独热处理,蜡含量最低降至3.3w%,降蜡率为19.5%;与添加剂混合热处理以提高裂解深度,蜡含量最低降至2.2w%,降蜡率为46.3%。对于蜡含量稍高于3.0w%的孤岛减渣,仅通过单独热处理便可将蜡含量降至2.8w%。最后通过对原料LYVR热处理后大于500℃残渣组分各项性质的分析,选用蜡含量降至2.5w%的残渣组分进行沥青调和实验,结果表明,与原料LYVR、油浆或油浆重馏分调配可得到满足多种质量标准的道路沥青产品。更多还原

【Abstract】 Performances of paving asphalts are markedly influenced by waxes, such as forming ruttings in summer and splits in winter, so it is very important to develop new methods for dewaxing. With vacuum residue LYVR as testing sample and thermal treatment as experimental method, this thesis aims to: 1) select additives to suppress coke formation during thermal treatment according to the theory of residue asphaltene, 2) investigate the influence of thermal treatment on wax-content, optimize dewaxing condition, and formulate highway paving asphalts.Firstly, some additives were selected on the basis of residue asphaltene which is the key element for coke formation during thermal treatment. The results were as follows: 1) at normal or high temperature, the selected asphaltene dispersant could reduce the association of asphaltene molecules, 2) hydrogen-transfer of FCC decanted oil and its sub-fractions were evaluated by using anthracene and 9,10-dihydroanthracene as chemical probes, one of sub-fractions could be taken as hydrogen-donor. During thermal treatment, the asphaltene dispersant can decrease phase separation caused by physical congregation of asphaltene molecules, which is physical-delay effect, the sub-fraction of FCC decanted oil can give active H to suppress condensed reactions, which is chemical-delay effect. Secondly, vacuum residue LYVR was treated by employing an autoclave. It was found that the condition of high temperature and short time was beneficial to reduce wax-content compared with that of low temperature and long time. When LYVR was treated alone, the minimum wax-content was 3.3w%, the wax-content decreased by 19.5%. When LYVR was treated with additives, the minimum wax-content was 2.2w%, the wax-content decreased by 46.3%. As to another vacuum residue GDVR, the wax-content of which was a little higher than 3.0w%, after treated alone, its wax-content decreased to 2.8w%.Lastly, a comprehensive evaluation of treated residue samples(>500℃) was made in this thesis and the one with wax-content of 2.5w% was selected to produce paving asphalts. The results showed that some kinds of highway paving asphalts were formulated by blending with vacuum residue LYVR, FCC decanted oil or heavy fraction of FCC decanted oil.更多还原