基于微乳化调质预处理的含油污泥分离特性试验研究

发布时间：2018-05-02 19:19

本文选题：含油污泥 + 微乳液　；参考：《浙江大学》2017年硕士论文

【摘要】：作为世界第二大石油资源消耗国,我国的石油需求量和消耗量在逐年攀升。而在石油的开采、储运、炼制等过程中,不可避免地会产生含油固体废弃物,即含油污泥。据统计,我国每年产生的含油污泥将超过500万吨。含油污泥是一种危险废弃物,已被列入《国家危险废物名录》,必须对其进行妥善处置。同时,含油污泥的含油率较高,可回收其中的油分对其进行资源化利用。作为一种发展较为成熟的油泥资源化处理方式,离心分离具有操作简单、清洁低耗等优点,适合油泥资源化处理的工业化应用。然而油泥是一种油包水(W/O)型乳化液,黏度高,流动性差,不利于处理过程中的输送。而且油泥中的油-水乳化稳定,给离心脱水过程带来了很大的困难。为了获得高的离心分离效率,必须对离心分离之前的油泥进行预处理来破乳,达到降黏、增强脱水的目的。本文提出一种新的调质预处理方法-微乳化法,即利用微乳液具有超低的界面张力的特性对油泥进行破乳,主要围绕降低含油污泥黏度和脱除含油污泥中的乳化水两个方面开展了实验研究,得到的主要结果和结论如下:(1)对油泥原样的黏度特性进行分析发现,油泥属于典型的非牛顿流体,具有假塑性流体的特征,而且油泥的剪切稀释行为较一般稠油表现的更为明显。含有较多的胶质和沥青质等重质组分形成的大分子结构促进了油泥W/O型乳化液的稳定,油泥的W/O乳化状态是油泥表现出高黏特性的根本原因。采用流变模型对油泥的流变曲线进行拟合,结果显示P-L模型比较适合用来描述国炼油泥的流变行为。(2)考察了微乳液添加量、不同表面活性剂、表面活性剂复配对降黏效果的影响,结果表明:微乳液添加量为25%时,用SDBS作为表面活性剂,微乳液的降黏效果最好。降黏率达95%以上,尤其在99s-1下达到99.215%,油泥的流动性有了很大改善。综合考虑降黏效果和经济性,适宜选用SDBS和OP-10。用OP-10和SDBS按一定比例复配的表面活性剂较两者单独使用时的降黏效果要好,而且经济性得到提高。其中比例为2:1的降黏效果最佳,99 s-1下的降黏率可达99.436%。(3)通过DSC分析获得了添加微乳液预处理前后油泥样品离心分离各层的含水率及乳化水粒径变化,研究发现在一定离心参数下,由于油泥的乳化稳定性高,单纯的离心分离不能使油泥中的乳化水滴沉降。添加徽乳液预处理后,降低了油-水界面张力,油-水界面膜被破坏,经离心分离后,乳化水滴聚并沉积到下层得以脱除。(4)研究了微乳液中油相、助表面活性剂及表面活性剂复配对脱水效果的影响,结果表明:煤油为油相,正丁醇为助表面活性剂时,脱水率最高,可达94.60%。阳离子表面活性剂CTAB与非离子表面活性剂NP-10按1:6的比例进行复配时的脱水率为95.23%,要高于相同条件下单独使用NP-10作为表面活性剂的脱水率78.94%。通过2DNOESY核磁实验确定了两种复配的表面活性剂之间的相互作用点,这种相互作用使得复配的表面活性剂体系表面活性更高,更容易降低油-水界面张力,因此可以得到更好的破乳效果。
[Abstract]:As the second largest oil resource consuming country in the world, our country's oil demand and consumption are increasing year by year. In the process of oil mining, storage, transportation and refining, oil containing solid waste, that is oil sludge, is inevitable. According to statistics, the oil sludge will exceed 5 million tons per year in China. Oily sludge is a dangerous waste. The abandoned material, which has been listed in the national hazardous waste list, must be disposed of properly. At the same time, the oil content of the oily sludge is high, and the oil can be recycled. As a more mature way to treat the sludge, the centrifugal separation has the advantages of simple operation, low consumption and so on. It is suitable for the oil sludge resources. However, the oil sludge is a W/O type emulsion with high viscosity and poor fluidity, which is not conducive to transportation in the process. Moreover, the oil water emulsification in the oil sludge is stable, which brings great difficulties to the centrifugal dehydration process. In order to obtain high centrifugal separation efficiency, the sludge before centrifuge separation must be pretreated. In order to reduce the viscosity and enhance dehydration, a new quenching and tempering pretreatment method, microemulsion method, is proposed in this paper, that is, using the characteristics of ultra-low interfacial tension in microemulsion to demulsify oil sludge, mainly around two aspects of reducing the viscosity of oily sludge and removing the emulsified water from oily sludge. The main results and conclusions are as follows: (1) the analysis of the viscosity characteristics of the original oil sludge shows that the oil sludge belongs to the typical non Newtonian fluid and has the characteristics of pseudoplastic fluid, and the shear dilution behavior of the oil sludge is more obvious than that of the ordinary heavy oil. The large molecular structure of heavy components, such as many resins and asphaltenes, is promoted. The W/O emulsion is stable, the W/O emulsification of the sludge is the fundamental reason for the high viscosity of the sludge. The rheological model is used to fit the rheological curve of the sludge. The results show that the P-L model is suitable for describing the rheological behavior of the oil sludge. (2) the addition amount of microemulsion, the surface active agent and the surface activity are investigated. The effect of agent complex pairing on viscosity reduction shows that the viscosity reduction effect of microemulsion is best when the addition of microemulsion is 25% and SDBS is used as surfactant. The viscosity reduction rate is over 95%, especially under 99s-1, and the fluidity of the sludge is greatly improved. The efficiency and economy of viscosity reduction and the use of OP-10 and S for SDBS and OP-10. are considered. The viscosity reduction effect of DBS in a certain proportion is better than that used alone, and the economy is improved. The viscosity reduction effect of 2:1 is the best, the viscosity reduction rate under 99 S-1 can reach 99.436%. (3) through DSC analysis, the moisture content and emulsification of the centrifuge separation layers of the samples before the microemulsion pre treatment are obtained. With the change of water particle size, it is found that under certain centrifugal parameters, the emulsion droplets in the sludge can not be settled because of the high emulsifying stability of the oil sludge. The interfacial tension of oil water interface is reduced after the addition of emblem emulsion, and the oil water boundary mask is destroyed. After centrifugation, the emulsified water droplets gather and be removed to the lower layer to be removed. (4) The effect of oil phase, surface active agent and surface active agent on the dehydration effect of microemulsion was studied. The results showed that the dehydration rate was the highest when kerosene was oil phase and n-butanol as the surfactants. The dehydration rate of 94.60%. cationic surfactant CTAB and non ionic surfactant NP-10 according to the proportion of 1:6 was 95.23%, The dehydration rate of NP-10 as an active agent under the same condition is higher than that of 78.94%.. The interaction point between two kinds of compound surfactants is determined by the 2DNOESY NMR test. This interaction makes the compound surface active agent system more active and easier to reduce the oil water interfacial tension. Good demulsification.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X74

【参考文献】