Isothermal Refining by Organic Solvent Nanofiltration - ISOREF

在发达经济体中，原油精炼(仅次于化学品生产)是能源密集度第二高的行业。例如，炼油消耗的能源占美国总能源消耗的6%。目前的炼油技术是以蒸馏为基础，将原油分离成不同分子量的馏分，然后对其中一些馏分进行进一步反应(重整、加氢处理、裂化等)，然后必须进一步蒸馏。蒸馏包括通过沸腾将很大一部分液体原料转化为气体，这样原料中存在的化合物就可以通过它们的沸点差异来分离。在炼油中，蒸馏通常占总能耗的一半以上，因为沸腾时的相变需要大量的能量输入。避免这种巨大能耗的方法之一是通过膜在液体中进行分馏。如果碳氢化合物的混合物被压力压在膜上，而膜只对一些材料具有渗透性，那么我们就可以将通过膜的分子与不通过膜的分子分开。这避免了蒸发或蒸馏的大量能量注入。理论计算表明，膜分离浓缩混合物所需的能量不到蒸馏所需能量的5%。不足为奇的是，人们对使用膜分离和浓缩液体已经有一段时间了。到目前为止，大多数膜分离都是基于水的。一项重大成功是在海水淡化领域，该领域使用膜将淡水从海水中分离出来。在有机体系中，膜通常不用于分子分离，因为直到最近，在有机液体中稳定的膜还很少。这种情况最近发生了变化--帝国理工学院的研究已经开发出在大多数有机系统中都稳定的膜。这些已通过帝国剥离公司膜提取技术(MET)进行商业化，该公司于2010年3月1日被Evonik Industries收购。Evonik Met在伦敦西部的一家大型膜制造厂进行了大量投资，实现了英国政府制造未来的愿景。在许多情况下，所需的分离不能通过膜一次完成，因为膜不能高度区分存在的不同分子。在这些情况下，为了实现所需的分离，液体可以通过膜多次处理。这种膜的排列被称为膜级联。鉴于有机体系膜的发展及其在膜级联中的应用取得的进展，该项目将研究膜在精炼原油中的应用。膜不需要沸腾和冷凝，因此可以在单一温度下操作。这将减少对加热和冷却的需求，从而减少相关的热损失。因此，我们预计有机溶剂纳滤膜的等温精炼将显著降低从原油制造燃料和润滑油产品的能源需求。该项目将使用合成的清洁原油，由模拟真实材料的关键碳氢化合物组成。实验和模拟工作将被用来设计一种膜叶栅来分离合成原油；然后，该叶栅设计将被组装并运行以验证这一概念。然后，进一步的模拟将估计，如果对真正的原油采用等温精炼，将会节省多少能源。该项目将与合作伙伴壳牌戈巴尔解决方案公司密切合作，后者是炼油和炼油技术领域的大公司。

Crude oil refining is (after chemicals production) the second most energy intensive industry in advanced economies. For example, refining consumes 6% of the total energy used in the US. Current refinery technology is based on distillation for separation of the crude oil into fractions with varying molecular weights, followed by further reactions on some of these fractions (reforming, hydrotreating, cracking etc), which must then be further distilled. Distillation involves converting a large fraction of a liquid feed into a gas by boiling, so that compounds present in the feed can be separated by means of differences in their boiling points. In refining, distillation typically account for more than half of all the energy consumed, since the phase change on boiling requires significant energy input.One way of avoiding this large energy consumption would be to carry out fractionation in the liquid phase via a membrane. If a mixture of hydrocarbons is pressed by pressure against a membrane, and the membrane is permeable to only some of the materials, then we can separate the molecules that pass through the membrane from those that do not. This avoids the large energy injections of evaporation or distillation. Theoretical calculations show that the energy required for concentrating a mixture by membrane separation is less than 5% of the energy associated with distillation. Not surprisingly, people have been interested in using membranes to separate and concentrate liquids for some time. The majority of membrane separations to date are water based. A major success is in the area of desalination, where membranes are used to separate fresh water out of seawater. Membranes are not generally used for molecular separations in organic systems, because until recently there were few membranes stable in organic liquids. This has changed recently - research at Imperial College has developed membranes that are stable in most organic systems. These have been commercialised through an Imperial spin out company, Membrane Extraction Technology (MET) which was acquired by Evonik Industries on 1 March 2010. Evonik MET has made a substantial investment in a large scale membrane manufacturing facility in West London, delivering on the UK Government's vision for Manufacturing the Future.In many cases the required separation cannot be achieved in a single pass through a membrane, because the membrane does not discriminate highly enough between the different molecules that are present. In these cases, to achieve the required separation, the liquid can be processed through membranes multiple times. This arrangement of membranes is known as a membrane cascade.Given the advances that have been made in the development of membranes for organic systems and their application in membrane cascades, this project will research the use of membranes for refining crude oil. Membranes do not require boiling and condensation, and so can be operated at a single temperature. This will reduce the needs for heating and cooling, and so the associated heat losses. Thus we expect that isothermal refining with organic solvent nanofiltration membranes will significantly reduce the energy requirements for manufacturing fuels and lube products from crude oil.The project will work with a synthetic clean crude, made up to simulate the key hydrocarbon components of a real material. Experimental and simulation work will be used to design a membrane cascade to separate the synthetic crude; this cascade design will then be assembled and operated to prove the concept. Further simulations will then estimate what energy savings would result if isothermal refining were employed with a real crude. The project will work closely with partner Shell Gobal Solutions, who are a major company in oil refining and refinery technology.