Towards Realisation of Untapped Oil Resources via Enhanced THAI-CAPRI Process Using Novel Catalysts

加拿大和委内瑞拉存在大量未开发的重油和沥青资源，以及英国北海海底较重的矿藏，随着常规轻质原油产量的下降，这些矿藏可能会被利用。重油和沥青比常规原油更难回收，需要采矿或专门的现场回收技术，然后进行升级，使其适合用作燃料。脚趾到脚跟注气(THAITM)是一种将空气注入水平井以满足一小部分石油(高达15%)的燃烧的就地燃烧和升级过程。产生的热量使石油沿着油井流动，在那里发生热升级反应，导致石油升级(4-6API)。CAPRI是泰国的一种催化添加剂，它将催化剂堆积在井周围，以实现进一步的催化升级反应，如加氢处理，然而先前的研究表明，催化剂的寿命和工艺效率受到催化剂上积炭的限制。此外，在开车前用造粒催化剂填充油井的成本和挑战也使Capri工艺在经济上不那么吸引人。当前的提议寻求开发廉价、有效的纳米颗粒催化剂，这些催化剂可以在操作期间通过空气或浆料输送到油井中，从而避免在开车前用催化剂填充油井的要求，并减少由于颗粒催化剂上的焦炭沉积而发生的失活和床层堵塞的量。最初，容易获得的氧化铁纳米颗粒将作为基本情况进行测试。还将通过将金属支撑在细菌上来制备纳米颗粒催化剂，使用的方法是在细菌培养的情况下还原含有金属的溶液，然后进行离心机和干燥，从而杀死活细菌。该方法的优点是能够利用废金属溶液，从而促进从废源中回收金属，并且可以调整以设计出所需尺寸和性质(例如晶体结构)的纳米颗粒。在这里，我们寻求开发、测试和扩大生物铁催化剂的生产，用于泰国工艺的石油提质。此外，废弃的道路灰尘含有车用催化转化器废气中的催化金属沉淀物，这些金属将通过经过经济验证的生物湿法冶金方法转化为廉价的混合金属催化剂，在泰国的工艺中进行测试。利用纳米颗粒催化剂的有效性的关键是它们与发生反应的流动油区和油井前面的火焰接触的能力。将使用X射线微层析成像等技术对岩石空隙结构进行研究。蒙特卡罗和格子Boltzmann模拟将被用来研究颗粒进入储集层的气力输送，并研究颗粒在岩石空隙中的渗透和分布。浆料催化剂的输送和过程性能将使用STAR储罐模拟软件进行模拟。不同催化剂的评估将在真实条件下使用先前项目开发的试验台进行。将通过实验研究气油比、温度、压力和气体组成等变量的影响，以选择最佳催化剂并了解最大限度升级所需的条件。这些实验还将表明催化剂在使用过程中是否发生失活，并使条件得以调整以避免失活。

Extensive unexploited resources of heavy oil and bitumen exist, for example in Canada and Venezuela, as well as heavier deposits under the North Sea UK, which could potentially be utilized as the production of conventional light crude declines. Heavy oil and bitumen are more difficult to recover than conventional crude, requiring mining or specialized in-situ recovery techniques followed by upgrading to make them suitable for use as a fuel. Toe to heel air injection (THAITM) is an in-situ combustion and upgrading process in which air is injected to a horizontal well to feed combustion of a small fraction of the oil (up to 15 %). The heat generated causes the oil to flow along the well, where thermal upgrading reactions occur, leading to upgrading of the oil (by 4-6 API). CAPRI is a catalytic add-on to THAI in which catalyst is packed around the well to effect further catalytic upgrading reactions, such as hydrotreatment, however previous studies showed that the catalyst lifetime and process effectiveness are limited by coke deposition upon the catalyst. Additionally the costs and challenges of packing the well with pelleted catalyst prior to starting up also make the CAPRI process less economically attractive.The current proposal seeks to develop cheap, effective nanoparticulate catalysts which could be conveyed into the well by air or as slurry during operation, thereby avoiding the requirement for packing the well with catalyst prior to start up and to reduce the amount of deactivation and bed blockage that occurs by coke deposition upon pelleted catalysts. Initially, readily available iron oxide nanoparticles will be tested as a base-case. Nanoparticulate catalysts will also be prepared by supporting the metal upon bacteria, using a method in which metal containing solution is reduced in the presence of a bacterial culture, followed by centrifuge and drying which kills the live bacteria. The method has the advantages of being able to utilize scrap metal solutions and thus facilitate recycling of metals from waste sources, and it may be tuned to engineer nanoparticles of desired size and properties (e.g. crystal structures). Here we seek to develop, test and scale up the production of biogenic Fe catalysts for the upgrading of oil in the THAI process. Furthermore, waste road dusts contain deposits of catalytic metals from the exhaust of vehicular catalytic converters and these will be converted into cheap mixed metal catalysts by economically proven biohydrometallurgical methods for testing in the THAI process.Key to the effectiveness of utilizing nanoparticle catalysts will be the ability to contact them with oil in the mobile oil zone and flame front of the well, where the reaction is taking place. Studies of the rock void structure will be carried out using techniques such as X-Ray microtomography. Monte Carlo and Lattice Boltzmann simulations will be used to study the pneumatic conveying of particles into the reservoir and to study penetration and distribution of particles within the void space of the rocks. Conveying of slurry catalysts and process performance will be modeled using STARS reservoir simulation software.Evaluation of the different catalysts will be performed experimentally under real conditions using a rig developed under a previous project. The effect of variables such as gas:oil ratio, temperature, pressure and gas composition will be studied experimentally, in order to select the best catalyst and understand the conditions required for maximum upgrading. The experiments will also indicate whether catalyst deactivation occurs during use and enable conditions to be tuned to avoid deactivation.