Novel intensified liquid-liquid contactors for mass transfer in sustainable energy generation.

全球人口的快速增长和经济发展的动力依赖于持续的能源供应，预计到2035年，全球需求将增加50%。尽管化石燃料仍然是主要能源，但在可预见的未来，与供应安全和二氧化碳排放对环境影响相关的问题将限制它们的使用。越来越多地使用的低碳和可再生能源，如核能和生物燃料，将逐步满足这些能源需求。核裂变产生的核能是一种低碳来源，只需使用少量原材料就能提供大量电力和加工热能。然而，核燃料循环中的主要问题之一是放射性废物的管理，这些废物可能会在数千年内保持有毒。核电发电量的扩大使核废料管理问题变得尤为尖锐。核燃料的后处理有可能回收剩余的氡化物和裂变产物，并减少用于储存或处置在地质储存库中的乏燃料的体积和毒性。然而，后处理成本很高，这使得直接储存和最终处置高放射性废物成为首选选择。液-液提取技术在乏核燃料后处理中是必不可少的，目前使用的接触器有几十年的历史，而且没有很好的特性。在这个项目中，我们将开发用于提取过程的新型液-液接触器，这将加强替代和可持续来源的能源生产。集约化解决了对材料和能源节约的需求，并通过使工业过程更快、更有效、对环境的破坏更小，大大提高了世界各地流程工业的竞争力。通过使用小型接触器，可以大幅强化过程，其中减少的长度结垢可以产生增强传质速率的薄膜，而增加的表面积与体积比能够控制形成特征良好的流型。我们将提出两个概念，以加强液-液提取和提高产能到工业水平。第一种方法涉及强化撞击射流接触器，两液相在接触器的小空间内以高速碰撞；碰撞区域的强烈混合和高能量耗散率形成具有小液滴尺寸和具有大界面面积的窄分布的分散。第二种方法涉及通过增加使用的小通道的数量(向外扩展)来扩大该过程。这种方法不同于传统的扩大单元尺寸的放大方法，并且取决于为通道提供给水的流量分配器的设计。这项研究将与两个工业合作伙伴合作进行，即开发核燃料后处理技术的NNL和生产生物柴油的Greenegy。合作伙伴对该项目的积极参与和支持将促进技术转让。

The rapid growth of the population worldwide and the drive for economic development rely on continuous supply of energy, with global needs estimated to increase by 50% by 2035. Although fossil fuels are still the primary energy source, the problems associated with security of supply and the environmental impact because of the CO2 emissions, are going to limit their use in the foreseeable future. Low carbon and renewable energy sources, such as nuclear and biofuels, which are increasingly used, will meet progressively these energy demands. Nuclear energy from fission is a low carbon source and can provide large amounts of electricity and process heat using only small amounts of raw material. However, one of the main concerns in the nuclear fuel cycle is the management of the radioactive waste which can remain toxic for thousands of years. The expansion in nuclear power generation makes the problem of nuclear waste management particularly acute. Reprocessing of nuclear fuel can potentially recover the remaining actinides and fission products, and reduce the volume and toxicity of the spent fuel for storage or disposal in geological repositories. However, reprocessing has been associated with high costs, making the direct storage and ultimate disposal of high level waste the preferred option. Liquid-liquid extraction technologies are essential in spent nuclear fuel reprocessing where currently used contactors are decades old and are not well characterised.In this project we will develop novel liquid-liquid contactors for extraction processes that will intensify the production of energy from alternative and sustainable sources. Intensification addresses the need for materials and energy savings and contributes significantly to the competitiveness of process industries worldwide by making industrial processes faster, more efficient and less damaging to the environment. Substantial process intensification is possible with the use of small scale contactors, where the reduced length scales result in thin fluid films which enhance mass transfer rates, while the increased surface to volume ratios enable the controlled formation of well characterised flow patterns. We will develop two concepts to intensify liquid-liquid extractions and increase throughputs to industrial levels. The first approach involves an intensified impinging-jets contactor, where the two liquid phases collide at high velocities in the small space of the contactors; the intense mixing and high energy dissipation rates at the zone of collision form dispersions with small drop sizes and narrow distributions that have large interfacial areas. The second approach involves scale up of the process by increasing the number of small channels used (scale out). This approach differs from conventional scale up where the unit size is increased, and depends on the design of the flow distributor that feeds the channels. The research will be carried out in collaboration with two industrial partners, i.e. NNL which develops nuclear fuel reprocessing technologies and Greenegy that produces biodiesel. The active involvement and support of the partners in the project will facilitate technology transfer.