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能源的持续供应，预计到2035年全球需求将增加50%。虽然化石燃料仍然是主要能源，但与供应安全相关的问题以及由于二氧化碳排放造成的环境影响将在可预见的未来限制其使用。低碳和可再生能源，如核能和生物燃料的使用越来越多，将逐步满足这些能源需求。来自裂变的核能是一种低碳能源，可以提供大量的电力和过程热，只需少量的原材料。然而，核燃料循环的主要关切之一是放射性废物的管理，这些废物可能在数千年内仍然有毒。核能发电的扩大使核废料管理问题特别尖锐。核燃料的后处理有可能回收剩余的锕系元素和裂变产物，并减少乏燃料的体积和毒性，以便在地质处置库中储存或处置。然而，后处理的成本很高，使得直接储存和最终处置高放射性废物成为首选方案。液-液萃取技术在乏核燃料后处理中至关重要，目前使用的接触器已有几十年的历史，并且没有很好的表征。在该项目中，我们将开发用于萃取过程的新型液-液接触器，以加强从替代和可持续来源生产能源。集约化解决了节约材料和能源的需求，并通过使工业流程更快、更高效和对环境的破坏更小，大大提高了全球加工工业的竞争力。使用小规模接触器可以实现显著的工艺强化，其中减小的长度尺度导致薄的流体膜，这提高了传质速率，而增加的表面积与体积比使得能够控制形成良好表征的流型。我们将开发两个概念，以加强液-液萃取，并将产量提高到工业水平。第一种方法涉及一个强化的撞击射流接触器，其中两个液相在接触器的小空间中以高速碰撞;在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窄分布的分散体，其具有大的界面面积。第二种方法涉及通过增加所使用的小通道的数量（横向扩展）来扩大过程。这种方法不同于传统的放大，其中单元尺寸增加，并且取决于供给通道的流量分配器的设计。该研究将与两个工业伙伴合作进行，即开发核燃料后处理技术的NNL和生产生物柴油的Greenegy。项目伙伴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.