Towards negative CO2 emissions: energy and multiphase flow studies

提出了五个次级项目，每个次级项目都可以直接或间接地促进提高效率和减少温室气体排放。将开展适用于化学循环系统的干吸附剂(如白云石)的循环焙烧/碳化变压捕集二氧化碳的研究。重点将是将廉价的脱硫剂与预防或减少重复循环时的反应性损失相结合。将测试快速减压、定期延长碳化、前处理和镁脱硫剂，在某些情况下用于&gt；1000循环。化学环和其他能量系统遇到的一个问题是，随着反应的进行，粒子密度会发生变化。我们将对气态和液态流态化中的颗粒分离进行实验和计算流体力学研究，以确定分离的机理，并开发改进的预测方法。早期的工作表明，目前预测气态床颗粒夹带的经验和半经验方法失败的一个重要原因可能是静电电荷对逃逸的颗粒和留在床上的颗粒的影响。我们将研究夹带粒子上的静电电荷及其影响。我们将通过对五所加拿大大学迄今获得的数据进行仔细的统计分析，并在一名研究生的陪同下，将该装置送到美国和英国的设施，在那里具有独特的仪器能力，从而完成我们对许多现代测量技术的性能和准确性的调查应用。还将建立一个全面的数据库，供测试CFD代码使用。最后，我们在膜两侧互补加氢和脱氢过程的耦合方面的工作将得到扩展，氢和热通过选择性膜传递。这将涉及一项实验性的概念验证研究，以及进一步的模拟，其中一侧或两侧的固定床被流态化床取代。这五个次级项目中的每一个都将有助于培训高素质人员。

Five sub-projects are proposed, each of which can contribute directly or indirectly to greater efficiency and reduced greenhouse gas emissions. Research will be conducted on pressure swing capture of CO2 by cyclic calcination/carbonation of dry sorbents (e.g. dolomite), applicable to chemical looping systems. The focus will be on combining inexpensive sorbents with preventioin or reduction in loss of reactivity upon repeated cycling. Rapid depressurization, periodic prolonged carbonization, pre-treatment and magnesium sorbents will be tested, in some cases for >1000 cycles. One issue encounterd with chemical looping and other energy systems is variation in particle density as reactions proceed. We will undertake an experimental and computational fluid dynamics study of particle segregation in gas- and liquid-fluidized beds to determine the mechanisms of segregation and to develop improved predictive methods. Earlier work has indicated that a significant cause of the abject failure of current empiical and semi-empirical methods of predicting particle entrainment from gas-fluidized beds may be the influence of electrostatic charges on the escaping particles and those left behind in the bed. We will investigate electrostatic charges on entrained particles and their influence. Our application of a "travelling fluidized bed" to investigate the perfomance and accuracy of a number of modern measurement techniques will be completed by close statistical analysis of the data obtained so far at five Canadian universities, and by sending the unit, accompanied by a graduate student, to facilities in the US and UK where there are unique instrumental capabilities. A comprehensive database will also be established and made available for testing of CFD codes. Finally, our work on coupling of complementary hydrogenation and dehydrogenation processes on either side of a permselective membranes, across which hydrogen and heat are transferred, will be extended. This will involve an experimental proof-of-concept study, as well as further modelling where the fixed bed on one or both sides is replaced by a fluidized bed. Each of these five sub-projects will contribute to the training of highly qualified personnel.