Towards negative CO2 emissions: energy and multiphase flow studies

提出了五个子项目，每个子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。将研究通过循环煅烧/碳化干燥吸附剂（例如白云石）捕获二氧化碳的变压方法，该方法适用于化学循环系统。重点将是结合廉价的吸附剂，防止或减少重复循环时的反应性损失。将测试快速减压、定期长时间碳化、预处理和镁吸附剂，在某些情况下可进行100 ~ 1000次循环。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。我们将进行气体和液体流化床中颗粒偏析的实验和计算流体动力学研究，以确定偏析的机制并开发改进的预测方法。早期的工作表明，目前的经验和半经验方法预测气体流化床颗粒携带的严重失败的一个重要原因可能是静电电荷对逸出颗粒和留在床中的颗粒的影响。我们将研究携带粒子上的静电荷及其影响。我们应用“流动流化床”来研究许多现代测量技术的性能和准确性，将通过对迄今为止在加拿大五所大学获得的数据进行严密的统计分析，并在研究生的陪同下将该装置送到美国和英国的设施，那里有独特的仪器能力。还将建立一个全面的数据库，供测试CFD代码使用。最后，我们的工作耦合互补氢化和脱氢过程的任何一侧的透选择膜，跨越氢和热传递，将被扩展。这将涉及一个实验概念验证研究，以及进一步的建模，其中一侧或两侧的固定床被流化床取代。这五个分项目中的每一个都将有助于训练高度合格的人员。

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.