Interaction Between Gas-Liquid Jets and Fluidized Beds

气液射流与流化床之间的相互作用

• 批准号: 346287-2013
• 负责人: Salcudean, Martha
• 金额: $ 1.68万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=572533
• 关键词: Interaction; Between; Gas; Liquid; Jets

A fluidized bed occurs, under appropriate conditions, when one injects pressurized gas into a bed of small particles through a distributor. In fluidized beds, the particle-gas mixtures behave and can be handled like fluids - they flow, can be pumped, heated, used to mix or separate layers, and can operate continuously. Therefore, they are widely used in the oil, pharmaceutical, food and other industries. In many industrial fluidized bed reactors such as fluid catalytic cracking units, coaters and fluid cokers, the reactant feed is introduced into the system in the form of a gas jet or spray for different purposes. For example, bitumen is sprayed in the fluid coking process, which upgrades bitumen by means of thermal cracking. The liquid bitumen and steam are passed through a nozzle, atomized and injected horizontally into the reactor. The liquid bitumen coats the small solid particles (coke) and chemical reactions occur that produce the desired product. It is important to understand the physical phenomena that occur in the nozzle and in the fluidized bed in the vicinity of the nozzle in order to make sure the coating is uniform and no undesired agglomeration occurs. Agglomeration occurs often when liquid is sprayed into fluidized beds and an agglomerate of particles with liquid trapped inside forms. It can be a desired effect in certain processes, for instance in some pharmaceutical and food processing reactors, or undesirable as in the coking process. For all of these processes, it is important to have a good understanding of the interaction between the jets and the fluidized beds in order to understand the fluid distribution, mixing, coating and agglomerate formation and breakup. The applicant will investigate jet-fluidized bed interaction and will develop novel mathematical models that describe the process and enhance our understanding of the physical phenomena involved. The potential applications of the model to industry are widespread because they allow for process design and operational improvements that enhance the reactor efficiency and increase yield. Improved processes lead to energy savings and less impact on the environment.

在适当的条件下，当人们通过分配器将加压气体注入小颗粒床时，就会形成流化床。 在流化床中，颗粒-气体混合物的行为和处理方式与流体类似——它们流动、可以泵送、加热、用于混合或分离各层，并且可以连续运行。 因此，它们广泛应用于石油、制药、食品等行业。 在许多工业流化床反应器中，例如流化床催化裂化装置、涂布机和流化焦化装置，出于不同目的，反应物进料以气体射流或喷雾的形式引入系统中。例如，在流化焦化过程中喷洒沥青，通过热裂解来升级沥青。液体沥青和蒸汽通过喷嘴，雾化并水平注入反应器。液体沥青覆盖小固体颗粒（焦炭）并发生化学反应，产生所需的产品。重要的是要了解喷嘴和喷嘴附近的流化床中发生的物理现象，以确保涂层均匀并且不会发生不希望的结块。当液体被喷入流化床时，经常会发生附聚，并且形成内部截留有液体的颗粒附聚物。它可能是某些过程中所期望的效果，例如在一些制药和食品加工反应器中，或者是不期望的，如焦化过程中。对于所有这些过程，重要的是要充分了解射流和流化床之间的相互作用，以便了解流体分布、混合、涂层以及附聚物的形成和破碎。申请人将研究射流流化床相互作用，并将开发新颖的数学模型来描述该过程并增强我们对所涉及的物理现象的理解。该模型在工业中的潜在应用非常广泛，因为它们允许进行工艺设计和操作改进，从而提高反应器效率和产量。改进的流程可以节省能源并减少对环境的影响。