Investigation of electrostatic charging in various gas-solid processes including fluidization and pnumatic conveying

研究各种气固过程（包括流化和气力输送）中的静电充电

• 批准号: RGPIN-2018-05266
• 负责人: Mehrani, Poupak
• 金额: $ 2.04万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=746800
• 关键词: Investigation; electrostatic; charging; various; gas

In many gas-solid processes such as fluidization, pneumatic conveying, grinding, mixing, etc., electrostatic charges are generated during particle handling, transport and processing in which resulting in particle-wall adhesion, particle agglomeration, and generation of high-voltage electrical fields causing explosions. The significant negative impact of electrostatic phenomenon has been reported in various industries. In the petrochemical industry, a fouling incident in polyethylene gas-solid fluidized bed reactors could result in major economic losses of nearly $1.0M/day. In the case of pharmaceuticals, drug powder agglomeration and deposition occurs inside dry powder inhalers (used by those who suffer from lung illnesses such as asthma) which in turn reduces the efficiency of the inhaler by limiting the emitted dose. In the chemical industry, during grinding of solids such as cement or minerals a considerable amount of charge is generated leading to particle agglomeration which is quite undesirable because finely ground particles appear larger than they actually are, appreciably reducing grinding efficiency of the process. There is a great deal of need to determine ways to prevent or eliminate generation of electrostatic charges in industrial polyethylene gas-solid fluidized bed reactors, as well as shed some light on particle charging mechanisms in different gas-solid processes such as those of pneumatic conveying and grinding. The proposed research program will (a) use a state-of-the-art pressurized pilot plant gas-solid fluidization infrastructure that is able to operate at high pressures of up to 2500 kPa, 110C and houses a novel electrostatic charge measurement technique to determine the effects of fluidization temperature and presence of catalyst on the reactor fouling; (b) provide a thorough understanding of solids charging due to pneumatic conveying including the impact of catalyst electrostatic charging while being injected into the polyethylene fluid bed reactors; (c) develop an Euler-Euler Computational Fluid Dynamic (CFD) model enabling the prediction of particle charging in various gas-solid processes including those of fluidized beds; and (d) provide a comprehensive study of solids charging in grinding process to improve the grinding efficiency in the chemical industry. The anticipated impact of the research program is to assist industries including petrochemical and chemicals, sectors of vital importance to the Canadian and world economies, to gain a better understanding of the electrostatic charging mechanisms and to reduce operational challenges faced by these industries.

在流态化、气力输送、研磨、混合等许多气固过程中，颗粒处理、运输和加工过程中会产生静电荷，导致颗粒壁粘附、颗粒团聚以及产生高压电。引起爆炸的磁场。静电现象在各个行业中都有显着的负面影响。在石化行业，聚乙烯气固流化床反应器的一次结垢事件可能会造成近100万美元/天的重大经济损失。就药品而言，干粉吸入器（由患有哮喘等肺部疾病的人使用）内部会发生药物粉末结块和沉积，这反过来又会限制释放剂量，从而降低吸入器的效率。在化学工业中，在研磨水泥或矿物等固体的过程中，会产生大量电荷，导致颗粒团聚，这是非常不希望的，因为细磨的颗粒看起来比实际大，从而明显降低了过程的研磨效率。非常需要确定防止或消除工业聚乙烯气固流化床反应器中静电荷产生的方法，并阐明不同气固过程（例如气力输送过程）中的颗粒充电机制和研磨。拟议的研究计划将 (a) 使用最先进的加压中试工厂气固流化基础设施，该基础设施能够在高达 2500 kPa、110C 的高压下运行，并采用新颖的静电荷测量技术来确定流化温度和催化剂的存在对反应器结垢的影响； (b) 全面了解气力输送引起的固体充电，包括注入聚乙烯流化床反应器时催化剂静电充电的影响； (c) 开发欧拉-欧拉计算流体动力学（CFD）模型，能够预测各种气固过程（包括流化床过程）中的颗粒荷电； (d) 对研磨过程中的固体充电进行全面研究，以提高化学工业中的研磨效率。该研究计划的预期影响是帮助石化和化学品等对加拿大和世界经济至关重要的行业，更好地了解静电充电机制，并减少这些行业面临的运营挑战。