Modelling and Control of Membrane Fouling in Ultrafiltration of Water and Wastewater

水和废水超滤中膜污染的建模和控制

• 批准号: RGPIN-2019-05644
• 负责人: Lohi, Ali
• 金额: $ 2.4万
• 依托单位: Ryerson University
• 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=747160
• 关键词: Modelling; Control; Membrane; Fouling; Ultrafiltration

Membrane filtration, such as ultrafiltration (UF), is an efficient and energy saving process that has been widely used in water purification, wastewater treatment, biotechnology, and oil-in-water emulsion separation. However, membrane fouling by the solutes/particles in a feed solution is a major challenge for the industry and has operational concerns that are currently hindering widespread application of membrane filtration. Membrane fouling causes a reduction of the permeating flux with time, resulting low filtration efficiency and higher filtration cost. Wastewater from paint manufacturers contains variety of substances, such as: organic/inorganic pigments, latex, solvents and emulsifying agents. Treatment of latex-paint wastewater with UF results in fouling, which causes a significant increase in hydraulic resistance, permeate flux decline and transmembrane pressure (TMP) increase. Through our previous studies, we have developed mechanistic models to predict membrane fouling, TMP, and power consumption using uniform and non-uniform pore size membranes. We also have developed innovative fouling remediation techniques capable of controlling membrane fouling in the cross-flow UF of latex effluent. For further development towards energy saving in pilot scale and industrial applications, there remains a need for a profound understanding of the following mechanisms: i) particle retention on the pore surface (pore constriction); ii) attachment on the membrane surface causing in blocking of the pore inlet, partially or completely (cake formation); iii) particle aggregation causing cake buildup; and iv) particle break-up behavior from the cake layers and reentering into retenate, and their effects on fouling. The objective of the proposed research is to use Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) to model the particle deposition on the plate-and-frame membrane, both inside the pore and on the surface, in relation to membrane fouling phenomena. Computing the trajectory of a particle to its final capture location involves both hydrodynamic and surface interactions. DEM will be coupled with CFD to study fluid-particle interaction systems occurring during membrane fouling in which both the solute (solid) and solution (fluid) phases contribute to the flow dynamics and particle deposition. A thorough understanding of this phenomenon and development of novel and innovative techniques to reduce membrane fouling through this research plan are of great importance to the industry. Main benefit arising from the proposed research plan is development of an innovative technique/method in designing separation/filtration membranes. This novel method will be achieved by combining our mechanistic fouling attachment model and the CFD-DEM model. The developed method will have a major impact on Canadian membrane manufacturers and membrane users. Training of HQP for the Canadian industry is an added benefit of the proposed research plan.

膜过滤（例如超滤（UF））是一种有效且节能的过程，已广泛用于水纯化，废水处理，生物技术和水中乳液乳液分离。但是，饲料溶液中溶质/颗粒在饲料溶液中污染的膜污染是该行业的主要挑战，并且在目前阻碍了膜过滤广泛应用的操作问题。膜结垢会随着时间的流逝而导致渗透通量减少，导致过滤效率低和较高的过滤成本。油漆制造商的废水包含多种物质，例如：有机/无机颜料，乳胶，溶剂和乳化剂。用UF处理乳胶粉的废水会导致结垢，从而导致液压耐药性显着增加，渗透到通量下降和跨膜压力（TMP）增加。通过我们以前的研究，我们开发了使用均匀和非均匀孔径膜的机械模型来预测膜结垢，TMP和功耗。我们还开发了能够控制乳胶废水跨流量中的膜污染的创新污染补救技术。为了进一步发展，在试点量表和工业应用中节省能源，仍然需要深入了解以下机制：i）在孔隙表面上保留粒子（孔隙收缩）； ii）附着在膜表面上的附着，导致孔隙入口的阻塞，部分或完全（蛋糕形成）； iii）粒子聚集导致蛋糕堆积；和iv）蛋糕层的颗粒破裂行为并重新进入重新进入及其对结垢的影响。拟议的研究的目的是使用计算流体动力学和离散元素方法（CFD-DEM）对板和框架膜上的粒子沉积建模，无论是在孔隙内还是表面上，都与膜结垢现象相关。计算粒子到其最终捕获位置的轨迹涉及流体动力和表面相互作用。 DEM将与CFD耦合，以研究在膜结垢过程中发生的流体粒子相互作用系统，在膜结垢中，溶质（实心）和溶液（液体）相都有助于流动动力学和颗粒沉积。对这种现象的透彻理解以及通过该研究计划减少膜结垢的新颖和创新技术的发展对行业非常重要。拟议的研究计划产生的主要好处是开发设计分离/过滤膜的创新技术/方法。通过将我们的机械结垢附件模型和CFD-DEM模型相结合，可以实现这种新颖的方法。开发的方法将对加拿大膜制造商和膜使用者产生重大影响。为加拿大行业培训HQP是拟议研究计划的额外好处。