Depth analysis of interception principle of composite filter membrane

Composite filtration membranes are used in many industries, such as water treatment, pharmaceuticals, food processing, medical treatment, scientific research, etc., mainly used to separate and purify different components in the mixture, and achieve the separation effect by means of interception, that is, for different operating conditions The particles and solutes provide an efficient and selective barrier. This article provides an in-depth analysis of the interception principle of the composite filter membrane.

What is a composite filter membrane?

Composite filtration membranes are usually composed of two or more layers of different materials, each of which has a specific function and plays a different role in the filtration process. This layered structure allows simultaneous filtration of various particle sizes and solute types, which can Specific particles are oriented according to different pore sizes.

The structure of composite filter membrane?

1. The support layer, the support layer provides mechanical strength and stability for the entire membrane structure, it is usually composed of porous materials, allowing fluid flow while maintaining the integrity of the membrane.

2. Separation layer, the separation layer is responsible for selectively filtering particles and solutes, it is usually made of semi-permeable material, allowing some molecules to pass while retaining others.

3. Interface layer, the interface layer is responsible for maintaining the integrity of the composite membrane and ensuring a strong bond between the support layer and the separation layer, it is usually made of thin porous material to allow fluid flow while minimizing the risk of delamination.

What is the interception principle of the composite membrane?

The interception principle refers to the physical mechanism by which particles are removed from a fluid stream when they come into contact with a filter membrane, and it is one of several filtration mechanisms that can occur within a composite filter membrane, including sieving, diffusion, and adsorption. Under the action of pressure, the effect of separation, purification and concentration can be achieved.

What are the factors affecting composite membrane interception?

1. Particle size: The size of the particles in the fluid flow determines the probability of interception. Larger particles are more likely to be intercepted and retained by the membrane, while smaller particles are more likely to pass through. In the process of membrane selection, the size of the particles must be clarified, what is needed and what is not.

2. Membrane pore size: The pore size of the separation layer directly affects the effect and efficiency of the interception process. Smaller pore size will lead to increased interception, higher pressure, and lower efficiency, while larger pore size will allow more particles to pass through , the quality of filtering will be affected.

3. Flow rate: The flow rate of the fluid will also affect the interception process. A higher flow rate will increase the possibility of particles being in contact with the membrane, resulting in increased adsorption and accumulation of particles, affecting the life cycle of the membrane, and increasing the cost.

4. Membrane surface characteristics: Different membrane materials have different membrane surface characteristics, such as charge and hydrophobicity, which can affect the interaction between particles and the membrane, and ultimately affect the interception process.

A deep understanding of the interception principle and composition structure of the composite membrane, the factors of membrane interception, such as particle size, membrane pore size, flow rate and membrane surface characteristics, etc., is an important part of selecting a suitable filtration membrane, especially in large-scale production and filtration of complex mixtures. In each case, it is helpful to optimize the performance of these membranes in practical applications.

Citation

1.Van der Bruggen, B., Volodin, A., & Koltuniewicz, A. B. (2018). Composite membranes for water treatment: A review. Water Research, 133, 282-301.

2.Goh, P. S., & Ismail, A. F. (2017). A review on composite polymeric membranes for water treatment. Desalination, 420, 241-259.

3.Li, J., Wang, L., Liu, Y., & Zhang, J. (2015). Recent advances in composite membranes for osmotic power generation. Journal of Membrane Science, 475, 167-182.