Ⅰ.Gas-solid filtration and separation

Gas-solid filtration and separation refers to the use of filter media (such as filter cloth, filter mesh, porous materials, etc.) to intercept solid particles in the gas separation process, which is widely used in dust removal, air purification, chemical production and other fields. Its core principles can be divided into the following six categories:  

1. Direct Interception

– Principle: When the particle size is larger than the pore size or fiber gap of the filter media, the particles are directly blocked on the surface of the media.  

– Characteristics: Suitable for larger particles (usually >1 μm), filtration efficiency depends on the pore size of the media.  

– Application: Primary air filter, metal filter dust removal.

2. Inertial Impaction

– Principle: When high-speed airflow carries particles through the filter media, the particles are unable to turn with the airflow due to inertia, and are captured by hitting the fiber or media surface.  

– Characteristics: Effective for medium-sized particles (0.3-10 μm), the higher the airflow speed, the higher the efficiency.  

– Application: bag filter, fiber filter.

3.Diffusion Deposition

– Principle: Small particles (<0.3 μm) are trapped by Brownian motion and randomly move to collide with each other or with the surface of the filter media.  

– Characteristics: Effective for sub-micron particles (e.g. PM2.5, smoke), and more effective at low air speeds.  

– Application: High-efficiency air filter (HEPA), medical purification equipment

4.Gravitational Settling

– Principle: In low-flow filtration systems, large particles settle naturally to the surface of the media by gravity.  

– Characteristics: Only for large particles (>10 μm), often in combination with other mechanisms.  

– Application: Combined systems of settlement chambers and filters.

• Electrostatic Deposition

– Principle: If the filter media or particles are electrically charged, particle adsorption is enhanced by electrostatic forces (Coulomb forces, etc.).  

– Characteristics: Enhanced capture efficiency of fine particles (0.01-1 μm), low energy consumption.  

– Applications: Electrostatically enhanced filter media, electret filters.

• Straining

– Principle: particles are mechanically retained because their size is larger than the pores of the filter media, similar to the role of a sieve.  

– Characteristics: suitable for high concentration, large particle separation, but easy to clog.  

– Application: metal sintered filter, ceramic filter element.

 The six principles of gas-solid filtration and separation usually work synergistically, and the actual filtration efficiency depends on:  

– Particle size (large particles are dominated by interception and inertia, small particles are dominated by diffusion and electrostatics)  

– Filter media characteristics (pore size, porosity, chargeability)  

– Airflow conditions (velocity, temperature, humidity)

Ⅱ. Nanjing Shinkai Filtration – Solution Provider

Nanjing Shinkai Filter Co.,Ltd. is a high-tech enterprise producing metal filtration membrane and precision filtration system, metal filtration membrane and precision filtration system is relying on the above filtration mechanism to work, Shinkai also developed a pressurized blowback gas-solid separation filtration system and on-line pulse blowback filtration system especially for the highly corrosive, high-temperature and high-concentration pollutant working conditions.

Shinkai has provided many well-known enterprises with high-performance, high-quality products, which greatly improve production efficiency and safety.

Pressurized blowback filtration systems are used for industrial exhaust gas and industrial steam filtration, as well as for applications that do not allow the use of conventional particulate control devices (e.g., baghouse), such as filtration of dirt in high temperature gases and rust or pipe scale in steam.

In-line pulse blowback filtration systems are ideally suited for systems that require continuous filter operation, where the filter consists of multiple cartridges grouped together and can be pulsed sequentially without dismantling the filters, while other cartridges that are not being pulsed are still functioning normally.

If you have any questions or would like to learn more about our products, installing or replacing a filtration system, please feel free to contact us! Our team of professionals will meet your complex filtration needs and provide or customize the most appropriate product for you.