In chemical engineering, a filler refers to an inert solid material contained in a packed column, such as a Pall ring and a Raschig ring, etc., which serves to increase the gas-liquid contact surface and strongly mix them with each other.
In chemical products, fillers, also known as fillers, refer to solid materials used to improve processability, mechanical properties of the product, and/or reduce costs.
In the field of sewage treatment, it is mainly used in the contact oxidation process, and microorganisms will accumulate on the surface of the filler to increase the contact with the surface of the sewage and degrade the sewage.
One or two rectangular holes are formed in the side wall of the ring, and the base material of the small holes does not detach from the side wall but forms an inwardly curved blade. The upper and lower rectangular holes are staggered.
Although the same size of the Pall ring and the Raschig ring have the same specific surface area and void ratio, the small hole of the Pall ring on the side wall can be used for gas-liquid circulation, so that the inner wall surface of the ring can be fully utilized.
Compared with the Laxi ring, the Pall ring not only has a large production capacity and a low pressure drop, but also has a high separation efficiency and a greatly reduced channeling phenomenon.
The excellent properties of the Pall ring packing have always been valued by the industry and are widely used. It can be made of ceramic, metal or plastic.
2. Step ring packing
The stepped ring is typically made of Plastic Cascade Ring and metal and is widely used because of its superior performance to the open-cell fillers on other sidewalls.
The performance of the filler is often measured by three factors: efficiency, flux and pressure drop.
(1). Under the same conditions, the larger the specific surface area, the more uniform the gas-liquid distribution, the better the wetting property of the surface, and the higher the mass transfer efficiency;
(2). The larger the void ratio, the larger the flux and the lower the pressure drop;
(3). The mesh corrugated packing has the best comprehensive performance, and the Lacy ring is the worst.