Introduction to the types and characteristics of commonly used wire mesh corrugated packing

Commonly used metal wire mesh corrugated packing types and characteristics introduction-Anping County Maoqun Wire Mesh Manufacturing Co., Ltd.

Metal mesh corrugated packing is also known as stainless steel mesh packing, structured wire mesh packing, etc.

Metal wire mesh corrugated packing is an important milestone in the development of structured packing. It is a disc-shaped packing composed of several parallel and straight metal corrugated mesh sheets. First, small holes with a small density of 0.4-0.5mm in diameter are pressed out on the metal plate, and then the multi-perforated plate is pressed into corrugated sheets to assemble into structured packing. Due to the special puncture structure on the surface, the wetting performance of the packing is improved, and the performance of the metal wire mesh corrugated packing can be maintained. Stainless steel corrugated packing includes perforated plate corrugated packing, plate mesh corrugated packing, calendered perforated plate corrugated packing, wire mesh corrugated packing and ring-shaped corrugated packing.

Features of wire mesh corrugated packing:

The corrugated top angle of the wire mesh packing is about 90 degrees, and the channel formed by the corrugation is 45 degrees or 30 degrees to the vertical direction. The flow channels of the two adjacent corrugated sheets are 90 degrees, and the upper and lower plates of corrugated packing are rotated 90 degrees and stacked. In the tower with a smaller diameter connected by flanges, the corrugated packing is made into a whole disc, and the diameter is slightly smaller than the inner diameter of the tower. In the tower with a larger diameter, each plate of corrugated packing is divided into several pieces, put into the tower through the manhole, and assembled into a complete disc in the tower. The corrugated sheets of the upper and lower plates of packing are rotated 90 degrees to install, so that the fluid is fully mixed in the tower. It has the characteristics of thin wall, large porosity, large flux, light weight, small resistance, small gas phase passage angle, regularity, sufficient gas contact, good separation effect, high efficiency, and low pressure drop.

Application of wire mesh corrugated packing:

Metal mesh corrugated packing (stainless steel corrugated packing) is a highly efficient packing widely used in countries around the world, especially suitable for vacuum distillation towers. It is mainly used in petrochemical industry, fertilizer industry, natural gas purification, smelting, etc. Such as coal chemical industry (benzene washing tower for recovering crude benzene in coking plant), ethylbenzene separation, high-purity oxygen preparation, propylene oxide separation, debutanizer, cyclohexane recovery, gasoline fractionation, atmospheric and vacuum refining, etc. It is used as a packing in a three-phase separator or two-phase separator in the process of crude oil degassing and dehydration. It is especially suitable for treating heat-sensitive, easily decomposed, easily polymerized, and easily carbonized materials.

The wire mesh corrugated packing is a regular packing composed of vertically arranged corrugated wire mesh strips. The height of each packing is 40-300mm. The corrugation direction is 30° or 45% with the inclination angle of the tower axis. The two adjacent corrugations are in opposite directions. The packing plate diameter is a few millimeters smaller than the tower diameter, depending on the tower diameter. The packing plate precisely fills the tower cross section. The hoop on the outside of each packing plate can have a flange to prevent wall flow. The upper and lower adjacent plates are rotated 90° for filling. For small tower diameters, the packing is filled in the whole plate. For large towers with a diameter of more than 1.5m or towers without flange structures, the packing can be installed in blocks from the manhole into the tower and then assembled. The main materials for making wire mesh corrugated packing are stainless steel, copper, aluminum, iron, nickel, etc.

The mass transfer performance of metal wire mesh corrugated packing is directly determined by the specific surface area of the packing. According to the different specific surface areas, metal wire mesh packing can be divided into 250 type, 500 type and 700 type. Since metal wire mesh packing belongs to the liquid film mass transfer type, holes are opened on the corrugated packing sheet or double-layer wire mesh packing is made to strengthen the uniform distribution of liquid on the wire mesh corrugated sheet. Especially at low spray density, whether the liquid can be evenly distributed on the wire mesh sheet to form a film is the key to maintaining high separation efficiency.

There are small holes on the wire mesh corrugated sheet to enhance the uniform distribution of liquid and the renewal of liquid film, reduce dead corners in the packing (especially in small towers), and improve separation efficiency. In order to enhance the horizontal mixing of gas and liquid, the diameter of the small holes on the corrugated sheet should be 4-5mm.

Due to the geometric structure of the wire mesh corrugated packing, the following characteristics are formed:

1. Large specific surface area, high porosity, light weight. The specific surface area of 500 type packing is equivalent to 4.5 times that of Dg50mm metal ball ring (ball ring specific surface area 110m2/m3, density 800kg/m3), while the density is only 40% of the ball ring. The high porosity and strong capillary action of the wire mesh make it have excellent wetting performance. Even if the spraying density is 0.2m3/(m2?h), it can achieve complete wetting, so the packing efficiency is high.

2. The gas phase passage has a small inclination angle and a regular gas phase passage, resulting in less pressure loss and lower packing pressure drop.

3. Good radial diffusion and sufficient gas-liquid contact.

4. Avoid clogging, corrosion, and difficulty in cleaning, and can only be cleaned by chemical methods.

5. The unit volume filler has a high cost, which limits its scope of use.