The tower equipment is the most significant equipment in the petrochemical industry. In the tower equipment, the gas-liquid or liquid-liquid two-phase can be fully contacted, and the mass transfer between the phases can be carried out. Therefore, the tower equipment is commonly used in the production process for distillation, absorption, desorption, gas The unit operation process of humidification and cooling.
2. Plate distillation column
The tray tower is a step-by-step contact gas-liquid mass transfer equipment, which is mainly composed of a cylindrical shell, a tray, an overflow weir, a downcomer and a liquid receiving tray.
Principle: The liquid relies on gravity to flow from the downcomer of the upper tray to the liquid receiving tray of the lower tray, and then flows laterally through the tray, and flows from the downcomer on the other side to the next tray. The function of the overflow weir is to maintain a certain thickness of liquid layer on the tray. Driven by the pressure difference, the gas passes through the gas channels (bubble caps, sieves or float valves, etc.) of each layer of trays from bottom to top, disperses into small streams, and bubbles through the liquid layer of each layer of trays. . On the tray, the gas-liquid two phases are in close contact to exchange heat and mass. In the plate tower, the two phases of gas and liquid are contacted step by step, and the composition of the two phases changes in a stepwise manner along the height of the tower. Under normal operation, the liquid phase is the continuous phase, and the gas phase is the dispersed phase.
3. Gas cooling tower
Cooling tower function: the waste heat generated in the industrial production process is generally taken away by cooling water. The function of the cooling tower is to exchange the cooling water with the waste heat with the air in the tower, so that the waste heat is transferred to the air and dissipated into the atmosphere. For example, in a thermal power plant, the boiler heats water into high-temperature and high-pressure steam, and drives the steam turbine to do work to make the generator generate electricity. Return to the boiler for recycling. In this process, the waste heat of the exhausted steam is transferred to the cooling water, which increases the temperature of the water, and the cooling water, which carries the waste heat, transfers the heat to the air in the cooling tower, and is discharged into the atmospheric environment from the air duct.
Application scope of cooling tower: Mainly used in air-conditioning cooling system, refrigeration series, injection molding, tanning, foaming, power generation, steam turbine, aluminum profile processing, air compressor, industrial water cooling and other fields. Plastic chemical industry.
4. Sieve plate extraction column
Features of sieve plate
Extraction Tower: large processing capacity, simple structure, low cost, widely used in chemical production process. The flow structure of the liquid-liquid two-phase in the column has an important influence on the mass transfer efficiency, and the flow structure of the continuous phase is closely related to the structure of the column internals.
5. Packed extraction column
Working principle: The structure of the packed extraction column is basically the same as that of the packed column for rectification or absorption. Suitable packing is installed in the column. The light liquid phase enters from the bottom of the column and is discharged from the top of the column; the heavy liquid phase enters from the top of the column and is excluded from the bottom of the column. . During the extraction operation, the continuous phase fills the entire column, and the dispersed phase is dispersed into droplets by the distributor and enters the packing layer, and is in contact with the continuous liquid phase for mass transfer.
6. Reciprocating sieve plate extraction column
Working principle: Reciprocating sieve plate extraction tower is also called vibrating sieve plate tower. The tower is equipped with extraction equipment with a central axis of reciprocating vibration with many sieve plates. The central axis drives the plate string to reciprocate in the vertical direction in the column through the driving device at the top of the column, so as to remove the countercurrent flow of the two liquid phases in the column. Agitation and dispersion. The amplitude and frequency of the reciprocating motion of the plate string can be adjusted. Because the reciprocating sieve plate extraction tower has the advantages of large processing capacity, high efficiency, large operation flexibility and simple structure, it is widely used in pharmaceutical, petrochemical, hydrometallurgy and wastewater treatment industries. .
7. Rotary sieve plate extraction column
Working principle: The rotary disc extraction tower is a tower type extraction equipment with mechanical stirring. It consists of three parts: the upper clarification section, the mixing section, and the lower clarification section. The mixing section is in the shape of a cylinder, the interior is divided into a series of extraction chambers by static ring baffles, and a fixed turntable is located in the middle of the two static ring baffles, and rotates together with the stirring shaft. When working, the heavy phase (aqueous phase) and the light phase (organic phase) enter from the top and bottom of the tower respectively, and are in countercurrent contact in the tower. Under the agitation of the fixed turntable, the dispersed phase forms small droplets, which increases the mass transfer area. After the extraction process is completed, the light phase and the heavy phase flow out from the outlet at the top and bottom of the column, respectively.
8. F1 float tower
Features: Large production capacity, stable tray efficiency, large operation flexibility, low cost, convenient maintenance and cleaning, so it is widely used.
Working principle: It is usually used to make vapor (or gas) in close contact with liquid to promote mass transfer between them. The tower is equipped with multi-layer horizontal trays, on which there are several short tubes for steam (or gas) to pass through, which are covered with bubble caps with tooth gaps or small grooves on the bottom edge, and are equipped with overflow pipes. During operation, the liquid enters continuously from the upper part of the tower, descends plate by plate through the overflow pipe, and accumulates a liquid layer on each plate to form a liquid seal; The gaps or small grooves are dispersed into small bubbles, which fully contact the liquid, pass through the liquid layer to reach the liquid level, and then rise to the upper tray. If the short pipe is installed in the tower, it is called internal overflow; if it is installed outside the tower, it is called external overflow. Bubble cap columns are widely used in rectification and gas absorption. Bubble cap column has high operating flexibility, and the tray is not easy to block, but the structure is complex, the cost is high, the liquid layer on the plate is thick, the pressure drop on the tray is large, and the production capacity and tray efficiency are low.
10. Turbulence ball tower dust collector
Principle: A certain amount of polyethylene spherical packing is discharged into the tower. When the gas velocity reaches a certain value, the small balls are suspended and violently toss and rotate and collide with each other to achieve the effect of mass transfer and dust removal.
Features: It overcomes the shortcomings of traditional towers that are easy to scale, easy to block, low in desulfurization efficiency, unstable in operation, and high in operating costs.
11. Scrubber
Introduction: The scrubber is a new type of gas purification treatment equipment. It is improved on the basis of the floating packing layer gas purifier, and is widely used in the pretreatment of industrial waste gas purification, dust removal, etc., and the purification effect is very good. For the coal gasification process, gas scrubbing is unavoidable, and this unit operation is used regardless of the coal gasification technology. Because its working principle is similar to the washing process, it is called a
Washing Tower.
Features:
1) The water-washing waste gas treatment system is cheap and the treatment method is simple;
2) The vertical structure is most suitable for economical space installation;
3) Applicable to gaseous and liquid pollution sources;
4) Deal with a single source of pollution;
5) Suitable for medium and low air volume;
12. Fractionation column
Principle: In a limited space, the heat exchange area of the liquid phase mixture should be increased as much as possible. Generally, the mixture used for rectification and fractionation is an organic azeotrope. The azeotrope is first heated from the
Reactor and rises to the fractionation section. The boiling point The low boiling point continues to rise, because the temperature of the top of the tower is the same as that of the low boiling point material after the heat transfer by the low boiling point material, so the low boiling point material is fractionated, and the higher boiling point material does not reach the corresponding boiling point, so it will be cooled and refluxed In the reactor or the lower part of the fractionation column, after the low boilers are completely distilled, the higher boilers are successively fractionated, and then the high boilers are distilled off, and finally the bottom of the reactor is the residue.
April 26, 2022
