Packed tower structure

Packed towers are filled with different packing materials based on different efficiencies, including bulk packing and structured packing. The internal parts of the tower mainly include packing supports, liquid distributors, liquid redistributors, liquid collectors, foam breakers, etc.

Structures of structured packing towers and random packing towers are different

This post was last edited by lxq700918 on 2009-8-4 13:12. Similar posts have been fully discussed in the forum. I believe it will be helpful to you. Links are provided below for reference. 1. http://bbs.hcbbs.com/thread-187402-1-1.html Packed tower structure diagram 2. http://bbs.hcbbs.com/viewthread.php?tid=52068 Structural principles of packed tower

Packed towers use packing as mass transfer elements. Its internal components are mainly arranged around the packing and its working conditions, including the packing and supporting structure, packing pressure plate, spray device, and liquid redistribution device.

A packed tower is a mass transfer device that uses the packing in the tower as a contact component between the gas and liquid phases. The tower body of the packed tower is a vertical cylinder (as shown in the picture on the right), with a packing support plate installed at the bottom, and the packing is placed on the support plate in a random pile or in a complete pile. A packing pressure plate is installed above the packing to prevent it from being blown by the rising airflow. The liquid is sprayed from the top of the tower onto the packing through the liquid distributor and flows down along the surface of the packing. The gas is fed from the bottom of the tower, and after being distributed through the gas distribution device (small diameter towers generally do not have a gas distribution device), it continuously passes through the gaps in the packing layer in countercurrent with the liquid. On the surface of the packing, the gas and liquid phases are in close contact for mass transfer. The packed tower is a continuous contact gas-liquid mass transfer equipment. The two-phase composition changes continuously along the height of the tower. Under normal operating conditions, the gas phase is the continuous phase and the liquid phase is the dispersed phase. When the liquid flows downward along the packing layer, it has a tendency to gradually concentrate toward the tower wall, causing the liquid flow rate near the tower wall to gradually increase. This phenomenon is called wall flow. The wall flow effect causes the gas and liquid phases to be unevenly distributed in the packing layer, thus reducing the mass transfer efficiency. Therefore, when the filler layer is high, it needs to be segmented and a redistribution device is installed in the middle. The liquid redistribution device consists of two parts: a liquid collector and a liquid redistributor. The liquid flowing down from the upper packing is collected by the liquid collector and sent to the liquid redistributor. After redistribution, it is sprayed onto the lower packing. The packed tower has the advantages of large production capacity, high separation efficiency, small pressure drop, small liquid holding capacity, and large operating flexibility. Packed towers also have some shortcomings, such as the high cost of packing ； When the liquid load is small, the packing surface cannot be effectively wetted, resulting in reduced mass transfer efficiency. ； It cannot be used directly on materials with suspended solids or easily polymerized materials. ； It is not suitable for complex distillation such as side feed and discharge. 　 The tower internals mainly include the following parts:: Liquid distribution device, packing fastening device, packing support device, liquid collection and redistribution and inlet and outlet device, gas feeding and distribution device, defoaming device

Nowadays, composite towers are used, with float valves in the lower tower and packing in the upper tower.

Due to the more stringent processing conditions of raw materials and the increase in negative reactions, the form of the heat and mass transfer carriers in the tower - trays or packing groups is more flexible and more in line with production needs. Float valve trays are often used in the stripping section and the lower part of the rectifying section. Multi-stage packings are mostly used in the middle and upper parts of the rectifying section, and mostly structured packings are used. The lower part of the packing is a support plate, and of course there is a liquid collection tank with a rising air hole. The upper part has a secondary liquid separation tank, a primary liquid separation tank, and a liquid separation pipe. Modern high-efficiency packing is closer to the theoretical plate. Mass and heat transfer are very good. However, there is still a lot of work to be done to truly maximize the effectiveness of these fillers.

This post was last edited by shan1949 on 2012-4-10 16:17 I don’t know how to design a 4-meter-diameter packing grid? Please tell me. . . QQ475640975