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The absorbed mixture enters from the bottom of the tower, while the absorbent liquid is sprayed down from the top; gas-liquid mass transfer occurs between the liquid and gas on the surface of the packing. A packed tower is a mass transfer device that uses the packing inside the tower as the contact element between the gas and liquid phases. The tower body of a packed tower is a vertical cylinder, with a packing support plate at its bottom; the packing is placed on this support plate either in a random manner or in an organized pattern. A packing plate is installed above the packing to prevent it from being blown by upward air currents. The liquid is sprayed from the top of the tower through a liquid distributor onto the packing, and flows down along the surface of the packing. Gas is fed in from the bottom of the tower; after being distributed by a gas distribution device (which is generally not used in towers with small diameters), it flows counter-currently to the liquid through the gaps in the packing layer. On the surface of the packing, the gas and liquid phases come into close contact, enabling mass transfer to occur. A packed tower is a type of continuous-contact gas-liquid mass transfer device, in which the composition of the two phases changes continuously along the height of the tower. Under normal operating conditions, the gas phase acts as the continuous phase, while the liquid phase is the dispersed phase. As the liquid flows downward through the packing layer, it tends to concentrate toward the tower wall, resulting in an increasing flow rate of liquid near the wall; this phenomenon is known as wall flow. The wall flow effect causes uneven distribution of the gas-liquid phases in the packing layer, thereby reducing the mass transfer efficiency. Therefore, when the packing layer is high, it needs to be segmented, with a redistribution device installed in between. The liquid redistribution device consists of a liquid collector and a liquid redistributor. The liquid that flows down from the upper packing is collected by the liquid collector and then sent to the liquid redistributor, where it is redistributed before being sprayed onto the lower packing. Packed towers have advantages such as high production capacity, high separation efficiency, low pressure drop, low liquid holdup, and great operational flexibility. Packed towers also have some drawbacks, such as high costs for the packing; they are unable to effectively wet the surface of the packing when the liquid load is low, which reduces the mass transfer efficiency; they cannot be used directly with materials that contain suspended solids or are prone to polymerization; and they are not suitable for complex distillation processes involving side feed and withdrawal. Performance features: A solvent recovery device that utilizes packing inside a tower to increase the contact area between the absorbent (vegetable oil or mineral oil) and the exhaust gas. A gas-liquid exchange device that operates through gas-liquid contact. A packed tower consists of packing, internal components of the tower, and the cylinder. Packing is divided into two main categories: structured packing and loose packing. The internal components of the tower include various types of liquid distribution devices, packing fixing or compressing devices, packing support devices, liquid collection and redistribution devices, as well as gas distribution devices. Compared with plate towers, the new type of packed tower exhibits the following advantages: high production capacity, high separation efficiency, low pressure drop, large operational flexibility, and low liquid holdup.