Working principle of spray absorption tower

As one of the flue gas desulfurization equipment, the spray absorption tower has been widely used in various industries and production fields such as coal, oil and gas. So, how does it work?

1. flue gas into the tower body

The flue gas of the spray absorption tower enters from the bottom. After passing through the air inlet, it first enters a preprocessor to pretreat the impurities and pollutants in the flue gas to ensure that it is better absorbed in the tower body.

2. flue gas contact with spray liquid

The flue gas then enters the center of the tower and comes into contact with the spray liquid sprayed from above. After the spray liquid is atomized by the nozzle, a large area of contact interface is formed with the flue gas, and impurities such as sulfur dioxide and oxygen in the flue gas will be absorbed and oxidized.

3. reactions produce compounds

When the spray liquid is in contact with the flue gas, a series of reactions will occur, the most important of which is the sulfation reaction. Sulfur dioxide in the presence of water molecules, Mr. into sulfuric acid, and then combined with oxygen in the air, sulfuric acid.

4. liquid dripping

As the flue gas is gradually purified, the purified flue gas will rise to the top of the tower and be discharged through the exhaust port. The spray liquid will form a so-called "liquid pool", in which the liquid accumulates for a period of time, due to gravity, begins to drip and returns to the atomization system, and is recycled again.

5. management and maintenance of equipment

The management and maintenance of spray absorption tower is very important. Due to the use of equipment in the process, will produce a large number of acidic wastewater and gypsum and other by-products, if not properly treated, will bring serious harm to the environment and health. Therefore, the operator needs to regularly clean the liquid pool and system, and at the same time carry out regular maintenance and inspection of the equipment to ensure the normal operation and purification effect of the equipment.

In general, the working principle of the spray absorption tower is to use the contact reaction between the spray liquid and the flue gas to absorb and oxidize the harmful impurities and pollutants in the flue gas, thereby improving the quality of the air.

For the use of spray absorption tower, we need to maintain the management and maintenance of the equipment, strictly abide by the operating procedures and environmental protection laws and regulations, and protect the health of employees and the beauty of the environment.

Introduction of spray absorption tower structure

Equipment composition: spray absorption system adopts vertical cylinder design, which is composed of packing, spray device, demisting device, spray liquid circulating pump and absorption tower.

(1) Packing

The packing is mainly used as a device to increase the liquid-gas contact area, which is arranged at the bottom of the spray layer of the absorption tower, and the device can greatly improve the absorption efficiency of the gas. In addition, the tray carrying the ring body can evenly distribute the exhaust gas in the main spray area, so that the exhaust gas and the absorbing liquid or washing liquid are fully contacted in the liquid film area on the tray. The structure of the tray is a PP mesh porous plate, which is more convenient for gas and liquid medicine to pass through, and it is horizontally resting on the structure supported by the tray.

(2) Spray device

The internal spray system of the absorption tower is a network system composed of distribution main pipe, branch pipe and nozzle, equipped with a circulating pump. A high-pressure spiral nozzle is installed on the spray layer. The nozzle has the advantages of large spray angle, uniform spray, and not easy to be blocked. Its function is to atomize the spray liquid. The spray liquid is transported to the nozzle by the absorption tower recirculation pump and sprayed into the exhaust gas. The spray system can make the liquid evenly distributed in the absorption tower, and the flow through each spray layer is equal.

(3) Defogging device

The demister adopts high-efficiency demisting plastic net cotton to separate the droplets carried by the treated clean gas. The demister of the absorption tower is arranged on the upper part of the last spray assembly on the top of the absorption tower. When the exhaust gas passes through the circulating liquid spray layer and then continuously flows through the demister, the droplets remain on the baffle due to inertia. Since the retained droplets also contain solid matter, there is a danger of the baffle structure, which requires regular cleaning.

(4) Spray liquid circulating pump

The recirculation pump of the absorption tower is installed in the chemical tank beside the absorption tower to recycle the spray liquid in the absorption tower. Adopt special vertical acid-base centrifugal pump, including pump casing, impeller, shaft, guide bearing, import, seal box, shaft seal, basic frame and motor, etc. The working principle is that the centrifugal force generated when the impeller rotates at high speed enables the liquid to obtain energy, that is, after the fluid passes through the impeller, the pressure energy and kinetic energy can be increased, so that it can be transported to a high place or a distance. At the same time, a negative pressure is formed at the inlet of the pump, so that the fluid can be continuously sucked. The pump head is made of corrosion resistant material. After the circulation system is used for a period of time, the circulating liquid wastewater is finally discharged into the wastewater treatment tank.

(5) Spray absorption tower

The tower body is made of PP material. In the design of the spray tower shell, considering that its working environment is quite harsh, it works under acidic corrosion for a long time, and also bears the pressure of the tower body itself and the solution pressure, as well as the wind pressure during work, it is required to have good corrosion resistance and maintain high tensile and compressive strength. Therefore, the spray tower body is produced by mechanical welding process, with high strength, credible quality and good performance.

Main process parameters of spray absorption tower