The horizontal PP scrubber, named for its structural form and gas scrubbing process, is a common industrial waste gas treatment equipment. This equipment is optimized and improved on the basis of the packing layer gas purification device. It can be used for industrial waste gas purification, dust pretreatment and partial organic waste gas treatment.

The horizontal PP scrubber has the characteristics of compact structure, corrosion resistance, easy installation and maintenance, etc. It can be used as pretreatment equipment for subsequent exhaust gas treatment systems to reduce the impact of particulate matter, water-soluble pollutants and some corrosive components on back-end equipment.

1. Suitable for waste gas pretreatment

In the process of odor gas treatment, the collected waste gas often contains paint mist, particulate matter, water-soluble organic matter and other components. These substances may affect the purification efficiency, operating energy consumption and service life of subsequent treatment facilities.

The horizontal PP scrubber can be used as a pre-treatment device to spray, reduce dust, absorb and cool down the exhaust gas, reducing unfavorable components from entering the subsequent treatment system and making the overall treatment system more stable.

2. It has the functions of cooling and adjusting humidity

When the exhaust gas inlet temperature is higher than the allowable inlet temperature of subsequent equipment, the scrubber can be used for cooling treatment. For example, before some high-temperature exhaust gas or gas after combustion treatment enters the subsequent purification process, the gas temperature can be reduced through a spray system.

The water washing process can also increase the humidity of the exhaust gas. For biological deodorization systems that need to maintain certain humidity conditions, the spray-humidified gas helps maintain a humid environment inside the subsequent treatment device.

3. Principle of gas-liquid contact and absorption

A spray layer, a packing layer and a defogging layer are usually installed inside the horizontal PP scrubber. After the exhaust gas enters the tower, it fully contacts the fine droplets produced by the spray system and the absorption liquid on the surface of the filler.

The filler can disperse the air flow and liquid flow, increase the air-liquid contact area, and cause the pollutants to dissolve, absorb or chemically react in the absorption liquid. The empty tower cross-section gas velocity, packing height, gas residence time and spray density are important design parameters that affect the treatment effect of the scrubber.

4. Acid-base waste gas treatment process

Industrial acid-base waste gas enters the scrubber under the action of a fan. The sprinkler head sprays the absorption liquid evenly on the filler layer, and the exhaust gas and the absorption liquid fully contact and react on the filler surface.

For gases such as HCl, NO₂, NH₃ that are easily soluble in water or can react with liquid chemicals, corresponding absorption liquids can be prepared according to the properties of the pollutants. After the pollutants are absorbed or transformed, the content of harmful components in the gas is reduced.

The purified gas may contain a small amount of water mist, so it usually needs to pass through a demister layer for gas-liquid separation to reduce droplets from entering subsequent equipment or discharge pipes with the air flow. The absorption fluid can be recycled according to actual operating conditions and replenished or replaced regularly.

5. Structural composition of the horizontal PP scrubber

The horizontal scrubber can be made of PP, FRP or stainless steel. The specific material should be determined according to the exhaust gas composition, temperature, corrosiveness and use environment.

1. Tower body: It adopts horizontal structure to facilitate installation in height-restricted sites.

2. Circulating water tank: It can be set up integrally with the tower or independently. The capacity is determined according to the spray volume, number of cycles and operating time.

3. Spray system: It consists of circulating water pump, spray pipeline and nozzle, which is used to evenly spray the absorption liquid to the filling area.

4. Filling layer: One or more layers of filling should be set according to the exhaust gas treatment requirements. The height of the single layer should be designed based on the air volume, resistance and absorption efficiency.

5. Demist layer: Set at the front end of the gas outlet, it is used to separate and purify liquid droplets entrained in the gas.

6. Maintenance and drainage device: convenient for daily inspection, cleaning, water replenishment, sewage discharge and filling replacement.

6. Parameters that need attention during design

1. Exhaust gas treatment air volume, inlet concentration and pollutant composition.

2. Exhaust gas temperature, humidity and corrosiveness.

3. Gas flow velocity and gas residence time in the tower.

4. Spray fluid circulation volume, nozzle arrangement and liquid-gas ratio.

5. Filling type, filling height and system operating resistance.

6. Type of absorption liquid, concentration of chemicals and method of sewage discharge and rehydration.

7. Inlet air temperature and humidity requirements for subsequent processing equipment.

7. Equipment application characteristics

The horizontal PP scrubber is suitable for working conditions where the site height is limited, the exhaust gas contains dust, water-soluble pollutants, acid and alkali components, or where cooling and humidification are required. The pretreated gas can enter activated carbon adsorption, biological deodorization, photooxygen catalysis or other subsequent treatment equipment.

The above are the main design features of the horizontal PP scrubber device. Actual equipment specifications and system configuration should be designed based on exhaust air volume, pollutant concentration, temperature and emission requirements.