PP spray towers are widely used in chemical industry, electroplating, pickling, electronics, mechanical processing and other industrial waste gas treatment scenarios. They play an important role in acid and alkali waste gas absorption, dust pretreatment and waste gas cooling. In order to ensure the stable operation of the equipment, operators should start, inspect and maintain according to the prescribed procedures.

1. Preparations before starting the equipment

1. Check the water level: Add water to the circulating water tank or liquid distribution tank to make the liquid level reach the specified position of the equipment, and confirm that the water replenishment valve, overflow port and sewage outlet are in normal condition.

2. Check the connection parts: Check whether the circulating water pump, fan, pipeline, flange and bolt are loose. If any abnormality is found, tighten or handle it in time.

3. Check the spray system: Confirm that the spray pipes, nozzles and liquid distributors are not blocked, and there is enough working fluid in the spray tank or circulating water tank.

4. Prepare absorption liquid: add corresponding chemicals according to the properties of exhaust gas. When treating acidic waste gas, alkaline agents can be added according to process requirements and thoroughly stirred to dissolve.

5. Check the electrical system: Check the fan, spray pump, electric control box, liquid level switch and emergency stop device, and then turn on the power supply of the equipment after confirming that there are no abnormalities.

2. Start-up process of PP spray tower

1. Start the circulating water pump first and observe whether the nozzles can spray evenly.

2. Check the circulating fluid flow, liquid level and pipeline for leaks.

3. After confirming that the sprinkler system is operating normally, start the exhaust fan.

4. Observe the tower pressure difference, air volume, spray status and equipment vibration.

5. According to the waste gas treatment requirements, regularly detect the pH value and chemical concentration of the circulating fluid, and replenish the chemicals in a timely manner.

3. Working process of the filler layer

The bottom of the PP spray tower is usually equipped with a filler support plate, and the filler is evenly laid on the top of the support plate. A pressure plate can be installed on the top of the packing layer to prevent the packing from moving due to the influence of rising airflow.

The spray liquid is evenly sprayed from above the packing layer through the liquid distributor and flows downward along the packing surface. The waste gas enters the tower body through the air inlet, passes through the packing layer under the action of the air flow distribution device, and forms full contact with the absorption liquid.

The gas-liquid two-phase mass transfer occurs on the surface of the packing, so that the acidic, alkaline or water-soluble pollutants in the exhaust gas are captured by the absorption liquid. The larger the filler surface area and the more even the liquid distribution, the better the gas-liquid contact effect is usually.

4. Avoid the wall flow phenomenon in the packing layer

When the absorption liquid flows downward along the packing layer, part of the liquid may flow concentrated along the tower wall, forming a wall flow phenomenon. Wall flow will lead to uneven distribution of gas and liquid inside the packing layer, thereby reducing mass transfer efficiency and waste gas treatment effect.

When the height of the packing layer is high, the packing layer can be set up in sections, and a liquid redistribution device can be installed between different packing layers to redistribute the circulating liquid evenly and then enter the lower packing, thus improving the gas-liquid contact state.

5. Inspection items during equipment operation

1. Regularly check whether the nozzles are clogged, and clean them in time if uneven spraying is found.

2. Check the circulating water pump and fan for abnormal noise, vibration or abnormal temperature rise.

3. Check the water tank level to prevent the water pump from running idling due to lack of water.

4. Check the pH value, color and sediment condition of the circulating fluid, and refill, drain or replace it if necessary.

5. Check the filler layer, demister layer and air inlet and outlet ducts for blockage.

6. Check the tower body, flanges, valves and pipe connections for leaks.

6. Equipment shutdown process

1. Stop the production equipment or close the exhaust gas source.

2. Keep the spray system and fan running for a period of time so that the residual waste gas in the pipeline and tower can be processed.

3. Turn off the fan first and then the circulating water pump.

4. When shutting down for a long time, the circulating fluid should be drained and the water tank, nozzles, fillers and pipelines should be cleaned.

7. Usage characteristics of PP spray tower

PP spray tower has the characteristics of acid and alkali resistance, corrosion resistance, simple structure, easy operation and relatively low operation and maintenance costs. The treatment effect of the equipment is not only related to the quality, specifications and selection of the equipment, but also closely related to the actual operating methods, spray fluid management and daily maintenance.

Standardized operations, regular inspections and timely maintenance can help reduce problems such as nozzle clogging, filler scaling, water pump idling and fan corrosion, and extend the service life of the equipment.

When preparing and adding chemical agents such as sodium hydroxide, you should wear protective gloves, goggles and other personal protective equipment, and control the agent concentration in accordance with the equipment and process requirements to avoid direct contact with the skin or eyes.