PP defogger

PP defogger

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The PP defogger is mainly composed of fixed devices such as waveform blades, plates, and clamps. During wet desulfurization and absorption tower operation, "fog" with a particle size of 10-60 microns is easily generated. "Fog" not only contains moisture, but also dissolves sulfuric acid, sulfate, sulfur dioxide, etc., which also causes pollution and severe corrosion of fans, heat exchangers, and flues. Therefore, wet desulfurization process requires defogging of absorption equipment, and the purified gas must be defogged before leaving the absorption tower.

Structural characteristics of PP defogger

1. The blade shape is like a sine curve, with a smooth surface that is easy to wash and reduces the risk of blockage;

2. The blades are designed with hooks and ribs, which can intercept very small droplets of fog;

3. The defogger is easy to maintain;

4. Drainage system design，Drain the intercepted slurry. Main design parameters of PP defogger

(1) The high or low flow velocity of the flue gas passing through the section of the defogger is not conducive to the normal operation of the defogger. Excessive flow velocity of the flue gas can easily cause secondary water carryover, thereby reducing the defogging efficiency. At the same time, high flow velocity leads to high system resistance and energy consumption. The low flow velocity through the section of the defogger is not conducive to gas-liquid separation and also not conducive to improving defogging efficiency. In addition, if the designed flow rate is low, the cross-sectional size of the absorption tower will increase, and the investment will also increase accordingly. The design flue gas flow rate should be close to the critical flow rate.

(2) The spacing between the blades of a defogger has a significant impact on its defogging efficiency. The defogging efficiency decreases with the increase of blade spacing. The increase in the distance between the plates leads to an increase in the flow area of particles in the channel, and at the same time, the change in the velocity direction of the airflow tends to be gentle, resulting in the particles' followability to the airflowIt is easy to flow out of the blade channel with the airflow without being trapped, resulting in a decrease in defogging efficiency.

(3) The increase in the number of stages of the defogger increases the defogging efficiency, and the pressure loss also increases accordingly. The design of a defogger should aim to improve defogging efficiency and reduce resistance losses. Therefore, simply pursuing defogging efficiency and increasing the number of stages ignores the increase in airflow resistance loss, resulting in a significant increase in energy loss. The current WFGD system adopts a two-stage defogging system.

(4) The flushing water pressure of the defogger is generally determined based on factors such as the characteristics of the flushing nozzle and the distance between the nozzle and the defogger. When the flushing water pressure is low, the flushing effect is poor. If the flushing water pressure is too high, it is easy to increase the water carried by the flue gas and reduce the service life of the blades.

(5) The selection of the flushing water volume for the defogger should not only meet the requirements of the defogger itself, but also consider the requirements of the system water balance. Under some conditions, a large amount of water should be used for short-term flushing, and sometimes a small amount of water should be used for long-term flushing. The specific flushing water volume needs to be determined by the operating conditions. Generally, the instantaneous flushing water consumption on the defogger section is about 1-4m3/h.

(6) Flushing coverage refers to the degree to which the flushing water covers the cross-section of the defogger. In the formula: - flushing coverage rate,; N - the number of nozzles, pieces; H - the vertical distance between the flushing nozzle and the surface of the defogger, m; a - the spray diffusion angle, A - the effective flow area of the defogger, m2; depending on different operating conditions, the flushing coverage rate can generally be selected between 100% and 300%.

(7) The flushing cycle of the defogger refers to the time interval between each flushing of the defogger. PP Mist Eliminator Application Mist eliminator is used to separate liquid droplets carried by gas in a separation tower to ensure mass transfer efficiency, reduce valuable material loss, andThe operation of the compressor behind the tower is usually carried out by installing a defogger at the top of the tower.