Wet electrostatic precipitator manufacturerTechnical Principle

Wet electrostatic precipitatorCompared to dryElectrostatic precipitatorThe working principle is the same, which is to deliver DC negative high voltage to the electric field space. Through gas ionization in the space, dust particles and mist droplets in the flue gas are charged and move to the dust collection electrode (collector electrode) under the action of electric field force, and are collected on the surface of the dust collection electrode. Dry type electricitydust collectorThe collected dust is shaken into the ash hopper using vibration cleaning method, while the wet electrostatic precipitator collects mist droplets and particles from the flue gas, forms overflow on the surface of the dust collector, and flushes the dust into the ash hopper (water ash hopper).

The major difference between wet electrostatic precipitators and dry electrostatic precipitators lies in the working fluid of the flue gas. Dry electrostatic precipitators produce dry flue gas, which has a higher temperature and is essentially free of fog droplets. The wet electrostatic precipitator produces wet saturated flue gas, which has a lower temperature and contains a large amount of mist droplets.

Wet electrostatic precipitators are usually installed after wet desulfurization equipment. After desulfurization, a large number of water droplets are carried in the saturated flue gas and captured when passing through a high-voltage electric field, which can reduce the probability of gypsum rain formation. At the same time, it has a good effect on collecting fine particulate matter such as PM2.5 and acid mist, and the smoke emission concentration can reach ≤ 10 milligrams per cubic meter.

The wet electrostatic precipitator developed adopts a new anti-corrosion material for the anode plate, which does not require continuous injection of alkaline water. The system structure is simple and has achieved five technological innovations:

1. The high-voltage power supply adopts a cross current source and spark control device, which can effectively avoid the phenomenon of flashover and arc pulling, ensuring stable operation of the electric field.

2. During operation, there is no need to continuously spray alkaline water. Instead, the fog droplets in the flue gas are collected by the electric field area, forming an overflow in the dust collection tube bundle to achieve the purpose of self cleaning.

3. Adopting a new type of corrosion-resistant composite material as the dust collection plate, with a modular structure and honeycomb layout, can effectively utilize space and achieve uniform flow field distribution. Corrosion resistance, stable discharge strength, keeping equipment voltage and current at high parameters, thereby ensuring good dust removal effect.

4. The use of new corrosion-resistant composite materials enables the flexible arrangement of the electrostatic precipitator (mist) structure, which can adapt to the current complex renovation site. It can be separately arranged at the outlet of the desulfurization tower's clean gas flue (such as Huangtai Power Plant), at the top of the desulfurization tower, or separately arranged in an open space where the power plant site conditions permit.

5. Wet electrostatic precipitator is one of the advanced PM2.5 control technologies currently available, which can achieve the following performance indicators:

*Low power consumption (less than 300 kW for a 300000 kW unit) and low resistance (less than 350 Pa)

*The removal efficiency of fine particles is high. The PM2.5 emission concentration is less than 1.5 milligrams per cubic meter.

*The removal efficiency of aerosols and sulfur trioxide is greater than 60%.

*The removal efficiency of heavy metal mercury is about 40%.

*The droplet removal efficiency is greater than 85%.