The water curtain spray booth uses a flowing curtain-like water layer to collect and take away paint mist. The curtain-like water layer is generally set directly in front of the air stream containing paint mist. In the painting room with horizontal air supply, the water curtain hangs like a curtain on the wall directly in front of the operator. The water curtain in the large up and down air suction painting room is arranged at the bottom of the room, and placed on the slope. When the air flow is rushing to the water curtain, the paint particles impact the water drop and are left behind. The curtain is maintained by the special circulating water pump, and the water volume is adjusted by the regulating valve to control the integrity of the water curtain shape. The wall of the water curtain spray booth is not easy to be polluted, the effect of treating paint mist is better, and the structure is simple. However, as the paint mist is collected by water, the exhaust gas containing paint mist is transformed into wastewater containing paint mist. As a result, secondary pollution is formed, so wastewater must be re-treated. In addition, due to the use of large area water curtain, the evaporation area of water is large, and the indoor air humidity is large, which may affect the decorative quality of the spray coating line.
Water is atomized and sprayed to the air containing paint mist by water pump nozzle. In addition, due to the use of a large-area water curtain, the evaporation area of water is large, and the indoor air humidity is high, which may affect the decoration quality of the spray coating. The amount of water particles (that is, the amount of water) and the atomization effect of the water directly affect the paint mist collection efficiency. The flow rate of air containing paint mist will also affect the collection efficiency of paint mist.
Ordinary water wash paint booths belong to the older spray booths. The wall of the spray booth is easy to be polluted and its nozzle is easy to be blocked. The effect of paint mist treatment is poor, and it has been gradually replaced by other types of wet spray booth. The new spray booth is mostly combined type. For example, the water curtain-washing spray booth, the combination methods are roughly divided into the following three types:
1. Multi-stage water curtain or multi-stage water wash paint booth.
2. Water curtain and washing multi-stage combined spray booth.
3. Water curtain, water washing and curved air duct spray booth.
The combination principle is as follows:
1. Increase the paint mist treatment time. From the paint mist escaping from the workpiece to the fan discharge, it should be treated many times to ensure the full treatment.
2. Increase the contact between water particles and paint mist. In order to improve the efficiency of paint mist treatment, it is necessary to make the paint mist fully condense with each other, or make the paint mist adhere to the liquid film and bubble, or generate dew drop condensation with particles as the core.
3. Increase the chance of throwing paint particles to the wall or water surface of treatment chamber under gravity, inertia force and centrifugal force, so that the paint particles can be better collected and treated.