Hydroelectric power plant, that is, hydroelectric power plant, is the use of hydroelectric resources to generate electricity; Compared with power plants that generate electricity by burning fossil fuels such as coal, oil and natural gas, they have advantages and disadvantages such as having less impact on the environment, generating efficiency of up to 90% or more, low power generation cost, fast power generation start, power generation can be completed within a few minutes, easy adjustment, and the lowest cost per unit of output power. To this end, China is vigorously developing hydropower resources. The construction of major hydropower projects is also developing rapidly.

It is understood that the problem of moisture and dew is a problem that has plagued major hydroelectric power plants for many years; Due to the influence of topography and other factors, many proposed, under construction and already built large-scale hydropower stations have chosen the form of underground powerhouse. Because hydropower stations are generally deeply buried underground workshops, they are not exposed to sunlight, and the surface of the envelope structure is relatively wet, and the relative humidity of the air is often larger. Especially in turbine layer and volute layer of hydropower station, the relative humidity even reaches more than 90%, and condensation often occurs in the plant.

Wet underground space not only affects the service life of mechanical and electrical equipment, but also adversely affects the health of staff. When some large hydroelectric generator equipment is running, the surface of the turbine main shaft is easy to produce water beads, which will enter the water guide bearing along the cover of the oil basin, bringing hidden dangers to the safe operation of the generator set. There are many pipelines and electrical equipment in the pump room, and condensation occurs on the surface of the pipelines and electrical equipment, forming water droplets, which greatly speeds up the damage rate of the sealing materials, metal parts and electrical components of the pump, causing safety hazards to the stable operation of the pump.

Every year from April to October, most of the hydropower plant main workshop wet, dew is very serious, the ground, wall, pipe surface constantly dew outflow, leading to the generator stator rod end rust, water supply room electrical components misoperation, affecting the normal production of the system, this phenomenon is widespread in hydropower plants. In the past, some large hydroelectric power plants in order to solve such problems, most of the domestic and foreign use in the supply and drainage pipe wrapped insulation material layer method, but because the temperature difference between the air and the cold object is too large, and the water pipe and the coating for a long time contact, eventually resulting in the coating surface temperature close to the cold object (cold water) temperature, condensation still exists;

Another method is to use the inner layer to wrap the thermal insulation material, the outer layer to wrap the organic glass steel or aluminum alloy plate, so although the outer surface condensation has been reduced, but because no matter how sealed, can not completely discharge the wet air between the surface of the cold object and the thermal insulation layer and the entry of the external wet air, so after a period of time, open the thermal insulation layer, most of the water pipe surface has been corroded. The condensation problem is transformed into a rust problem, so it can be seen from the practice of major power plants: the use of coating or thermal insulation is not ideal, can not solve the fundamental problem.

In response to this situation, through the continuous exploration and exploration of hydropower industry technicians found that the most simple and effective way to solve the problem of moisture and dew is to use dehumidifier. Dehumidifier is the most professional moisture-proof dehumidification equipment at present, which can quickly extract excess water in the air, control the moisture content in the air within the ideal range, and can carry out a full range of indirect dehumidification for various items or equipment, leaving no dead corners.