Hybrid Cooling Tower

A hybrid cooling tower is a cooling system that leverages wet and dry cooling technologies to reduce both the plume volumes and the consumption of water, minimizing the impact on the environment.
Air enters from both the wet and dry sections of the tower. The air coming from the lower sections passes through the wet section before reaching the upper dry section. The air from the wet and dry sections rises and mixes above the fan, resulting in little or no visible plume.

● Plume
Visible plume is essentially pure water vapor discharged from cooling towers during operation. It is visible when the moist heated air mass leaving the tower is cooled below its dew point. Visible plume is most prevalent during winter periods, when warmer moist air mixes with colder ambient air. Visible plume discharged from a cooling tower is not an air pollutant. Through plume, cooling towers add heat and moisture to the surrounding environment.
In hybrid cooling towers, the dried and warmed air flow produced within the dry section tube bundles mixes with the dried out saturated air from the wet section to reduce plume formation.
The mixed and unsaturated air leaving the hybrid tower leverages the combined cooling effects of both wet and dry sections, thus even if cooled by surrounding ambient, air will not become supersaturated, and no visible fog will occur.
Hybrid cooling towers are specifically designed to avoid visible plume in cold, humid, ambient conditions and when local constraints require this technology, such as at airports or residential areas.

● Water consumption
The hybridization of a cooling tower is the transition from a full wet cooling tower to a hybrid cooling tower. Cooling system hybridizations minimize environmental impact with the addition of a dry section to wet cooling towers. These dry sections are basically conventional air-cooled heat exchangers located in the upper part of the structure above the drift eliminators.
The dry section is equipped with dampers to control the air flow in accordance with the actual environmental conditions. The maximum hybrid cooling tower thermal performance, calculated through the cold-water temperature leaving the tower, is achieved when the cooling tower runs in a wet configuration, with dampers totally closed. On the other hand, the maximum plume abatement capability is achieved when the air flow is delivered to the dry section, with dampers totally opened.
A vacuum system is added to the tower to remove air from the top of tube bundles both during the start-up sequence and during the normal operation to control proper water volumes in the dry section.
The hybrid design combines dry cooling with wet cooling in a common casing. The hot water flow passes the system in series, starting hot in the dry section located outside of the cooling tower casing just above the drift eliminators. Then, the pre-cooled water is fed to the distribution system and discharged on the fill media of the wet section. A skid vacuum system must be provided to create and maintain the siphon effect in the tube bundles (dry section) which allows the circulating water pumps to run at lower pump head.

● Efficient system working: Hybrid cooling tower used with water treatment system removes all the hazardous chemicals from water and makes it decontaminated. This keeps the hybrid cooling tower parts clean and corrosion-free for a longer time, preparing the system to work at more optimum levels.

● Less maintenance required: Due to clean and corrosion-free hybrid cooling tower parts, the frequency of the requirement of maintaining a hybrid cooling tower is reduced, and the maintenance cost is also reduced.

● Life of the system extends: The water treatment system used in the hybrid cooling tower doesn't allow the chemicals to deposit, which keeps the system corrosion-free and extends the life of the whole system.

● Less energy consumption: With water treatment plants in hybrid cooling towers, the water is re-circulated again and again to ensure that the system is clean enough to work at its full capacity and less energy is used to achieve more output.

● Saves water: Unfiltered water has a high chemical deposit content that has to be flushed through the rushing water to prevent corrosion in the system. Water lost in this process has to be constantly refilled to keep the system running which can constitute too many gallons of water each year. Using an effective filtration system can reduce the amount of blowdown required in the system and save a huge amount of water in the process.

The function of hybrid cooling towers can be explained in relation to the way our bodies use sweat to cool down. When our bodies get too hot, sweat evaporates and creates a cooling effect over our skin. This process lowers our internal body temperature and is the idea behind what makes a hybrid cooling tower work. However, there is more water to cool and evaporate in hybrid cooling towers than the small amount of sweat our bodies generate.
Hybrid cooling towers have fans to replace moisture saturated air, gear drives to operate the fans, water circulation devices, and a heat source to heat runoff.

● Wet bulb temperature
There are several factors that determine if a hybrid cooling tower will fit your industry's needs, including water flow rate, inlet and outlet temperature, and wet bulb temperature. The most confusing of these factors can be the wet bulb temperature. This is the temperature used to figure the relative humidity, which usually changes throughout the day.
Relative humidity is found when the temperature of a dry thermometer is compared with the temperature of a wet bulb thermometer. The two thermometers will usually have different readings, but the water readings will be the same if the air is saturated with water. When 100% relative humidity is reached, the air will not accept any more water. The water on the bulb will not evaporate and the temperature will not read the same as the dry bulb.
The lower the reading on the wet bulb, the lower the relative humidity. With less humidity, the air can accept more moisture and the hybrid cooling tower can reject more heat. The size of the hybrid cooling tower you use should be determined by the max wet bulb reading.

● The speed at which a hybrid cooling tower transfers heat
Hybrid cooling towers do not control the rate of heat transfer, but can transfer the heat they are given. It does not matter how large or small a tower is, heat transfer and evaporation rates never vary. However, the size of the hybrid cooling tower, flow rate, and wet bulb temperature determine the inlet and outlet water temperatures.
The difference between the temperature of the inlet and outlet is not determined by the hybrid cooling tower itself. A tower could cool water from 90 to 80 degrees or 100 to 90 degrees, but the 10 degree difference is not affected by the hybrid cooling tower's size. Although you cannot change the heat transfer rate, you can increase performance through boosting the cubic feet per minute or increasing the surface area.

Zhangjiagang Changshou Industrial Equipment Manufacturing Co., Ltd
The company has a registered capital of RMB 80 million and a production base area of ​​35,000 square meters., and a high-tech and well-trained team of more than 260 employees, including 80 engineering and technical personnel (5 senior engineers and 50 professionals with junior and intermediate titles) and more than 100 certified welders. These employees have the extensive experience in the manufacturing and installation of pressure vessels and the on-site manufacturing of large equipment. In addition to the high-quality production supporting equipment, the company has the advanced and perfect inspection and testing equipment, pressure leakage test equipment, physical and chemical equipment, welding laboratory and so on.