How to determine the effectiveness of a cooling tower in cooling?

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In the petroleum refining industry, cooling towers play a very important role. The importance of cooling towers: Cooling towers play a crucial role in heat dissipation in many fields. It can effectively lower water temperature, ensuring the proper operation of various devices and systems. If the cooling tower does not function properly, it will lead to excessively high water temperatures, which in turn affects the performance and lifespan of the equipment, and may even cause failures. Therefore, understanding the working principle and process of cooling towers is essential to ensuring their efficient operation. Basic working principle of cooling towers: Dry (low enthalpy) air is drawn into the cooling tower through the air intake by a fan. At this point, high-temperature water molecules with a high saturated vapor partial pressure move toward the air at lower pressure, while the humid and hot water (with high enthalpy) is sprayed into the tower from the water distribution system. When water droplets come into contact with air, two effects occur. On the one hand, due to direct heat transfer between air and water, heat is transferred from water to air. On the other hand, due to the pressure difference between the water vapor surface and the air, evaporation occurs under the influence of this pressure; the latent heat of vaporization is carried away, thereby removing heat from the water – this is known as evaporative heat transfer. Through these two methods, the cooling tower achieves the purpose of cooling down. The working process of a cooling tower is illustrated using the example of a circular counterflow cooling tower. Hot water is pumped from the main machine room under certain pressure through pipes, cross nozzles, curved nozzles, and central nozzles, and is then delivered to the water distribution system of the cooling tower. Then, through the small holes in the water distribution pipe, the water is evenly spread over the filler. Dry air with a low humidity value enters the tower through the air inlet network at the bottom, driven by a fan. When hot water flows over the surface of the filler, a water film is formed, which exchanges heat with the air. The hot air with high humidity and high humidity value is drawn out from the top, while the cooled water drops into the bottom basin and then flows back to the main unit through the outlet pipe. Under normal circumstances, the air entering the tower is dry air with a low wet-bulb temperature. In this case, there is a clear difference in the concentration of water molecules as well as a difference in kinetic pressure between water and air. When the fan is operating, under the effect of the static pressure inside the tower, water molecules continuously evaporate into the air to become water vapor molecules. As water molecules evaporate, the average kinetic energy of the remaining water molecules decreases, thereby lowering the temperature of the circulating water. Over time, industrial cooling water towers experience issues such as filler blockage and collapse, inefficient fans, and uneven water distribution during long-term operation, which leads to a decline in their cooling capacity. For example, in chemical manufacturing plants, if the heat generated by the normal operation of various units and equipment cannot be discharged promptly through cooling towers, it can in severe cases cause these units and equipment to fail, resulting in a halt in production. It is a very important and necessary task for enterprises in the petroleum refining industry to conduct thermal performance tests and comprehensive evaluations of cooling towers; this also represents an opportunity to save water. This test is not only related to whether the cooling capacity of the cooling tower meets the required standards, but also to whether its long-term operation can satisfy the needs of normal production. Therefore, it is necessary to conduct regular thermal performance tests on parameters such as the cooling efficiency, cooling capacity, air-to-water ratio, and water drift rate of the cooling tower. This provides a scientific basis for evaluating its heat and mass transfer performance, helps to improve the utilization rate of circulating water, and thus achieves the goal of water conservation. Smart Golden Horse has been serving petrochemical companies for a long time, and possesses extensive experience and advantages in thermal performance testing services. It ensures that cooling towers operate at their optimal performance, effectively improving the utilization rate of circulating water in these companies and helping them save water. The thermal performance of the cooling tower is evaluated by accurately measuring its operating conditions and environmental parameters. By performing thermal calculations for various operating conditions, as well as calculations related to the cooling capacity and the volumetric dispersion system, the actual cooling capacity of the cooling tower can be determined. This allows for a comprehensive assessment of the tower’s cooling efficiency, ensuring that it operates at its optimal performance level. In the cooling tower tests, the main items we test are divided into 7 categories, namely: environmental and meteorological parameters, including dry and wet bulb air temperatures, atmospheric pressure, wind speed, and wind direction ； Dry and wet bulb temperatures of air entering the tower ； Water flow rate into the tower ； Inlet and outlet tower water temperature ； Air flow into the tower ； Dynamic pressure and total pressure at the throat of the cooling tower fan ； The fan shaft power and the installation angle of the fan blades in mechanical ventilation cooling towers. Each test item has a fixed number of tests and interval times as required by national standards, with the actual testing being carried out in accordance with the specified on-site testing requirements. For industrial enterprises, conducting thermal performance tests on cooling towers can effectively improve the utilization rate of circulating water, help save water, and ensure operational safety. Smart Golden Horse always provides petrochemical enterprises with safe, efficient, convenient, and user-friendly one-stop solutions and robust services, driving industry development and ensuring production safety!