How is circulating water cooled in the chemical industry?

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How is circulating water cooled in the chemical industry? Article source: Xianji Network Date: 2016-07-23 The cooling of circulating water occurs through the contact between water and air, as a result of three processes: heat dissipation by evaporation, heat dissipation through contact, and heat dissipation by radiation. http://www.*anjichina.com/data/editer/20160723/image/4c9297c86eb7431b63e6d4061ce9d6d6.jpg (1) Evaporative cooling. In cooling equipment, water forms larger or smaller droplets or extremely thin films, which increases its surface area of contact with air and prolongs the time of contact. This enhances the evaporation of water, allowing steam to carry away the heat required for vaporization, thereby cooling the water. (2) Contact heat dissipation. Heat transfer through conduction and convection is known as contact heat dissipation. When the water surface comes into contact with air at a lower temperature, the temperature difference causes heat from the hot water to transfer into the air, resulting in a decrease in the water temperature. The greater the temperature difference, the better the heat transfer effect. (3) Radiative heat dissipation. Radiative heat dissipation does not require the presence of a heat transfer medium; rather, it is a phenomenon in which thermal energy is transmitted in the form of electromagnetic waves. Radiative cooling is effective only in large cooling ponds. In other types of cooling devices, radiative heat dissipation can be ignored. The role of these three heat dissipation processes in water cooling varies depending on the physical properties of the air. During the spring, summer, and autumn seasons, when outdoor temperatures are high, surface evaporation plays a major role. In the hottest months of summer, evaporation accounts for over 90% of the total heat dissipation, which means that water loss through evaporation is at its highest, and thus the amount of water that needs to be replenished is also the greatest. In winter, as temperatures drop, the effect of heat loss through contact increases, rising from 10%–20% in summer to 40%–50%; in extremely cold weather, it can even reach around 70%. As a result, the amount of water lost through evaporation decreases during the cold seasons, and accordingly, the amount of water that needs to be replenished also decreases.