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Heat transfer media |
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A comparison between the heat transfer mediaThermal Fluid, Hot Water and Steam all three heat transfer media have advantages and all of them also do have disadvantages. Fortunately the three systems do not have the same disadvantages; therefore you will surely find the most suitable system to fulfill your heat transfer needs. The following list is not complete, such a list does not exist, but it may be a guidance for those who have to consider a new installation.
Thermal Fluid, heat transfer mediaAdvantagesTransfers heat at high temperature and low pressure. No danger of freezing when the plant stops in the wintertime. Corrosion minimized. The only possible heating medium for higher temperatures, for example, asphalts cargos. Low maintenance costs. Simple operation starts and stops. Disadvantages Huge quantities of thermal oil to be pumped due to low heat transfer value. Liquid flow heat control is complicated and expensive. Risk of discoloring when heating vegetable oil. Risk of high temperature corrosion when heating acids in chemical carriers. The high temperature minimizes the heat recovery from the exhaust gas heat recovering. The thermal oil is expensive and it has to be replaced frequently. The staff usually lacks skills to handle a tube leakage in a thermal heat oil furnace.
Hot Water, heat transfer mediaAdvantagesSimpler plants at low temperature, e.g., lower than the water boiling point. Closed system, continuous water treatment not required. Disadvantages Complicated and expensive pressure control when the temperature is higher than the water boiling point. Relatively large quantities of water to be pumped. Liquid flow, heat control is complicated and expensive.
Steam, heat transfer mediaAdvantagesTransfers huge quantities of heat with comparatively small quantities of steam and water. Lesser expensive heat exchangers. Steam flow and heat control are simple. Use of steam atomized burner is possible. Use of steam soot blowing is possible. Steam can also be used for various cleaning purposes. The steam can also be used to produce power. Disadvantages Requires continuous chemical treatment of the water. Skilled operators required. |
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