Steam is widely used as an energy source in various industries, such as power generation, petroleum, chemical industry, printing and dyeing, papermaking, light textile, brewing, rubber, pottery and other industrial fields. Steam is often used as a heat source, but in reality, only the latent heat of steam is used, and the sensible heat of steam - the heat contained in condensed water - is almost completely discarded. This is because in order to improve the production efficiency, i.e. heating efficiency, of steam using equipment, it is necessary to quickly discharge condensate with low heat transfer efficiency from the steam. However, the condensed water after steam does work still has a lot of heat, and making good use of this heat can achieve significant energy-saving benefits.
After releasing the latent heat of vaporization in various steam consuming equipment, steam becomes saturated condensate at almost the same temperature and pressure. Due to the use pressure of steam being greater than atmospheric pressure, the heat contained in condensed water can reach 20% -30% of the total heat of steam. The higher the pressure and temperature, the more heat condensed water has, and the greater its proportion to the total heat of steam. This can be seen from the steam table. If the heat from the condensate can be recovered 100% and effectively utilized, the fuel required for the boiler can be saved by 20% -30%.
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The recovery of condensate water refers to the recovery and reuse of the heat and water content of steam condensate water, and its benefits can be summarized as follows:
1. Save boiler fuel.
2. Save industrial water. Condensed water can generally be directly used as boiler feed water, which can significantly reduce industrial water consumption. The treated water can still be effectively utilized.
3. Save on boiler feedwater treatment costs. Due to the fact that condensate water can be directly used for boiler feedwater, the cost of softening treatment for this portion of water can be saved.
4. The reduction of fuel combustion can reduce air pollution, and the recovery of heat can reduce the fuel consumption of boilers, thereby reducing the emissions of smoke and sulfur dioxide. At the same time, it eliminates the heat generated by the discharge of condensate water and improves the working environment.
5. Improve the actual thermal efficiency of the boiler. Due to the utilization of condensate water, the temperature of boiler feedwater rises, fuel is saved, and the actual thermal efficiency of the boiler is improved, fully tapping into the potential of the boiler. It can be seen that the energy-saving potential of condensate water recovery is enormous.
