| 摘要 |
A system for improving the efficiency of a modern powerplant (1) for generating electricity that has a water-cooled shell and tube steam condenser (3, 4) with an air removal system. An air removal system typically includes an air offtake pipe (10) and a two-stage liquid ring vacuum pump (29). This invention adds a pressure control system to lower the operating pressure at the inlet of the vacuum pump of the air removal system so that an optimum minimum pressure is attained to reduce air inventory inside the condenser. This enhances heat transfer and improves power plant efficiency. The pressure control system contains a pressure control device (30) (e.g. miniature condenser), a chiller, (32) and a pump with variable speed (31). These components are connected in a loop that circulates cold water. Part of the steam in the steam-air mixture from the condenser, a chiller (32) and a pump with variable speed (31). These components are connected in a loop that circulates cold water. Part of the steam in the steam-air mixture from the condenser (3, 4) is condensed while passing through the pressure control device (30). The pressure control system adjusts the condensation rate in the pressure control device to yield the optimum minimum pressure.
|
