| 摘要 |
PURPOSE:To enable to decrease the energy loss during the pressure reduction by a structure wherein a bypass piping is provided with respect to a main steam piping led to the demand side and a steam turbine is arranged in the bypass piping so as to reduce the steam pressure just before the demand down to the pressure required at the demand side by passing a part of steam through the steam turbine. CONSTITUTION:A pressure indicating controller 21 controls valves 2 and 3 so as to obtain steam pressure required at a demand 22 side. However, because the pressure reduction by a pressure reducing valve 2 causes energy loss, the degrees of priority of the valves 2 and 3 are determined in their controlling so as to pass steam as large as possible through a bypass piping 18 in order to reduce the pressure of the steam at a steam turbine 4. In this case, the valve 2 may be fully open, if the steam pressure used at the demand 22 side permits. On the other hand, a flow indicating controller 19 measures the steam flow rate in a main steam pipe 17 and leads the steam exceeding the maximum steam flow rate passing through the pressure reducing valve 2 into an accumulator 5 so as to back-up in response to the increase of the required steam amount. Thus, the energy loss during the pressure reduction can be decreased and yet can be recovered as effective energy. |
