Question: Syncrude Canada Ltd. has contracted the services of a consulting firm to assess the performance of a small steam-turbine plant. This existing plant has a single-stage steam turbine and one stage of closed feedwater heating, which comes complete with drain cooling. It has been specified that the full-load steam mass flow rate is 255000 lb/h.
The turbine inlet conditions are 1000 psia and 900?F. Steam is extracted from the turbine at 200 psia for feed water heating. Losses in the plant system result in a turbine internal efficiency of 86%, a pump efficiency of 70%, and a total boiler pressure drop of 60 psia. An auxiliary power requirement of 8% will be derived from the steam turbine to maintain plant operations. Using practical knowledge of steam turbine plants (where applicable), conduct an appropriate analysis to prepare a heat-and-mass balance diagram for full-load operation of the plant. Was a desuperheating zone of tubes installed in the feed water heat exchanger?