Abstract
Steam pressure reduction has the potential to reduce fuel consumption for a minimum capital investment. When the pressure at the boiler is reduced, fuel and steam are saved as a result of changes in the high-pressure side of the steam system from the boiler through the condensate return system.
In the boiler plant, losses from combustion, boiler blowdown, radiation, and steam venting from condensate receivers would be reduced by reducing steam pressure. Similarly, in the steam distribution system, losses from radiation, flash steam vented from condensate receivers, and component and steam trap leakage would also be reduced. There are potential problems associated with steam pressure reduction, however. These may include increased boiler carryover, boiler water circulation problems in watertube boilers, increased steam velocity in piping, loss of power in steam turbines, and issues with
pressure reducing valves.
This paper is based a Steam Technical Brief sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and Enbridge Gas Distribution, Inc. (5). An example illustrates the use of DOE BestPractices Steam System Assessment Tool to model changes in steam, fuel, electricity generation, and makeup water and to estimate resulting economic benefits.