Steam line blowing is an operational cleaning method used to clean steam piping and reheaters prior to turbine powering for steam power plants. This paper focusses on the application and challenges associated with the steam blowing of large solar thermal collection power plants.
The boiler configuration, located atop an over 400 foot tall tower, in a large solar thermal collection plant poses some challenges not associated with other steam supply methods. As a result of the flow path configurations and steam mass required for blowing the cold reheat, reheater, and hot reheat portions of the plant, attemperation is required to control temperatures in the reheater. The use of multiple flow paths and stages through the reheater also requires some additional consideration. Where in a fossil powered plant the losses through the reheater are based on the inlet vs. outlet conditions, additional vendor data is required to model the internal sections of the reheater in greater detail.
Methodologies developed for fossil powered plants can be applied to large solar thermal collectors with special consideration for the unique configurations and constantly changing solar conditions associated with the plants. The smaller margins associated with these plants requires more rigorous modeling of the system components.