Cleaning of steam and gas turbines

After the cleaning operation is completed, the interior of the turbine is decontaminated, i.e. washed with chemically neutral foam generated from the condensate and then with saturated steam, until all residues of the chemicals used are completely rinsed out.

All operations related to the introduction of foam into the turbine, saturated steam rinsing and collection of wastewater from the process, require the development of a detailed plan for preparatory work in terms of occupational and environmental safety, foam introduction technique, protection against foam leaks into undesirable areas and the conduct of collection of wastewater from the process.

preventive cleaning as a solution to sludge re-growth

Although the technique of chemical cleaning of turbine interiors using chemically active foam has found recognition as a good solution implemented during planned overhauls, nowadays its advantages are increasingly being used to restore nominal turbine performance during the life cycle (i.e., between overhauls).

benefits of the proposed technology:

• making the planning of operating periods more flexible
• extending inter-overhaul periods
• maintenance of a turbine’s relatively constant operating efficiency, without waiting for a major overhaul
• preventive removal of deposits from flow systems

For turbines where the problem of sludge buildup recurs, the use of the chemical foam method can be considered as a tool for the preventive restoration of the turbine’s nominal performance during periods between overhauls.

frequency of preventive foam cleaning

The frequency of preventive foam cleaning must find its economic justification, and will certainly be an individual (for a given turbine) resultant of many factors, such as:

• the rate of performance deterioration
• lost production benefits due to deterioration of efficiency and performance
• the possibility of setting the turbine aside to perform cleaning
• the technical risks of operating a contaminated turbine, and others