Cleaning of turbine condensers

operational problems of turbine condensers

During the operation of turbine condensers, water deposits and corrosion products are released on the inner surfaces of condenser tubes. The main components of the deposits are mostly:

• carbonates
• alkaline carbonates
• silicates and sulfates of metals such as calcium, magnesium, iron, copper and zinc

This problem is particularly exacerbated in open-circuit cooling systems fed by river water. Water quality changes depending on the season and weather conditions. Due to the nature of the source, significant amounts of river silt, sand, fine wood and organic particles are carried into the condensers. These contaminants, deposited on the screen bottoms of the condensers, can cause restriction of water flow in the tubes. This worsens the heat exchange, and the increase in temperature promotes the loss of carbonate deposits and the decomposition of organic compounds into nitrates, nitrites, ammonia, sulfides, etc.

The thickness of the sediments can vary from one to several millimeters Analyses of the structures of individual sediment layers indicate that the process of their formation is very different and non-uniform, which is due to the periodic occurrence of significant amounts of suspended solids.

In order to ensure proper and optimal operation of the equipment, it is necessary to maintain a high level of cleanliness of the internal surface of condenser tubes, both because of the need to ensure good heat transfer and because of the reduction of the intensity of corrosion processes (sub-sedimentary, selective and other corrosion). It is therefore necessary to periodically operate and overhaul the tubes using methods appropriate to the type of sediment, tube material and exchanger design.

safety of the active foam technology used

The deposits which are removed during chemical cleaning of condenser tubes are primarily those which are released from the coolant on the inner surface of the tubes, as well as oxide protective layers which form during the operation of brass tubes in contact with the cooling water.

Inhibition of the cleaning solution used in active foam technology, minimizes the negative effects of the chemical components of the cleaning bath on the specific surfaces of brass tubes.

a typical cleaning process using active foam consists of the following steps:

The total time of the process of chemical cleaning with active foam for condensers, is from several to several hours, depending on the size of the system, the type of deposits and the type of construction materials.