In sugar plants, during shutdown, turbines and other electromechanical equipment corrode because of moisture present in the surrounding air, hence, leading to high replacement costs.
During shutdown, Relative Humidity should be maintained at 15%-30% RH at 24ºC (75ºF) and during operation, at less than 35% RH at ambient temperature to minimise the loss due to corrosion.
There are two types of turbines: Condensing type and other Extraction type. Preservation of turbine is done for both types with the help of desiccant based dehumidifier.
Dehumidifier is installed near the turbine and from the process inlet of the dehumidifier, ambient air is taken and from the process outlet of the dehumidifier,dry dehumid moisture free air is supplied into the turbine. This connection is done on relief valve/drain pipe /cross overhead pipe in the turbine or other available outlet. Dryair ensures that the turbine is under optimum preservation by controlling moisture and humidity during idle stage or during shutdown of sugar plant.
TDS provides desiccant based dehumidifiers to maintain recommended Relative Humidity (RH).
The process outlet of dehumidifier is connected at a convenient location like at the release valve or at any suitable opening. In case of condensing type turbine the outlet is given through the condenser. Thus, the turbine is preserved under low moisture conditions free from dust. The best method to check humidity is by measuring the outlet air humidity of turbine that will signify the optimum conditions maintained within the turbine.