Dehumidifiers & dehumidification for power plants & steam turbines

The demand for generated power is constantly variable, resulting in plants being brought online at peak demand, typically in winter, and long periods of downtime during the summer months. Whilst there are a number of different technologies used, gas turbine, micro gas turbines, steam turbines are still the largest source of generated power globally and has been for the last 140 years.

There are different types of turbine, condensing, non-condensing, reheat and extracting, but the underlying basic principle of operation is common. Steam turbines operate on the Rankine cycle. In this thermodynamic cycle, water is pumped to high pressure and then heated to generate high pressure steam. The high pressure steam is then expanded through a steam turbine where steam energy is converted to mechanical power that drives an electrical generator.

Steam at pressure is often referred to as dry steam. Extra energy in the form of sensible heat is added at the superheater. This keeps the steam from condensing in the piping or in the turbine nozzles. This ensures that only steam, as a gas, reaches the turbines. This prevents condensed water droplets impinging on the turbine blades. However when a turbine is shutdown and pressure reduces there is a high risk of condensate forming. Liquid water can lead to corrosion on the blades of the turbine, as well as the casing if not removed.

When power plants are taken offline for maintenance or because of excess generator capacity, removal of condensate is an important aspect to be considered. Dehumidifiers can be installed to blow dry air through both the steam side and generator windings. This costs less and is safer than purging with nitrogen, and is far more effective than either wet layup with corrosion inhibitors or preservation in grease. “Dry air layup” is very simple, and the plant can go back on-line in a matter of hours rather than weeks.

  • Desiccant (adsorption) dehumidifier systems offer the best solution. They can be comparatively small and portable. They offer a wider range of operational temperatures typically -30 to +40 °C together with inlet ambient humidity from 0-100%RH. Operationally they can provide humidity levels below 10%RH.

    Dry air discharge temperatures can be in the order of 35 to 45°C, which assists in moisture removal. The great flexibility of desiccant dehumidifiers make them ideal for unheated environments.

Benefits of Condair dehumidification in power plants include:

  • Prevents corrosion on turbine blades during downtime
  • More efficient than wet layup or using corrosion inhibitors
  • Comprehensive range of dehumidification technologies
  • Free expert advice and dehumidifier system design support
  • Local engineering support for reliable operation in critical environments

Bunkermuseum Hanstholm

Erik Ansø

Museumsforvalter

“The noise level is now so low that you can talk normally in the ventilation room even though both the ventilation and a dehumidifier are running, which was one of the criteria. You certainly couldn't do that before, and it's worked out well in a concrete bunker.”

Prime Ocean

Jan Bork Nordmann

Produktion

“The dehumidification solution from Condair is one of the best investments we have made down here.

Prime Ocean is one of Europe’s largest importers of fresh cod from FAO27 and also imports large volumes of salmon. Both fresh fish products and high-quality frozen products are produced. The dehumidification solution has helped eliminate condensation problems, the daily downtime of the machines has been virtually eliminated and the maintenance work on both machines and buildings has been significantly minimized.”

Vyra Suites Hotel in Qatar

Kiran Nair

Sales Engineer at Mentor Trading

“The ceiling mounted dehumidifiers are compact in size and were fixed above the pool and spa areas. We were very satisfied with Condair’s service and their prompt response to the project.

The quality of the Condair DP-C dehumidifiers is of a high standard and they were easy to install and simple for the customer to operate. We look forward to a working with the Condair team in the future.”

T Clarke

Doug Lumb

Project Engineer

“The Condair DC 50W dehumidifier was actually chosen by our designers, as it fitted the bill perfectly for the environment. The unit size was based on the quantities of kit hung in the room to dry when the firefighters return to the Centre at the end of their training exercises.

It’s a reliable product and currently operating at the station just as expected, plus installation was really simple and didn’t take long at all, so all very good.

I would definitely specify Condair dehumidifiers for future projects.”

The Savanna

Lisa Gardshol

Founder and CEO

“We have been very happy with the performance of the Condair dehumidifiers JTR installed to comply with our drying approach. It has not only allowed us to increase production efficiency but also produce our award-winning biltong.

We have full control over the entire process and can make decisions based on the data that we recieve. This is something which we couldn’t do as well before.”

John Todd Refrigeration (JTR)

Matt Gough

Refrigeration Engineer

“The rooms need very tight environmental control but the previous strategy introduced outside air to help lower temperatures when needed. JTR redesigned the drying rooms and installed Condair DC-N dehumidifiers.

The dehumidifiers, located in the rooms, both dry and heat the air to the required condition, resulting in a fully sealed area and a consistently controlled drying process.”

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