Lignite Drying - WTATM
For many years, RWE has been working on research development to find ways of increasing efficiency at its lignite-fired power stations. We have now developed a revolutionary fluidized bed drying technology called WTA, with built-in waste heat recovery. The technology enables wet lignite to be dried quickly in an energy-efficient way.
RWE is developing processes that further increase the efficiencies of lignite-fired power plants. One method is fluidized-bed lignite drying with internal waste heat utilisation, WTA for short (Wirbelschicht-Trocknung mit interner Abwärmenutzung). This lignite drying technology was developed by RWE know-how and permits run-of-mine lignite to be dried efficiently prior to use. In this way, the efficiencies of future lignite-based power plants are increased by a further 10% along with a corresponding reduction of carbon emissions.
In 2009, RWE commissioned the commercial-sized prototype WTA lignite drying plant at Niederaußem. It is installed upstream of the 1,000MW BoA unit and is intended to help replace 20 to 30 percent of the run-of-mine lignite otherwise required. By 2010, the plant will have proven whether or not the continuous use of the WTA drying process is suitable for lignite-based power generation in technical and economic terms. RWE is investing some 50 million euros in the project. If this technology proves its worth, it will be used in future new-build projects.
RWE Power International markets the WTATM technology world-wide together with RWE-approved suppliers of WTATM plants.
Our services cover all the stages of developing a WTATM plant:
- opportunity studies
- laboratory scale tests
- industrial scale drying tests
- basic design of WTATM drying plants
In addition, RWE Power International supports the RWE-approved suppliers throughout the detailed engineering, construction and commissioning of WTATM plants and in the training of operating staff.

