Dansih BME has supplied a furnace for straw based CHP in Germany
Danish BME has supplied a grate for a straw based plant in Germany. From the left the straw bales are conveyed through the fire barriers to the scarifiers. From here the
scarified straw is fed on to the water cooled vibration grate where it is burned. The boiler is of the drum type with natural circulation. BWE has developed a straw firing system adaptable to different types of squared bales such as Heston and CLAAS.

Germany’s first straw-fired heating plant in commission soon

Germany’s first straw-fired heating plant will soon be commissioned in Emlichheim. Burning approximately 60,000 metric tons of straw per year, it will supply heat to Emsland-Stärke GmbH, public facilities and private households as well.

In cooperation with the German Company BE Bioenergie BWE has installed the first straw fired steam generator in Germany which will supply process steam and electricity to a nearby process installation as well as district heating to Emlichheim city and electricity to the grid

The boiler of the Emsland Bioenergy Power Plant has been in operation since the summer. However, the plant in Emlichheim is still in trial operation, as the approximately 20 employees of the operator BEKW Bioenergiekraftwerk Emsland continue to fine-tune the complex installation. Soon the plant will be ready and Germany’s first straw-fired heating plant will be officially started up.

“We have around 6,000 measuring points in the power plant”, says Rainer Knieper, the chief engineer, adding that the installation is being fine-tuned based on the values obtained. “It’s like tuning an engine”, he explains. One of the results is that the emission threshold values for dust, at 0.1 to 0.6 milligrams per standard cubic meter, lie far below the prescribed maximum value of 20.

The main customers will be Emsland-Stärke GmbH, the district of Emlichheim and the Evangelische Krankenhausverein hospital association. The “green” heat will be used to heat the town hall, the primary school and the school complex, among other places. Approximately 150 households are also already linked up to the power plant’s district heating network, which now has a length of around 30 kilometers.

The idea of building a power plant fired exclusively with straw was conceived almost ten years ago, and the commissioning was actually planned for the end of 2012. However, the implementation of the project was repeatedly held up.

Although BEKW obtained the construction and operating permit for the straw-fired heating plant at the end of 2008, the construction was only completed in February 2011. Only when straw was “literally” included as a raw material on the list of the Renewable Energies Act in 2009 could the project gain momentum.

The initiators were then faced with the task of securing the financing for Germany’s first straw-fired heating plant, estimated at €56 million. In September 2010, the operator was promised five million euros of funding by the Federal Ministry for the Environment. A short time later, the state of Lower Saxony provided a state guarantee for the project.

The fact that boiler output of approximately 50,000 kilowatt hours per year will be achieved based on straw alone as the raw material is a first in Germany, says Knieper. “There are also power plants with such capacity in Denmark, the UK, Spain and other countries,” says the engineer. A special characteristic of the German plant is that large bales with different heights can be processed. In the other plants a fixed standard size must be used.

To secure the supply of straw, most of which will come from the Münster and Emsland region, contracts were concluded with suppliers several years ago. “The power plant needs around 60,000 metric tons of straw per year”, says Knieper. “That is a football field full of square bales stacked 60 meters high.

” That means that approximately twelve metric tons of straw will be burned per hour when the plant is running at full capacity. However, most of the time the plant will be run at partial capacity.

However, the straw-burning cycle in Emlichheim does not end with the generation of heat. The “by-product ash” is included in the Fertilizer Regulation as a permissible substance, and the straw-fired heating plant also generates electricity. BEKW is therefore currently working on a concept to market the electricity directly, says engineer Rainer Knieper. Source