This desulphurization is particularly safe and economical when special gas non-return valves made by the German company WITT-Gasetechnik are used. The fittings with DVGW approval prevent the formation of ignitable mixtures.
Biogas results from the fermentation of organic material in a fermenter. The main component of this energy source is combustible methane (methyl hydrogen). Before the biogas is actually utilized energetically, as in combined heat and power plants, air or oxygen is introduced in a controlled manner into the biogas tank for desulphurization. Gas non-return valves only allow the added air through in one direction and prevent the return of biogas into the air supply line leading to the compressor.
The German manufacturer WITT has a gas non-return valve suitable for this in its product range. The “600 ES,” which has been specially developed for corrosive environments, is a fitting with only 65 mm overall length and 56 mm diameter. According to the manufacturer, it can do more than equivalent types. A pertinent example is its response at very low opening pressures. The low pressure losses between the compressor and tank enable the use of smaller compressors and small pipe cross sections, thereby boosting economic viability. High-quality stainless steel and an integrated dirt filter enable a long service life.
As a special feature, WITT checks every fitting before delivery in accordance with EN 730-2. Furthermore, the gas non-return valve is inspected externally and certified by the DVGW (Deutscher Verein des Gas- und Wasserfaches or German Technical and Scientific Association for Gas and Water).
WITT gas non-return valves can be installed easily in existing air supply lines independently of location. A large selection of connection options enables installation in practically any system. Variants for high pressure and high temperature are available.