Innovative, yet based exclusively on proven technologies, BEBRA geo takes digester and storage technology for biogas plants one step further towards lower investment, lower maintenance effort and lower ownership costs.
No compromises are made with respect to safety and quality, yet BEBRA geo can be up to 50% cheaper than conventional biogas digesters or storage tanks.
Conventional digesters or storage tanks are concrete or steel structures with an inside coating or liner against the aggressive biogas, and abrasive substrates. BEBRA geo does not require concrete or steel walls, as the two-layer impermeable geomembrane with en expected lifetime of over 100 years is placed directly into a man-made trough, where the earth excavated from the centre is used for the embankments. The individual sheets are seamed by “dual track hot wedge” thermal fusion; every single seam is checked for tightness after completion.
The geomembrane is comparable to those used in modern landfills. It can be stretched to 600% without tearing, and is resistant to UV radiation and aggressive substances such as slurry or silo effluents. The absence of concrete or steel digester walls eliminates any risk of corrosion and leakage, or any need for re-coating of the inside walls, and guarantees the same high quality everywhere, independently of varying concrete or coating qualities.
As BEBRA geo digesters are partially, or fully, built into the ground, only the embankment and the optional gas storage dome rise above the ground level. The embankment is typically 2.5 m high, the height of the gas storage dome typically equals one fourth of the width of the digester.