Weltc Builds Biomethane Plant for French Potato Chip Manufacturer
Biogas plant builder Weltec Biopower completed a biomethane plant for Altho, a French manufacturer of potato chips for private label in St. Gerand, Brittany. The plant was planned and set up by the German manufacturer in collaboration with its French partner, Weltec France
Some 200 standard m3/h of biomethane are generated from production waste and sludge from the company’s own wastewater treatment plant. This corresponds to the gas consumption of a town with a population of 5,000.
For more than a year, France has promoted the establishment of biomethane plants. Now, an action package implemented by the government makes sure that the projects can be rolled out speedily and with minimum bureaucracy.
The biomethane production is in line with the CSR (corporate social responsibility) policy of Altho, which holds more than a third of the market share with its chips brand “Bret’s”.
“Via the Altho subsidiary Sober, which operates the biogas plant, we actively participate in recycling, producing a green energy source from waste. Additionally, we contribute to the reduction of greenhouse emissions and the energy dependence of the region”, says Christophe Chrétien, managing director of the biogas plant of Sober.
The chips production yields 22,000t of leftovers and sludge a year. Potato and starch leftovers as well as other production waste account for about half of the substrate; the rest is made up of the sludge from the washing process.
First, the solid and liquid substrates are mashed and shredded in the sturdy MULTIMix input system. After this pre-processing, the mixture is fed into the stainless-steel digester, which has a capacity of 4,436 m³. A post-digester with the same capacity is the last step in the material cycle. Subsequently, the digestate is sold to local farmers, who use it as high-quality fertilizer.
The process that transforms the biogas into biomethane also stands out with its sustainability: to condition the biogas, Weltec Biopower has integrated the membrane technology in a compact container solution.
With this equipment, Altho is able to focus on its core business and make efficient use of accumulating leftovers. This fills an urgent need, as many French biogas operators struggle with technical problems. A survey conducted by the ATEE (Association Technique Energie Environment) has revealed some sobering results: 94% of the plant operators had technical problems, and 65% did not see their efficiency expectations fulfilled. This was usually because the technology did not meet the requirements. In view of these challenges, the cooperation between Weltec Biopower and Weltec France is just what is needed.