WELTEC BIOPOWER commissions fourth biogas project in Japan
The facility, equipped with a 450 kW co-generation power plant, is the fourth project rolled out by the German manufacturer in Japan. The plant uses organic leftovers from the vicinity – 40 kilometres north of Tokyo. As the plant’s raw material mix varies, Weltec ensures a steady biogas output with its unique biological service.
Renewable energy in Japan today accounts for a fifth of power generated in the country. Weltec highlighted that leftovers (waste) are the preferred substrates in Japan.
The biogas plant in Saitama digests approximately 12,000 tonnes of organic waste per day. The substrate mix consists of organic waste and cow manure from a nearby farm that belongs to the operator. The largely liquid organics are pumped into the digester while solid feedstocks are transported by a dosing feeder with a capacity of 27 m3.
To ensure efficient digester, Weltec set up a stainless-steel digester with a 2,823 m3 capacity. The upstream substrate storage tank, made of stainless steel, has a capacity of 336 m3. The 525 m3 digestate storage tank is also made of high-quality stainless steel.
The digestate is separated and the solid phase is dried with special technology to further reduce the volume. Most of this residue is used as compost, and some as fertiliser.
“The Japanese appreciate the custom plant design and the benefits of our modular approach, especially because the plant structure with stainless steel modules facilitates the consideration of the special risks in areas that experience a lot of seismic activity,” said Vladimir Bogatov, who is responsible for sales at Weltec.
In addition to constructing this facility, the Japanese operator entrusted Weltec with the biological supervision of its other biogas plant, set up by a different provider in 2017. As this plant’s yield was above average, Weltec’s biology experts arranged for the substrate mix of the old plant to be analysed by a Japanese lab. Based on the results, the raw material mix and retention time have been optimised.
Due to the constantly changing composition of the waste, Weltec will continue to supervise the two plants biologically to maximise the gas yield.