Weltec Biopower breaks ground on Australian biogas project

By Weltec Biopower | November 06, 2015

On. Oct. 19, the ground was broken for one of Australia's most innovative biogas projects. In the next 14 months, German biogas plant manufacturer Weltec Biopower and its project partner, Aquatec Maxcon, will establish a biogas plant in a Melbourne suburb. The 1-MW plant for the anaerobic digestion of organic waste will be one of the first of its kind in Australia.

The customer, Yarra Valley Water, is one of Australia's largest enterprises providing water supply and sewerage services. Through the biogas production, Yarra Valley Water will become energy self-sufficient at the plant location in Aurora. “The purpose built Waste to Energy facility will provide an environmentally sustainable solution for commercial organic wastes, generating enough renewable energy to run the existing sewage and recycled water treatment plants, as well as other Yarra Valley Water facilities,” said Pat McCafferty, managing director of Yarra Valley Water. The two 530-kilowatt MAN engines are even producing as much electricity that an unused surplus can be fed into the public grid.

The two stainless-steel digesters in Aurora, each of which has a capacity of 3,573m³, will be fed with 100 tons of organic waste a day. More than half of this amount will come from cafeterias and restaurants. The rest will comprise fats and oils, brewery and dairy leftovers, fruit and vegetable waste and sludge that will be pumped from the adjacent wastewater treatment plant. After the digestion process, the substrate will first be sanitized and then buffered in a stainless-steel tank of 4,531m³.

A custom-tailored input process will be set up to ensure uninterrupted supply of the biogas plant. At the delivery area, the feedstocks will first be loaded into two 35m³ solids hopper feeder. Part of the substrates, such as melon peels, will first be shredded and then further chopped up with other raw materials and mixed with recirculation fluid in the MULTIMix system. After this preliminary treatment, the mixture will be pumped into the largest of the five stainless steel prestorage tanks with a total volume of almost 700m³.

Except for the loading of the input systems, the process is fully automated. The size of the prestorage tanks was designed in such a way that no loading and thus no manpower will be required at the weekend and at night. Weltec's custom-developed LoMOS PLC will make sure that the substrate is automatically pumped from the pre-storage tanks to the digesters, thereby ensuring continuous digestion at the weekend.

"Our knowledge and experience in rolling out the technology of such a project was a key factor in our selection as the first German biogas plant manufacturer to build a plant in Australia. We are proud of being represented on five continents with about 300 biogas plants," summarized Jens Albartus, director of Weltec Biopower.