Flexible design is crucial to anaerobic digestion of waste
- Published: Wednesday, 16 December 2015 08:38
The waste recycling industry will be facing changes in the future streams of food waste coming into the industry. To meet this great challenge, Xergi has developed a flexible design for anaerobic digestion of organic waste.
The waste recycling industry holds a great potential of increasing national production of green energy and fertilisers. Increased independency in food production and energy production is desirable for most countries, in view of the geopolitical situation of today.
But the waste recycling industry is also facing a great number of challenges which must be dealt with.
“Changes in the food industry will cause changes in the streams of food waste coming into the waste recycling industry. It could be changes in packaging systems and logistics, or it could be some types of food waste disappearing and new waste streams emerging. Xergi is working hard to take these future changes into account when designing biogas plants for the waste recycling industry, says country manager Jørgen Fink.
A complex task
The waste recycling industry will not be able to prepare itself for every possible challenge that may arise in the future. But the right industrial design and flexibility of anaerobic digestion plants could increase the ability to handle future changes in food waste streams.
It is a relatively complex task to receive large amounts of food waste from various sources like households, supermarkets, and food industries such as dairies, slaughter houses etc.
This requires choices of the best available technologies for de-packaging specific types of food waste in order to avoid small pieces of plastic or other unwanted elements in the digesting system.
The biological balance
“Based on more than 30 years of experience from construction of anaerobic digestion plants using multiple types of biomass, we have developed an anaerobic digestion system which provides great flexibility for the waste recycling industry,” explains Jørgen Fink.
Xergi has designed the feeding system FLEXFEED® which is a combined mixing, heating, and feeding module. Due to highly precise feeding of the individual biomass, the biological balance in the digester will remain at its most efficient level, even with large variations in the feedstock.
Efficient digesting system
Xergi’s GASMAX® digester system is also designed with the purpose of receiving various types of waste and optimizing the anaerobic digestion processes at the same time.
Complete mixing of the digester is crucial to optimizing gas yields and reducing maintenance costs by avoiding sedimentation and floating layer in the digester.
The digester is therefore designed with a diameter/height ratio of approx. 1:1 and with a central, top-mounted mixing system. Engineering analysis as well as practical experience has shown that this design gives the optimum mixing with the lowest energy consumption.
Operational knowledge and digital monitoring
Xergi’s biogas plants are completed with top quality monitoring and regulating systems developed by Xergi’s engineers.
“But you may have the world’s best anaerobic digestion design and the best monitoring and operating systems, yet successful operation of a biogas plant depends highly on the skills of the operating staff,” says Jørgen Fink.
Therefore Xergi always runs an extremely thorough commissioning process, where training of the operating staff will ensure that they know how to achieve an optimal biogas production.
Economy of scale
Jorgen Fink states that Xergi has made a clear strategic choice of developing an anaerobic digestion design for waste processing on an industrial scale:
“Based on many years of experience, we are convinced that economy of scale will be necessary to meet the future challenges of food waste recycling. One important step in this direction will be highly efficient and flexible large scale biogas plants.”
For more information, contact:
CEO Jørgen Ballermann, tel: +45 99351600, firstname.lastname@example.org