Work is underway in England and Scotland on a series of landmark trials examining the potential for using anaerobic digestion as an alternative to commercial fertilisers in landscaping and regeneration projects.
The studies, organised by waste and resources action programme (WRAP), could have significant bearing for the UK’s burgeoning anaerobic digestion (AD) industry by opening up potential new markets for digestate; the nutrient-rich bio-fertiliser produced as part of the AD treatment process for organic waste.
The results could offer a cost effective alternative to expensive commercial fertilisers for the UK’s landscape and regeneration sectors; benefiting small independent firms and large environmental regeneration projects.
“We have seen significant improvement in how vegetation establishes itself in brownfield restoration and sport turfs through the use of compost,” said WRAP programme manager Paul Mathers. “I am confident that anaerobic digestate offers similar environmental and economic benefits.
“If successful, the results will have far reaching implications for a wide range of regeneration programmes and sports turf applications. The use of anaerobic digestate could open new markets on a national scale.”
In Yorkshire, Walker Resource Management (WRM) is working in partnership with the Sports Turf Research Institute (STRI) to examine the effectiveness of anaerobic digestate when used as a sports turf fertiliser.
Two field trials, one held at the STRI grounds and the second at Marsden Park golf course in Lancashire, will compare the performance of anaerobic digestate when injected into golf greens and fairways against surface application.
The trial plots will be compared with ones treated with conventional industry fertiliser, and with untreated control sites. Grass cover will be measured and photographed monthly, and assessed by chlorophyll meter. The trials will run until early spring.
Further WRAP trials are also underway in Scotland, this time examining the use of anaerobic digestate in the establishment of newly planted trees and energy crops.
Anaerobic digestion involves the breaking down of biodegradable material using micro-organisms in the absence of oxygen.
It is currently used to treat wastewater at sewage treatment works in the UK, but can also be used to treat other organics wastes including household food waste, farmyard manures and energy crops.
The process also provides a source of renewable energy in the form of biogas (a mixture of methane and carbon dioxide)