Such emissions result in a manure that is a weaker fertiliser and poorer renewable energy feedstock. This costs farmers money to purchase mineral fertiliser to supplement the weakened manure, which in turn causes additional environmental pollution, while anaerobic digestion (AD) plants must supplement manure with energy crops e.g., maize, grown at the expense of food for consumption, to generate sufficient renewable energy.
With approximately 1.4 billion tonnes of manure produced in Europe each year and forecasted growth in livestock numbers to feed a growing global population, this is an urgent and pressing problem.
GlasPort Bio Ltd (www.glasportbio.com) were recently announced as overall winners of the 2021 Rushlight Awards for GasAbate N+, their novel solution to this problem. The Irish headquartered company have developed an innovative slurry additive which has proved highly effective in reducing all gaseous emissions from stored manure.
GasAbate N+ works by acting on specific microorganisms present in the slurry, in doing so preventing the production and release of methane, ammonia and hydrogen sulphide by these bugs. This acts to lock in carbon and nitrogen in the slurry, thereby increasing its value and greatly reducing the environmental impact. GasAbate N+ is composed of GRAS (generally recognised as safe) ingredients and can be applied to a range of animal wastes e.g., dairy, beef, pig etc., with no harmful residues remaining in the slurry following use.
Results from studies with GasAbate N+ have been very impressive. In a recent trial over an 11-week storage period, GasAbate N+ reduced emissions (methane, ammonia, hydrogen sulphide) from pig slurry by over 90%, while impacting on odours. It is well known that the energy potential of slurry is reduced during storage, with up to 50% of its biogas potential lost during 2 weeks of storage.
Dairy slurry treated with GasAbate N+ over a 96-hour storage period generated 38% more biogas following AD than equivalent untreated slurry. Fertiliser value of treated slurry was also increased. In small-scale pot trials using perennial ryegrass, crops fertilised with GasAbate N+ treated slurry gave a 13% increase in dry matter content.
Dr Ruairi Friel, CEO of GlasPort Bio explains: "GasAbate N+ has the potential to transform how agriculture manages manure, greatly reducing GHG emissions and turning this perceived waste into an economic asset. Through its use farmers can dramatically reduce GHG emissions and require up to 28% less mineral fertiliser. This results in farm produce produced with a much lower carbon footprint, making such produce more attractive in the marketplace.
For AD plants the impact is transformative. This is a sector with extremely tight profit margins. By greatly increasing biogas output, productivity is increased with greater profitability seen, transforming the economics of AD. This is a topic of great environmental and commercial interest. We have had much interest from large corporations, looking to understand how tradable carbon credits generated through use of GasAbate N+ can be used to offset emissions generated."
Following funding from the Horizon 2020 EIC Accelerator programme and ERA-NET, the company expect to commence beta-testing of the product in autumn this year, with commercial launch in 2022.