An estimated 1,400 million tonnes of manure/ year is produced by livestock reared in Europe (Foget et al., 2011; Eurostat). The main source of slurry from livestock farming derives from cattle or swine. The 2019 UK Farm Practices Survey (FPS) reported that:
- 64% (+/-8%) of dairy farms had facilities to store slurry in a tank, while 53% (+/-7%) could store slurry in lagoons.
- 11% (+/-4%) of lowland grazing beef farms have slurry tanks, while 27% (+/-8%) of less favoured areas (LFA) farms had facilities to store slurry.
- 84% (+/-20%) of pig holdings could store slurry in tanks, while 42%(+/-16%) could store slurry in a lagoon.
As 55-95% of the nitrogen (N) and approximately 70% of the phosphorus (P) ingested by livestock are excreted through urine or faeces, manure is a natural and excellent source of fertiliser for the agriculture industry (Leip et al
., 2019). For example, approximately, 11 million tons of Nitrogen mineral fertilisers are applied to crops throughout Europe each year, the total manure produced by Europe contains 7 million tonnes of Nitrogen. Nitrogen, in the form of ammonia, is lost from organic manures (such as slurry and solid manure) when it comes into contact with air, particularly on warm or windy days.
Ammonia & Green House Gases (GHG’s)
Ammonia emissions from manure storage account for 9% of UK agricultural ammonia emissions, with 25% from the application of manure. In 2017, the agriculture industry was responsible for 10% of total GHG emissions for the UK, of which approximately 17.6% of GHG emissions was directly due to manure management practices (Agricultural Statistics and Climate Change Report, 2019). The introduction of Nitrate Vulnerable Zones (NVZ) and further changes in UK policy aimed at reducing GHG emissions in the agriculture industry has tightened rules on slurry management with a risk of penalties/ prosecutions should these rules not be met.
In the UK, covering the slurry store is a legal requirement if you operate a permitted pig farm. The Government’s Clean Air Strategy 2019 states that, in England, all slurry and digestate stores must be covered by 2027. In the UK there will be a requirement to spread slurries using low-emissions spreading equipment (trailing show, trailing house or injection) by 2025. Moreover, there will also be an extension of environmental permitting to dairy and intensive beef farms by 2025, to regulate ammonia emissions and limit pollution from these enterprises.
Options Available for Slurry Treatment
There are a number of different options available in the treatment of slurry, including:
How MicroZyme works
- Slurry acidification
- Slurry cooling
- Phase separation
- Anaerobic digestion
- Aerobic biological treatment
- Biological treatments e.g. MicroZyme from Micron Bio-Systems
MicroZyme is a biological treatment containing a unique blend of bacteria strains and enzymes specifically selected for their capability to break down fibre, starch, pectins, fats and protein (organic waste) residues.
Advantages of MicroZyme
Decreases solids and reduces crust formation, enabling shorter stirring times, less separation, fewer blockages, quicker pump outs for easier injecting or spreading, thus reducing application cost to the land with less surface run off risk.
Reduces ammonia and other odour emissions, benefiting the environment, handlers and those locally affected.
Helps preserve the nutrient (Nitrogen) content in the slurry, optimising its value as a fertiliser. Moreover, its increased and consistent nutritive value and consistency increases plant uptake, allowing slurry to be applied to multi-cut systems.
Populates the slurry with beneficial bacteria, lowering levels of unwanted coliforms e.g. E.coli
Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) levels are also lower. BOD and COD are chemical indicators of odour, used as a surrogate of the degree of organic pollution in water. The higher the value of BOD and COD, the more polluted the water and the higher the production of noxious gases.
Suitable and safe for use in organic systems.
From a Micron farmer survey sent out in 2021; 70% of farmers store slurry with 10% of customers using some sort of treatment on the slurry during storage, 15% used solid-liquid separation, 10% compost, and 5% use AD digesters. According to the Inventory of manure processing activities in Europe (Foged et al
., 2011) only 0.7% of the total liquid fraction of livestock manure produced is treated.
Different slurry treatment options are available (including acidification, filtration, phase separation, anaerobic digestion), however some methods require significant investment from the farmer, others do not provide a valuable resource that can be used post treatment and some even provide further environmental risk.
MicroZyme offers a scientific solution to lowering emissions, retaining nutrients and making handling of slurry easier, without the capital investment.
MicroZyme has two different formulations, one for cattle slurry and one for pig slurry:
Click for product information on MicroZyme R for Ruminants
Click for product information on MicroZyme S for Pigs
The Impact of Ammonia Emissions from Agriculture on Biodiversity, 2018
Evaluation of Manure Management Systems in Europe, 2015 https://core.ac.uk/download/pdf/46606176.pdf
UK Clean Air Strategy 2019
COPAG for Reducing Ammonia Emissions
AHDB Slurry Storage
The value of manure - Manure as co-product in life cycle assessment
Leip et al., 2019