Getting slurry to storage, as quickly as possible, helps to reduce ammonia emissions (and, therefore, nutrient loss) by limiting the contact time slurry has with air.
Key benefits:
- Retained nitrogen for spreading
- Improved hoof health
- Safer environment for workers
The use of satellites can enable the farmer to measure grass quantity and quality to be able to make informed decisions on grazing/harvesting. Allows for the early indication of weeds or disease in crops/pasture. Informed decisions on nutrient management and application can be made from satellite imagery.
- Allows the farmer/grower to cover larger areas of land
- Decisions can be made using data for harvesting/grazing
- Increased quality of silage and grazing
14) Regenerative agriculture
Changing from conventional farming practices to be more sustainable and enhance the natural environment. Practicing min till, incorporating rotational grazing into the system, establishing multi species pastures.
- Decreases farm carbon footprint and GHG’s
- Potentially decrease farm running costs
- Enhancing and looking after natural environments
Liquid from primary separation is stored in storage tanks for further processing or slurry spreading/irrigation. Reducing the bulk volume needed for storage is important to prevent the need for increasing storage capacity. Covering slurry stores also reduce ammonia emissions and prevent volume increase from rainfall.
Other benefits
- Nutrient retention – less nitrogen is lost
- Covering produce less smell and prevent rain from entering the store
- Better use of nutrients
- Potentially increasing yields
- Reducing pollution
- Minimise environmental impacts
Yards and passage ways contaminated with slurry emit ammonia, and should be scraped and washed down after each use. This dirty water must be included within a slurry management system. Harvesting rainwater or recycled water can be later used as washdown water, and also limits the amount ending up in dirty yard areas and, therefore, the volume of slurry for storage.
Other Benefits:
- Minimised pollution risk
- Reduced volume for storage
- Improvements can reduce labour costs and water bills/usage
- Safer environment for workers
Once the suspended solids in the slurry are bound together, a decanter centrifuge is used to further separate the slurry into a solid and liquid portion. Secondary separation allows for the capture of finer particles and nutrients. The produced solids are then taken to the solid store, whereas the liquid is sent for polishing.
Other benefits
- Enhanced nutrient capture
- Reduced volume for storage (compared to raw slurry)
- Solids are easier to store than liquids (stackable)
Liquid from the decanter centrifuge enters a Dissolved Air Flotation (DAF) unit. The process works by dissolving air under pressure within water, and, when that pressure is released, small micro bubbles are formed which come into contact with solid particles, sweeping them up to the surface where they form a sludge blanket. The resulting liquid can then either be sent to our reed bed, drip fertigation/irrigation system, or the AOP.
Other benefits
- Enhanced nutrient capture
- Reduced turbidity (colouration) in the liquid portion
Our project partners Natural Resources Wales (NRW) and Welsh Water / Dŵr Cymru, monitor and verify all of our water quality and treatment sampling.
NRW's purpose is to "pursue sustainable management of natural resources” and “apply the principles of sustainable management of natural resources”.
Dŵr Cymru / Welsh Water is a not-for-profit company which supplies drinking water and wastewater services to most of Wales and parts of western England that border Wales.
Precision/intensified soil sampling and the zoning of different soil types allows for a holistic approach for nutrient management on a field by field basis. When all the data is put together it allows field maps to be created that are then used for the variable rate application of nutrients. Variable rate applications can be done with the solids, slurry and manufactured fertiliser applying the right amount in the right place at the right time.
- Reduction of fertiliser bills
- Better use of the on-farm nutrients
- Increase in quality of silage/grazing
- Increased grass yields grazing/silage
12) Precision application
Moving away from splash plate applications of slurry to dribble bars trailing-shoe and direct injection reduces the amount of nutrients applied at each application. Roughly 20% of nitrogen is recovered when using splash plate spreading when compared with the use of LESS methods (Low Emission Slurry Spreading)1 where dribble bars lose only 65% and direct injection around 50%. These alternate methods of slurry spreading have a massive positive impact on air quality.
- Less nutrients lost
- Less risk of contamination of slurry in the silage/grazing
- Reduced slurry odour
In a reaction tank, we add two forms of coagulants/flocculants which are widely used in the water treatment industry. They help bind the most of suspended contaminants (including NKP) within the slurry together to make it easier for separation. Nevertheless, there are other chemicals which may be more suitable for other slurry types (e.g., poultry/pig), or this step may be skipped entirely dependent on your needs.
Other benefits
- Enhanced nutrient capture
- Reduced turbidity (colouration) in the liquid portion
- Drier solid portion during subsequent separation
18) Chemical Optimisation
Aquatreat based near to our main Campus in Llanelli are helping us with the optimisation of chemical selection and dosing rates.
N2 Applied have developed a system to be able to add nutrients to slurry and decrease losses to the atmosphere. By incorporating air, electric and slurry they lower the pH of the slurry and increase ammonia that is available to plants as nutrients. Methane emissions can be decreased by 99% and ammonia by 90%2. Trials conducted by ADAS showed that plasma treatment could retain 90% or more of the nitrogen when compared to slurry/digestate that had not been through the N2 applied process (3).
Key benefits:
- Potential of being self-sufficient in nitrogen
- Can be applied to slurry or digestate
- Decreased fertiliser bills
- Less loss of ammonia
- Crop yields increased up to 40%
The start of our dewatering process, feed is taken from the raw slurry pit and put through a screw press. The produced solids are then taken to storage, while the remaining liquid is pumped into the slurry store. There are a number of primary separators which can be tailored to best suit your needs depending on the type of bedding you use.
Other Benefits:
- Reduced volume for storage
- Solids are easier to store than liquids (stackable)
- Direct cost savings by reducing the need for spreading contractors/labour
- Low maintenance and cheap running costs
Developed by our partner Netafim, fertigation is the application of both water and fertiliser via drip irrigation. Drip irrigation is a system of plastic pipes that are subsoiled 200mm into the ground at the actively growing crop root zone. The combination of fertigation and drip irrigation presents many benefits to the farmer/grower.
Key benefits:
- Reduced nutrient losses
- No foliar contamination
- Quicker turnaround times for harvest/grazing
- Increased yields at times of drought/lower rainfall
- Reduced soil compaction due to less traffic
- Possibility of less run off of nutrients
Our constructed wetland is an engineered system that use natural ecological process of plants and microorganisms (biofilm) to remove a number of pollutants (including pathogens, nutrients, and heavy metals) and reduce chemical oxygen demand (COD). They have been used in traditional farm management for decades, however, what makes this design different from a standard system, is the inclusion of forced aeration. Once treated, water could then be used for washing down the yard (within a circular system), potentially discharged into a watercourse (if meeting discharge consent requirements), or, we are currently assessing whether it could be re-used to fill the cow troughs.
Other benefits
- Removal of final contaminants in wastewater
- Acts as a space for wildlife to flourish
9) AOP
Ongoing research and development for the incorporation of an advanced oxidation process (AOP) is being conducted our partner, Power & Water. In practical terms, this would provide a similar function to the reed bed albeit with near-instant results. In theory, the process aims to break the chemical bonds of recalcitrant molecules by means of chemical oxidation into less harmful substances.
Other benefits
- Removal of final contaminants
- Acts as a space for wildlife to flourish