Slurry Store Options
A slurry store is an essential part of an overall slurry management system, and is one of the most important, yet easily underrated items of slurry equipment. At Tramspread we supply a number of slurry storage solutions for clients across the UK, based on nearly 30 years of experience in understanding the variety of problems that face farmers when storing slurry for different purposes. Here we take a tour of the options and describe the pros and cons of each.
Why Does Slurry Need to be Stored?
To help us understand what is needed from a slurry store, it's useful to review the reasons why it needs to be stored at all.
A store is needed because slurry and digestate can only be applied at particular times of the year or at particular stages of a growing cycle. But livestock produce manure constantly – so it would need to be stored somewhere until the time is right for it to be applied.
Reception pits are an initial form of storage, but they are generally quite small, so they tend to fill quickly so the contents have to be removed to a larger volume store until it is ready to be applied. This creates a need for some type of storage away from the animal quarters.
Another reason for requiring a slurry store is if the slurry is not produced on site but is delivered (e.g. a farm which is wholly arable based, with no manure-producing livestock from which to generate slurry). Again, timing issues are important and a farmer may not be able to apply delivered slurry immediately, perhaps due to the current stage of the crop, or perhaps weather conditions.
One of the most popular types of slurry store we supply is the slurry bag – in particular, Albers Alligator Winbags and Bagtanks. These are flexible bags made from strong polyester fabric which has been coated on both sides with a plastic, waterproof layer.
Winbags, also known as Nurse Bags or Nurse Tanks, come prefitted with valves for filling and emptying and are available in a variety of sizes from 100m3 to 350m3.
Bagtanks can house larger volumes up to 7000m3 and are fitted as standard with fill/empty pipes and mixers.
- Nurse Tanks are a quick option if there is no time to construct a permanent tank. This allows a farm to start making use of slurry very quickly.
- These can be easily rolled up and removed, so they are ideal for farms which want to experiment with using slurry, or want to apply slurry only occasionally, without committing to a permanent storage facility.
- The slurry is fully contained, which improves safety and eliminates issues with odour and emissions.
- The slurry is covered at all times, preventing dilution from rain, evaporation, contamination or crust formation.
- It can be placed on any reasonably level surface, so no construction is required.
- No planning permission is required, so this may be a helpful solution if a farmer is not permitted to build permanent tanks (although all regulations about positioning of slurry stores still apply, however).
- It is considerably cheaper than other options?
- Nurse tanks take up more land surface area proportionately to volume than a raised tank, but this is probably a minor issue for most farms.
- Slurry bags don't have as long a lifespan as a permanent concrete tank.
- A Bagtank requires excavation of the ground to form a shallow pit to support the bag.
Slurry tanks are typically circular, concrete constructions, set upon concrete foundations and can be several metres in height. They may be covered or uncovered as preferred, and have fill/empty pipes installed at the time of construction.
- Slurry tanks can hold large volumes up to around 7000m3 although smaller tanks are also available.
- They are permanent structures with an extremely long lifespan. For instance, the Agri-Tank Concrete store supplied by Tramspread (pictured) is designed to last a minimum of 50 years.
- They provide good containment of contents with very little risk of leaks.
- They can be sited anywhere (subject to general requirements for all slurry stores).
- They can be covered fully to prevent odour issues, as well as for safety and to prevent crust formation.
- In the case of the Agri-Tank store, its prefabricated, modular design means quick installation on site.
- Tanks are more visually prominent from a distance than bags or lagoons, so siting needs to be carried out sensitively depending on location.
- Although planning permission is not always required it is always advisable to consult the local planning authority before beginning construction.
Slurry Pits and Lagoons
This type of store is essentially a wide pit, dug into the ground. A lagoon may be "earth lined" or "earth banked" so the slurry makes direct contact with the earth; or it may be lined with plastic or rubber, so the slurry is contained and does not make contact with the earth. This option is typically chosen for very high volumes of slurry, with some lagoons often measuring tens of metres across.
Tramspread do not supply or build slurry lagoons, as these are dug into the ground rather than constructed – but we can help with covers to prevent plant growth, evaporation, emissions etc.
- The biggest advantage is their virtually unlimited size, enabling storage of very high volumes.
- Slurry lagoons can be any shape, providing flexibility for farmers depending on the available land.
- They don't impact visually on the landscape to any great degree.
- Stirring is easy with a simple slurry stirrer attached to a tractor.
- Lagoons can be cheap to build.
- Earth-lined (i.e. unlined) lagoons offer a risk of ground contamination and environmental damage, which has to be carefully monitored.
- Safety measures are required around the perimeter of the lagoon.
- The wide expanse of most lagoons presents a challenge in terms of covering the slurry to prevent contamination, dilution, evaporation or crust formation. However, Tramspread provides a solution to this problem in the form of the Hexa-Cover, a floating cover which can be placed over the surface.
Slurry Store Specialists Tramspread
As specialists in slurry management Tramspread can help you decide on the best option for your farm.
Slurry Store – Find out more about our slurry storage options.