Economic advantages of separating slurry

How can slurry management costs be reduced?

Slurry is normally used as organic fertiliser that is directly spread in the fields. This management system requires a few hectares of land, which are increasingly harder to find, especially in areas with high concentrations of livestock, thus increasing transport costs due to the need to travel greater distances. On-site separation of the liquid and solid phases of the slurry means the same amount of slurry can be managed on up to 20% less land, and money can be made from the solid phase.

What are the advantages of separation?

It can obtain up to 30% of dry matter. The solid phase is odourless and takes up to 20% Total Kjeldahl Nitrogen (TKN), 50% Total Phosphorus (TP) and 20% Potassium (K) from the original slurry. This means the solid phase can be composted or burned as fuel, sold and transported over long distances at a low cost. Meanwhile, the liquid phase requires smaller slurry pits and does not produce scale, making it more homogeneous. It can be treated by physicochemical or biological methods for disposal into rivers, application directly onto fields or dilution in irrigation water, and is much easier to pump and apply. When being applied to fields, it does not create scale and filters into the soil more easily, thus avoiding run-off and requiring 20% less field area.

TecnaPur by Rotecna

With its philosophy of providing farmers with high added value solutions, Rotecna has decided to broaden its horizons by creating a new line of business aimed at on-farm treatment of slurry. TecnaPur is a slurry separator made totally out of stainless steel that performs the three basic operations of filtering, pressing and scraping in a single system. TecnaPur has a large filtering surface that can treat up to 20 m3/hour (depending on the amount of solids) and consumes less than 0.75 kw/hour. It operates automatically, needs very little maintenance and does not require specialised labour.

How does it work and what advantages does the TECNAPUR separator offer?

A pump drives the slurry to a chamber with a flow controller that can be adjusted to the density of the slurry to be treated, so the same system can treat either very thick or very liquid slurry without the need for pre-filtering ramps to concentrate liquid slurry with low solid content. This reception chamber is fitted with an exclusive patented unwanted plastic and solid retention system, meaning there is no need to fit grinder pumps, thereby generating high quality compost that does not contaminate the ground with plastics from ear-tags, catheters, etc. The slurry then passes through a unique, innovative and patented double press and scraping sieve system with round holes that filters out animal hair (possibility of 500 microns at 2 mm), separating up to 55% of total solids (TS).

The pressing and scraping system (with no need to add water to prevent the sieve from getting clogged) is adjustable, and made of plastic, so there is very little friction against metal parts, thus ensuring high durability and low maintenance sieves and scraping and pressing system. All of this is powered by a single 1 HP motor, making the TecnaPur Separator one of the lowest consuming and most efficient separators on the market.

*Liquid fraction:
- Once the separation has been performed, there are no odours.
- The liquid can be used for irrigation (sprinkler or drip, pre-mixed with water) or fertigation, depending on its composition.
- Reduction in slurry pit volume. - Can be stored in slurry pits without forming scale and improves homogenization.
- Easy loading with barrels.
- Can be treated afterwards for dumping into rivers using physical-chemical or biological systems.
- Enables increased animal population on the farm

*Solid fraction:
- Between 20% and 30 % of dry matter.
- Highly manipulable and easy to store.
- Easily recoverable as compost. Highly appreciated as organic fertilizer.
- Use as fuel.

ADVANTAGES:
- Can treat both high-density (large amount of solid matter) and high-liquid (little solid matter) slurry.
- Does not need grinder pumps in order to operate.
- Does not need pre-filtering ramps to concentrate liquid slurry with low solid content.
- High-volume separation due to large filtering area.
- Machine performs the three basic operations: filtering, pressing and scraping in a single system.
- High-performance solid-liquid separation, since it uses a round-hole sieve with a very small surface area, which enables reduction of up to 55% total solids (TS), 20% nitrogen total Kjeldhal (NTK), 50% of total phosphorus (TP) and 20% potassium (K).
- No blockage due to adjustable brush cleaning system.
- Retains most pig hairs and expels them with the solid.
- Exchangeable stainless steel sieves with option of different hole diameters.
- Scraping and pressing system with plastic finish in contact with the sieve, so there is no friction between metallic parts.
- High durability sieves and scraping and pressing systems.
- Low power consumption by the separator (0.75 kw/h), which together with a small 0.75 kw/h pump means it can be used on farms with low horsepower electricity.
- Does not require specialized labour for operation.