WHEN FARMS set out to address a shortage of slurry storage capacity, minimising the volume of 'dirty' liquid generated by the daily routine is a good place to start.

Modifying drainage systems to collect dirty water, such as yard run-off and parlour washings, and channel them to a separate storage facility rather than the slurry lagoon or store, helps minimise volume. And, dirty water can be applied during the Nitrate Vulnerable Zone (NVZ) closed period when conditions allow.

But to really have an impact on the problems created by slurry, installing a separator is the most positive step to take. With the liquid fraction extracted and pumped to a lagoon, only fibrous material remains to store in bulk.

"Separating allows these different materials to be stored and applied to the land in the most appropriate way – and with minimal smell," says Adrian Tindall, of Bauer. "They will also provide more consistent nutrient analyses than slurry, so they can be applied at the appropriate rate to reduce reliance on bagged fertiliser, while conforming to NVZ restrictions where necessary."

Traditional methods of bulk slurry storage do not make it easy to properly utilise what a growing number of producers now recognise as a valuable commodity rather than mere 'waste' – especially as bagged fertiliser prices continue to rise.

"Extracted solids with 30% or higher dry matter can be stockpiled in field heaps where nitrogen losses will be lower than from slurry, in readiness for application ahead of ploughing for grass, maize, cereals or other spring crops."

Two types of separator are available: the large screen type with revolving rollers and brushes, and the screw type, which Bauer has produced for the past 25 years.

Bauer's established models, the S655 and S855, are supplied across the Central Belt of Scotland by McCaskie Farm Supplies. They use a 5.5kW motor, with the S655 able to tap into single- as well as three-phase electricity supplies. The S655 is rated to handle up to 20cu m of slurry an hour, while the S855 is rated at 30cu m/hr. A new 3kW model rated at up to 15cu m/hr is being added to the range.

• A working demonstration of a compact slurry separator for smaller farms will be the centre-piece of a display highlighting the debut of Bauer slurry equipment on the McCaskie stand at Agriscot (November 16, 2011, at Ingliston, Edinburgh).