Dairy Effluent Management: Right Amount at the Right Time
Good effluent management on a dairy farm combines a well-designed system with proper processes to ensure the right amount of effluent gets applied to pasture at the right time.
Yard washing, pumping and effluent screening gear will be on the GEA site at the Effluent Expo at Mystery Creek. The expo will be held on November 27 and 28.
At the milking shed, the Flush Valve offers quick and easy wash-down using high volumes of fresh water or recycled effluent (‘green water’). This has a 5.5m clearing width and the liquid is delivered in a horizontal plane with little or no splashing vertically.
The heart of the system is a valve actuated via a robust airbag system for opening or closing; it requires only 40psi to achieve a head of 8m.
It’s reckoned easy to install and maintain via large access panels.
The Agri-Pump, a dual-purpose unit that agitates and pumps, can handle effluents with high fibre or solids content to supply a constant flow of well agitated material.
Using a rugged propeller knife and impellor blade system, the belt-driven unit has a pump whose revs are easily adjustable, and a rotating nozzle (optional) deals with crusts or stagnant liquid.
The unit mounts on the side of the reception pit and is supported at the base; this siting allows easy maintenance. Its 3-way gearbox drives a propeller and an impellor, to agitate and pump from a common drive shaft. The cast iron impellor carries four curved blades to pump through a 100mm outlet pipe.
In many installations the pump flow might be directed to a GEA Slope Screen that separates the liquid and solid portions of effluent, reducing wear and blockages in pumps, effluent lines and irrigator nozzles.
The liquid portion can be held in a storage tank and re-directed for wash-down, saving clean water, while the solid content can be used as a fertiliser or soil conditioner.
In operation, the Slope Screen is mounted on a platform above a solids bunker, with a flow of untreated effluent directed to the top of the screen via a regulator valve. As the effluent moves down the screen the liquid passes through to a holding tank while the solids are collected in a loading bunker.
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