Spitfire managing director Stuart Reid says an effluent pond, pump and irrigator must work together to spread effluent uniformly.
“If the pond is poorly mixed or the pump delivers variable flows or the irrigator application is uneven, the system fails. You’d fire your fertiliser spreader if he did an uneven spreading job, so why be tolerant of substandard effluent spreading systems?”
Radial arm jet mixing involves one big submersible pump in the middle of the pond, with ten big nozzles blasting the solids. It’s always rotating just above the bottom to mix completely.
Because there are no propellers, there is no risk of liner damage. “And there are no sludge islands, no residual solids and no loss of operating volume,” Reid says.
A low speed cutter slices solids to size; there is no need to move tractors or direct agitators. The jet mixer is automatic, drawing power of 8-11kW. The operator has access to all nozzles and the pump even when the pond is full.
“Every drop of the pond goes out through the irrigator mixed uniformly. The pond, the pump and the irrigator work together to apply a uniformly consistent brew.”
Effluent is pumped from the pond with the help of a progressive cavity pump with programmable logic control.
It’s mounted onshore and there’s no need for a pontoon in the effluent pond.
The pump shuts down after detecting open hydrants, sudden hose disconnections, over-pressure and under-pressure operation. It handles lumps up to 8mm.
A visual displays keep farmers and workers up to date during operation. “Alarms tell you what happened and what to look for, in plain English, making fault finding easier. Equipment monitoring shuts down the pump and irrigator when things aren’t right.”
The third component in such a system is the new Spitfire irrigator – “intelligent” and simple to operate, Reid says. “You choose how much liquid you want to apply and it uses the on-board electronics to deliver liquid uniformly to the pasture. It’s like having an extra person on the farm devoted to effluent irrigation.”
Reid says the new FDE standard puts pressure on the irrigator manufacturer to ensure even spreading. “But it says nothing about the thoroughness of mixing and not much about the need for consistent pump flows. Integrated designs are really necessary.
“Jet mixers are here—just like a powerful Jacuzzi. No propellers, but always a homogeneous mixture at the irrigator. Cheaper than separator systems and all the solids and liquids leave the pond together. No solids spreading tasks remain.”
