Pneuma System: Technical

The principal characteristic of the PNEUMA System plants, operated by compressed air, consists in the lack of rotating parts, or any type of mechanism, in contact with the mixture to be pumped. By gravity, the liquid passes through the external valves, which function automatically, and enters alternatively into the pump cylinders forming the pump body. From here it is pushed through an internal delivery valve, without contacting the mechanical parts placed on the surface.

The plant is formed by:

a) Pump body, generally consisting of 3 cylinders with no internal rotating mechanisms apart from rubber inlet and delivery valves. The pump can be equipped with inlet pipes (see fig. 1) or with. disaggregating and levelling shovels (see fig. 2).

b) Distributor, which regulates the influx and discharge of compressed air to and from each cylinder of the pump body and assures uniform functioning and a continuous flow.

c) A supply of air, generally produced by a compressor driven by any type of motor.

The compressor and distributor group are placed on the surface, even at a considerable distance from the pump body to which they are connected by compressed air hoses. In case of deep waters the distributor is placed on the top of the pump body.

The delivery and air hoses are completely independent from the rest of the plant.

The liquid fills the cylinder by the counter-pressure due to the level of the liquid itself or by a vacuum system utilised in very shallow waters.

Once the cylinder is full, compressed air, supplied by the distributor, acts as a piston.
Consequently the liquid tends to close the external valve and pass through the internal delivery valve.

After having worked in one cylinder, the compressed air is discharged through the distributor into the atmosphere.

The regulation of the distributor movements which automatically put the pump body valves into operation through the air pressure and the counterpressure of the liquid, guarantees the perfect uniformity of the flow.

The PNEUMA pumps, working due to the effect of the hydrostatic water column or of a vacuum system in case of shallow waters, can be considered a positive displacement piston pump, with compressed air taking place of a mechanical piston

The work cycle of the Pneuma pumps can be divided into three phases:

Phase one: Filling the pump

Each cylinder is rapidly filled with mixture by the counter pressure due to the hydrostatic head with the help of a vacuum system in case of shallow waters.
As soon as one cylinder is filled, the inlet valve automatically closes by its own weight.

Phase two: Emptying the pump and reflowing

When the cylinder has been filled, compressed air, supplied by a compressor through the distributor and air hose, acts as a piston and the mixture is thus forced out through the delivery valve.

Phase three: Discharging compressed air and preparation for Phase one
When the cylinder has been almost emptied, the distributor discharges the air into the atmosphere. Once the internal pressure is released, the cylinder once again becomes filled with mixture, as described in phase one.