Aeration pads operate at 10 psi and are designed to aerate or fluff the cement for flow.  The air needs to be dry and clear of any oils or lubricants.  Early plants used the plant air compressor (95 psi) for the air supply to the aeration pads via regulators to reduce the air pressure to 8-12 psi.  Plant air compressors  incorporate an electric pump and pressure tank to supply the plant air needs.  Compressed air generates pressure and heat, that has moisture, that in turns can condense overnight when the plant is not in operation.  The condensation in the tank can collect enough to produce moisture/water in the tank.  The water in the tank can cause corrosion in the solenoid valves and plugging of the cement aeration pads/nozzles.  Draining the air compressor each night and leaving the petcock valve open will help eliminate this problem.  Water traps should also be standard items on any concrete batch plant pneumatic system.

Modern Concrete Batch Plants include dedicated aeration blowers for the cement aeration pads and air slides.  These blowers are low pressure (15 psi) , high volume (150 CFM).  Typical Blowers are 5HP and 7 HP.  A typical assembly drawing incorporates a 2" pipe manifold with individual air lines ot each aeration pad.