Can someone please advise me where to go to get an ejector designed which must perform under the following conditions.

The ejector must transfer dry milled silica (40 um or less) from one pressure vessel to another. Both vesseles are at 70 bar / room temp. The vessels are connected such that they both held at nominally the same pressure but they are about 100 m from one another.

The milled silica is to be transfered via pneumatic conveying. An ejector / metering device will be located inside one of the vessels to convey the powder into the transfer pipe. The ejector will be fed by an external high pressure air source (>70 bar). Air will be bled from the second tank to maintain the pressure at 70 bar otherwise the pressure would obviously rise due to the addition of air which is fed to the ejector.

The reason for this request is that there are many designers of ejectors who are used to conveying at lower pressures but I haven't found any with experience at 70 bar and who might have knowledge of momentum transfer to the powder at the associated far higher air densities.

Any tips or advice would be welcomed. ■