A standard steam ejector-liquid ring vacuum pump combination set, good for pressures down to 5mbar abs.
The liquid ring pump is operated on a closed ring loop basis to reduce effluent, and the coolant medium is tower water at 25°C maximum summer temperature.
The vacuum pump produces 95% of the vacuum required for the process with the steam ejector boosting down to the final system pressure required.
With this hydrid arrangement, a suction volume of 500m3/hr of incondensible gases can be handled at an absolute pressure of 7mbar for a motive steam flow rate to the ejector of only 22Kg/hr.
There is no reasonable limit to the amount of condensible vapours that can be handled provided the that inerts are kept low.
Please click on the above image to see a larger version of the diagram.