I have a question related to flow of condensate and non-condensables in a 3 stage ejector system for vacuum.
We say that from each condensers (1st, 2nd and 3rd stage) there is a seal leg / barometric leg for transportation of condensed liquid to receiver vessel to overcome the pressure difference between condensers(low pressure region) and Receiver Vessel (Higher Pressure), however from 3rd ejector condenser the non-condensables are also routed to the same receiver vessel.
Having said that, how is it possible to transport non-condensable gases from 3rd Ejector Condenser (Low Pressure) to Receiver (High Pressure).

Thanks In Advance for Considering the above query.

Muhammad, the pressure In the 3rd stage condenser is atmospheric or slightly higher. Thus there In no problem in transferring the non-condensable. You must have a vent at the top of the condenser, this vent can be connected to the vessel through the barometric leg or directly in the pot. I hope I have helped you.

Mr. Edelson: Yes indeed your statement "pressure In the 3rd stage condenser is atmospheric or slightly higher" has certainly helped me.
I would be very thankful, if you could help in understanding how the pressure in condenser in at atmospheric or slightly higher.? If its at atmospheric than why there is a need of barometric leg for condensate flow to that same vessel where non-condensables are going.
Thanks for your kind interest.

Muhammad ,
is a pleasure to help, just excuse any mistake in English.
An easy way to understand is to consider each of the condenser as a stage of distillation , so we will have a vapor-liquid equilibrium at that pressure and temperature.
The second point to consider is the composition of the vapor phase, in the vacuum distillation processes typically consider the presence of air leaks coming from . If the seal system is perfect , so we need to consider the vapor pressure of the lighter component present . In those cases we have vacuum in last condenser.
Regarding the barometric leg in the third stage , it has two functions , the first is for the case of vapor pressures below atmospheric , the second is to send the products resulting from the condensation, which in your case should be water and hydrocarbons, to a vessel from which we can send it to a secure location . Correct?
Nowadays with responsibility for environmental problems is usual put a system of gas absorption in the vent vessel.
Feel free if you need more details

We dont have a gas absorption system, however these gases are labelled as Waste Gases and are routed to Heater of Crude Distillation Unit.
Thanks for sharing such a vulnerable knowledge.