From what I can work out (since Victor needs a translator, not just any language differences) is he's trying to suggest that you could create a "perpetual energy" device by ejecting compressed air through a turbine, capturing it after it's been used, re-compressing it on the other side of the turbine and then ejecting back the other way to repeat the same capture, re-compress and eject method.
(In essence it's a similar concept to a piston engine, however instead of combustion he's using compression and instead of piston assembly he's using a turbine.)
The problem with his current model is it violates a number of physics laws (Notibly a number of Newtonian Laws) that aren't just written by boffins in white labcoats, they are actual universal laws which the universe functions to, so they aren't easily bent or broken.
People have already stated where Victors "Propellant VEEG" fails before he even does a test, for instance Capturing an ejected propellant after it's been through a turbine and re-pressurising it is going to cost energy, probably more than what is made from turning the turbine.
There is then the point about the Orifice used for ejecting a propellant stream, the size of the orifice has an effect on the efficiency of how much pressure can be pushed through it, if it's too small then it won't be a high enough volume to push a turbine, if it's too large then there won't be enough force to push the larger volume.
Temperature would also play an important role as even in a closed system since it's dealing with "Gas" and it could alter whatever results would otherwise exist. (For instance Aerosols usually have a temperature warning because they have a set design limit on how pressurised the container should be, if the temperature goes about that the Aerosol can burst. Some people have had this happen in their cars and it can cause a lot of damage.)
I know I can say "Victor I really don't think it will work", however it's not going to stop him trying if he is absolutely sure that he's right. He'll only be able to learn by seeing it for himself, I just hope he's capable of being able to see a prototype not produce the results he wants and still be happy he tried.