Troy look to the electric smog pumps. We will now be using these on all future products These things are very powerful and are not passive they can build pressure like a turbo. We are no longer running any gas through our blowers as well. These smog pumps we are using now are capable of running an ejector and do a better job of it than an air compressor. The other method is to pressurize the system and again these things are way more than enough to do this. For now we are using a bypass valve and is perfectly fine, but if you want to eliminate the noise of the blower then consider a PWM. These are automotive so they are designed to live in the engine compartment. So are very tough, but I would still try and design a system where you gas is not touching the internals of it.
Edit: I didnt see your last post, yes infact we will pressurize all systems going forward. We use the ejector to put fire to the machines and then switch to positive pressure. Ive also been playing with boosting the gasifier under engine running. This is going to evolve to a full blown turbo on the Evolution machines we should see some power and efficiency gains by relieving vacuum loading.