You are right, Stephen- see e.g. http://en.wikipedia.org/wiki/Peristaltic_pump (and many leaflets)
Have used such pumps mainly for agressive liquids as HCl that corrodes almost all metals. But also for liquid cyanhydric acid (no problems) and for liquefied phosgene - great trouble had to neutralize a lot of this stuff- with gaseous ammonia- very unpleasant. A good choice for the Italian setup, I think. On Tue, Jan 18, 2011 at 4:50 PM, Stephen A. Lawrence <sa...@pobox.com>wrote: > > > On 01/17/2011 11:24 PM, Jed Rothwell wrote: > > Peristaltic pumps are an example of technology that by rights should > > not work, but they managed to pull it off. They overcame what seemed > > to be insurmountable problems with plastics. You have a wheel pressing > > down and squeezing the plastic tube thousands of times an hour for > > weeks or months. Early plastics quickly became brittle and broke. I > > don't recall who did this, but I read about it and I got the > > impression that person really, really, REALLY wanted to make > > peristaltic pumps work, driven by some inscrutable inner desire. > > I have the impression that pumps like that are really good for pumping > whole blood. Anything with an identifiable impeller also has edges > inside, and tends to cause clots. If you can get away with nothing but > a smooth tube, you can -- maybe! -- avoid ripping platelets and forming > clots inside the pump. > > But I have no idea where I might have run across that information... > > > > > - Jed > > > >
