I did some research on organic coolants for nuclear reactors a while back. The idea was to replace the typical high pressure high temperature pressurized water reactor coolant loop with a high boiling point organic oil loop operating at low pressure (below atmospheric to reduce the chance of contaminated coolant leakage).
The best oils I found for this application were based on Polyphenyl mixtures and sold under the trade name of Santowax. There were two types, Santowax R and Santowax O-M. O-M is more costly as it contains more Diphenyl and o-terphenyl but has a lower melting point of 125F, so it would be fairly easy to keep it from freezing. As I recall these oils are quite stable to over 600F (even in the extremely hash environment of a rector core). I don't know if Santowax is still readily available. Dowtherm looks like it has a similar chemical composition so is probably the modern equivalent. I think you should seriously consider using an oil instead of water, as the advantages are manyfold. The boiler would not need be built so ASME standards, and in fact could be open to the atmosphere if desired. The circulation pump would only have to be rated for hi temp, and the piping system would be greatly simplified by being able to use common low pressure fittings such as swivels, quick connects etc. which would likely an advantage given the application. Also corrosion would not be a concern. Anyway, my $0.02 Cheers, Kurt *Kurt Jacobson, CMfgT* Mechanical / Manufacturing Engineer Center for Nuclear Studies | Southern Polytechnic College of Engineering Kennesaw State University | Marietta Campus E-mail: kurtcjacob...@gmail.com On Wed, Feb 8, 2017 at 2:45 PM, Jim Craig <jimcraig5...@windstream.net> wrote: > Syltherm or Dowtherm are just such oils that are used in heat transfer > applications. Dowtherm is used in thermal solar power plants. There are > others out there but I cannot remember them off the top of my head right > now. > > If the right one is selected they would be much more stable at 280°C > > Jim > > On 2/8/2017 12:24 PM, Todd Zuercher wrote: > > What about using some sort of oil, or some other liquid that would not > have the high vapor pressures of water? > > > > > > ----- Original Message ----- > > From: "Chris Albertson" <albertson.ch...@gmail.com> > > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net > > > > Sent: Wednesday, February 8, 2017 12:49:16 PM > > Subject: Re: [Emc-users] OT: Need some guidance on high temp/pressure > water circuit > > > > The only thing I know about this is that you absolutely need to keep air > > out of the system. It all needs to be designed so that trapping air in > the > > plumbing is impossible. When/if the plumbing bursts having compressed > air > > inside makes it a lot more dangerous. > > > > > > > > On Tue, Feb 7, 2017 at 3:30 PM, Leonardo Marsaglia < > > leonardomarsagli...@gmail.com> wrote: > > > >> Hello to all! > >> > >> I'm in the process of designing and planning a system to rapid > >> heating/cooling a mold for plastic injection. The project is still in > the > >> board so I think it's a good time to ask help from you guys. > >> > >> I'm trying to make the system as simple as possible so I'll tell you > what I > >> have in mind and what are my doubts and concerns. So here it is: > >> > >> A high pressure vessell with resistors is what I'm planning to have as > an > >> accumulator and heating device. (The vessel should have pressure relief > >> valves and maybe a rupture disc). The idea is to reach 1000 PSI (to > avoid > >> water to start boiling) and 280°C. From what I've been reading the best > >> pump for this cases is a gear pump because it can handle better the > thermal > >> dilatation of the components. > >> > >> My main concern is, at the inlet of the pump the pressure is going to be > >> 1000 PSI, and I have only worked with pumps at atmospheric pressure at > the > >> inlet side. Is this going to be a problem? The differential pressure at > the > >> output is intended to be 50 or 100 PSI more than at the inlet just to > make > >> the water flow through the mold and return to the vessel. There are > going > >> to be valves to switch between cool and hot water. > >> > >> Also I may need to consider using special materials on the pump because > of > >> the corrosion, or may be some additives in the water, but my main > concern > >> is the rough construction of the system. I'm attaching a little diagram > >> with my idea just to start and discuse if it's doable or not. Needless > to > >> say I'm going to take every safety measure possible with this kind of > >> system. > >> > >> I would be thankful if you can guide me or tell me if this is too > >> complicated and dangerous to even give it a try. > >> > >> Thanks as always! > >> -- > >> *Leonardo Marsaglia*. > >> > >> ------------------------------------------------------------ > >> ------------------ > >> Check out the vibrant tech community on one of the world's most > >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot > >> _______________________________________________ > >> Emc-users mailing list > >> Emc-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > >> > > > > > ------------------------------------------------------------ > ------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
