let s discuss Russian vacuum drying chamber

[serg]

Stevareno, Hi! Well that you have understood a basis of technology of vacuum drying under my diagram. Such mode will give better quality of an oak of any thickness. Food for dogs I dry other diagram. 760 mm temperature 50Ñ, fiber alive, then quickly vacuum of 75 mm. The explosive method turns out, the food is increased in volume, color does not change, dries quickly. The pair much, was necessary to change a design a little. Such diagram for an oak poorly! Serg

[serg]

Board, wood an oak one piece, the beginning of 70 % 65*120, the end of drying a board the centre 6 %-edge(territory) of 5.5 %. A package, a stack of 8 meters cubic an oak, 65*120 beginning of 70 % the end of 5-6.5 %. 10 points top, the end started the centre a package, a stack of 1.5 % (5-5.5-6.0-5-5 %%)

[Den Socling]

I just reread this whole thread. It's still hard to follow even now that I know what's going on. Serg and I have had some private email exchanges. Stevereno does a good job of translating. (But he's a recent graduate in a crash course in vacuum drying.) I don't agree with Don. 340 kW/m3 is not far from the cost of drying Oak from 70 to 6% in a DH kiln. But the real kicker is this: Ole Sergey has a good idea that appears to work. It's slow compared to our kilns but it's cheap compared to our kilns. I told him to quit telling people how it works and I even thought about removing this thread.

I'm talking to Serg. I'd like to tell you how to make a kiln as good as the discontinuous vac but easier to build but, naturally, I'm not going to violate Serg's trust.

the plot thickens................

[Tom]

Don't worry Den.  I've studied this thread and studied this thread and still can't make heads or tails out of it.  You guys are alright.  It's a good thing you speak that drying language, It's the only communication that seems to be working.

Y'all go to it, do it right and tell us what happened one of these days.

[serg]

Den, Hi! You can make devices of drying under my diagram

[rerednaw]

1.Serg, on some russiam forum and on you site you tould what you dont use any computers or microprocessors and what user of you kiln no need to spend all day and night to control process. But also you tould what you start you process from pressure 0.04Mpa and 45 C and pair humiduty near 60%, then pressure down to 0.09Mpa, temperature up to 70C, after 30% wood MC, pipe with could water is closed to keep humiduty near 100%. I see it's to hard to understand how you control all of this without operator or computers ? maybe you use timers ?
2. As i understand you kiln is easy to build on backjard and from backjard parts. Can you (like Den) help to anyone who want make his own kiln working by you method ? and by this all of us will better understand how this things work (if you realy want it) I think you system is a little bit easy to build, but im not sure what it is easy to control

PS: 0.04 mean 600 mbar absolute, 0.09 mean 100mbar.

[serg]

1. Yes, on the russian forum and and on my site i explain what is it possible to dry wood without any computer programs, especially in Russia, but my techlogy can be computerised if someone want this. in my kiln i use cintrol panel wich contain wood moisture metter (2 pcs), sensor-regulator air temperature in kiln, and vacuum pumps relay. For first phase operator must set temperature 45C and vacuum -0.04 Mpa and end wood moisture for stop process 30%. for second phase operator must set tempereture of air near 65-70C(depend of wood thickness), close condensing pipe with could water and vacuum -0.09 Mpa. and stop wood MC at 4-5%  This need becose at wood moisture 30% wood have to change  inside  effort and we need to steam thoroughly wood to free wood of effort. Why i stop when oak MC is 4-5% but not 6-12% ? Becouse at 12% the lossing of weight in ekspluataion is near 3.1%, at MC 6% - 0.8%, and at 4-5% - 0.0% and we can produce any furniture without quality degrade 2. i help to many people to make his own vacuum kiln. draft, techology, teacing. all satisfied  all for the common good. Saving time, money, no transport paymnet. drying from 100% MC.Serg

[Fla._Deadheader]

  I have been too busy to try to follow all this Russian technology. I never completely figured out the conversion rates of vacuum and temps.

 Den, how different will Serg's ideas be, compared to your ideas, for the dis-continuous kiln you were going to help myself and Shopteacher to construct???

 I am about ready to start the chamber upgrading and want to use the simplest way to dry the wood. We will have limited access to electricity, for monitoring.

 I don't want to break the trust of "secret" info, just keep us on the right track, so we can do our drying and share results with the others that may be interested.  A design change would be MUCH easier before starting to build the door and vent tubes.  Thanks

[Den Socling]

Well, since Sergey says it's OK, here's what I see. His design is something like a discontinuous vac kiln. He has heating water pipes running back and forth on the bottom half of a cylinder. This next part is a new idea and I think it's a good one.  

Sergey,
Are you positive that it's OK to tell how you get convection?
Den

[Fla._Deadheader]

  Here in Fl., I believe we can use Solar heated water, if we need it. Just setting out in the sun will heat the chamber year round down here.

 I am wondering about the cold water  

[serg]

I measure temperature of air in kiln. when we reach T in kiln wich we need we
stop heating. at this stage very impotant is how good you thermal
isolation around kiln. by isolation you can save elektricity. our
record is 7.5kw per hour. Vacuum we measure by mechanical vacuumemtr
(some old models with arrow Our process is at _continuous_ vacuum.
vacuum pump work only 2 times for 20 minuts at all drying process.
operator nedd to take care of kiln 1 time in 2 days. is no problem to
connect computer to this, but we think what is only money waste

oak need respect to himsel, only in this case we will dry oak in very good quality. oak is wise when people, it live 300 years, and dont like quick and rigidity. We take kare about oak at philosophy point of view.

[serg]

Yes, it is possible to heat water the sun economy of an electricity

[serg]

Movement of air in the vacuum chamber exists in three variants, and all three variants are present during drying. The first idle time, a cold falls downwards in a crack between a stack, warm air rises in top. Other the secret has two. Drying very strongly depends on stacking a stack.

[Den Socling]

Well, there he goes.  

First, he doesn't pull low pressure (strong vacuum). He starts around 450 Torr. This leaves enough air for convection. Then, condense top, dead center. Catch the condensation in a trough. Leave a gap in the kiln charge for the cool air to fall into. Heat on the sides will pull it through the stack, pick up moisture and send it back to the top, heated. Brilliantly simple. I may build one, myself.  

[Fla._Deadheader]

  What would 450 Torr equal in plain language??? Is there a conversion chart for us that don't understand the terms

[Den Socling]

The weight of the atmosphere is close to 760 Torr. In outer space, with no air, pressure is close to zero. So, with 450 Torr, less than half the air is removed.

[serg]

Den, hi! My vacuum chamber economically can work in Florida

[Fla._Deadheader]

  Yer gonna force me to go to school to learn the terms, ain'tcha

 How am I supposed to know when the chamber is half full or half empty of the cubic volume of air

[serg]

The device will show 0.05, it is equal 50 % of air in the chamber.

[Den Socling]

You know diving, right. Think you can tell the difference between 5 feet and 20 feet? It's the same with air pressure. It has weight just like water. Here at the bottom of the ocean of air, there is 760 Torr of pressure.