Iranian vacuum kiln

Den Socling · January 14, 2006, 03:10:07 PM

As I mentioned elsewhere, I have been corresponding with Dr. Behbood Mohebby from Iran. He had contacted me about vacuum kilns and has sent pictures of a kiln he has built. I thought some of you would like to see.

he's tryin'!

He also has a website. I just checked it and it's down but you should try to see it.
http://www.tmu.ir/wood
If you find it up, check out the trip to Farrahs Machinery or visit to Ferahs machinery or something like that. It's pictures of his kiln class visiting a conventional kiln installation. It's really a small world despite what the politicians try to do.

Den Socling · January 14, 2006, 03:21:41 PM

His website is up. Here's a link I would like to make.
http://www.tmu.ir/wood/TEMPs/Excursion-Afshar.htm
It is an excursion to Afshar's.

DanG · January 15, 2006, 01:01:36 PM

That's a neat looking kiln, Den. Is he using it as continuous, discontinuous, or does it work like Serg's rig?

Den Socling · January 15, 2006, 01:41:17 PM

It works kind of like Serg's kiln - like a 'steam vac'. Serg has enough vapor and air in the chamber for natural convection while Dr. Mohebby uses fans. You can see the fans mounted inside. That triangular shape on the outside is a belt guard for the fan pulleys. Notice also the two cylinder air compressor that he is using in reverse.

I'll invite him to join the forum.

serg · January 15, 2006, 02:29:43 PM

Hello!
I looked a site of the Iranian university. The information on quality of drying of vacuum is not present.
Den, you know that each drying chamber should dry all wood of the world qualitatively.
The result of drying gives the answer on quality:
1. W - % on length of a board ???
2. W - % on a stack top, a bottom, ???
3. W - % on thickness of a board ???
4. Is whether or not internal pressure(voltage) ???
5. Is whether or not internal cracks ???
6. Face cracks and the screw of a board ???
From the small information I have understood that they make updating a tree, bend it(him) at high temperatures? ???
The professor from Iran is desirable on a forum. :P
Sergey.

DanG · January 15, 2006, 02:43:39 PM

Please do invite him. That would be interesting.

I sorta figured that's how he's running it when I saw the fans. I'm beginning to think that may be the best way to go for guys like me, so we don't have to deal with such a large "absence of pressure." The equipment wouldn't be nearly as expensive.

Mr Hootie has a pair of tanks that would be great for that. They are 3' diameter and 32' long twin propane tanks from an old gas truck. They are welded together. Given their age and length, I'd be scared to pull them down to 28 Torr, but they may be ok at a lesser "non-pressure."

I see that Serg has weighed in while I was typing.

This is no longer a unilateral invitation for Dr. Mohebby. I hope he decides to join us in light of this International effort.

GF · January 17, 2006, 12:59:59 PM

Could you effectively vacuum dry lumber using a air compressor pump in reverse? I would be curious as to how much vacuum it could pull.

Den Socling · January 17, 2006, 03:39:38 PM

I have used a refrigeration compressor in reverse (meaning I connected to the suction side) and they will actually pull very low. A big problem, though, is water vapor getting in the oil. It makes a mess. If you ever looked at oil in an engine with a blown head gasket, you know what it looks like.

isassi · January 18, 2006, 07:18:47 PM

So I guess you would need a dryer or water trap of some sort? A regular dryer inline with a compressor, as in an automotive system would not work due to the large amount of water? Ok...I'll put on my propellor hat and sit and think...think think think... :

:

....headache beginning...what are other thoughts?

Den Socling · January 18, 2006, 07:39:57 PM

Two suggestions. 1) Use a liquid ring vacuum pump that is affected less by water vapor and 2) use a tube and shell heat exchanger standing vertically in the pipe to the pump.

Fla._Deadheader · January 22, 2006, 10:22:11 PM

Hi Den
We are gearing up to start building a vacuum Kiln in Costa Rica. Found some Propane tanks at the airport. I have some vane type vacuum pumps. We used vane types on milking machines, and they were subject to water vapor from the warm milk and cleaning the pipingsystem. If a solenoid activated Valve was used to hold the vacuum, would the pumps work well enough to at least be certain the kiln is functioning correctly ?? Figure on the dis-continuous method, so, not so critical onvacuum and such.

Any new suggestions as to construction ??

Is is cold enough in Pa. to warrant a trip to CR for ya ?? :D :D :D

Den Socling · January 23, 2006, 09:21:13 AM

If you want to hold vac (and I would), a ball-type check valve will close the pipe line when the pump goes off.

Soleniod actuated valves can be used for a variety of applications but we have shifted to actuated ball valves with spring return.

During most winters, CR would be looking good. But next week I'm heading to New Zealand for a couple/few weeks. When I leave NZ, I'm going to Hawaii for a week. By the time I get back to PA, it will be close to spring time.

Jeff · January 23, 2006, 10:54:59 AM

Den, I am an orphan looking for a good family to adopt me. :-\

Den Socling · January 23, 2006, 11:03:58 AM

Well son, it looks like you could be a big eater. :D

Actually, I've heard from a lot of orphans and volunteers lately.

Jeff · January 23, 2006, 11:43:25 AM

Well if big eater is a problem, I can diet. :D

Den, does your friend from Iran use the internet? Can he get on the forum? It would be interesting to have a forum member from there that can help us understand the business he is in and also as things unfold, an understanding of current events from his prespective.

Den Socling · January 23, 2006, 12:08:14 PM

Yes Jeff. I am trying to get him connected. I sent him a link and asked him to connect when he had time and he responded with his office ours. ??? But we're working on it.

Did you click on the 'excursion' that I linked above? His kiln class doesn't look like what many would expect. With current events, I like as many people as possible see our similarities.

serg · January 23, 2006, 12:30:44 PM

Hello!
I think the colleague from Iran wants to talk on a forum! :P 8)
But I know that such totalitarianism and censorship!

To live under a cap, bad idea. :'(
Sergey

Fla._Deadheader · January 23, 2006, 04:26:59 PM

Hope you enjoy your trip. I believe with the thread on dis-continuous vacuum, and reading Serg's input, we can get a kiln to work pretty well. Might need some assistance tweaking it, if you stay in touch on the forum. Thanks for all your information.

Nothing to stop you from penciling in a spot for next winter, though . ;) ;D ;D

Den Socling · January 23, 2006, 05:58:56 PM

Harold,

Are you going to use Sergey's design. That's continuous vac but it's what we call a steam vac. You leave some air in the chamber and the placement of the heating loops and condenser set up an 'engineered convection'. (That's DanG's newly coined term from another thread. 8))

I'd be glad to help you with any design but I have a feeling that there is a lot of potential for a 'simple' design using Sergey's. What Sergey lacks is process control and I could help you there.

Den

Fla._Deadheader · January 23, 2006, 08:49:44 PM

That's exactly what we are planning to do. I think we will use a fan to circulate the air from pulling a little more than half the air out. This wood is new to me for drying, and don't wanna chance messing it up. Too valuable.

serg · January 23, 2006, 11:08:23 PM

For quality of a dry wood movement of air should be small.
I use 0.5 m / second.
The fan will give speed having warmed up woods. SPEED of MOVEMENT of the MOISTURE FROM MIDDLE of the WOOD WILL NOT GIVE the FAN. It(he) necessarily will give dead zones and fast evaporation of a moisture from a surface of a board! There is no pair - there are cracks.
The temperature, vacuum, having warmed up - a pause, the top layer cools down increases a gradient of movement of a moisture from middle of a wood. Pairs constant - gives excellent(different) quality, prevents face cracks, I do not paint end faces of boards, I do not use some mastic! This work does(makes) pairs.
Precious breeds should be dried only in soft the diagram with constant humidifying a stack.
Sergey.

Fla._Deadheader · January 24, 2006, 12:00:43 AM

Thanks for that info, Sergey

Den Socling · January 24, 2006, 08:28:08 AM

Sergey is right about the fan. A major problem with steam vacs is air circulation. It's hard to get air equally spread through a stack in a chamber.

It will be hard to know exactly how the process should be controlled but 1) keep the chamber pressure in a set range to eliminate that variable 2) control heating water temperature by monitoring internal wood temperature 3) control condenser temperature by monitoring humidity.

Are 'swamp coolers' used around your new neck of the woods?

Fla._Deadheader · January 24, 2006, 08:59:42 AM

:-[ :-[ What's a Swamp cooler ?? :

:

My plans are, paint the tank black and set in the sun. A lot of days are partly cloudy. Should WARM the tank, without getting REAL hot. That should help the wood to ''Sweat'', correct ??

I think dis-continuous is the way to experiment. That way, monitor the amount of water, while comparing humidity and pressure ??

I have a visual picture of how Serg uses the cool water to create the draft. We have LOTS of cool water. Just take a shower if you don't believe me. It's a REAL heart starter :

:

Den Socling · January 24, 2006, 09:39:45 AM

A swamp cooler is an evaporative cooler or cooling tower. But when I say 'cooling tower', some people visualize Three Mile Island. :D

Fla._Deadheader · January 24, 2006, 09:49:06 AM

When I lived in Arkansas, they had square metal boxes sitting on the porch, with a ''water cooler'' that was somewhat of an A/C ?? Something like that ?? I'm gonna be touring the scrap yards of San Jose Thursday. Need to know what to look for, and why ???

Den Socling · January 24, 2006, 10:44:35 AM

yep that's a swamp cooler. All they do is dump water down over a 'fill' that makes a lot of surface area and that makes some evaporation and that cools the water that's left.

You're going to tour the scrap yards of San Jose?? You're a braver man than I, Gunga Din. :D

Fla._Deadheader · January 24, 2006, 12:09:49 PM

No problema. I've lost over 30 pounds, and the guy taking me is REALLY outta shape ;) :D :D :D

Would something like that cooler be the way to mave the air and make the wood sweat. What about the black paint and sitting in the sun. Good or not ??

Den Socling · January 24, 2006, 01:53:00 PM

On the one hand, I don't like the idea of black paint because we lose control. On the other hand, it would be nice to have really cheap heat. I'm still thinking about it.

Chamber pressure would limit temperature. Humidity could be used to control drying. Something might work.

Fla._Deadheader · January 24, 2006, 02:53:20 PM

Take yer time thinking. No big rush. Haven't seen the tanks, yet. That's Thursday, hopefully.

Wanna get this right if we can, without too many changes.

bmohebby · January 30, 2006, 09:29:41 AM

Dear Sergey and all other international friends;

I am really surprised when I read your message due to talking about our government and country. You and all friends should know that Persians are very warm and friendly people and there is nobody to force us for such contacts! I can easily access to internet from my office and keep in touch with everybody, I like.

I do believe that political borders should be put away and we must think and communicate as very close friends, even we have different nationalities. This is one of the life's beauties.

You, me and all human beings have same fate, necessities, sense etc. So, there is no need to borders. Politicians can not think in a right way, I believe. All of them even can't believe themselves; so how do they believe others?! They are always looking to find something for people to amaze them. It is their job and business. I do emphasize that DO NOT BELIEVE EVERYTHING IN MEDIA!!!! POLITICIANS ARE GOOD ACTORS AND ACTORESSES! Can you believe how many people were killed in Iraq for nothing? They were 120,000. It is a quiet big town or city. Who can judge it? When we all could think in a right way, PEACE presents us the best life. When we think darkly, WAR welcomes us. Which is better?

You and other friends might be interested to know about my country. OK..

Iran is a huge country, with different climates, very similar to USA. It has a civilization for more than 7500 years! (the oldest civilization through the world). Iranians had believed different religions since then by now. They were Mithraism (believing LOVE), Zoroastrianism (believing a great LORD), and Islam (believing both of them). At the moment, majority of Persians are Moslem, Christian, Jews and Zoroastrian. All people with different religion live under a same flag very friendly. Iran has different ethnics. FARS (PARS=Persians who speak in Persian language), Turkmen (who speak in Azerbaijani, a type of Turkish language), Arabs, Kurds (the oldest ethnic in Iran who speak in Kurdish language. It is a type of Persian language) and Lors (who speak in Lory) etc.

My country has the youngest generation in the world and most of people are well educated. We would like to be as a very developed country. However, dark international challenges try to stop this country. Because, all media try to present a dark face of this country. I have been in Europe for several years and am familiar how other nations think about us. However, they change their mind when face with Persians and understand how they were pretended via media.

You and everybody is very welcomed to this country to find the reality.

With the best regards

bmohebby · January 30, 2006, 09:40:23 AM

Dear DanG;
Hello
Thank you very much for your attention. It is able to work continuously and dis-continuously.

Regards
Behbood

serg · January 30, 2006, 09:55:33 AM

bmohebby, hi!!!
I ask a pardon you for that that you have thought about bad!
I love IRAN, and as to political structure and applications of your PRESIDENT about deleting from the person of the ground of Israel to YOU to decide.
We discuss not a policy(politics) of Iran, WE discuss Vacuum technology of IRAN which was developed by YOU, she(it) is interesting to me. You long were silent on a forum so I have decided that at you censorship. If I am not right, once again I am sorry!
Now to vacuum technology.
You dry or change color wood? At you the mode of drying consists from 150 С? Or you apply 70 С?
Sergey

DanG · January 30, 2006, 10:24:01 AM

Welcome to The ForestryForum, Dr. Mohebby!

We are excited to have you join us here, and are very interested to learn more about your kiln. I have many questions about it, but will try to ask only a few at a time.

What chamber pressure are you using, and do you vary the pressure under any circumstances? At what temperature do you operate it? What types of wood do you dry and how long does it take?

These are very basic questions, so any other details you could share with us will be greatly appreciated.

Thank you
DanG

Den Socling · January 30, 2006, 05:43:38 PM

Dr. Mohebby,

Welcome to the Forestry Forum. We are very pleased that you can join us.

I was very busy today and didn't have time for email or forums but I quickly wrote the note about language barriers after I got email from Sergey. He was concerned that his translation offended you - or so I think that was what he was saying. It's very difficult to understand his translations, sometimes.

So welcome, political barriers are not going to be in our way and we will work around the language problems. In another thread, we are talking about building a low tech vacuum kiln for Costa Rica. My idea is to create a rotation of air around a chamber by heating one side with the sun and condensing water vapor on the unheated side. Hopefully, you and Sergey will help.

And Sergey, when you don't know a word and can't find a translation, :P You can always plug in one of these silly faces as punctuation. :D

Den

serg · January 30, 2006, 11:21:59 PM

Dr. Mohebby, Den correctly speaks. I completely believe his(its) words. Together we shall create a vacuum kiln in CR!
Sergey.

ronwood · January 31, 2006, 01:35:38 AM

Welcome to The ForestryForum, Dr. Mohebby! Hope to hear more about your kiln.

Ron

fstedy · January 31, 2006, 03:18:24 PM

WELCOME
smiley_biggrin01
DR. MOHEBBY

I have been following this thread in the background and am very interested in building a Vac Kiln. I have been getting a lot of calls for thick fireplace mantels and I know they are difficult to dry.

Norm · January 31, 2006, 03:34:56 PM

Welcome to the Forestry Forum Dr. Mohebby, nice to have someone to talk with from your part of the world.

Kirk_Allen · January 31, 2006, 08:29:55 PM

Welcome to the Forestry Forum Dr. Mohebby. Looking forward to hearing more about your country.

oldsaw · February 03, 2006, 03:49:11 PM

So, Dr. Mohebby, do you have a good recipie for Ghamay (spelling?)

Persian food is wonderful. Have a great local place, the owner is from Isfahan, a very beautiful city. Yes, the people are very friendly.

Welcome aboard. These guys may want to know about your kiln, but I'd like to hear something about the trees in Iran. What kinds of trees grow there?

Mark

serg · February 04, 2006, 09:14:27 AM

Dr. Mohebby,Hi! I have an opportunity to learn young people to joiner's(wood) business. After study they work in large firms of Moscow. It is author's, exclusive work of Moscow company "Game".
Dr. Mohebby, what profession are your students have? ???
Sergey.