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General Forestry => Drying and Processing => Topic started by: starmac on November 18, 2017, 12:27:30 PM

Title: reefers for kilns
Post by: starmac on November 18, 2017, 12:27:30 PM
I see a lot of guys using or asking about using old refer trailers, truck bodys or containers for kilns.
Reefer trailers are routinely replaced because the insulation retains moisture and are replaced when it gets to a certain level, many times the unit is saved and just installed on a new trailer. One reason is that as the insulation becomes saturated the trailer gains weight, but I understand it also affects it's efficiency.

Would this affect the efficiency of a kiln, or would the heat eventually dry it back out? Has anybody ever noticed a problem, as far as the insulation not working as well as you thought it should?
Title: Re: reefers for kilns
Post by: Peter Drouin on November 19, 2017, 05:33:29 PM
Good point, I had a call for a  40' one for $ 600.00. I have too much going on right now.
Title: Re: reefers for kilns
Post by: mike_belben on November 19, 2017, 07:53:52 PM
Thats very cheap for anything 40' that isnt trash.  Especially insulated.  At that price id expect a banged up mold sponge with a busted door.
Title: Re: reefers for kilns
Post by: Gearbox on November 19, 2017, 09:34:10 PM
I was thinking that they were insulated with foam . Its been a while since I have seen one wrecked .
Title: Re: reefers for kilns
Post by: YellowHammer on November 19, 2017, 10:09:24 PM
If the insulation is taking on water, has broken down, and is generally unserviceable for refrigeration work, it will also be a poor choice for a DH kiln. 
Title: Re: reefers for kilns
Post by: GeneWengert-WoodDoc on November 20, 2017, 11:40:41 AM
Appreciate that heat will indeed help dry out wet insulation, but the environment in a kiln is often quite humid.  However, even if the kiln has a warm and moderately humid interior, as the humidiy (vapor) moves into the wall, which is cooler, then the humidity will increase and often will reach a condensation level.  So, it is critical that the walls, floor and roof all be sealed very well to prevent this migration.  Plastic sheets will do that for walls and roof, with the plastic or other sealer put on the inside so the moisture vapor cannot reach the insulation. 

As you mention, wet insulation weighs more and this weight can dislodge the insulation over time, so that "sagging insulation" sections will have poor insulation qualities.  Also, wet insulation does not insulated well, even if it does not sag.  Poor insulation means higher drying costs...more energy and longer times.

When using a DH kiln, the price of heat to get the kiln hot enough to start and then to keep running suggests that we need about 8" of insulation...insulation that works correctly.  Adding insulation to a reefer might be a good idea, but again, avoid moisture.  So, adding it to the exterior is likely the best idea.  I also suggest painting the roof black on the outside to gain a small amount of solar heat.
Title: Re: reefers for kilns
Post by: starmac on November 21, 2017, 08:13:27 PM
It seems like an old reefer would be a poor choice if 8 inches is needed to be efficient, I doubt they have over 2. If you have to add 6 more, might as well start from scratch and build it to your specs.
Title: Re: reefers for kilns
Post by: GeneWengert-WoodDoc on November 21, 2017, 11:24:48 PM
I would suggest you consider the cost of building your own kiln that will likely have better insulation; compare this cost to upgrading a used reefer.. A new kiln also will likely last longer than a converted reefer.  Both will work, so figure out the best economic approach...it is mainly an economic decision.

One additional thought is that if we have aluminum and are drying fresh oak, the acidity can quickly eat aluminum.  Small problem with air dried oak.
Title: Re: reefers for kilns
Post by: mike_belben on November 22, 2017, 07:51:15 AM
I think id prefer a conex container.  Atleast theyre easy to pick up and move if you decide to relocate or sell it.  And you can weld structure right to them.  Cutting into and framing stuff in a reefer is a pain. 
Title: Re: reefers for kilns
Post by: YellowHammer on November 22, 2017, 08:33:26 AM
A well built kiln is a quite an undertaking, and it's important to make sure everything is right.  It just starts with the container or building.  I bought my high cube reefer while it was still in service, made sure it was in good shape, traded the refridgeration equipment for new seals, and love it.  It even had a few bonus packs of beef jerky still in it from the last load it hauled. It has a sealed, stainless steel interior, will not corrode and is still bright and shiny.   

I also have a stick built kiln and it has its advantageous, also.  Both kilns are in 24/7 service from the day they were installed, many years ago. 

Standard metal Connex containers are made from Cor-ten or similar, a "weathering" steel, designed to passivate in a corrosive environment.  So it has a limited design life and typical Connex shipping containers are taken out of after only 5 years of ocean transport service.  That's one reason there are so many used for sale.  After several years of use, my stainless high cube looks and works as good as the day it was put in service.   Kiln drying green wood produces significant corrosive vapors and the Nyle kiln guys have told me stories of standard Connex containers rusting out and pin holing in a just a few years of kiln service.   

I guess my point is that considering the effort taken to build and operate a proper kiln, the value of each load of wood processed in Nyke 200 or equivalent kiln, (4,000 bdft per load, average $4 per bdft retail sails, $16,000 per load, one load every 7 to 9 days), and the cost of electricity to operate a DH kiln (compressor plus 4 KW heat strips, on for days or longer if not properly insulated), then it can become painfully expensive to start out with some sort of container or building that isn't in top shape and try to save money up front.
Title: Re: reefers for kilns
Post by: starmac on November 22, 2017, 02:48:03 PM
40 ft containers here always bring anywhere from 3 to 4 thousand bucks at any auction, 20 footers are no cheaper, so would not be something I would want to start with.
I have a neighbor bought 4 brand new ones to the tune of 6500 bucks a piece. His intentions were to build a house out of them, which has since changed. Myself, I thought that was some pretty expensive walls.
Title: Re: reefers for kilns
Post by: mike_belben on November 22, 2017, 08:31:11 PM
Good lord.
Standard 40s are $1700 each in atlanta.
Title: Re: reefers for kilns
Post by: starmac on November 22, 2017, 09:02:33 PM
I know, but we get to pay that Alaska premium for things like them. lol
Title: Re: reefers for kilns
Post by: tule peak timber on November 22, 2017, 09:39:21 PM
I built a kiln by the Nyle book and it cost a fortune. Never used it once and sold the property with the kiln on it. When I moved to my present location I bought a refer container for 7000$ and put a Woodschmooser 4000 unit in it that has run more or less 24/7 for 11 years. I'm toying with the idea of another kiln with a wood fired boiler and the payback numbers are good, but other things keep popping up.The cost of containers where I'm at in SoCal is very high also and I just got a bid to move two of them to AK at a tidy 30 k give or take filled with equipment. Sadly Ak is out for me ! Rob
Title: Re: reefers for kilns
Post by: starmac on November 22, 2017, 10:07:01 PM
That bid may or may not be a good deal, where in Ak.  If it was on the road system anywhere south of Fairbanks, I would move them for you, but sadly California is out for me. lol
Title: Re: reefers for kilns
Post by: Geeg on November 22, 2017, 11:43:10 PM
I just finished my 20' reefer kiln and got one load in this year. I am happy with the way it operates and was not to hard to put together. I dried 2000bf of red pine that had been outside for a year. It took 3 days to finish the load down to 8%. Here is the link to my build. I just hope the paint that I used to seal the container works as advertised.

https://forestryforum.com/board/index.php/topic,86277.0.html
Title: Re: reefers for kilns
Post by: Cazzhrdwd on November 23, 2017, 06:33:11 PM
I've had my reefer container for at least a decade. It takes the same electric, the same time to heat up. It's the most consistent kiln I've ever had. If the walls were saturated with water, I doubt it would hold heat very well at all. It's also lined with stainless steel, so it's very easy to keep it sealed.
Title: Re: reefers for kilns
Post by: WLC on November 23, 2017, 06:54:34 PM
Quote from: starmac on November 22, 2017, 02:48:03 PM
40 ft containers here always bring anywhere from 3 to 4 thousand bucks at any auction, 20 footers are no cheaper, so would not be something I would want to start with.
I have a neighbor bought 4 brand new ones to the tune of 6500 bucks a piece. His intentions were to build a house out of them, which has since changed. Myself, I thought that was some pretty expensive walls.

That's what gets me.  They have them at the port in Anchorage all the time, but we still pay the Alaska premium for them.  They are a bit cheaper down here than in FBX though, but not by much.  I had a friend in Delta that told me not long after we moved up here that I would find that in AK they charge freight on a haircut.  That's not too far off the truth.
Title: Re: reefers for kilns
Post by: starmac on November 23, 2017, 09:41:02 PM
Supply and demand, supply and demand. Anchorage gets them, but not near, as in not even 1 % of what major ports do down south, and they are quick handy shelters to keep stuff out from under blue tarps here, so bring a premium.
Title: Re: reefers for kilns
Post by: mike_belben on November 24, 2017, 09:04:12 AM
Yeah im sure theres hardly a person in alaska who doesnt want one.  Hawaii was similar with everything having a huge markup.  It cost about $1200 at the time to matson a vehicle from LA but the dealer markup was $10k vs the mainland.

Conversely, NYC has great prices on old construction equipment.  Other than the handful of contractors in the area who must run pretty looking machines to remain credible among the bankers theyre working for, who wants a beat up old dozer in brooklyn?  And who outside of NYC wants to deal with going there to see one and worse, arranging to truck it out. 

No demand = cheap
Title: Re: reefers for kilns
Post by: tule peak timber on November 24, 2017, 09:15:11 AM
This summer In Las Vegas I happened to strike up a conversation with a guy that buys and sells used containers. The bar tender later mentioned he was a regular and worth millions. He lives in a high rise on the strip. Is there a substantial markup on containers, it would appear so.  Rob
Title: Re: reefers for kilns
Post by: mike_belben on November 24, 2017, 09:43:14 AM
When the railroad or freight carrier is switching the fleet from say 40 to 40hc, or 40 to 48, 48 to 53 ..  You know.. The constant push toward bigger better faster..  Theyll want to unload tremendous volumes of containers all at once to clear the yards for delivery of new containers.  Someone with deep enough pockets to buy them all and actually move them off site is gonna get quite the deal.  If you can afford to wait for the money back at market price, then yes profit margin will be substantial. 

At port in NJ a 40' will bring maybe $1800.  Few hours north in springfield i was selling them for $2500-4000 based on condition, delivered to end user.  If youre hiring out the transport then there is no savings but if you are the transporter, and youre buying bulk diesel and the truck is paid, then you get to pocket the markup.
Title: Re: reefers for kilns
Post by: jaciausa on November 26, 2017, 05:21:41 AM

I have been planning a kiln in my Great Dane reefer trailers for some time. I was not aware of the problem oak and aluminum have. How big of problem if the oak or other wood is air dried?
I was going to re insulate over the frp sidewalls and ceiling inside.
Title: Re: reefers for kilns
Post by: YellowHammer on November 26, 2017, 08:44:13 AM
Air dried is better.  However, the inside of my reefer is stainless steel.  Is yours aluminum clad on the inside?
Title: Re: reefers for kilns
Post by: mike_belben on November 26, 2017, 12:10:51 PM
Wouldnt insulation and vapor barrier pretty well cure the corrosivity issue?
Title: Re: reefers for kilns
Post by: starmac on November 26, 2017, 01:53:45 PM
I may be wrong, but I thought all refers had an aluminum floor, no matter what the walls were lined with.
Title: Re: reefers for kilns
Post by: jaciausa on November 26, 2017, 02:13:08 PM
I always thought my units were stainless on the floor, I need to go check the serial number and find the specs. Also take a magnet. I am in the process of finding another reefer trailer and I have found one with 3 side doors that is aluminum. I believe in any case I can retrofit and come out well ahead. I plan on spraying the foam and covering or using r board. I would already be started but received loads of dry lumber this summer that I need storage for. Any advise on the insulation or other is appreciated. Thanks
Title: Re: reefers for kilns
Post by: jaciausa on November 26, 2017, 05:08:55 PM
I am now sure that the floor and the outside must be aluminum. They did a fantastic job polishing the outside when this was built. It will just be another obstacle to contend with. Would ERC be any more corrosive then white oak, and are there any more woods that would cause problems?
Insulating the floor from the top and using a taller inverted track could work, but that gets me  to thinking that building from scratch would be the best option! Any steel placed inside also would corrode from the moisture.
Title: Re: reefers for kilns
Post by: mike_belben on November 26, 2017, 08:08:43 PM
Paint it.  Works on bridges and battleships.

Btw stainless is nonmagnetic other than 400 series.


Title: Re: reefers for kilns
Post by: YellowHammer on November 26, 2017, 08:34:08 PM
Steel will rust pretty bad in a kiln, galvanized steel even worse, but I don't think aluminum is in any real threat from corrosion failure in a kiln. 

I have two Nyle kilns, and both of the chassis of the units appear to be constructed of aluminum sheet metal maybe 1/8" thick.  Nyle wouldn't use it if it was a significant problem.

Also, I know the floor runners I can see are extruded alumimun and is one of the reasons I bought the reefer.  This structure makes the floor dead flat, and I look at it every time I load and unload the kiln, and I have seen no degradation at all.  It looks as good as the day I put it into service, more than two years ago.  In that time, I have had it running 24/7 and pump a load out every 7 to 9 days.

I would not hesitate to build more of these, they are maintenance free, and work extremely well.  Due to the total lack of chamber degrade and zero maintenance I prefer it over my stick built. 

Reply #26 has some pics of the floor
https://forestryforum.com/board/index.php/topic,82071.100.html

BTW, eastern red cedar is a lot tougher on the kiln machine than the chamber.  When dried, it vaporizes some of its oils and it condenses in the drip pan as a white crystal mashed potato looking material, and clogs up the drip tube and sometimes the drip pan. 
Title: Re: reefers for kilns
Post by: jaciausa on November 27, 2017, 08:01:37 AM
I am glad I have the experienced help from all of you. My floor is not a duct aluminum floor, more of a continuous probably alum sheet metal.Metal only goes up about 18 inches on sides. The plastic coating most likely is glued on plywood- frp as it is fastened only on top/bottom. I am now going to use this the way it came, no insulation added except under floor. Outside probably is 300 grade stainless like one of you mentioned.
The food service industries use these type of trailers and many are available when they update there fleets. The units I bought were taken out of service because diesel emission rules outlawed there use in some states. Being a portable kiln could be a plus in some cases. It also means there are most likely some in every state ready to become kilns. Tell them its for cheap storage or they will up the price! 
Title: Re: reefers for kilns
Post by: Cazzhrdwd on November 29, 2017, 10:55:01 PM
Quote from: YellowHammer on November 26, 2017, 08:34:08 PM
Steel will rust pretty bad in a kiln, galvanized steel even worse, but I don't think aluminum is in any real threat from corrosion failure in a kiln. 

I have two Nyle kilns, and both of the chassis of the units appear to be constructed of aluminum sheet metal maybe 1/8" thick.  Nyle wouldn't use it if it was a significant problem.

Also, I know the floor runners I can see are extruded alumimun and is one of the reasons I bought the reefer.  This structure makes the floor dead flat, and I look at it every time I load and unload the kiln, and I have seen no degradation at all.  It looks as good as the day I put it into service, more than two years ago.  In that time, I have had it running 24/7 and pump a load out every 7 to 9 days.

I would not hesitate to build more of these, they are maintenance free, and work extremely well.  Due to the total lack of chamber degrade and zero maintenance I prefer it over my stick built. 

Reply #26 has some pics of the floor
https://forestryforum.com/board/index.php/topic,82071.100.html

BTW, eastern red cedar is a lot tougher on the kiln machine than the chamber.  When dried, it vaporizes some of its oils and it condenses in the drip pan as a white crystal mashed potato looking material, and clogs up the drip tube and sometimes the drip pan.

Same with mine, never had a problem with the aluminum floor.
Title: Re: reefers for kilns
Post by: mike_belben on October 13, 2020, 08:11:30 AM
I had a thought recently..  Maybe a bad one.  kiln wizards please chime in on this.  


How could one make use of the actual over the road diesel refrigeration unit to dry wood?  Lets imagine a guy with a working reefer box and no money or real serious need for a kiln, pertaining to firewood lets say, cant go all that wrong.. Not some lumber business with a credit line and high dollar flooring and a defined ROI. And definitely not a plan to spend $15k to make back $1500!  I have enough of those!  ;D



I think placing lumber into a walk in freezer or cooler would not work well or people would do it. Im guessing it would just condensate the entire interior and also the water molecules in the wood arent going to be very excited about leaving their cozy fiber home at low temps. 


What if a sizeable tin ductwork loop was suspended from the ceiling and connected between supply and return baffles of the unit, forcing cold air through the duct, with a plastic or tin drip catch pan style gravity drain system to handle moisture removal? I made many of these pans and panchos at smith and wesson for oil leaks in the basement ceiling that came through from the machining floor above so i know those are simple and effective at putting liquid in a bucket somewhere.

 

For circulation and heat i was thinking a variable displacement, belt drive hydraulic pump could go on the crank pulley and a closed loop hydraulic circuit be used to spin fans inside the chamber.  These parts are easy to come by from ride on or truck based sweepers.  Tennant, elgin, et al.  Plumbed in series with a variable pump, airflow will be controllable.  Individual fans could be turned on and off and all could run faster or slower.  


 The hydraulic cooler and engine radiator would go inside the chamber for cogeneration of heat for thr interior space, while the refrigerant condensor obviously stays outside.  Maybe a wastewood fired stove or boiler for initial startup/supplemental heat? 



Please leave the corrosion and insulation concerns aside, just wanting to discuss the merrit of these components.  One could use a refer unit on any custom enclosure if it could work. 

Title: Re: reefers for kilns
Post by: mike_belben on October 14, 2020, 10:38:51 AM
anyone?  @YellowHammer (https://forestryforum.com/board/index.php?action=profile;u=11488)  @tule peak timber (https://forestryforum.com/board/index.php?action=profile;u=25190)  @wooddoc (https://forestryforum.com/board/index.php?action=profile;u=25580) 
Title: Re: reefers for kilns
Post by: tule peak timber on October 14, 2020, 11:57:11 AM
Just my 2 cents. I do have experience with custom electric and hydraulic driven systems for refrigeration in my past boats and they both work fine.
  Usually trying to reinvent the "wheel" so to speak when Nyle has it down to a science is going to cost more in the short-and long run. In addition when the inevitable problems arise there is history and knowledge available to solve issues from the known system technology.
 I do not mean to discourage you from "thinking outside of the box"Just my opinion. Cheers  Rob
Title: Re: reefers for kilns
Post by: mike_belben on October 14, 2020, 10:09:07 PM
I live in a camper because im that poor.   Im talking about making something from nothing like i always have.  Its not discouraging, just not any sort of option. 
Title: Re: reefers for kilns
Post by: Southside on October 14, 2020, 10:58:08 PM
Trying to visualize what you are thinking here.  Start the air loop at the top, it will be dry, hot air correct?  You say firewood, how will the air get down through the stack? After it passes through the stack how do you get the air over the condenser to get the moisture out? 

One thing I see that presents a problem is that you are always burning diesel to generate the necessary heat, and I have to think that reefer engine will cost more per hour to run than an A/C compressor.  In a closed loop Nyle kiln once the air is over 80F the waste heat from the compressor keeps the temps up, actually it can keep it too high and you need to dump air to stay in the right spot.  The compressor kicks on and off depending on the setting, so the electrical draw is pretty low.  

Airflow is what gets the moisture out of the wood, if you are just heating the whole stack and not getting velocity across the face of the wood then moisture removal will be slow.  
Title: Re: reefers for kilns
Post by: YellowHammer on October 15, 2020, 12:23:18 AM
For a workable kiln, all you need a little heat to warm up the wood, ambient temperature air coming into the kiln, a means for the wetter and warmer air to leave the kiln (vents), and a way to maintain the slightly warmer temperature continuously.  Air flow can be very minimal as the wood dries.

A truck reefer makes an excellent unsulated box.  Then a very small vent would be added at each end of the the reefer to allow the introduction of cooler, dryer outside air, and the expulsion of warmer moist air.

The vents would be small, because some sort of heat source would be required for the incoming air and you'd have to establish a heat balance where you could heat the incoming air at the rate you were expelling the warm moist air.  

Adding heat takes energy, and generally the simplest from a sawmill standpoint is from burning wood sawdust or waste.  The idea would be to generate just enough heat to warm the incoming air, but no more.

The heat would have to be supplied by a source, such as a radiator, heat exchanger, direct fire burner, diesel exhaust, etc.  The reefer ac units would have coils and such that could be salvaged.

If you simply expel the moist warm air, you don't need a chilled coil to remove the water from the air.  You just need to add ambient air.  Out with the wet and warm, in with the ambient and dry.

This would be a very simplistic system, and it would dry wood, not optimally, but it would work.  

I don't know if this helps you or not.  





Title: Re: reefers for kilns
Post by: farmfromkansas on October 15, 2020, 03:43:40 AM
I have a 48' reefer trailer, the seller removed the refer unit, and the wheels, and delivered it setting on the ground to my location, where we set it on some 4x8 prestressed concrete panels, one on each end.  The back 4' ceiling insulation was shook loose, and I cut into it, the insulation seems to be the same stuff they make Tuff-R insulation from.  Planned to replace the piece in the rear, using some foam adhesive and new Tuff-R braced up with some 2x4's, but haven't gotten around to it.  The thing works great as a solar wood dryer, I have a ready supply of dry wood now.  Downside is, I can't get it hot enough to sterilize, so any new wood will have to be coated with solubor. The trailer has fiberglass panels on the inside.  Heat limit 160
Title: Re: reefers for kilns
Post by: scsmith42 on October 15, 2020, 06:55:49 AM
Mike, I think that your energy costs would be significantly more trying to reutilize a diesel powered reefer unit for a DH kiln, versus a Nyle unit.

One thing to consider is if you can decouple the engine from the actual reefer unit, and use shore power for it.  You could take the components and duct them so that incoming air crosses over the A coil with the drain pan under it, and then exits passing the condenser coil to heat it.

My experience with hydraulic systems is that they are not as efficient as electric, nor can you create your own electricity with a diesel generator as inexpensively as you can buy it.

Just some thoughts to consider.

Scott
Title: Re: reefers for kilns
Post by: mike_belben on October 15, 2020, 09:22:07 AM
I have 2000 gallons of vegetable oil in totes right now.  I convert mechanical diesels to straight veggie easily.. They cost me ZERO to run. They cost me very little to overhaul.   I am a fruitloop, normal person costs are not my costs so please lets just not talk money guys. I just want to discuss the physics of it, not the finances. 


@Southside (https://forestryforum.com/board/index.php?action=profile;u=24297)  think of a basement with central AC ductwork hanging from the joists as usual.  Brand new install on a hot, humid summer day.  Flip the AC on and moisture condenses and drips off the ductwork.  

Now switch out the basement for a container full of wood.  Catchpans to collect and evacuate the condensate.  

My concept was not to cool the entire container, only the ductwork interior to make a chiller coil that removes moisture.  This would be very low load for a 3cyl reefer because its such a small air volume compared to what theyre designed for and it may even cause wet stacking.  I figured throw in the hydraulic fan cooling purposefully for the 20-30% efficiency losses that would create sufficient load for the engine to run well and waste heat that would be generated to warm the box while forcing the airflow through the wood using curtain baffles or whatever proves to be needed. Trial and error is the fun of it all IMO.   [Whats the fun in mortgaging my freedom to buy a perfectly functioning boring old nyle with zero bugs for me to enjoy working out, and have to actually work for money to pay it off ..honestly. ] 



@YellowHammer (https://forestryforum.com/board/index.php?action=profile;u=11488)  

Yes very helpful, thank you sir.  While back I did build a small wood fired kiln that was very, very successful at drying firewood but also very likely to burn down so out came the burner tubes and its just a drying shed now with open vents top and bottom all the time.  Ive recently concluded that it dries lumber quite well over a summertime with no effort so that definitely supports your simple suggested layout.  Much simpler in practice than reading kiln build threads makes it sound.  


If a chilled condensate loop isnt going to rapidly speed the drying process i wouldnt waste my time.  I have need of a drive in, skid steer loaded firewood drying rig in the next year or two.  I also need to house an onan 4cyl diesel generator that will power the shop without excess noise killing the neighbors.  I will simply plan on putting the generator inside the can, properly baffled, and letting the radiator and exhaust cogen the heat and fan push the air.  I have a huge industrial heat exchanger made from probably 100feet of exhaust piping bent into a big sponge of tube that goes inside a big plenum.  I will run the exhaust through that before exiting the can and the airflow into the wood chamber will have to pass over the pipe exchanger.  


So thatll be that.  Powerplant inside a kiln.. 2 birds with one stone.


Thanks guys. 

Title: Re: reefers for kilns
Post by: tule peak timber on October 15, 2020, 11:12:17 AM
Quote from: mike_belben on October 14, 2020, 10:09:07 PM
I live in a camper because im that poor.   Im talking about making something from nothing like i always have.  Its not discouraging, just not any sort of option.
Mike,For what it is worth,when I first met my wife we lived in a borrowed travel trailer parked at the edge of an oil field supply company's lot for years.We used buckets and a hose hung out of a tree for plumbing.
   It is possible to make something out of nothing.
   Your friend on the Forum.......
Title: Re: reefers for kilns
Post by: alan gage on October 15, 2020, 11:51:38 AM
What about building a solar collector next to the reefer (empty box with clear panels and painted black inside) and then a fan to blow that air into the reefer?

Alan
Title: Re: reefers for kilns
Post by: doc henderson on October 15, 2020, 12:09:37 PM
@GeneWengert-WoodDoc (https://forestryforum.com/board/index.php?action=profile;u=20498) 
Title: Re: reefers for kilns
Post by: mike_belben on October 15, 2020, 02:50:10 PM
Quote from: tule peak timber on October 15, 2020, 11:12:17 AM
Quote from: mike_belben on October 14, 2020, 10:09:07 PM
I live in a camper because im that poor.   Im talking about making something from nothing like i always have.  Its not discouraging, just not any sort of option.
Mike,For what it is worth,when I first met my wife we lived in a borrowed travel trailer parked at the edge of an oil field supply company's lot for years.We used buckets and a hose hung out of a tree for plumbing.
  It is possible to make something out of nothing.
  Your friend on the Forum.......
Good on ya Tule.  I have no complaints.  I could sign my name on a brand new house and re-enter the high pay higher payment rat race but its not worth it to me, BTDT, recipe for misery.
  My kids are still in the trash everything phase, but im the one who has to pay for or fix what they wreck.   let them trash an old camper. When they get mature enough to treat things nice or get out, we will have nicer things.  None of that makes me tick so it can wait.  I got no payments, deed is in the safe and i can tell everyone to pith off.  Thats what i care about. We may not have much but its OURS.  The Lord has been good.  
Title: Re: reefers for kilns
Post by: mike_belben on October 15, 2020, 02:53:12 PM
Quote from: alan gage on October 15, 2020, 11:51:38 AM
What about building a solar collector next to the reefer (empty box with clear panels and painted black inside) and then a fan to blow that air into the reefer?

Alan
Firewood selling season is short here and when its over thats it for the year. People just dont buy wood in summer where winters are milder.  
  I can make a generator come to life on a rainy night but the sun just doesnt listen to me. 
Title: Re: reefers for kilns
Post by: alan gage on October 15, 2020, 03:46:44 PM
Quote from: mike_belben on October 15, 2020, 02:53:12 PM
Quote from: alan gage on October 15, 2020, 11:51:38 AM
What about building a solar collector next to the reefer (empty box with clear panels and painted black inside) and then a fan to blow that air into the reefer?

Alan
Firewood selling season is short here and when its over thats it for the year. People just dont buy wood in summer where winters are milder.  
 I can make a generator come to life on a rainy night but the sun just doesnt listen to me.
Yeah, I hear ya. I know it wouldn't fly up here in the winter, didn't know what it was like in your neck of the woods. I guess mostly I was thinking of something that would let you cheaply dry wood through the summer and then have it ready to sell in the winter.
Alan
Title: Re: reefers for kilns
Post by: Walnut Beast on October 15, 2020, 10:30:57 PM
Quote from: mike_belben on October 15, 2020, 02:50:10 PM
Quote from: tule peak timber on October 15, 2020, 11:12:17 AM
Quote from: mike_belben on October 14, 2020, 10:09:07 PM
I live in a camper because im that poor.   Im talking about making something from nothing like i always have.  Its not discouraging, just not any sort of option.
Mike,For what it is worth,when I first met my wife we lived in a borrowed travel trailer parked at the edge of an oil field supply company's lot for years.We used buckets and a hose hung out of a tree for plumbing.
  It is possible to make something out of nothing.
  Your friend on the Forum.......
Good on ya Tule.  I have no complaints.  I could sign my name on a brand new house and re-enter the high pay higher payment rat race but its not worth it to me, BTDT, recipe for misery.
 My kids are still in the trash everything phase, but im the one who has to pay for or fix what they wreck.   let them trash an old camper. When they get mature enough to treat things nice or get out, we will have nicer things.  None of that makes me tick so it can wait.  I got no payments, deed is in the safe and i can tell everyone to pith off.  Thats what i care about. We may not have much but its OURS.  The Lord has been good.  
Absolutely. You can make more decisions for yourself instead of them being made for you 😊
Title: Re: reefers for kilns
Post by: Southside on October 15, 2020, 10:51:18 PM
Quote from: mike_belben on October 14, 2020, 10:09:07 PMI live in a camper because im that poor


Mike - you are not the only one.  Houses don't make you money every month, they are a luxury. My approach was make the land and business buy me a house rather than the other way around.  
Title: Re: reefers for kilns
Post by: YellowHammer on October 16, 2020, 07:08:47 AM
A heated and vented kiln, whatever the manner of heating, is an excellent way to get rid of moist air in a kiln, very fast.  

A true direct fire or even indirect fire kiln will dry wet very fast as long as the heat source can keep up with the venting rate.  In many cases, burners use propane and blast heat in to warm heat the chamber.  Venturies are used to control the air flows exiting the kiln, and the more heat in and the hotter the kiln can be maintained by venting air, the more the wood will evolve moisture, and the faster that moisture will be carried outside.    

So using the heat form the engine and the exhaust will provide a good bit of heat, and since one of the byproducts of combustion is water, I would do as you suggest and run the exhaust through a heat exchanger and not introduce it unto the kiln.  I also wouldn't pump the exhaust into the chamber simply for CO safety reasons.

To maintain temperature, a simple self opening temperature controlled vent would work, and make the system pretty hands off.

If you run the generator continuously and can maintain higher temperatures, 120F or even up to 170, while still venting the moist air, you would have a very effective kiln.  You could also scavenge a few watts of power to run some fans to circulate the air in the kiln.
Title: Re: reefers for kilns
Post by: doc henderson on October 16, 2020, 07:21:20 AM
I would second the caution on the exhaust running through pipe in the kiln.  over the years, if you get a pin hole, it may not be obvious.  would hate for you or your kids to be overcome working in the kiln.  you could do a double exchange, like use the exhaust heat to warm water, then run the water through the inside heat exchanger.  CO could go into water in limited amounts, but not get into the air.  any leaks should be more obvious.  I bought some copper tube to wrap the exhaust of my log splitter.  the plan was to make it quieter, and be able to heat water in the field for coffee and or hot chocolate.  kids grow up, the the splitter only goes out once a year to Camp Alaska.  It was meant to be a novelty, fun for dads and boys in scouts.  99% of my log splitting is done within 100 feet of a full kitchen.  and yes, I do not go hungry much either. musteat_1
Title: Re: reefers for kilns
Post by: doc henderson on October 16, 2020, 07:22:37 AM
I guess you could remote mount the radiator for the generator in the kiln with a fan.  assuming it is a water cooled engine.
Title: Re: reefers for kilns
Post by: Southside on October 16, 2020, 09:30:34 AM
As a side benefit. If you do run the exhaust through a heat exchanger the condensate that drips out will be rich in N and can make for a good soil amendment. 
Title: Re: reefers for kilns
Post by: mike_belben on October 16, 2020, 11:46:57 AM
LoL.  


I would think that with a good solid load and a fairly hot interior temp that the exhaust moisture would remain in a gasseous state and go out to the night sky.  I have a 10hp 3phase lathe that will consume the entirety of the genny output on a heavy cut so that should hopefully keep the ducting de-puddled.  Sold the 10hp compressor when i didnt have deckspace to haul it but can surely find another.  



I have two big insulated water storage tanks from a rich guys discarded solar hydronic heating system, 4 or 5 parabolic trough concentrators, pumps, controllers, a wood furnace with boiler loop, lots of various industrial heat exchangers and the ability to make more... A hopper/auger fed sawdust and veggie rocket stove i built with a water heating coil .. Just so many options really to make stuff hot from trash.  Time and the waterproof, drive-in enclosure is the biggest hurdle and i can get that for a grand or so, just have to clear and grade out a good spot for it.  


But theres 300 projects ahead of all this as always.  Otoh.. The more time you have the more free junk that fits the project will land in your yard before you commence.  Just how i have always done it. 
Title: Re: reefers for kilns
Post by: Southside on October 16, 2020, 03:11:51 PM
Pre emissions junk there were a number of guys running coolers in their tractors with a drip system to apply the N to the soil. 

I think Farm Show had a couple of articles on it. 
Title: Re: reefers for kilns
Post by: mike_belben on October 16, 2020, 04:50:46 PM
Seems like peein in the ocean but i guess a drop is a drop. 
Title: Re: reefers for kilns
Post by: Southside on October 16, 2020, 06:21:11 PM
I am shocked Mike. I mean you compost Poke Weed. I figured you for the guy who manages to harvest the squeal when putting a hog in the freezer.   :D
Title: Re: reefers for kilns
Post by: mike_belben on October 16, 2020, 09:59:49 PM
Oh my compost game has stepped up considerably but thats another thread.  

;D
Title: Re: reefers for kilns
Post by: farmfromkansas on October 18, 2020, 09:38:14 AM
I have solar panels next to my reefer box, works great in summer.   What about putting a wood furnace next to the solar panels, and hooking the furnace to the vent holes on the reefer, disconnecting the solar panels long enough to dry some wood, using wood heat.  Could also hook up the return to the furnace. Not sure how hot I could get the container, probably need a pretty big furnace.
Title: Re: reefers for kilns
Post by: mike_belben on October 18, 2020, 12:07:27 PM
If the stove is outside the drying chamber you gotta put the heat in.  One could be tempted to blow the exhaust gasses in direct but an errant spark will eventually burn it and obviously smoke damage etc.. Terrible option.


I built a downdraft rocket stove where the burn occured in a steel pipe just about in the dirt, through the chamber and beneath the wood, venting up a stack on the other side of the chamber...  This thing.


(https://forestryforum.com/gallery/albums/userpics/43722/1122171530.jpg?easyrotate_cache=1511402902)



(https://forestryforum.com/gallery/albums/userpics/43722/1121171511-1.jpg?easyrotate_cache=1511401698)


The lower pic is deceiving here.. The stack has a booty fab intake concentric.  There is a 8" sleeve and elbow over a 7" stack.  The top pipe on the left side going into the chamber is preheated intake air.  the firebox was sucking warm wet air through the wood chamber into the fire, vertically down.  The fire was burning horizontal along the ground from right to left, then rising from that blob of dirt [which was to insulate the burn tube] before going up the flue.  I had to light it from that dirt covered tee to warm the riser and make the draft start in the correct direction.  It could be run reversed as well based on what was capped, closed or open. Watertank for a firebox.



It ran lava red and dried wood like nobodies business but needed all metal construction or would burn down.  I had sheetmetal baffles around the burn pipe but the wood frame was smoking hot.  I didnt plan any of it.. Just morphed.




I think using a vented waterjacket boiler [so there is no pressure vessel risk or license/permit issue] full of free, filtered rainwater, a taco circulator pump and old steam radiators connected by sched 40 with solar fans is the most fool proof and safe way to wood fire a kiln, with little expenditure or danger.  A scrapyard could procure most of it.