Re: Wet wood kiln


Hugh McLaughlin
 

Hello,

I disagree with the characterization of galvanized metal as toxic. Most galvanized coatings turn rapidly to zinc oxide (white in color) upon heating in air, and do not vaporize. The zinc concern is when welding galvanized steel with electrical arc, which does melt the zinc and can form metal aerosols, still mostly zinc oxide, but can be inhaled and deposits in the lungs and causes inflammation, known as Zinc Fume Fever, with flu-like symptoms and headaches.

As for drum coatings, they are going to burn off during the first few heating cycles and the fumes, especially if they form visible smoke, should not be inhaled.

There is a need to be cautious, but no justification for being paranoid. The issue of dioxin in biochars is another example of a virtually impossible contamination being assumed to be possible, and requires testing to eliminate the concern. When IBI looked into this issue, they decided to use MSW incinerators as the analog for biochar pyrolysis and found dioxin in MSW exhaust gases due to de novo formation. It is never found in biochars and would be biologically unavailable even if present in any actual biochar and any realistic extraction scanario (not toluene extraction, unless the groundwater is toluene, which also might happen.....).

- Hugh McLaughlin, PhD, PE

On Thursday, December 31, 2020, 3:24:05 PM EST, Harry Groot <hgroot.ngw@...> wrote:


Beware using galvanized metal.  The coating will vaporize at pyrolysis temperatures and is toxic.

Actually, the same can be said for most 55g drums.  Find out what the drum's previous use was and, if possible, what the drums are coated with on the outside because it'll all cook off and may poison your char, the environment, and you!

Harry Groot
Next Generation Woods and Dovetail Partners

On Thu, Dec 31, 2020 at 12:21 PM Ross Hunt <rossahunt@...> wrote:
Thankyou very much for the tips. I was thinking of a 4' diameter, but I will try to find a 3' culvert, although 2' are common.
I presume the hood can be made of thinner sheet metal. 
The fuel will be mostly prunning twigs and branchs <2", some punky logs and boards. Maybe later I will use larger forest slash.



On Wed, 30 Dec 2020, 22:15 Paul S Anderson, <psanders@...> wrote:

Ross,

 

Key issues:

1.  What is your fuel?    Sawmill edge Slabs or forest slash would be great.   Chips are too small.   Diameter / thickness of the fuel will dictate the time needed for drying (in relation to temperature in the dryer).  

 

2.  You need a “holder” for that fuel so that it can be dried.  Be creative.  Consider a metal rack.   But also consider using the fuel itself to hold the fuel  in an appropriate arrangement as the hot air goes through the “pile”.

 

3.  Heat.   You will have plenty of accessible heat from a RoCC kiln.   I am going to recommend about 3-ft diameter.   2-ft D is a 55 gal barrel and  is a bit small but a wonderful learning experience (I have made 5 or 6 of them with improvements each time).   And 4 ft diameter is quite hefty and begs for mechanical assistance (greatly adding to the cost).   Length related to your fuel, but 4 to 8 ft long, probably.

 

4.  Control  of heat:   The chimneys on the hood of a RoCC kiln bring together the hot emissions.   So you want to duct that heat to your dryer.   Using a fan or blower.    Dilution of the heat to a usable temperature will increase the volume of moving hot air which assists in the  drying.     

 

5.  If you need to move your kiln around, consider the RoCC n’ Roll version.  

 

Please keep us all informed of your progress.

 

Paul

 

Doc / Dr TLUD / Paul S. Anderson, PhD --- Website:   www.drtlud.com

         Email:  psanders@...       Skype:   paultlud

         Phone:  Office: 309-452-7072    Mobile & WhatsApp: 309-531-4434

Exec. Dir. of Juntos Energy Solutions NFP    Go to: www.JuntosNFP.org 

Inventor of RoCC kilns and author of Biochar white paper :  See  www.woodgas.energy/resources  

Author of “A Capitalist Carol” (free digital copies at www.capitalism21.org)

         with pages 88 – 94 about solving the world crisis for clean cookstoves.

 

From: main@Biochar.groups.io <main@Biochar.groups.io> On Behalf Of Ross Hunt via groups.io
Sent: Wednesday, December 30, 2020 12:51 PM
To: main@biochar.groups.io
Subject: Re: [Biochar] Wet wood kiln

 

[This message came from an external source. If suspicious, report to abuse@...]

I am on east side of Vancouver Island, British Columbia, Canada. A bit colder than nw Washington.

I read your RoCC kiln paper.

Thankyou for doing this work.

I was looking for a culvert and welder so I can make one. Maybe 4' diameter or smaller. How to dry my wood is still a problem, however getting the heat is the first step. Maybe if I get the kiln hot then adding damp wood bit by bit and agitating, it might work ?

 

 

On Tue, 29 Dec 2020, 21:40 Paul S Anderson, <psanders@...> wrote:

Ross,

 

Have you looked at the RoCC kilns  (covered flame cap)   www.woodgas.energy/resources   If you like it or want more info, I can assist.

 

Where are you located.   Sounds like Washington State?

 

Paul

 

Doc / Dr TLUD / Paul S. Anderson, PhD --- Website:   www.drtlud.com

         Email:  psanders@...       Skype:   paultlud

         Phone:  Office: 309-452-7072    Mobile & WhatsApp: 309-531-4434

Exec. Dir. of Juntos Energy Solutions NFP    Go to: www.JuntosNFP.org 

Inventor of RoCC kilns and author of Biochar white paper :  See  www.woodgas.energy/resources  

Author of “A Capitalist Carol” (free digital copies at www.capitalism21.org)

         with pages 88 – 94 about solving the world crisis for clean cookstoves.

 

From: main@Biochar.groups.io <main@Biochar.groups.io> On Behalf Of Ross Hunt via groups.io
Sent: Tuesday, December 29, 2020 5:21 PM
To: main@biochar.groups.io
Subject: Re: [Biochar] Wet wood kiln

 

[This message came from an external source. If suspicious, report to abuse@...]

I will be starting with  smallbackyard batches. After I get some practice and have something good to demonstrate, I may target forest companies to char thier huge slash piles.

I am low income with no funding at this time. I will build all devises myself.

Ross

 

On Tue, 29 Dec 2020, 14:03 Nando Breiter, <nando@...> wrote:

Ross,

 

What sort of capacity are you looking for? Ian and I could develop a phased batch system for you consisting of an array of batch kilns, but the investment necessary would have to make economic sense for everyone involved. The heat generated from a batch in pyrolysis would be utilized to dry the next batch in line. Contact me off-list if you would like to discuss it further.

 


CarbonZero Sagl
CP 15
6999 Astano
Switzerland

+41 76 303 4477 cell / WhatsApp
skype: ariamedia

 

 

On Tue, Dec 29, 2020 at 10:08 PM Ross Hunt <rossahunt@...> wrote:

Its too cold and cloudy here to use the sun for drying  energy. I want to use the heat from making biochar to dry the next batch. Flame cap is an easily to operate system. I found tluds to be  too fiddly when operating with less than optimum biomass(very dry).

What is a smoke catcher ? 

Ross

 

On Tue, 29 Dec 2020, 12:50 Geoff Thomas, <wind@...> wrote:

Hi Ross, there is always a trade-off between how much char you make and how much heat you make, ie a tlud cookstove mainly uses the timber to cook, and only a small percentage of charcoal at the end of cooking.

Also, if you have a sealed unit, ie not a flame cap kiln, you must have enough pull from your chimney, - if you take too much from your chimney it can’t heat the air enough to create enough draft.

Alternatively you could have a smoke catcher above the kiln, - run it inside your shed, the whole shed will be warm and no breeze

 

There used to be hot water systems that had a double skin chimney, - water in between the skins, circulating to a tank, on top of a house heating wood fired system, - they tended to take too much of the heat but if you allie that with a solar heat source, - Solar driers are so easy and cheap, you just build a square/rectangular enclosure, presumably with waste foam sheets on the inside walls, fill it with 5  litre empty oil containers, only filled with water, and place any old sheets of glass you can scrounge over the top and seal with silicon, tar, or whatever. 

 

It should slope up either north or south, depending on whether you are in the southern or northern hemisphere, so up goes into your drying shed, the black plastic oil containers, - now filled with water, get hot and take quite a while to cool down, thus extending the drying time, and you should circulate the hot water from the double skin section of your chimney (not removing too much heat) into a cheap storage tank, connected to an old car radiator or other heat exchange unit, so as to serve as an alternate air input to the Solar drier, or indeed the main entry (at the bottom of the slope)

 

This can maybe be organised into a 24 hour air movement, with the cheap energy coming from the sun at at least 1000 watts per square meter, and either the chimney heater or both, inlets. - ie if the biochar unit is running 24/7, for simplicity sake, all through the 24 hours so when the heavy lifting, - ie the Solar, kicks in, there is already a lower level circulation going on, so it never stops, - which will be more efficient, - always the moisture will be being removed and not pooling anywhere in the system.

 

Obviously, the situation will be easier if your drying shed is on a slope towards the sun, and as you score more cheap glass, you can extend it down or across as possible.

If on flat ground you will need small fans or the timber is on shelves higher than your Solar Thermal unit.

 

Old car radiators or fridge heat exchangers are often available very cheaply, and if you need a fan to boost airflow, small 12 volt fans from old computers, (coupled with a cheap 2 watt solar panel, - they will run when the sun shines so can be placed so as the sun heats up the air in your dryer only then boosts the natural circulation)  or old 240 volt fans from fridges, are very efficient and use very little power. I particularly like the fridge fans, I have one to cool electronic equipment, very fancy curled blades, uses 8.4 watts, moves several cubic metres /minute, - put up a sign at your local garage supermarket, etc, - “Fridges removed for free”, you will be amazed how many fridges you will score, - a fridge is too big for a suburban car and almost impossible for a single woman, and you will get a percentage that still work, - so can be on-sold for $20. or such to help finance your business, and make life better for the poorer folk around us, - you will probably get that fridge for free anyway when it finally dies.

 - The dead carcasses and doors make a good garden fence, as stores and tools can be stored within, or used as a worm farm, - using the shelves to separate the various stages, the motors will be able to be sold for scrap, - or exchanged for old car radiators, and you will amass a number of bolts, connectors, lights, relays, etc the which may be handy as they are often stainless steel, particularly door hinges, - Heavy Duty, and you can use a few as cupboards in your shed/factory, - moisture proof, or leaving the electric light in it for power tools, welding rods, etc that need low humidity, - they can even be placed outside your building as they are very robust, and easy to thow a bit of old enamel paint on them down the track to last another 20 years, and a row of fridges on an outside wall, with the doors joining the tops, adding between storage,  is both very cheap and very durable storage with easy access.

 

Using materials that are normally waste offers incredible savings and is good for the planet as is the char, - picking up the old fridges gives you an opportunity to mention your char etc. as you are doing the person a favour, - you will need appropriate van/ute/trailor to remove them and a trolley, nothing else.

 

Please feel free to ask further questions, - Cheers,

Geoff Thomas, Malanda, (still partly rainforest) Australia, 4885

 

On 29 Dec 2020, at 5:05 am, Ross Hunt <rossahunt@...> wrote:

 

I am wondering if there is a low cost method to dry wood from waste heat from production of biochar. All wood sources here are wet and we are not allowed to burn in the dry season

I found a comment that  the Adam retort dries wood ?

How does an Adam kiln work ?

Ross 

Vancouver Island ( formerly rain forest)

 


--
Nando Breiter
http://biochar.info
CarbonZero Sagl
Astano, Switzerland

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