# (Incineration) furnance prototype



## orvi (Apr 14, 2022)

So after a long time, I finally get the suitable drum at my workplace (discarded - rusty inside, but perfect for me) and take it home with me 
Old Merck HPLC solvent drum. Not stainless steel, but definitely not just ordinary weak iron. Cutting it with scissors was bit painful. I forgot about existence of angle grinder  

I planned to use larger drum (this is 25 L), double insulation from mineral wool (rated for 1400°C, 2cm thickness). This bring the inner diameter to acceptable 23 cm. On the top, lid is also insulated and insulation fixed on place with kanthal wire (to resist flame on inside). On the top, I also made an afterburner stage, from smaller can. This has also one layer of insulation to retain the heat necessary for complete burning of the stuff. Small hole is also punched on the side for later installation of second small burner with pipe from compressor, to supply oxygen for complete combustion.

I plan to test it soon, with 0,7 kg lot of DIP ICs (old stuff), and see how it will go in terms of completeness of combustion and smoke. I need to somewhat figure out good air supply. But I think with testing, this will work as intended. When I purchase better burner and install it to the oposite side of the drum, together with present one, should be enough also for smelting. But now on full heat, I assume from the colour that it was max. 900°C inside.


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## Gwar (Apr 14, 2022)

Looking forward to the results !


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## kurtak (Apr 15, 2022)

orvi said:


> I plan to test it soon, with 0,7 kg lot of DIP ICs (old stuff), and see how it will go in terms of completeness of combustion and smoke.


*VERY nice* orvi !!!

Looks like you have done your research on* PROPER* incineration

I "assume" you have read some of what 4metal, myself & others have posted about "proper" incineration to come up with your design/build --- *job WELL done* !!!

As long as your burner flame enters the burn chamber at an angle so that you get a cyclone action of the flame swirling around in the burn chamber you should get near complete *(if not complete)* destruction of the toxic gases !!!

I "assume" you have read what I posted here (& if nothing else I am posting the link here for others to read)









Separating all metals from carbon and organics


Hi All, Was wondering if someone with a little more knowledge - and who may have tried it - would be able to advise. I have stacks of PCB boards, cell phone boards, IC chips etc etc and each has it's own "best practice" way of extracting the precious metals from it. Many topics like that on...




goldrefiningforum.com





Agan --- *Job WELL done* 

Kurt


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## justinhcase (Apr 15, 2022)

Quarts wool and refractory ceramic fiber are considered "possibly carcinogenic to humans".
They degrade very quickly in a furnace or incinerator environment and spit out clouds of very small particles that will settle in your lungs and never leave.
So it is very important to always at the very least use a Rigidizer but much preferably a thin layer of a cast refractory cement.
It takes a little more time but will last for decades and save a lot of fuel with the increased insulation.








Single Intratracheal Quartz Instillation Induced Chronic Inflammation and Tumourigenesis in Rat Lungs - Scientific Reports


Crystalline silica (quartz) is known to induce silicosis and cancer in the lungs. In the present study, we investigated the relationship between quartz-induced chronic inflammation and lung carcinogenesis in rat lungs after a single exposure to quartz. F344 rats were treated with a single...




www.nature.com


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## kurtak (Apr 15, 2022)

justinhcase said:


> Quarts wool and refractory ceramic fiber are considered "possibly carcinogenic to humans".
> They degrade very quickly in a furnace or incinerator environment and spit out clouds of very small particles that will settle in your lungs and never leave.
> So it is very important to always at the very least use a Rigidizer but much preferably a thin layer of a cast refractory cement.
> It takes a little more time but will last for decades and save a lot of fuel with the increased insulation.
> ...


YES - I absolutely agree - in fact that had crossed my mind with the intent to post "how to" instructions tomorrow (when I will have more time for detailed instructions)

Kurt


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## 4metals (Apr 15, 2022)

I always preferred to use about 2” of castable refractory with stainless steel needles cast in the mix for reinforcement. If you put a sonitube type cardboard cement form on the inside when you cast it, it is rather easy to
do. And the first time you use it the cardboard burns off leaving a beautiful solid refractory cement lining.


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## orvi (Apr 15, 2022)

kurtak said:


> *VERY nice* orvi !!!
> 
> Looks like you have done your research on* PROPER* incineration
> 
> ...


Yes, I read multiple threads here, and that design is not from my head completely  built with what I have, searching for suitable size and temp. rating of the wool was bit painful, but luckily, friend of mine provided me with like 4 meters roll of the good stuff for very good price 
Thanks 


justinhcase said:


> Quarts wool and refractory ceramic fiber are considered "possibly carcinogenic to humans".
> They degrade very quickly in a furnace or incinerator environment and spit out clouds of very small particles that will settle in your lungs and never leave.
> So it is very important to always at the very least use a Rigidizer but much preferably a thin layer of a cast refractory cement.
> It takes a little more time but will last for decades and save a lot of fuel with the increased insulation.
> ...


Yes, I consider this and wear respirator when working with the wool, as well as when using the furnance.

I am bit lost with how it should be installed. I have the furnance already built. I get it like: make good consistency slurry and coat the insides of furnance with a thin layer, let it dry and then fire the furnance to set it.


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## justinhcase (Apr 15, 2022)

orvi said:


> Yes, I read multiple threads here, and that design is not from my head completely  built with what I have, searching for suitable size and temp. rating of the wool was bit painful, but luckily, friend of mine provided me with like 4 meters roll of the good stuff for very good price
> Thanks
> 
> Yes, I consider this and wear respirator when working with the wool, as well as when using the furnance.
> ...


Much as 4metals advised you simply put a former inside your combustion chamber and cast your cement as you would any other window sill or a garden step.
I sometimes cut some small blocks from commercial fire brick and use them to ensure an even space all around the former.
4Metals 2" wall will be very effective for quite a good-sized furnace, If you are pushed for space you can reduce that wall down quite a bit which is more likely to crack and need maintenance.
But then just render the inside as you do a wall.
I normally cast the floor first then the walls, if there is any place the cement did not flow very well to it is not a problem as that can just be filled in as you would any other standard render.
Hell, they fire refractory cement out of old Martini-Henry rifles to fill gaps in the large furnaces so they do not have to close them down.
So a little play-doh on a small unit like yours is not very difficult and quite fun.


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## orvi (Apr 15, 2022)

justinhcase said:


> Much as 4metals advised you simply put a former inside your combustion chamber and cast your cement as you would any other window sill or a garden step.
> I sometimes cut some small blocks from commercial fire brick and use them to ensure an even space all around the former.
> 4Metals 2" wall will be very effective for quite a good-sized furnace, If you are pushed for space you can reduce that wall down quite a bit which is more likely to crack and need maintenance.
> But then just render the inside as you do a wall.
> ...


Thanks very much for clarification, now I get it correctly. 
Sometimes I have trouble to understand things in english


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## justinhcase (Apr 15, 2022)

orvi said:


> Thanks very much for clarification, now I get it correctly.
> Sometimes I have trouble to understand things in english


Very glad to have been of some small assistance.
J


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## pwm97128 (Apr 16, 2022)

Air supply for burner: I have had good success using garage sale CPAP machines. They provide continuous constant pressure variable from 4psi to 20psi. Best of all they are quiet and have reliable components due to medical manufacturing specifications. Programming can be tricky, but YouTube videos are available for most manufacturers. I feed three CPAPs into a collector so I can vary the air volume by adding units rather than modifying the PSI setting on a single machine.

Nice setup.

Best regards


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## AustAuScrap (Apr 18, 2022)

Thanks PWM for hint re CPAP machines, and especially the work around re volume control - I will try with my next burn


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## snoman701 (Apr 18, 2022)

The fiber is best installed by folding into 3-4" tall V's where the point of the V is towards the center of the diameter. The back of the V should be approximately normal if not puffed up density, with the point being compressed to make it all hold together. Then you coat the inside of the diameter with any castable refractory. That's how we used to make all of our glory holes for glassblowing.


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## orvi (Apr 19, 2022)

snoman701 said:


> The fiber is best installed by folding into 3-4" tall V's where the point of the V is towards the center of the diameter. The back of the V should be approximately normal if not puffed up density, with the point being compressed to make it all hold together. Then you coat the inside of the diameter with any castable refractory. That's how we used to make all of our glory holes for glassblowing.


Nice hack. If I knew this before installation... but nevermind, it hold together OK. For now 



pwm97128 said:


> Air supply for burner: I have had good success using garage sale CPAP machines. They provide continuous constant pressure variable from 4psi to 20psi. Best of all they are quiet and have reliable components due to medical manufacturing specifications. Programming can be tricky, but YouTube videos are available for most manufacturers. I feed three CPAPs into a collector so I can vary the air volume by adding units rather than modifying the PSI setting on a single machine.
> 
> Nice setup.
> 
> Best regards


Thanks for suggestion, but unfortunately, my budget is not that big. Altough it would be nic to make something more high-level. I am intending to use air blower for inflating matresses. Simple 12 V motor, 450 L air/min, so I will attach it to the PWM regulator to be able to regulate airflow. This also help to reduce overheating.


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## GoIdman (Apr 19, 2022)

orvi said:


> Thanks for suggestion, but unfortunately, my budget is not that big. Altough it would be nic to make something more high-level. I am intending to use air blower for inflating matresses. Simple 12 V motor, 450 L air/min, so I will attach it to the PWM regulator to be able to regulate airflow. This also help to reduce overheating.


If I may say, you could simply use an older hair dryer plugged into 220V with or without the heating element.....Usually it has 2 or 3 speed steps. If you disconnect the heating element it will use very little (few watts) of electricity and since it uses turbine blades it will last forever.

Find one at the flea market or online for a few euros like the one in the picture.


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## butcher (Apr 19, 2022)

DC motors do not need pulse width modulation regulation to control their speed, all you need is a variable resistor bank or something similar to lower or change the voltage to the motor.

Small DC motors can be run from an alternating current source by going through a bridge diode to convert the AC current to DC current.

Small AC motors speed can be varied with a Triac type circuit such as using alternating current lamp dimmer switches.


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## orvi (Apr 19, 2022)

butcher said:


> DC motors do not need pulse width modulation regulation to control their speed, all you need is a variable resistor bank or something similar to lower or change the voltage to the motor.
> 
> Small DC motors can be run from an alternating current source by going through a bridge diode to convert the AC current to DC current.
> 
> Small AC motors speed can be varied with a Triac type circuit such as using alternating current lamp dimmer switches.


Yes, I know that. But once I bought a lot of 10 pieces of PWM regulator modules from China... Cheap, working, straightforward... No need for heatsink under 8 A. So I use these, potentiometer included, only to mount them in place 

I like to work with DC and low voltage, it is much easier to customize and regulate the thing without excessive appliances around. Just one plug-power supply with inside built PWM, and that´s all


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## Liquidau (Nov 30, 2022)

snoman701 said:


> The fiber is best installed by folding into 3-4" tall V's where the point of the V is towards the center of the diameter. The back of the V should be approximately normal if not puffed up density, with the point being compressed to make it all hold together. Then you coat the inside of the diameter with any castable refractory. That's how we used to make all of our glory holes for glassblowing.


Would you have any sketches or pics of this? Sounds great but i'm having trouble picturing it....


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