Vertical hotplates IC incinerator - will it work?

I had a very good results with incineration of IC chips on a electric hotplate. The IC chips are incinerated very good on it.





So i have this idea for making it much more efficient - setup with two vertical hotplates and between them a "ring" that could be opened on top to put the chips inside and one on the bottom to take them out after incineration.

That way (because the "ring" will seal the area where chips are, but not making vacuum) higher temperatures will be provided, and also more space for chips. Another benefit is that it is easy portable.

Do you think that this is good idea and will it work considering much higher temperatures and vertical position?

Alex

You need access for air to incinerate the carbon in the chips. In the vertical design, air might be the limiting factor.

Göran

And some way to prevent overheating with two plates facing each other and nowhere for heat to escape. Probably beyond the original safe operational designs. That could be one serious meltdown. :twisted:

Dave

Thank you for replies, i think i found solution for lack of oxygen and partly for overheating.

First i would make a steel frame like in the picture.

I am not sure if welding is good idea because i don't know melting point - maybe it is better to connect this frame together with massive iron or steel screws.



After that i would pick some proper steel mesh to weld or screw on the outer surface of the ring like this.

I think this would solve problem related with oxygen.

I think in part your hot plate worked so well because of the exposure to the surrounding air. With the enclosure your looking into I believe it will slow down incineration times by a quite a lot. If you are set on using something electric why not look into a griddle. They are basically a larger version of a hot plate. I use one sometimes when I have more than one process going and have had as many as four beakers heating at one time.

Another thought would be a toaster oven or rotisserie oven. You could supply fresh air with a fan from a computer. The rotisserie oven would need a catch pan as the chips will fall apart as they rotate. Done right, it could speed up incineration times, I think.

Shark said:

I think in part your hot plate worked so well because of the exposure to the surrounding air. With the enclosure your looking into I believe it will slow down incineration times by a quite a lot. If you are set on using something electric why not look into a griddle. They are basically a larger version of a hot plate. I use one sometimes when I have more than one process going and have had as many as four beakers heating at one time.

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Thank you Shark, i never tried a griddle... I was thinking that griddles could not have such high temperatures like hot plates (red hot).

Mine will reach the same temperatures as my hot plate, around 400*F is what I have shot the temperature at. I have never tried to process chips on either one, but have seen small bits of broken chips turn white on them. The older type hot plates with the exposed elements may work even better as my hot plate has a steel cover made on to it. Might be able to use a thin sheet of metal across two hotplate with those exposed elements. Or a Pyroceram dish may work.

This is experiment for testing "lack of air/oxygen" while incinerating. I covered IC chips with CD-ROM metal plate and this is how it looks under after couple of hours. Only a few of IC's on top that had direct contact with metal plate stays black (pyrolized) - the rest of it is incinerated very well.




And after little shaking inside of glass jar - the result is very good - almost all is very soft and became a fine ash very soon.




So i think that this experiment proves that lack of air/oxygen would not be a problem (after making steel mesh frame like i described above). Maybe i am wrong but i think that making device that heats on both sides will save much of time needed for incineration and at least double more of IC's could be incinerated at once (comparing it with just one hot plate).

And for preventing overheating i would use adequate materials - for inner "ring" i woud use two Stainless Steel Circular Flat Flanges.



And i would integrate heat sensor just in case - to control the temperatures - i already have a heat sensor that i modified to run on AC power instead on batteries.

i am just thinking out loud - maybe all of this is not a good idea - but sure it would be great if there is a way for making electric furnace that can incinerate much larger quantity of IC's at much less time.

Shark, thank you for ideas - i will try one as soon as i find to buy something similar.

How long did you leave the chips on the hotplate before they incinerated? I think this looks very interesting, your results are impressive. Keep posting.

bigpagoda said:

How long did you leave the chips on the hotplate before they incinerated? I think this looks very interesting, your results are impressive. Keep posting.

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Thank you. Now, when is cold outside - it take about 1.5-2 hours for IC's to become white and fluffy. At summer time about 1 hour - so external temperature is one factor.

Another factor is are they covered or not. If i cover the IC's with CD-ROM metal case like in picture above - it take less time because the case is keeping higher temperatures beneath.

Another factor is how strong hot plate is - more watts means higher temperature. In time - hot plate will become weaker...but it is very durable - it lasts for very long time before hotplate cracks - like i described in this thread: https://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=25300

Another factor is are you leave IC's intact or you turn them to other side after some time. Turning them to other side as soon down side gets white on one side saves a time, but requires work.

Another factor is how much of IC's you have at one time - more you have - it is more time needed for upper levels to turn white...but it works also very well (if covered with metal plate).

Then, size of hot plate plays high roll - larger hotplate - more IC's can fit.


For me it is much much better and cleaner way comparing with propane torch incineration, and also much less work. From a economic point of view - it all depends of your situation - price of electric power vs propane price.


This is microscope pictures of gold bonding wires and ash after 3 hours of incineration - very, very good results.

Cover chips with a piece of kaowool to prevent heat loss.