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Open Source Microwave Sonic Biofuel reaction chamber

Open Source Microwave Sonic Biofuel reaction chamber

Open Source Microwave Sonic Biofuel reaction chamber

(OP)
I have been looking at ways to process waste streams into a usable fuel source for quite some time.  There are many ways to do this, but nothing Low Cost, clean, and efficient.  From all my research I have extrapolated a potential solution but I am an infant in the microwave realm and need help to see if it is feasable.

I have focused on rubber because it is hard to process, so if we can process that then everything else should also work.

Some research that I followed:
http://www.nathanwelton.com/stories/science/tires.html
http://www.scielo.br/scielo.php?pid=S0104-14282006000400004&script=sci_arttext

I am including a sketch that I drew up of my vision of a microwave sonic reaction chamber. Please let me know what you think and if it looks doable then I would like to see this technology in the public domain to reduce the worlds reliance on petroleum.

RE: Open Source Microwave Sonic Biofuel reaction chamber

Your microwaves can be focused only if the loss is minor in the material. If the loss is minor, you can't heat it much. A bit of a quandary.

you could setup antenna feeds and elliptical reflector shapes on your walls to greatly heat your material in the center of your vessel. But phase control would probably not be useful based on your diagram. Microwaves heat from the outside in. You can focus them, but not to super heat material quickly.

MRI machines at Duke University use focusing for slight heating of cancerous tumors inside a body, but the key part is "slight" heating.

Are you proposing this to someone who has funding?

kch

  

RE: Open Source Microwave Sonic Biofuel reaction chamber

(OP)
I am primarily concerned with the first intersection of the beams, it could be very close to the outside of the process material, first traveling through the ceramic lining (should be little loss at this point).  If using by using phase shift to cancel and strengthen the microwave signal at the intersection, can I create ultrasonic pulses that are strong enough to agitate the process material plus break the long hydrocarbon chains?

The shell and ceramic lining can be modified to make a thinner cavity if needed.

Funding:  Currently I have no direct project to put this against, but I do work with an automotive recycler that is paying to remove auto fluff.

RE: Open Source Microwave Sonic Biofuel reaction chamber

You can make a very high intensity beam using an elliptical ceramic filled reflector. You can just use a waveguide that ends at your inner tube, it'll create arcing with enough power on your tube wall. That'll set an rf power limit.

Microwaves move electrons creating friction and thereby heating. You can only heat material. It's essentially a microwave oven that's concentrated.

If you need to super heat a tube of material, you can do that with microwaves.

Ultrasonics use 10,000 to 100,000 cycles per second sound waves and are used to create friction for heating (human cancer heating).
Microwave ovens use 2,450,000,000 cycles per second.

This is a million dollar development job minumum.

kch

RE: Open Source Microwave Sonic Biofuel reaction chamber

(OP)
"This is a million dollar development job minumum."
So you say it's possible!

It is not just to super heat the material, you only need to get above 475 F, the ultrasonic creates a shearing effect to the hydrocabon chains, the heat makes them more volatile.

RE: Open Source Microwave Sonic Biofuel reaction chamber

I like that movie too Jim Carey.

So will you propose both ultrasonic and microwave in the same chamber?

kch

RE: Open Source Microwave Sonic Biofuel reaction chamber

(OP)
Set the two microwave beams to cross paths and phase shift one beam by 180 degrees from the other beam to cancel both signals, then synchronize them back to add the two signals together at the intersection point.  Go between the phase shift and sync. modes with a frequency in the ultrasonic range.  In effect we will be using pulsed microwaves to create an ultrasonic wave.

RE: Open Source Microwave Sonic Biofuel reaction chamber

If intersecting microwave beams could create 'an ultrasonic wave', then it would be (for example) annoyingly loud anywhere near cell phone towers.

 

RE: Open Source Microwave Sonic Biofuel reaction chamber

The microwave beams only move the molecules a tiny fraction compared to the distance an ultrasonic moves the molecules. There's be no ultrasonic action when using RF energy as opposed to air motion energy. You'd just average the heating amount by changing the phasing of the signals.

kch
from http://physics.suite101.com/article.cfm/how_do_microwave_ovens_work
As the water molecules rotate, they bump other molecules causing them to begin moving randomly. The process is like frictional heating. Microwave energy converts to heat energy by causing the molecules in food to increase the speed of their random motions.

Read more: "How Do Microwave Ovens Work? Heating Water Molecules in Food with Electromagnetic Waves |


 

RE: Open Source Microwave Sonic Biofuel reaction chamber

(OP)
Without enough power and precision I doubt it would be detectable or likely.  With enough power and precision they should act as regular waves and you should be able to cancel or sum the result.

RE: Open Source Microwave Sonic Biofuel reaction chamber

You can produce physical vibrations by mixing two rf signals, but you need to mix them in a non-linear media.  Air is not such a media.

www.MaguffinMicrowave.com

Maguffin Microwave wireless design consulting

RE: Open Source Microwave Sonic Biofuel reaction chamber

(OP)
Biff44,
The mixing medium is going to be the process material, recycled waste (plastic, rubber, and misc. stuff).  Do you know of any examples or literature on combining two MW signals to produce sonic waves?

PS:  To be clear all information in this thread is intended for public knowledge, not locked up and restricted to licensed commercial use.

RE: Open Source Microwave Sonic Biofuel reaction chamber

I do not remember where I saw it, but somebody was making a loudspeaker by mixing two rf beams in a non-linear media.  It had very broad and flat bandwidth.  I do not remember any of the details, though.

www.MaguffinMicrowave.com

Maguffin Microwave wireless design consulting

RE: Open Source Microwave Sonic Biofuel reaction chamber

Sounds like a Theremin to me!  

John D

RE: Open Source Microwave Sonic Biofuel reaction chamber

Oddly enough, I am working on some thereamins right now!  But, no.  A theramin uses two rf signals, a mixer, and a loudspeaker to move the air.

I am talking about moving the air without the use of a loudspeaker.

www.MaguffinMicrowave.com

Maguffin Microwave wireless design consulting

RE: Open Source Microwave Sonic Biofuel reaction chamber

Interesting idea, seems like it would have similar problems that many high efficiency alternative energy systems have. A lack of scalability. It would be very difficult to build a reactor that would have an economically viable throughout & conversion efficiency.

www.custommicrowave.com
Space Qualified Multifrequency Antenna Feeds - Advanced Microwave & Mechanical Design - Full Catalog of Standard Product

RE: Open Source Microwave Sonic Biofuel reaction chamber

Oops, typo.. meant Throughput. Best of luck on your endeavor!

www.custommicrowave.com
Space Qualified Multifrequency Antenna Feeds - Advanced Microwave & Mechanical Design - Full Catalog of Standard Product

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