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Low Power Microwave Heating

Low Power Microwave Heating

Low Power Microwave Heating

Looking for some direction to info on using low power microwave
devices (small magnetrons? transistor type components? etc.) to heat
a mixture of water and ammonia. This is currently accomplished w/ a
300 to 500 watt (120VAC) resistance heating element.

Additionally, I'm wondering if it would be possible to tune the
microwave frequency to preferentially heat the ammonia?

Thanks in advance for any help.

RE: Low Power Microwave Heating

Do you want to heat the dissolved H3N without heating the H2O  ?


RE: Low Power Microwave Heating

Thanks for the reply.

Yes, in some cases, heating the ammonia only would be desirable in order to seperate it from the water.

RE: Low Power Microwave Heating

I think I'm confused, since that shouldn't work that way.  

Microwave energy excites bonds, converting to kinetic energy, wherein you get heat.  Whatever heat is gained by the ammonia will be immediately exchanged with the water.

Assuming that there's much more water than ammonia; you'll waste way more energy for zero net gain.  There's no way to "separate" the solute in this fashion.


RE: Low Power Microwave Heating

IRStuff, you may be correct as far as the heat xfer to the water.

The main objective is to heat the solution to a vapor.

I am looking for info on small microwave emitters to accomplish this heating. Does anyone know of sources of supply for small magnetrons or transistor type microwave emitters?


RE: Low Power Microwave Heating

Why don't you concentrate on problems which may have solution ?


RE: Low Power Microwave Heating

Why do you want to replace a simple, inexpensive device with a complex, expensive device?  

A typical resistance heater runs less than $20, while the enclosure alone for a microwave device will run more than $20 to start with.


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