Is it possible to make a coil burner portable?

[elliotiscool]

I am trying to develop a product that would use a portable heating element.

For example: If I wanted to use a coil burner, is there a way I could make it cordless using let's say a rechargeable battery?

It does not necessarily have to be a coil burner. It just has to been something that can heat up to 400-600 degrees.

Weight is also an issue. I can't have it portable using something the size or weight of a car battery.

Thanks for any help.

 

[Simon Bridge]

Welcome to PF;
Have you canvassed the available products to see how other people have solved the same problems?

A quick google shows lots of entries for "portable coil burner" for sale.
Also lots of portable burners that are not coil burners ... and if you don't restrict yourself to electricity then the field is very wide indeed.

The temperature range (4-600C?) is not much of a restriction (by itself) - a tungsten filament, for eg., can be around 3000C and a car cigarette lighter can be between 800C and 1200C. You will have other design restrictions which will be important.

 

[elliotiscool]

Welcome to PF;
Have you canvassed the available products to see how other people have solved the same problems?

A quick google shows lots of entries for "portable coil burner" for sale.
Also lots of portable burners that are not coil burners ... and if you don't restrict yourself to electricity then the field is very wide indeed.

The temperature range (4-600C?) is not much of a restriction (by itself) - a tungsten filament, for eg., can be around 3000C and a car cigarette lighter can be between 800C and 1200C. You will have other design restrictions which will be important.

Thanks for the response.

I regards to portable coil burners, I have not been able to find one that is truly portable. These "portable" coil burners that are sold in almost any store are portable as in you can pick it up and move it somewhere, but still requires a wall to plug in to. When I saw the watts of these stoves I become a little discouraged because I couldn't come to find a way to make it portable without weighing 75 pounds.

Ultimately this is ideally what I am looking for:
- The burning element is small, around the size of the same coil you see in a hair dryer.
- Be able to burn around 600 degrees Fahrenheit
- Completely portable as in it could ideally use a small battery that is rechargeable.

I have not looked into how a car cigarette lighter is used and will look into it.

 

[Simon Bridge]

As you've seen, the power requirement is the biggest constraint you have.
i.e. you could power a cigarrette lighter off a stack of watch-batteries - just not for very long between recharging.
I'd start, then, by working out the type of portable power supply you'd want to use - find the most powerful one that is as inconvenient as you can possibly put up with. The rest will follow.

 

[elliotiscool]

Thanks for all your help.

I have no electrical engineering knowledge whatsoever besides junior high.
If I were to wire the positive and negative of a 9 volt battery and have both those wires touch the middle of the car cigarette lighter would it create the current that would cause it to heat up?

Also I presume the voltage of the battery would affect how hot the lighter would get? What is a cheap and preferably small attachment I could have that would adjust the amount of electricity going through to affect how hot the lighter got? What about a switch that I could turn that would decrease or increase amount of heat?

Lastly, and much more complicated... Is there a way I could attach a flow sensor in my product that would basically sense air moving through it, that would then have it increase the amount of heating being produced as long as it continues to detect the flow?

 

[berkeman]

I am trying to develop a product that would use a portable heating element.

For example: If I wanted to use a coil burner, is there a way I could make it cordless using let's say a rechargeable battery?

It does not necessarily have to be a coil burner. It just has to been something that can heat up to 400-600 degrees.

Weight is also an issue. I can't have it portable using something the size or weight of a car battery.

Thanks for any help.

Thanks for the response.

I regards to portable coil burners, I have not been able to find one that is truly portable. These "portable" coil burners that are sold in almost any store are portable as in you can pick it up and move it somewhere, but still requires a wall to plug in to. When I saw the watts of these stoves I become a little discouraged because I couldn't come to find a way to make it portable without weighing 75 pounds.

Ultimately this is ideally what I am looking for:
- The burning element is small, around the size of the same coil you see in a hair dryer.
- Be able to burn around 600 degrees Fahrenheit
- Completely portable as in it could ideally use a small battery that is rechargeable.

I have not looked into how a car cigarette lighter is used and will look into it.

Welcome to the PF.

Sorry if I missed it, but what exactly are you looking to heat up? You just want to heat air to 600F? Or do you want to heat some other object with your heater? I'm not familiar with the term "coil burner"...

 

[Simon Bridge]

A "coil burner" is usually something like this:
http://www.ebay.com/itm/Portable-Electric-Coil-Burner-Cooktop-Countertop-Single-Hotplate-Cooker-Warmer-/221083296593@elliotiscool:
I have been assuming that the temperature is of the coil itself rather than the thing to be "burned". Knowing what it is for would certainly help :)

The energy dissipated by the burner depends on both the voltage across it and the current through it. Perhaps this will help you understand what you need:
http://en.allexperts.com/q/Science-Kids-3250/small-heating-coil.htm

 

[MATLABdude]

Unfortunately, for the energy density afforded by any battery technology currently available, you'd be better served by a kerosene or even propane burner (and that's what most campers use, aside from packing a small axe / hatchet and chopping up kindling or branches)

 

[russ_watters]

Without saying what you want to heat up and for how long, we can't really say how to power it.

 

[russ_watters]

I have no electrical engineering knowledge whatsoever besides junior high.
If I were to wire the positive and negative of a 9 volt battery and have both those wires touch the middle of the car cigarette lighter would it create the current that would cause it to heat up?

Car cigarette lighters run on 13.5 V, so a 9V battery would probably cause it to heat up, but not much.

Also I presume the voltage of the battery would affect how hot the lighter would get?

Yes.

What is a cheap and preferably small attachment I could have that would adjust the amount of electricity going through to affect how hot the lighter got? What about a switch that I could turn that would decrease or increase amount of heat?

There are a lot of ways. Multiple batteries with switches to change the voltage. A voltage regulator.

Lastly, and much more complicated... Is there a way I could attach a flow sensor in my product that would basically sense air moving through it, that would then have it increase the amount of heating being produced as long as it continues to detect the flow?

A thermostat. Sure.

 

[elliotiscool]

Sorry if I missed it, but what exactly are you looking to heat up? You just want to heat air to 600F? Or do you want to heat some other object with your heater? I'm not familiar with the term "coil burner"...

A "coil burner" is usually something like this:
http://www.ebay.com/itm/Portable-Ele...-/221083296593

The ebay link is exactly what a coil burner is.
The heating element attaches to another part in which it heats up. So when I say that I need my invention to heat up to 500F for example, I mean that I need the cigarette lighter, or coil, etc. to reach that temperature.

Without saying what you want to heat up and for how long, we can't really say how to power it.

I have been assuming that the temperature is of the coil itself rather than the thing to be "burned". Knowing what it is for would certainly help :)

The energy dissipated by the burner depends on both the voltage across it and the current through it. Perhaps this will help you understand what you need:
http://en.allexperts.com/q/Science-K...ating-coil.htm

Unfortunately I can't give an exact description, but I can give a close example. Let's say I had a metal cylinder (those tall metal coffee mug things for example.) Inside of it I had this heating element that reached a temperature of 600F. At the end of the cylinder it would attach to another part that I was trying to heat up.

As far as length of time it needs to be hot, the answer is as long as possible. 1 hour+ is the absolute minimum. 2 or 3 hours would be fantastic. At the same time it cannot be too large. Like my coffee mug example, I wouldn't want it any larger than that. The battery needs to be rechargeable.

And thank you for the link. It definitely helped me understand.

Unfortunately, for the energy density afforded by any battery technology currently available, you'd be better served by a kerosene or even propane burner (and that's what most campers use, aside from packing a small axe / hatchet and chopping up kindling or branches)

Thanks for the input. I have looked into this before but came to the conclusion that with consideration of the amount of gas needed + need to refill, and then the fact I need my product to stay fairly small and inexpensive; that this would not work. If there is something you think I am missing here please do let me know. If there is a way to keep it small, cheap, and lit for a very long time I would look into it further!

 

[russ_watters]

The ebay link is exactly what a coil burner is.

The heating element attaches to another part in which it heats up. So when I say that I need my invention to heat up to 500F for example, I mean that I need the cigarette lighter, or coil, etc. to reach that temperature.

You don't need to know temperature, you need to know heat. Temperature is not heat: Your description is incomplete at best and is not enough to help answer your main question (how to power it).

The filament of a AAA battery powered flashlight gets much hotter than 500F, for example, but I doubt that that will satisfy your needs.

More to the point, there is a vast difference between the energy/heat absorbed and released by a cigarette lighter and a coil burner. If the cigarette lighter meets your needs, then the power requirement is around an order of magnitude lower than you seem to think it is.

So: What matters isn't the temperature, but how fast you remove heat from the burner. Do you know how fast you are removing heat from the burner?

Unfortunately I can't give an exact description, but I can give a close example. Let's say I had a metal cylinder (those tall metal coffee mug things for example.) Inside of it I had this heating element that reached a temperature of 600F. At the end of the cylinder it would attach to another part that I was trying to heat up.

How big of a cylinder? Is it filled only with air? Is it oriented vertically? Is it insulated? How hot do you want the object to get? How fast? From what starting temperature? What is the specific heat capacity of the object?

We cannot help you unless you can help us figure out (or just tell us) how fast you need to produce heat.

 

[elliotiscool]

You don't need to know temperature, you need to know heat. Temperature is not heat: Your description is incomplete at best and is not enough to help answer your main question (how to power it).

The filament of a AAA battery powered flashlight gets much hotter than 500F, for example, but I doubt that that will satisfy your needs.

More to the point, there is a vast difference between the energy/heat absorbed and released by a cigarette lighter and a coil burner. If the cigarette lighter meets your needs, then the power requirement is around an order of magnitude lower than you seem to think it is.

So: What matters isn't the temperature, but how fast you remove heat from the burner. Do you know how fast you are removing heat from the burner? How big of a cylinder? Is it filled only with air? Is it oriented vertically? Is it insulated? How hot do you want the object to get? How fast? From what starting temperature? What is the specific heat capacity of the object?

We cannot help you unless you can help us figure out (or just tell us) how fast you need to produce heat.

I lack knowledge when it comes to this but hopefully this answer will give you a better idea.

Lets use the coffee mug example: http://i00.i.aliimg.com/photo/v0/379750484/16_oz_metal_mug_with_handle_office.jpg
That is a very similar shape and size to what the product looks like from the outside.
Put maybe 8 tiny holes the size of the plastic part of a thumb tack on the sides. It is made only of thin metal. No other insulation. Nothing else inside it besides the parts necessary to make the heating element work. The cylinder stands vertically. The top is closed. The bottom is open but the object that I am trying to heat using the heating element attaches to it, so the only ventilation will really be those holes made.
The heating element will be about an inch away from it. The product will usually be used outdoors. So the temperature of the environment before using it will be around 30-100F, with 0F and 110F being fairly extreme outliers.

The object I am trying to heat holds heat very well as it is usually ceramic. The temperature it needs to reach is somewhere between 210-250F. Without absolutely disclosing my idea for the internet I am trying to replicate what happens to it when you put coals very near it or on top of it.

Now let's say there is hole that goes through my product in which air will move through. When air moves through the coal is causes it to rise in temperature temporarily, which I also need it to do. Thus why I was asking about having some sort of flow sensor that would cause my heating element to increase in temperature when it detects air flow.

The amount of time needed to heat this object does not have to be very precise. If necessary it can take up to 5 minutes. Keep in mind I want the heating element to continue staying on so if the temperature of my object changes maybe 20-30 degrees higher within an hour due to prolong heat, that is actually desired since it replicates what the coals would do. I want this heating elements battery to last as long as possible. If it can last 2 hours, cool. If it can last 10 hours, AWESOME.

 

[berkeman]

Do you need the ventilation holes for something? That's going to waste a lot of heat.

 

[sophiecentaur]

You don't seem to be getting the message about this. What counts is Energy. If you need to heat up a mug of water (0.5l) by about 40degreesC then you would need 4200 X 40 X 0.5J =84kJ. That would mean that a 6V battery would need to give 5A for 46minutes. That would be a pretty massive battery. If you wanted to heat up 10g of iron by the same amount (i.e. raise its temperature), you'd be talking more like 200J - which, at 5A and 6V, would take 6seconds.
There is no answer until a proper question has been asked. If you can't tell us the detailed amount of energy needed then you need to do the sums yourself. It would be better to do some experiments using a bench power supply first and find how much power you need but the only battery powered sources of heat that you can get tend to be water heaters for making tea in a car (like my first example) and battery powered soldering irons which last no time at all on one charge.

A much more effective source of portable heat is a gas torch.