windmill composter

[Branch]

Re: windmill composter / Minto\'s Wonder Wheel

Just found a great website to learn about composting.
http://www.oldgrowth.org/compost/compost.html#decomposition
More info
http://www.a-horizon.com/compost/compost_menu.html

Branch

<P ID="edit"><FONT SIZE=-1>Edited by Branch on 06/27/01 02:20 PM (server time).</FONT></P>

 

[RPM]

Re: windmill composter / Minto\'s Wonder Wheel

Re: Branch's solutions

I like the idea of a barrel in a barrel for the heat exchanger. Couple of suggestions there - I had discounted this idea too quickly I guess because I assumed that all barrels around this size (55 gallon or similar) are the same diameter. Do they come in different sizes or would modification be needed? Also, the barrel that holds the compost should preferrably be a good heat conductor. Steel would be best for heat transfer, but plastic would be better for corrosion resistance.

With regard to the temperature differential. Shading would work - would probably have to put each tank in a vented box as this wheel may get too big to create a shade for the whole thing. Would be pretty easy to construct. The addition of a water spray sounds like an additional source of power would be needed (well-pump etc.) - might want to stick with the shading.

A compost heap should get up to around 120 degrees or so (after a couple of days). The trick is to then work out how much of that heat can be transferred to one of the rotating tanks. A tank in full sunlight would get above 120 easily - hence the problems in sunlight ...

In fact, there's a potential for the heat source to be sunlight (direct or as JOR EL suggested with a fresnel lens) and then have a cooling apparatus - let part of the problem be part of the solution.

 

[StoneHeartFarm]

Re: windmill composter / Minto\'s Wonder Wheel

I picked up a link through the Weird Science website. This one has quite a bit about different configurations for Minto's wheel.

One of the approaches they are trying is multiple wheels on the same axle. They are also suggesting putting cooling fins on the tanks to aid in reducing the temperature in the off cylinders.

There is one REAL interesting comment though. They are mentioning table top models. It occurs to me that IF you can build multiple wheels on a single axle, and IF you can build a table top model, than why couldn't you built a much smaller machine that the 30' job we've been discussing? I'm thinking something under 8-10 feet tall that could be housed in a common storage shed. Something with multiple wheels say 8-12. That might solve several problems, as the unit would be hidden, and the temperature in the building could be easily moderated to ensure maximum power output. Also, this site is recommending using 1" hard copper tubing to transport the gas from cylinder to cylinder. They are hoping for 6 RPM.

Here's the address (hope I can figure out how to make this link and jump).

SHF

http://users.mildura.net.au/users/egel/tempw.htm

 

[StoneHeartFarm]

Re: windmill composter / Minto\'s Wonder Wheel

Okay, so my brain's burning on this one, trying to figure a way to get more hp and RPM out of a shorter than 30' tower.

I'm imagining this wheel starting to move from a dead stop. If the top and bottom cylinders are precisely at nadir and zenith, then there would be a slight hesitation while gravity undertakes to spin the wheel. As the top cylinder falls, the speed would gradually increase until the maximum speed is reached at the bottom of the arc.

I am assuming that this accelleration phenomenon would occur on each cycle. There would be a slight hesitation of the top cylinder as gravity begins to grab ahold and pull. I beleive this hesitation is partially to blame for the low RPM.

I'm wondering if there is a way around this hesitation. Specifically, think of 2 wheels stacked like and OREO cookie. Imagine each wheel has cylinders around the outside corresponding to the numbers on a clock. Why couldn't the #6 cylinder on the #1 wheel be connected crosswise to the #1 or #2 cylinder on the #2 wheel. The #7 cylinder on the #1 wheel would then connect to the #2 or #3 cylinder on the #2 wheel, and so forth. It seems this would eliminate or reduce the hesitation effect by placing the weight in a more comfortable position for gravity to grab it, without overly sacrificing the height of fall (shall we call this the "head"?).

Also, out of curiosity, what would happen if we applied the heat to cylinder #7 or 8 instead of #6. (In a system plumbed dead opposite). That would offset the heat and cooling sources.

What I'm trying to do is increase HP and RPM to the point where this might wind up being more than just a funny toy for grinding grain or turning compost. (10 to 20 RPM with 25 HP could possibly be geared up to handle a small generator.)

Whatcha think?

SHF

 

[RPM]

Re: windmill composter / Minto\'s Wonder Wheel

Re: How the wheel accelerates (or not)

SHF - I think you will find that it is a fairly smooth process. The transfer of fluid between the tanks would be gradual (filling by condensation) - and this same gradual process would be repeated in all the tanks around the wheel.

 

[RPM]

Re: windmill composter / Minto\'s Wonder Wheel

Re: Multiple wheels on a shaft

I don't think you need multiple wheels. You could just get away with long tanks mounted parallel to the axis of rotation - it's the same effect for a lot less effort. (Instead of a disc rotating, it would now look more like a cylinder rotating about its axis)

You could use some big old gas bottles like they use for welding gases.

 

[RPM]

Probably a good point to summarize the approaches suggested so far:

1. Windmill powered composter (original idea)

2. Water powered composter

3. Electric starter-motor powered composter

4. The 'Rube Goldberg' - combination of using a windmill to gradually load shot into buckets that rotate the drum

5. Minto's Wonder Wheel

Just thought it would be useful to summarize briefly for any new browsers!

 

[Knight9]

Now if only this could be run via solar energy..../w3tcompact/icons/smile.gif If it will compost chickens...it'll compost anything!!

Kevin

 

[Branch]

Re: windmill composter / Minto\'s Wonder Wheel

The original 30' wheel was supposed to put out almost 9hp! That's enough to Hp to spin one humungus pile of compost. The 8' diameter is much more appropriate, I think, for your average non-commercial compost slinger.
By what I found at those websites I posted earlier it seems like 1 rev. per day would be adequate. Speed is not necessary for composting.

Really enjoying the ideas you're all throwing out! Somebody might even build one before the fun of brainstorming wears out.

Branch

 

[StoneHeartFarm]

Re: windmill composter / Minto\'s Wonder Wheel

I'm thinking the HP output is probably a product of the radius of the circle. ie, the greater the radius the greater the leverage of the falling bottles, hence the greater the HP output. If this works anything like the power output from wind dynamos, it would be a progression, so the 4' radius would not be 45% of the 7' radius but something on the order of perhaps 10%. 8' wheel 1 hp? This is all fuzzy math and speculation (but that's okay, the government does it with your taxes /w3tcompact/icons/laugh.gif), and probably couldn't be proven without building one.

I still think the multiple wheel arrangement has some merits. Easier to balance (I'm afraid this might be a biggie), and the loss of one set of cylinders through leakage, etc wouldn't upset the whole apple cart. I'm wondering if, in a multi wheel arrangement, why you couldn't heat the #6, #7 and #8 cylinders on the #1, #2 and #3 wheels (1 on each wheel). This would put all wheels in a different stage of expansion/condensation at all times. I'm also wondering if a faster reacting fluid is available. Something that would boil quicker and condense faster.

What I'm aiming at is being able to use gearing on the 1 rpm pto of this beast to derive 3600 rpm. This means either more hp or greater rpm, since the gearing process would more than eat up the 8.5 hp output. Hence, multiple smaller wheels to increase hp, and small modifications to tweek out additional RPM.

You guys get me a way to generate electric power off this bad boy and we'll have a composter that will run itself, with a computer probe to figure out when it needs turning and water. /w3tcompact/icons/laugh.gif

SHF