Alternative Heat From Pond Scum





Introduction: Alternative Heat From Pond Scum

About: My favorite quotation is: “All you need in order to accomplish something great is a good idea and not quite enough money.” – Anon I live by that theme, and the ideas just keep coming.

This year our pond has produced an overabundance of algae, and instead of simply trying to do something about the pond scum, I'm trying to figure out how to do something with the pond scum. In addition to using it in the compost bin, I'm making bricks for our wood stove. To do this, I made a brick mold and filled it with muck that I scooped up out of the pond, slopped it into the wooden mold, then let the algae dry into lightweight bricks.
Watch the video of "the burning of the algae."
Not the most flammable substance, but I think I'm on the right track. I'm hoping someone here knows how I can tweak the recipe for these alternative heating bricks so all this pond scum doesn't go to waste.



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    24 Discussions


    1 year ago

    Thought for a second there that you found a use for my ex... lol! You can also stick it in your compost pile if you have an abundance of it and as long as it's not toxic blue-green algae. As for the fire efforts, maybe adding dry grass, straw or small twigs to the bricks and perhaps downsize the bricks for faster and more thorough drying. Same concern for burning if the algae you have is a toxic variety.

    I can't help thinking that the algae may still be wet - it's still very green when you put it on the fire. From my childhood (on a dairy farm making hay) while the plant material is still green, it still has a moderate amount of moisture in it.

    Two tips for "better burning".

    First thing to try is adding something more combustible to the mix.
    Sawdust, coffee grounds, and paraffin are all popular commercial firelog additives.

    Second suggestion would be, forget the "brick" molds, and go for puck, or stick molds.
    It seems, from your video, the main problem you are having is related to mass vs air and heat.
    Increase the air, increase the heat, or decrease the mass.
    In much the same way that split wood burns faster/hotter than whole logs, using a drying form that increases the surface area per ounce of biomass will lead to "better" burns.

    2 replies

    Dryer lint is also a great additive. Even if you don't use a dryer at home you can obtain tons of it for free from laundromats or even a fair amount from friends and family who do use dryers. Also gives new use to something that usually just goes into the trash.

    Great idea for a fuel additive, Kaeldra. Thanks
    I wonder if I could make paper out of dryer lint... Lots of laundromats near my home. : )

    I like this. Very good thinking. I bet all of your burning issues would be solved if these bricks were placed into an enclosed wood burner with good air flow.

    Now thats thinking in differant ways. As for the burning, don't know if this would work any better but give it a try. Take your blocks and make them into charcoal by burning them inside a metal container. The same way you would do with a piece of wood. If this works better you could be on to something big.

    1 reply

    Redneck has a great idea. You can search for "biochar" and there are tons of how-to's and even a bunch of instructables on how to make the stuff and ideas on what to use it for. For an integrated approach on your pond maintenance, you might make some small "activated biochar" blocks/pucks/sticks from the pond scum and use it as replacement filter media for your pond filter. Added bonus, some chemical filtration from the activated carbon media.

    Yes, I see you made an I'ble about making paper bricks for alternative heat:
    Great idea! We may be needing all the alternative energy we can get if the recession continues...

    In a lot of places in the middle east and Asia where wood is scarce they use dung paddies as fuel for burning, and form what I remember they add salt to the dung before drying it so that it burns hotter. I wonder if that would work for your situation as well. If you try it please let us know how it works out.

    3 replies

    Funny you should mention dung patties. The bricks I'm making smell very much like ripe dung. :)

    After posting this instructables, I made another batch with coffee grounds and pine needles blended into the pond muck and, voila, no smell! I'm guessing the coffee grounds neutralized the caca odor. :)

    Stick some removable dowels or items in it so there will be some Holes in the bricks when they dry, they'll burn lots better.

    To improve the burn you could add russian thistle to the mix or something similar see the instructable

    I've been thinking of doing something like this with sawdust from my shop. It would be a free heating alternative in the wintertime.

    1 reply

    Maybe we could do an exchange: you give me some sawdust for flammability, and I give you some pond scum to use as a binding agent. :)

    Thanks for sharing this interesting idea! Have a splendorous day!