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speeding up a compost pile
Moderators: AmyCowen, kgudger, bfinio, MadelineB, Moderators
-
mmcmindes
- Posts: 1
- Joined: Sun Nov 28, 2010 5:40 am
- Occupation: Parent of 7th grade student
- Project Question: My daughter is interested in creating an indoor environment (in an aquarium) that we can test the SunChips 100% compostable chip bag and see how it works. We are willing to use heat lamps to maintain a constant temperature (as it is below freezing outdoors). The bag says it composts in 13 weeks (www.SunChips.com) but we only have 11 weeks. any ideas?
- Project Due Date: Mid February 2012
- Project Status: I am conducting my experiment
speeding up a compost pile
My 7th grade daughter wants to simulate the action of the 100% compostable Sun Chips bag as it composts. We need to do this indoors, as it is winter here. We are planning on using an empty aquarium (40 gal) and heat lamp to keep the temperature high. Any suggestions? The website, www.sunchips.com, says it take 13 weeks to do this. We only have 11. Help?!
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sunmoonstars
- Expert
- Posts: 424
- Joined: Fri Dec 12, 2008 3:47 pm
- Occupation: Platform Manager - Biologics
- Project Question: n/a
- Project Due Date: n/a
- Project Status: Not applicable
Re: speeding up a compost pile
Hi,
This is an awesome project! I hope your daughter has a lot of fun with this one.
So, first, did you consider how you are going to maintain a 130F temperature? What do you plan to do if the temperature inside the heap starts to get over 130F? This could get tricky - and Sunchips says it should take 12-16 weeks to decompose. They didn't say why there would be so much variation. http://www.sunchips.com/resources/pdf/S ... Scenes.pdf
They did test it two different ways. They got fastest results (13 weeks, seemingly consistantly) when they added other compostable materials and did not control the temperature (much like someone would do at home). Since you are trying to beat the 13 week mark, this is the approach I think you should be using. You can still use the heat lamp to get it going, or if you plan to store this thing in the garage in case it gets stinky.
The link I gave also gives some ideas for optimization. I think one of the most important is going to be getting the internal temperature to 130+ quickly and making sure it stays at least that high, have the best mix of other compostables and making sure it is a good enough size. Another idea is to use some compost material from an established compost - call some garden or landscapers for this! You may also be able to speed it up by increasing the surface area of the bag (cutting it into smaller pieces).
Even if the bag is not 100% composted at the end of the experiment, that may be ok! What is the question your daughter is trying to answer with her experiment? Maybe she could ask: "Will doing X speed up the decomposition of this bag"? Or maybe "Will cutting the bag up into smaller pieces speed decomposition?"
This is an awesome project! I hope your daughter has a lot of fun with this one.
So, first, did you consider how you are going to maintain a 130F temperature? What do you plan to do if the temperature inside the heap starts to get over 130F? This could get tricky - and Sunchips says it should take 12-16 weeks to decompose. They didn't say why there would be so much variation. http://www.sunchips.com/resources/pdf/S ... Scenes.pdf
They did test it two different ways. They got fastest results (13 weeks, seemingly consistantly) when they added other compostable materials and did not control the temperature (much like someone would do at home). Since you are trying to beat the 13 week mark, this is the approach I think you should be using. You can still use the heat lamp to get it going, or if you plan to store this thing in the garage in case it gets stinky.
The link I gave also gives some ideas for optimization. I think one of the most important is going to be getting the internal temperature to 130+ quickly and making sure it stays at least that high, have the best mix of other compostables and making sure it is a good enough size. Another idea is to use some compost material from an established compost - call some garden or landscapers for this! You may also be able to speed it up by increasing the surface area of the bag (cutting it into smaller pieces).
Even if the bag is not 100% composted at the end of the experiment, that may be ok! What is the question your daughter is trying to answer with her experiment? Maybe she could ask: "Will doing X speed up the decomposition of this bag"? Or maybe "Will cutting the bag up into smaller pieces speed decomposition?"