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Winter slows composting

26 Apr 2014

10173295_10202676647935551_213056712_nDuring the recent warm-up, I checked on my backyard composters.   I have to admit  that, during the polar vortex of the last few months, I didn’t do much composter turning and, when I tried, I found that the contents were frozen solid!

Basically, the compost is in the same condition it was last fall – which is to say partially composted but nowhere near “garden ready.”  So, my Spring resolution is to get back to composting, to turn the composters daily (so far 5 days in a row) and to have a couple of good batches of compost to report on before mid-summer.

Manure Digestion/Energy Generation

14 Aug 2013

Tuesday, I traveled to Michigan State University (MSU) for the start up of MSU’s South Campus Anaerobic Digester (SCAD). Reportedly, this is the largest such digester in the United States that is owned by a university.

Anaerobic digestion converts organic materials (feedstocks) without oxygen into biogas.

Once fully operational, MSU’s digester will use roughly 17,000 tons of organic waste from MSU and elsewhere nearby to produce biogas that will generate over 2.8 million kWh of electricity per year.

Most of the system’s feedstock will be dairy manure from the MSU Dairy Teaching and Research Center, with some food waste from campus dining halls, fruit and vegetable waste from a nearby Meijer Distribution Center, and fats, oil and grease from local restaurants.

Biogas produced will power a 450 kW combined heat and power system. The electricity generated will power buildings on the south side of campus.  Hot water generated will maintain the digester temperature at 100 degrees F and to help heat other nearby buildings.

The solids and liquid remaining after digestion (digestate) will be pumped to a solid-liquid separator; solids will be composted; the liquid will be stored in the larger tank in the photo and will be applied to the land as carbon-rich fertilizer.

While the technology is proven, MSU will test this digester to see how this can be implemented in a cost-effective manner. The payback at this point is projected to be between 7 and 12 years. There may be many opportunities for these to be located near large farm “hubs” and even as part of municipal wastewater treatment – if they can be operated economically.

Compost Update –

20 Mar 2013

It appears that the winter has slowed down my compost progress – in part because of the cold and in part because I haven’t wanted to stand out in the snow and wind and turn my composters as often as I was before.  I suspect as spring approaches, things will pick up.

In the meantime, a shout out to Envirocycle – the manufacturer of the composters.  I was outside recently on a sunny day and when I turned the composters, the plastic latch on one of them snapped off when the weight of the compost rolled over the door.

I called Envirocycle, explained the situation and they sent me a whole new door with a new and improved metal latch.  I really appreciate it when a company stands behind its products and I look forward to many more years of composting from our kitchen.

Landfill gas and Coca Cola?

7 Mar 2013

As organic wastes in landfills break down, they form methane.  Until recently, that methane either escaped into the air or was directed to a flare to be burned.  Methane was viewed as a nuisance and something that could cause problems if it traveled in the wrong directions.  However, recently landfill operators have been either selling that methane or using it to generate power on site.  This is both economically and environmentally good as a resource is used and methane (which is a much stronger greenhouse gas than CO2) is combusted.

Recently, the EPA documented the numbers of landfills collecting and using methane and those yet to do so. It turns out that Michigan ranks number three in the Nation behind California and Pennsylvania with 39 landfills using landfill gas and only eight left to do so.

Even more recently, I stumbled across this article which discusses how the Georgia company that makes these fancy new “Freestyle” Coca-Cola machines uses landfill gas piped from a nearby landfill to generate almost 100% of the electricity and steam used to power the plant.  We’ve seen these new machines (which serve up to 100 different flavors) in various new fast food outlets and during a recent trip to Florida – who knew they were manufactured using renewable energy from waste?

Everybody Hates Garbage

1 Feb 2013

MDEQ has released its annual report on the sources and disposal of solid waste in Michigan. Solid waste is what most of us think of as garbage or trash (and not to be confused with “sanitary waste”) and includes industrial waste and demolition waste.

The 2012 report is interesting in that it shows: (1) a year-to-year decrease in waste disposed of in Michigan; (2) a slight increase in statewide disposal capacity to 28 years due to some landfill expansion permits issued; (3) roughly 22% of all waste landfilled in Michigan originated in 13 other states and Canada; (4) most of that waste was from Canada, despite efforts by Michigan’s Senators to stop all Canadian waste from entering Michigan.

Most interesting to me is that while the economy has certainly picked up over the last few years, the amount of waste being generated and landfilled (which usually tracks economic activity) has not.  Perhaps the last few years of business austerity have led to more efficiency at work and less waste at home.

Solid waste has been something of a hot topic in Michigan since the early 2000’s. In 2003, MDEQ studied shipments of waste into and originating in Michigan.  The study showed that less than 1/2% of all incoming waste contained any garbage prohibited from Michigan landfills and most of that originated in other states and not Canada.   In 2004, the Governor signed 11 bills into law, including these two, with the goal of trying to close Michigan’s borders to out-of-state waste. In 2005, the study was repeated and again, over 90% of all waste shipments had no offending contents.  Based on the most recent report, it appears that the legislative effort was, at best, partly successful as the percentage and amount of out-of-state waste dropped only slightly.

New FTC “Greenwashing” Guidance

4 Oct 2012

In 2010, I posted about greenwashing and the Federal Trade Commission’s  (FTC)  proposed response to it.  This week, the FTC  issued revisions to its “Green Guides” to help marketers ensure that their environmental claims are not deceptive.

FTC’s revisions include updates to the existing Guides, as well as new sections on carbon offsets, “green” certifications and seals, renewable energy and renewable materials claims.  The FTC modified and clarified the previous Guides and provided new guidance on environmental claims that were not common when the Guides were last reviewed.

The Guides warn against broad, unqualified claims that a product is “environmentally friendly” or “eco-friendly” and also:

• advise not to make unqualified claims about a product’s waste degradability unless they can prove that the entire product or package will completely break down and return to nature within one year after typical disposal – in particular the FTC took the position that items destined for landfills, incinerators, or recycling facilities will not degrade within a year; and

• clarified guidance on compostable, ozone, recyclable, recycled content, and source reduction claims. For example, just because something may be technically compostable, does not mean that it should be touted as such – if an average person cannot compost it with the rest of their compostables.

The Guides contain new sections on: (1) certifications and seals of approval; (2) carbon offsets, (3) “free-of” claims, (4) non-toxic claims, (5) “made with renewable energy” claims; and (6) “made with renewable materials” claims.

Certifications and seals may be considered endorsements covered by the FTC’s Endorsement Guides.  The FTC also cautions against using environmental certifications or seals that don’t clearly convey the basis for the certification.  The Guides don’t address use of “sustainable,” “natural,” and “organic.” Some organic claims are covered by the U.S. Department of Agriculture’s National Organic Program.

The FTC also released other resources to help explain the Guides, including a 4 page summary and a video.

It is more important than ever to be sure that you claims comply as the FTC has shown that it is willing to bring enforcement actions based on dicey or unsupportable environmental claims.

Composter update or anaerobic really stinks

2 Aug 2012

my composters

Experienced composters will tell you that having the right mix of materials (brown – leaves and green – food) is important as is making sure that the composter is turned to ensure that air is getting into the mix and that the compost doesn’t go anaerobic.  Why is this important?  Well, aerobic composting is typically faster and more complete and smells a lot less.

Well, both of our composters went anaerboic meaning that no one other than me would get anywhere near them – they smelled, well, like rotting food.   Plus there was a storm of fruit flies, making the whole process of adding waste food to the composters quite gross.

I decided to add some leaves and buy some compost “starter” and to turn the composters more frequently to see if I could get them back into an aerobic balance.  I’m pleased to tell you that the smell is largely gone as are the bugs.  It seems to have worked!  One of our two composters (the green one) is looking more and more like it is ready to be emptied.  I hope to report on that soon.

As you can see, the black one has highlighted something of a design flaw – when there’s a lot of liquid, it tends to run all over the composter’s “face” during turning.