Saturday, May 26, 2018
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Garbage Needed
Walter Salm, Editor

Last month, we talked about a plethora of discarded CRTs from old computers and TV sets. Unfortunately, there did not appear to be a reasonable answer to this dilemma. Now we're looking at another trash category but with a very different kind of back story: ordinary household garbage.\par \There's been an interesting ecological shift in recent years that involves converting garbage into electrical energy. There are two ways to do this: burn the garbage in an incinerator that heats water to run a steam turbine. Or there's the more ecologically acceptable practice of amassing garbage piles that decompose, feeding armies of bacteria, which release huge amounts of methane, which in turn can be reclaimed to produce electricity. The methane can be burned to produce steam, it can fuel internal-combustion engines to turn generators, or it can be piped directly into a fuel cell stack that will strip the hydrogen atoms and combine them with oxygen atoms to produce electricity, along with water vapor as a waste product.

There are a couple of problems with the fuel cell versions of this type: first, there are no readily commercially available hi-temp fuel cells. These fuel cells also produce a waste byproduct of carbon dioxide, which we already have in super abundance, and there's the high cost of purchasing and implementing the system, when they are in production. But this is followed by a huge payback in free, mostly green energy. And the carbon footprint is very small indeed, and can often be handled by planting a few trees nearby. But for now, feeding the methane to internal combustion engines that run electric generators is a highly favored solution in many parts of the world.

The garbage-to-electricity formula is nowhere more appreciated than in Scandinavia, where numerous conversion plants are currently operating, but with a strange side effect: they're running out of garbage to burn! In fact the city of Stockholm has been advertising wherever there's a "garbage wanted" category, and have managed to glean a few barge loads from the U.K. But not nearly enough. Most of the British want to burn their own trash. Some trash comes from Germany, but much of this is sidetracked to burn sites in Denmark. Now Italy has entered the equation, with its willingness to export large amounts of garbage to Scandinavia.

Barges full of garbage are not a new idea; such a barge originated in Islip, Long Island (NY) in 1987, when local landfills had been filled to capacity. A barge loaded with 3168 tons of garbage was sent on a fruitless voyage, first to Morehead City, North Carolina where it was expected to be deposited in a landfill so it could be mined for its methane gas. But before it could be unloaded, local news media in North Carolina got hold of the story, playing it up in such a way that the local politicians ordered the barge to leave and take its garbage with it. Next the barge tried Mexico, but was warned away from that country's coast, so it went from there to Belize, where it was also refused and was forced to turn around and head back to Long Island. Eventually, its load was burned in a Brooklyn, NY incinerator and the ashes returned to Islip, where the garbage barge had started its journey. There was a lot of fuel burned on that tugboat that provided the barge's motive power. But that boondoggle is history, and illuminates there has been a huge shift in public opinion since then.

Today, as more and more municipalities in the U.S. start to get with the program, more garbage will become energy instead of permanent landfill. It's really a win-win situation, especially since it's so difficult to obtain the needed land, permits and funding for conventional landfills. Because of today's emphasis on recycling, garbage is now largely free of metal cans and plastic containers, making it easier and safer to burn.

When I was in the US Army during the Korean War, such garbage went into large metal garbage pails labeled "Edible" and was used to feed pigs, which in turn were slaughtered to became food for the mess halls. Naturally, there were half-serious jokes about the Edible Garbage being recycled directly through the mess hall and becoming the next day's mystery meal; army food was not held in very high esteem by those who had to eat it. Other containers were for cans and bottles. The military was the first organization I can recall that did its own recycling. It also fell upon some hapless souls (sometimes including me) to scrub out those "Edible" garbage pails with "hot sudsy water"; they were big and they were dirty. This was the era before dumpsters became popular.

The burning in incinerators and/or the decomposition into methane includes not only "edible" garbage, but also papers and wrappers. And that burning will be used to generate electricity, a commodity that has become increasingly precious as energy and fossil fuel prices continue to escalate. Today's society uses more and more energy, and apparently is producing a declining amount of "edible" or otherwise usable garbage. But it is good to know that this garbage will no longer go to waste. Today's garbage is tomorrow's electricity.  

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