Tag Archives: landfill

A Stinky Subject

This isn’t about sex, murder, war, politics, or Donald Trump, so if that’s all that interests you, you may as well stop reading now.  It’s about landfill gas recapture and utilization, a subject that makes my engineering friends yawn but fascinates me.

It links my interests in environmental toxins, garbage disposal, and multi-purpose innovation to address commonly acknowledged problems.  While the political scientists debate whether the Earth is undergoing “climate change” and, if so, whether humankind is causing it, I’m looking at litter in the streets; noting the extraordinary growth of plastic and single use packaging; and throwing away heaps of junk mail in post office recycling bins.  At least the PO has recycling bins, a forward shift in consciousness, according to me, within the past ten years.  Not only does the post office subsidize this mountain of murdered trees by reduced rates, but my various alma maters and professional organizations are the worst perpetrators of this global plot to deforest the planet and speed up the global warming agenda.  One would think the ivory-tower elitists would be the first to rail against this glut of self-serving propaganda, but alas, they can’t afford to support their tenured positions and building campaigns with mere tuitions.  They must perpetually dun their graduates—and their graduates’ offspring—for money, if only to prove how cost-ineffective and eco-unfriendly they are.

So, rather than spend money supporting those who can’t support themselves, I choose to educate myself without cost in ways to reduce all my problems and the world’s problems at the same time.  A tall order, perhaps, and maybe a futile one, considering the stinky subject of landfill.  Nobody wants to touch it, unless, of course they can get government funding.

To get government funding, one is obliged to package the idea in terms that make the government look good.  For instance, did you know the United States has 2000 regulated landfills, the most in the world?  By 2006, the US generated 413 million tons of municipal solid waste, and 64% went into landfill.  70 percent of this was composed of food, paper, and corrugated cardboard, and 15 percent was of petrochemicals, mostly plastic.

Biogas, including carbon dioxide and methane, are emitted from decomposition of organic materials in landfill.  Aerobic decomposition of waste generally leads to the production of carbon dioxide (CO2), and anaerobic decomposition produces methane (CH4). Methane is also known as natural gas. MSW (municipal solid waste) landfill gas is comprised of 45-60% methane and 40-60% CO2.

Methane is believed to be at least 24 times more potent than carbon dioxide in its global warming effects.  About 50 million tons of methane are generated annually by municipal solid waste, but only 5 million tons are captured.

Landfills generate a maximum of methane at five years, then the amount begins to decline.  Landfill gas utilization is a process by which methane is captured and used to generate electricity or heat, or upgraded for inclusion in commercial natural gas products.  In 2006, there were 325 landfills in the US that collected biogas, up from 231 in 1999.  California had the most:  65 landfill gas facilities, followed by Illinois, Michigan, New York, and Pennsylvania.  In 2001, there were 955 landfills that recovered biogas, with the most in the United States, followed by Germany and the United Kingdom.  In the United Kingdom, the number of facilities went from 329 in 2005 to 519 in 2009.

There are two methods for capture of methane from landfill, closed and open capture.  Closed capture refers to gas extraction from landfills that have been closed and can be capped.  It is considered more efficient than capture from open landfills, at 84% and 67% respectively.  Methods for capture including drilling wells either vertically or horizontally.  Equipment needed for utilization depends on the size of the landfill.  Smaller facilities can employ reciprocating engines; medium-sized facilities can use turbines; and steam cycles are used for the largest deposits.

General Motors has significantly reduced its energy costs by using landfill gas to power some of its production facilities.  As of August, 2016, the General Motors Orion plant in the Orion Township of Michigan boasted that landfill gas was supplying 54% of its electricity.  The gas comes from two open landfills nearby, owned by Waste Management and Republic Services, respectively.  The GM plant also has a 350 kW solar array.

There are incentives from the Treasury Department, Department of Energy, the Agriculture Department, and the Department of Commerce for landfill gas extraction.  Landfill gas is considered a renewable form of energy.  The US EPA operates a landfill Methane Outreach Program.

Opponents of landfill gas utilization include such organizations as the Energy Justice Network, which claims that landfill gas has contaminants that are either inherently toxic or combine into toxic substances when burned.  Although “non-methane organic compounds” (NMOCs) comprise less than one percent of landfill gas, there are also non-organic toxic substances, such as mercury and tritium, in minute amounts.  Also, when halogens–like chlorine, fluorine, and bromine– are combusted with hydrocarbons, they can produce dioxins and furans, some of the most toxic substances known.  While other sources state that a burning temperature of 850 degrees centigrade can destroy dioxins, Energy Justice Network claims these can be re-formed in the cooling process.

At the same time, Energy Justice Network admits that methane is responsible for 10.6 percent of global warming from US human sources, with 35.8 percent of this from landfill gas.  It also claims that if landfill gas is to be utilized for energy, boilers offer the safest mode, with turbines, then internal combustion engines less desirable.

 

 

 

 

 

 

 

 

 

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The View from Below

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I shoveled the dock steps the other day.  This was part of my latest health initiative, with the purpose of swimming in the river.

Now, most people don’t have a dock or concrete steps to a polluted river where they can swim.  Most people haven’t grown up on said river and watched it change gradually over the past 60 or so years.  It is a blessing and a curse.

While doing this mundane labor, which with clean-up took about two hours, I had time to ponder many worldwide concerns.  First, I listened to the constant buzz of helicopters at Hunter Army Airfield, only a couple of miles–as the helicopter flies–from my house.  There were also military aircraft flying overhead, as I live only 28 degrees off Hunter’s flight paths, and those planes fly low, low, low over my head. This reminded me that the US is engaged in perpetual wars, and I live in a war zone, what with the strong military presence loud, clear, and constant.

Next, I thought about the Clean Water Act of 1972, when the Army Corps of Engineers got jurisdiction over all “wetlands” including the “hydrophytic” marsh that surrounds my small spit of land.  I wondered if the AC of E would fine me for taking mud off the steps and depositing it in the center of my land, which is mine but not mine in that I pay property taxes but can’t modify it.  This spit of land has been sliding into the river for years and now becomes flooded in spring and fall tides.  The channels in the area are also filling in, because no one dredges them anymore, even though the drainage ditches are perpetually clogged and contribute to frequent, severe flooding in Savannah.

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The local movers and shakers would prefer to dump poisonous malathion by helicopter on the entire ecosystem than drain the bogs where mosquitoes breed. That the Army Corps of Engineers pays Chatham County to control mosquitoes, yet operates the largest mosquito habitat in two states does not seem important to anyone but me.  That the dredge material from current harbor deepening project will increase the mosquito habitat at this international port presents no red flags to those who are developing vaccines for mosquito-borne disease but are blithely nonchalant about the cushy habitat they are creating.

This brings me home to the polluted river, which still has fish and shrimp, but not as many as in my childhood.  I figure if fish can swim in it, so can I.  I’ve been stomping around, crabbing, shrimping, boating, water skiing, and swimming in that water since I can remember, so know it well.  While shoveling, I thought about “climate change,” and the claim that the oceans are rising.  I also remembered reading about how land is washing into the oceans and wondered if the oceanic rise is relative to the land’s sinking, in a leveling out that would lead to the oceans’ getting shallower. Shallow water heats more quickly than deep water, as any swimmer knows, and holds more heat, so this could explain some of the climatic changes.

So then I thought about President Trump’s withdrawal from the Paris Accord and wondered whether it makes any difference in the long run.  I’ve never been a fan of government solutions to government-supported problems, like the fact that deforestation is a major contributor to climate change.  I don’t believe in paying corporations not to cut trees (as in “carbon credits”) and would prefer instead to reduce demand for paper, like junk mail and single-use packaging.  International Paper, the owner of primo rain forest in South America, and a huge polluter of the Savannah River and air, does not recycle paper.

That got me to thinking about the enormous amount of methane produced by the marsh, the fact that methane and natural gas are the same thing, and that Germany is the world’s leader in recycling (70%).  In addition, Germany has to import garbage to fuel its waste-to-energy plants that provide so much of its heat and electricity. There is also new technology to capture methane produced by landfill, but the US lags behind places like China in its adoption of these promising technologies.  No wonder Angela Merkel was frustrated by Trump’s withdrawal from the Paris Accord. Germany is the world leader in sustainability, and should be so acknowledged.

So, Donald Trump may believe coal gives the US a financial advantage, but this is short-sighted.  Apparently China is the largest purchaser of US coal exports, but China built 431 waste-to-energy plants in 2016, so it may not need our coal much longer.  With the reduced cost of solar, India is also going greener.  China is the biggest carbon-emission nation in the world, and the US is second.  Russia is third, and India fourth, according to Google 2011 data.  Americans probably generate the most waste, though, 4.5 pounds of garbage per person per day, and recycling has decreased, now down to about 30 percent.

So, while I solved my personal problem of how to swim without getting mud between my toes and oyster shell cuts on my feet, I also solved a lot of world problems, and I never had to leave home.