Stories tagged methane

Jan
05
2012

The future is now for some lucky Americans. The rest of us will have to wait and hope that someday soon our recycling trucks might also run on “trash gas.”

“Trash gas” is natural gas that is harvested from landfills where it is produced by the decomposition (breaking down) of organic waste. One future-thinking company, Waste Management Inc, now has over 1,000 trucks fueled by methane (a natural gas) that they collect from one of their very own California landfills.
I'd Rather be a Recycling Truck: A lucky 1000 Waste Management recycling trucks run on cleaner-burning natural gas (compared to conventional diesel).  Are more in the making?
I'd Rather be a Recycling Truck: A lucky 1000 Waste Management recycling trucks run on cleaner-burning natural gas (compared to conventional diesel). Are more in the making?Courtesy Tom Raftery

Natural gas can be used in vehicles in either a compressed or liquefied state. Waste Management’s trash gas trucks are about 50/50 compressed natural gas (CNG) and liquefied natural gas (LNG). You should check out those links, but to give you the gist of the idea here, imagine a balloon filled with natural gas. CGN is like squeezing that balloon. LGN is like cooling that balloon until the molecules inside condense into liquid like steam on a bathroom wall.

Why is this a BIG idea? CNG and LNG emit less carbon and nitrogen oxides into the atmosphere than diesel (the conventional fuel used by most large trucks). As you’ve probably heard, carbon dioxide is among the greenhouse gases contributing to global climate change. Meanwhile, nitrogen oxides contribute to smog, which is bad for your health besides being unsightly. Less is definitely more when it comes to carbon and nitrogen oxides.

As for more, Waste Management’s single currently operating LGN-generating landfill creates 13,000 gallons of LGN each day, which is enough to fuel 1,000 trucks. According to the primary source of this blog post, Waste Management has another landfill-turned-fuel station up for approval. With an additional 299 landfills and about 21,000 trucks, it might not be that long before a Waste Management “trash gas” truck comes rolling along your street.

Sep
19
2010

What happened to the missing ships and planes?


Bermuda triangle
Bermuda triangleCourtesy alphaios
Large amounts of frozen methane gas can be found under the ocean floors. When the BP oil drills hit a pocket of this gas it raced upwards, expanding ever larger as the pressure on it decreased. When it reaches the surface it really expands.

Methane bubbles can sink ships and snuff out airplane engines

Methane deposits occasionally erupt to the surface. A research paper published in the American Journal of Physics explains how large methane bubbles rising from the ocean floor might account for many, if not all, of the mysterious disappearances of ships and aircraft.

Oceanographic surveyors of the sea floor in the area of the Bermuda Triangle have discovered significant quantities of methane hydrates and older eruption sites.

Source

How Brilliant Computer Scientists Solved the Bermuda Triangle Mystery Salem News

Jul
13
2010

Brown gold!: This is actually the solid byproduct of a manure-to-methane operation. As you can see, it holds no fear for the owner of this bare hand.
Brown gold!: This is actually the solid byproduct of a manure-to-methane operation. As you can see, it holds no fear for the owner of this bare hand.Courtesy kqedquest
We’ve talked about the delights of cow feces before on Science Buzz, but mid-July always puts me in the mind of “brown gold” (coincidentally, the last occasion it came up was exactly four years ago today), and any time there’s talk of turning an animal into a fuel source, I get excited. (Remember that fuel cell that ran on the tears of lab monkeys? Like that.) Why not take another look?

So here you are: another wonderful story of cows trying their best to please us, before they make the ultimate gift of allowing their bodies to be processed into hamburgers and gelatin and cool jackets.

Poop jokes aside (j/k—that’s impossible), it is a pretty interesting story. The smell you detect coming from cattle farms is, of course, largely from the tens of thousands of gallons of poop the cattle produce every day. The decomposing feces release lots of stinky methane. (Or, to be more precise, the methane itself isn’t smelly. The bad smell comes from other chemicals, like methanethiol, produced by poop-eating bacteria along with the methane.)

Aside from being, you know, gross, all of that poop is pretty bad for the environment. The methane is released into the atmosphere, where it traps heat and contributes to global warming (methane is 20 to 50 times more potent than carbon dioxide as a greenhouse gas), and the poop itself is spread onto fields as fertilizer. Re-using the poop as fertilizer is mostly a good idea, but not all of it gets absorbed into the soil, and lots of it ends up getting washed away into rivers, lakes, and streams, where it pollutes the water.

Some farms have managed to address all of these problems, and make money while doing it.

Instead of spreading the manure onto fields right away, the farms funnel all the poop into swimming pool-sized holding tanks, where it is mixed around and just sort of stewed for a few weeks. All of the methane gas produced by bacteria as it breaks down the manure is captured in tanks. What’s left is a fluffy, more or less sterile, solid that can be used as bedding for the animals, or mixed in with soil, and a liquid fertilizer that can be spread onto fields.

The methane can then be used on-site to generate electricity, either by burning it in a generator, or using it in a fuel cell. (The methane is broken apart and combined with oxygen from the air to produce electricity, water, and carbon dioxide.) A large farm will produce enough electricity to power itself and several hundred other houses. (The extra electricity is just put back into the power grid and sold to the power company.)

Whether the methane is burned or used in a fuel cell, the process still creates carbon dioxide. However, CO2 isn’t nearly as bad as methane when it comes to trapping heat, and because the original source of the carbon was from plant-based feed, the process can be considered “carbon-neutral.” (Although one might argue that the fossil fuels involved in other steps of the cattle farming process could offset this. But let’s leave that be for now. It’s complicated.)

The downside is that setting up an operation to capture and process manure, and to generate power by burning it is expensive—it took about 2.2 million dollars to do it at the farm covered in the article, with about a third of that coming from grants. Still, the byproducts (electricity, fertilizer, soil/bedding) are profitable enough that the system could pay for itself over the course of a few years.

It’s amazing, eh? Out of a cow’s butt we get soft, clean bedding, liquid fertilizer, and electricity, all without the bad smell. What a world.

Mar
20
2010

Dino killer
Dino killerCourtesy Donald Davis (for NASA)

How Earth impact kills dinos

As "mdr" explained recently in, astroid found guilty of killing dinosaurs that a panel of scientists, after reviewing all evidence, blame an asteroid impact for the demise of the dinosaurs.

Ozone killed the dinosaurs

A paper has just been published saying that dinosaurs choked on ozone.

A new study in the journal Paleogeography, Paleoclimatology, Paleoecology puts forth the idea that the Chicxulub impact, long blamed for the extinction of the dinosaurs at the end of the Cretaceous era 65 million years ago, could have done them in by flinging huge amounts of ozone precursor chemicals -- nitrogen oxides, methane, and other hydrocarbons -- into the air.

Below the article in Discovery News, this comment by 1sang (Doug) explains why mammals and avians survived.

In order to (survive) all you'd have to do is get on steeper slopes and find enough food to live for a couple of years. Mammals and smaller avian dinosaurs could more easily accomplish this than their massive cousins (in fact, many were probably already in this safety zone away from the many large predators roaming the lowlands).

He also notes that methane release leads to an increase in ozone and that today we have the beginnings of lots of methane being released (I wrote about this here: Methane ice).

Jul
23
2009

Much truth is spoken in jest.
Much truth is spoken in jest.Courtesy Meredith P.

We've all heard about global warming, the undeniable fact that the Earth's temperatures rose (dramatically / sharply / noticeably – take your pick) from 1980 to 1998. (We've heard considerably less about the equally undeniable fact that from 1999 to present temperatures have held steady or even dropped, but never mind.)

We've all heard that carbon dioxide, released into the atmosphere when we burn coal, gas or other fossil fuels, is the (only / primary / most important) source of the warming. (The Earth also warmed during Roman and Medieval times, when fossil fuel consumption was vanishingly small. But never mind.)

And we've all heard how this warming is going to bring about floods, drought, storms, extinctions and other ecological disasters if we don't reduce out carbon output by (the end of the century / 2020 / tomorrow afternoon).

Those first two points can be tested through observation and experiment. The last one cannot. It's a prediction about the future, and you cannot observe something that hasn't happened yet. But you can always bolster your position by accurately predicting the past.

Now, that may seem like a waste of time – I mean, it's the past. We know what happened. But that's what makes it such a great laboratory. Y'see, scientific predictions are based on models. Scientists take all those observations and experiments, put them in a computer, and see where the trends lead. You can test the model by taking observations from some point in the past, crunching the numbers, and seeing if the results match what we know happened next.

And that's exactly what Richard Zeebe, James Zachos and Gerald Dickens did. In an online article published by the journal Nature Geoscience, these three scientists took the model used by climate researchers to predict future global warming and applied it to an episode of past global warming. Specifically, they looked at a well-studied period 55 million years ago when the Earth's temperature rose dramatically. They plugged the data from that warming into the model used to predict current warming, and they found....

It didn't work. The climate models being used today were unable to duplicate known conditions from the past. They weren't even close – the results were off by about 50%.

Emily Latella, call your office.

Sep
12
2008

A mighty duke: and very powerful, although not a favorite at parties.
A mighty duke: and very powerful, although not a favorite at parties.Courtesy Albedo-ukr
San Antonio has made a deal with the duke. A particularly mighty duke, too, and one that has often been overlooked, despite this duke’s ability to deliver great power.

Aug
13
2008

How convenient!: Jumpmeat, with a little pouch to hold more jumpmeat!
How convenient!: Jumpmeat, with a little pouch to hold more jumpmeat!Courtesy .robbie
Y’all got kangaroo knives, right?

What? You don’t have kangaroo knives? Well… I mean… what… How do you cut your kangaroos up, then?! This is madness! Cats and dogs, living together! Ewok Adventure! Sour candy! Madness!

I think there must be some kind of misunderstanding. A kangaroo knife isn’t necessarily like a big Crocodile Dundee knife* (although, that is a really nice kangaroo knife). No, pretty much any sharpish object can be a kangaroo knife. So, yes, a knife can be a kangaroo knife, but what else? A chipped rock? Yes, what else? Sure, a jagged piece of scrap metal would make a nice one. Anything else? A sharpened spoon? Very good, yes, a sharpened spoon could work. A fingernail? Well, I suppose it depends on the finger and the nail, but maybe.

I think you’re getting the idea. But why do we need all of these kangaroo knives in the first place? To be honest, it’s probably only the Australian Buzzketeers out there (maybe?) that would have any use for them, but it doesn’t hurt for the rest of us to be prepared. See, a recent article in the journal Conservation Letters recommends that expanding the kangaroo industry in Australia, and shrinking the cattle and sheep industries, would significantly cut the continent’s greenhouse gas emissions. Specifically, growing the kangaroo population to 175 million by 2020 (and reducing the cattle and sheep populations proportionately) would eliminate 16 megatons of greenhouse gas, or 3 percent of Australia’s total emissions.

It’s not just any old greenhouse gas that would be cut, either—we’re talking about methane, one of the stinkiest, hottest, greenhousiest greenhouse gases of them all. Ruminants—animals that chew cud and have multi-chambered stomachs, like cows and sheep—produce a lot of methane, up to 60 percent of global methane emissions†. A dairy cow can produce about 50 gallons of methane gas a day! Kangaroos, on the other hand, produce only about one third of the methane of a ruminant animal does. And, as a little environmental bonus, kangaroos’ large, padded paws are much easier on the land than the hooves of ruminants, and contribute less to erosion.

But what are we supposed to do with all these millions of kangaroos? Eat them, naturally. (This is where the kangaroo knives come in!) Kangaroo meat is reportedly high in protein, low in fat, and it has high concentrations of conjugated linoleic acid (a chemical that seems to have anti-cancer properties, and tends to reduce body fat in humans). But, you know, it’s kangaroo meat, which some people may have a problem with**.

It’s difficult to say, too, what the other environmental ramifications of increasing one animal’s population dozens of times over might be. Maybe the kangaroos could be trained to eat rabbits, or something.

Assuming y’all had some kangaroo knives, do you think you could deal with eating kangaroo? You know, for nature?

*Doesn’t Paul Hogan look like he’s about to do something just awful to Manhattan there?

†The EPA’s website says that ruminants only account for 28% of global methane emissions. But that’ still a lot.

**The kangaroo meat industry actually held a competition to come up with a new name for the meat that didn’t conjure up images of doe-eyes and fuzzy little faces. The finalists included kangarly, maroo, krou, maleen, kuja, roujoe, rooviande, jurru, ozru, marsu, kangasaurus, marsupan, jumpmeat, and MOM (meat of marsupials), but the winning name ended up being “australus.” Australus was for sure not the best name. The best name was “jumpmeat.”

As Midwest flooding and rising demand for ethanol pushes the price of corn ever higher, Cornell researcher Norman Uphoff is developing a new way to grow rice. His method produces more grain to feed more people; uses less water; and releases less greenhouse gas into the atmosphere.

Jun
08
2008

The face of the enemy: Know it well.  They wait, biding their time, building up the strength of their numbers, and of their horrible, secret weapon of doom!
The face of the enemy: Know it well. They wait, biding their time, building up the strength of their numbers, and of their horrible, secret weapon of doom!Courtesy foxypar4

That’s sheep farts to you and me, and apparently it’s a major problem. There are over one billion sheep in the world. They spend their day, standing in the meadow, gamboling playfully, watching Sam, the big shaggy cartoon sheep dog, foil the ingenious but inevitably futile efforts of Ralph, the wolf who looks suspiciously like a coyote.

And eating. Grass is what sheep eat. Unfortunately, they can’t digest it. Instead, they have little tiny microbes in their stomachs (four stomachs per sheep) that break down the plant fiber for them.

Unfortunately, microbes are rude little creatures, emitting methane gas with every mouthful and nary an “excuse me” to be heard. The methane builds up inside the ovine until it escapes in the form of sheep farts. (And, seriously, if you ever have a chance to write an essay that can justifiably include the phrase “sheep farts,” then you should seize the opportunity and use the term just as often as you possibly can.)

Anyway, the methane (a.k.a. sheep farts) gets into the atmosphere where, some would have it, it will trap heat and warm the globe and eventually destroy civilization as we know it. This may or may not be a bad thing, but I personally would hate to see my home destroyed just because of sheep farts.

Fortunately some researchers in New Zealand have come to our rescue. These plucky kiwis are tackling the sheep fart menace head-on, trying to develop a vaccination that will improve the microbes’ table manners. An anxious world holds its breath – partly in anticipation of the coming breakthrough in sheep fart technology, but mostly in response to the sheep farts themselves.

Dec
18
2007

Burning methane hydrate
Burning methane hydrateCourtesy United States Geological Survey

What is Methane ice?

Huge amounts of methane are being found on the ocean floor, trapped within cages of water molecules.

Methane clathrate, also called methane hydrate or methane ice, is a solid form of water that contains a large amount of methane within its crystal structure (a clathrate hydrate). wikipedia

Geologists estimate that significantly more hydrocarbons are bound in the form of methane hydrate than in all known reserves of coal, natural gas and oil combined. India and China plan to spend hundreds of millions of dollars learning how to tap into this huge reservoir of energy (Spiegel online).

Carbon curse or cure

Relying on this carbon based energy instead of renewable energy sources could worsen global warming by releasing more greenhouse gases. To be carbon neutral the carbon dioxide from burning carbon fuels needs to be captured and sequestered (locked up). Harvesting methane ice offers just this opportunity.

When a certain amount of pressure is applied to the cage-like crystal structure, carbon dioxide can penetrate the layer of ice, at which point it displaces the methane. Then a new cage of frozen water molecules forms around the carbon dioxide. Klaus Wallmann, Uni Kiel

Wallman is also impressed by the ratio at which the gases are exchanged. For each dissolved molecule of methane released, up to five molecules of carbon dioxide disappear into the ice cage. Wallmann hopes to see, in the not-too-distant future, tankers filled with CO2 heading out to sea to pump their climate-damaging cargo into the depths.

You might also read about research being done at Columbia University, "Carbon Neutral Methane Production Via Hydrates".