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## Things I Learned in My Chemistry Course Today

I’ve been poking around chemistry books for fun lately. I learned today that when you burn CH4 (i.e. methane, the stuff that comes out of fracked wells) you emit the much despised CO2 (we knew this, it just happens to produce a lot less per BTU than oil and coal) but it also emits a lot of water.

So here is my question to the fractivists, who are the paragons of science: comparing the 5+ million gallons of fresh water that are used to frack each well here on the East Coast (assuming none of it gets recycled or reused or treated, which of course is not true) to how much gas is produced in each well (here is a cool fact – imagine saying the same thing about a solar panel or windmill?), how much clean water is produced as a combustion byproduct from each fracked well as all of its natural gas is used?

Anyone want to bet what the answer looks like? My sense is that the silence on this speaks volumes. And I’ll send a brew to whomever actually does such a calculation with some confidence.

### 8 Responses to “Things I Learned in My Chemistry Course Today”

1. ZT says:

I simply can’t find an estimate for exactly how much water it takes to get a unit of methane, or even exactly how much annual production comes from fracked wells, but a reasonable assumption seems to be 50%. Wolfram Alpha says the US produces 23 trillion ft^3 a year (as of 2011). That’s 2.71×10^13 moles of methane, giving us 4*2.71×10^13 moles of H2O. That’s 1,950,000,000,000 KG, or 515,984,000,000 (516 BILLION) gallons of water. Divided in half, that’s still 258 billion gallons from the fracked methane specifically.

Caveats: The amount of water used per well is highly variable (depends on the terrain, direction of drilling, and number of times a well is fracked), the output per fracked well here is an estimate, and I didn’t take into account recycled fracked water (which is about 20% of it). But none of these should set off the calculation by multiple orders of magnitude…

Also consider that some of the water is going to end up as water vapor (itself a greenhouse gas), and that some natural gas use will displace other water-producing combustion.

Were you serious about the brew?

• wintercow20 says:

So, this calculation tells us that if we frack about 50,000 wells, then (using the language of “E”nvironmentalists) fracking would be “water neutral?” Yes WV is a GHG, but if suspended as cloud cover it’s not clear what the net effect is.

Yes, a brew. Stop by one day and I’ll deliver it to you.

• ZT says:

Apparently so. The other thing to consider, of course, is that the real resource we care about is clean water, not water, so any fracking that uses wastewater, seawater, or some other source would be even more “water-positive.”

That’s awesome; I’ll set up an advising appointment after break.

2. Harry says:

This problem is easier to solve than you think, now that scientific notation is a staple for understanding ten -year federal anything. You have just to know what mole of water weighs. True chemical engineers can do this with a slide rule. I can do it, but it would probably take me a whole day.

Sulfur dioxide is a pollutant. You learn this in high school, that SO2 combines with water to produce sulfuric acid. Carbon Dioxide is not a pollutant. You ingest it with your grape soda, and the plant kingdom depends on it. Plants breathe it in, and exhale oxygen and water. Without the plant kingdom (broccoli) we would not have the animal kingdom.

Carbon dioxide is roughly 0.004 percent of the atmosphere. I am not sure how this generally accepted factoid is measured, but I have a hard time imagining how if that concentration were doubled whether its effect would not be dwarfed by clouds, solar flares, etc. We would not be here if there were no atmosphere, providing its beneficial effect. To raise such a question puts one subject to the modern-day Spanish Inquisition.

• Greg W says:

Not to be contentious, but a lot of scientific facts are “hard to imagine” but nonetheless true.

For instance, it’s hard to imagine that ingesting less than a microgram of polonium would kill you. A pinhead is about a cubic millimeter in size; that lethal dose of polonium is four orders of magnitude smaller (I calculated ~.0001 cubic millimeters).

I have no idea whether you’re right, but I don’t think instinct can apply broadly to a system you need a graduate degree to understand and a computer to model.

• Harry says:

Greg, it is easy to imagine how a small amount of something radioactive can kill you. It is also easy to imagine how more CO2 in the atmosphere might have AN effect.

However, I do not think you have to have a graduate degree in physics to qualify to discuss the subject. I would defer to the quantum physicists, assuming they do their science in a disinterested fashion, on how certain wavelengths of radiation are let into our atmosphere, and how other radiation is trapped, similar to a greenhouse. I’ve read all that.

Any good scientific theory has to have a mechanism that, when talking of earthly matters, is based on Newtonian physics and modern chemical principles, not some goofy idea.

• Harry says:

Rizzo’s point was about on the silence when we raise honest questions. Was not this the same political problem Galileo faced?

3. Harry says:

Way to go, ZT. You earned your brew.