Hydraulic fracking has grown to unimaginable hights in the past few years, growing by some 20% a year, and reaching a total market cap of $37 billion today. Recent tumbling prices for natural-gas have slightly detered exploration, but North America at least, which accounted for 87 percent of the fracking market last year, shows no sign of stopping. With so many fracking wells displaced all over the world, there’s a rather big concern over methane leaking. Primus Green Energy, a New Jersey company, aims to offer a solution to this problem by building pilot plants that syphon the leaking methane and turns it into valuable liquid fuel – gasoline.
One of fracking’s biggest problems has to do fugitive emissions: the natural gas that gets away from the wellhead or pipeline or is deliberately released or flared to the atmosphere because that is the simplest disposal solution for companies more interested in oil. In some oil fields, this practice has become so wide spread that flares can be seen all the way from the space, like the large swathes of the state of North Dakota, which in satellite images are as bright as Chicago. Burned or released into the atmosphere, the leaky methane can have important consequences on the environment.
photo: Primus Green Energy
The methane molecule is much larger than carbon dioxide and is roughly 21 times more potent than CO2 as a greenhouse gas. That’s to say that for every methane molecule in the atmosphere, the ammount of heat trapped by the methane is equivalent to the heat trapped by 21 Co2 molecules. So, while methane isn’t as abundant by far in the atmosphere as Co2, it still posses risks. Add the fact that methane leaks are hard to report and may actually be more widespread than previously believed. So, by all means, methane leaks shouldn’t be taken lightly.
Primus’ input to mitigate this issue is to stop wasting this otherwise valuable methane and turn it into liquid fuel. Synthetic fuel plants are from being a novelty. They’ve been around for a very long time, but a lot of them have been closed because the end product turned out to be more expensive than natural gas, the most recent closure being a plant in New Zealand belonging to Exxon. Primus officials state, however, that they have a more reliable and economically feasible method that operates with fewer steps than other synth fuel plants.
The methane is blasted with steam, cracking the molecule into hydrogen, and other smaller molecules made up of one atom each of carbon, oxygen and hydrogen. This resulting syngas is then fed into the first reactor where high heat and pressure, in the presence of a catalyst, turns it into methanol. This in turn flows into a new reactor where yet another catalyst shapes it into dimethyl ether, or DME. The DME can be used by itself as a fuel, but it’s not nearly as valuable as gasoline or diesel, so it goes through yet another refining process. In the third reactor, the DME is converted into various hydrocarbons that make up gasoline. The unfiltered gasoline goes through a final reaction cylinder that strips out undesirable molecules. Finally, a separator condenses the gasoline and circulates any spare methane molecules that happen to reach this final step back to the beginning to start the process anew.
This process is underway at one of Primus’ plants in New Jersey, at Hillsborough, and according to officials there, 70 percent of the methane molecules that flow onto the property end up as liquid fuel. Using the natural gas provided by the local utility, Primus transforms methane into valuable sulfur-free gasoline. And it’s just the kind of low-sulfur gasoline mandated by the U.S. Environmental Protection Agency on March 3, making it valuable as a blending component for companies that sell gasoline.
Primus wants, however, to reach the shale sites themselves. It’s unfeasible to stretch pipelines from shale drills to a plant many miles away, so the company hopes to one day have systems small enough to locate at oil or gas wells that would turn gases that would otherwise be wasted into 500 barrels a day of valuable chemicals or fuels, including diesel for the trucks that rumble up and down the oil fields.
Now, environmentally speaking this doesn’t help much. The methane converted into liquid fuel eventually gets burned, so carbon still reaches the atmosphere to trap heat and warm the planet. However, at least it doesn’t get in the atmosphere for nothing – it can be used as useful energy and help wean the U.S. off oil. Of course, there’s also a nifty profit to be had.
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