This renewable natural gas, essentially purified methane, is virtually identical to natural gas, but without the fracking.

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Depending on the economics of the location, the process can produce gas that can be burned for heat and power, or purified and sold as natural gas, or, perhaps in the future, used as a feedstock for chemicals or plastics.

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The startup also plans to use the money to develop products for processing wastewater and delivering purified water for industrial operations such as oil and gas or beverage production, Green said.

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The element to be purified is first incorporated into a chemical that can be turned into a gas. (In this case, the exact compound is still proprietary information.) Then an infra-red laser is shone through the gas.

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