Btu adjustment

Выражение встречается в следующем контексте:

Recovered vapors can generally be more valuable than methane alone, with a general Btu adjustment in excess of 2.0 per cubic foot.

Placing a dollar amount on those tank vapors using an average gas price of $9 an Mcf and a typical 2.5 Btu adjustment for tank vapors shows that U.S. procedures are losing almost $600 billion annually by failing to recover vapors.

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