Energy Measurement Using On-line Chromatographs

摘要

Most natural gas custody transfer contracts today use MMBTU~2 rather than MCF as the accounting units of gas transfer. A BTU is the acronym for British Thermal Unit. One BTU is the quantity of heat required to raise the temperature of one pound of water from 58.5deg F to 59.5deg F (about 1055.056 joules (SI))~3. The higher the BTU value, the more energy can be obtained from burning the gas. It doesn't take as many cubic feet of gas to heat the hot water tank if the gas is 1090 BTU instead of 940 BTU per SCF. The BTU, then, is the mneasure of the actual amount of heat energy contained in a cubic foot (CF) of this natural gas. An MMBTU~2 is calculated by: BTU/CF * MMCF = MMBTU