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Coal is the most abundant usable fuel source on the planet Earth. We have enough mineable coal on Earth to last 3000 years; while natural gas will only last 200 years and oil even less (~ 100 to 150 years). Extraction of the coal mine methane (CMM) is important to keep the mine safe, capture wasted energy, and protect the environment. This is accomplished by drilling gob wells into the area of collapsing mine roof as the longwall mining machine proceeds forward, in-mine horizontal wells, and surface directional wells. Both the in-mine and surface directional wells are drilled into virgin coal seams and release a lot of coalbed methane that ultimately degasses the mine before operations begin. There are many good reasons to recover coalbed methane as listed in a table herein. A clear breakdown of the gas quality is shown in this chapter. Finally, the importance of wellhead dehydration is described and how it is accomplished.

Due to the various impurities in coalbed methane, such as H2O, CO2, N2, O2, and H2S, a gas processing/purification plant is required to bring the CBM gas to pipeline quality. Great care and intelligence must be used here, as wrong choices in processing the CBM gas can kill a project. CO2 rejection can be done with traditional amine systems, but new, advanced-technology membrane systems are much better for CBM. The importance of pretreat skids, when using membranes, is explained. N2 rejection can be even more challenging as it is the most expensive process due to cryogenic low temperatures for liquefying methane, but before doing so, all of the nonmethane impurities must be removed. This chapter includes a gas-processing application guide with easy-to-read tables showing how and when to use various processes along with their associated costs.

A clear understanding of the world's energy resources along with their economics and politics is necessary before selecting which CBM utilization best fits the project at hand. Global fossil fuel tables showing proven reserves are included for comparison. Fossil fuels thermal value table is also included along with their relationship and allows for easy comparability. US energy consumption and distribution are detailed in a graphic display. Also included is the “best use” for America's new-found source of abundant, over-produced natural gas (i.e., shale gas). Thermal dynamic efficiency is important and is critical to the decision making process of CBM utilization; keeping in mind that nothing beats direct heat for natural gas with thermal dynamic efficiencies of 90%–95%. A CBM utilization diagram is included to help guide decision making. In closing, a US energy source diagram is given with advice on its use based on science, not politics, as well as a look into the future.