Natural-gas processing at ambient conditions (i.e., pentane and heavier) are called "natural-gas condensate" (sometimes also called "natural gasoline" or simply "condensate"). Natural gas is called "sweet gas" when relatively free of hydrogen sulfide; gas that does contain hydrogen sulfide is called "sour gas". Natural gas, or any other gas mixture, containing significant quantities of hydrogen sulfide, carbon dioxide or similar acidic gases, is called "acid gas." Raw natural gas can also come from methane deposits in the pores of coal seams, and especially in a more concentrated state of adsorption onto the surface of the coal itself. Such gas is referred to
Piedmont Natural Gas Piedmont Natural Gas Piedmont Natural Gas Company, Inc. is a wholly owned subsidiary of Duke Energy. Piedmont is an energy services company whose principal business is the distribution of natural gas to over one million residential, commercial, industrial and power generation customers in portions of North Carolina, South Carolina and Tennessee, including customers served by municipalities who are their wholesale customers. They are invested in joint venture, energy-related businesses, including regulated interstate natural gas transportation and storage and regulated intrastate natural gas transportation businesses. In 2013, the company was awarded as a Platinum-level Start! Fit-Friendly Company by the American Heart