Carbon dioxide of fossil fuels and deforestation have caused the atmospheric concentration of carbon dioxide to increase by about 43% since the beginning of the age of industrialization. Most carbon dioxide from human activities is released from burning coal and other fossil fuels. Other human activities, including deforestation, biomass burning, and cement production also produce carbon dioxide. Human activities emit about 29 billion tons of carbon dioxide per year, while volcanoes emit between 0.2 and 0.3 billion tons. Human activities have caused to increase above levels not seen in hundreds of thousands of years. Currently, about half of the carbon dioxide released
Natural-gas processing associated with or dissolved in crude oil. Natural gas production absent any association with crude oil is classified as “non-associated.” In 2009, 89 percent of U.S. wellhead production of natural gas was non-associated. Natural-gas processing plants purify raw natural gas by removing common contaminants such as water, carbon dioxide (CO) and hydrogen sulfide (HS). Some of the substances which contaminate natural gas have economic value and are further processed or sold. A fully operational plant delivers pipeline-quality dry natural gas that can be used as fuel by residential, commercial and industrial consumers. Raw natural gas comes primarily from any one