The firm also owns 21 gas processing plants that separate propane and ethane from raw natural gas.

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Natural gas processing means the separation of non-methane gases from raw natural gas, or the separation of the non-methane gases and liquids into one or more components.

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But with a global capacity glut in 2001 chemical prices softened, even as raw material costs like natural gas began a fivefold price increase.

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Natural gas prices, electricity prices, raw material prices, project financing costs and availability, emerging technologies and, hardest of all, politicians, who can make or break the industry with their decisions on government subsidies.

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On the West coast, Perth lies at the center of its vast natural gas and iron ore fields that are supplying China with much of the raw material for its factories.

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But with emerging technologies, raw biogas can be stripped of carbon dioxide and other trace gases, bringing it up to the quality level of natural gas.

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