The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 24, 2005
Filed:
Jul. 02, 2002
Dennis J. O'rear, Petaluma, CA (US);
André Peter Steynberg, Vanderbijlpark, ZA;
Roger Van Gelder, Beaconsfield, GB;
Dennis J. O'Rear, Petaluma, CA (US);
André Peter Steynberg, Vanderbijlpark, ZA;
Roger Van Gelder, Beaconsfield, GB;
Chevron U.S.A. Inc., San Ramon, CA (US);
Abstract
Novel methods of providing fuels to a gas-to-liquids facility are disclosed. A gas-to-liquids facility typically operates in a remote location and therefore must supply its own energy needs. These facilities are often sustained by fuels having different heating values, and for smooth operation while transitioning from one fuel to another, (such as during startup, shut down, and emergencies) the Wobble Indices of the two fuels cannot greatly vary from one another. According to embodiments of the present invention, the Wobble Index of either or both of the fuels is adjusted such that their ratio is less than or equal to about 3. The fuel having the higher Wobble Index may be natural gas, and materials such as nitrogen, carbon dioxide and flue gas may be added to lower its Wobble Index. The fuel having the lower Wobble Index may be the tail gas of a Fischer-Tropsch synthesis, and materials such as methane, ethane, LPG, or natural gas may be added to raise its Wobble Index. Alternatively, carbon dioxide may be removed from the tail gas to raise its Wobble Index.