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:
Aug. 07, 2018
Filed:
Dec. 23, 2014
Schlumberger Technology Corporation, Sugar Land, TX (US);
Marcus Hofheins Donaldson, Somerville, MA (US);
Denise Freed, Newton Highlands, MA (US);
Martin Hurlimann, Newton, MA (US);
Yi-Qiao Song, Newton Center, MA (US);
Lalitha Venkataramanan, Lexington, MA (US);
SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US);
Abstract
Methods are provided for identifying one or more transition characteristics in a hydrocarbon fluid such as asphaltene onset pressure (AOP), bubble point or dew point. A transition characteristic is determined by subjecting the fluid to different pressures or temperatures, conducting NMR tests at the different pressures or temperatures to obtain signals, processing the signals to obtain values of a function of an NMR parameter as a function of pressure or temperature, and analyzing the values to find a discontinuity that identifies the transition characteristic. In embodiments, the NMR parameters may include at least one of a relaxation parameter such as Tor a T-Tratio, a diffusion parameter and an initial magnetization parameter. In embodiments, dual linear fitting, Bayesian change point detection algorithms, and instantaneous slope analysis may be utilized to analyze the values in order to find a discontinuity.