Patents by Inventor David Rakestraw

David Rakestraw has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20120103905
    Abstract: A microfiltration method and system for treating production water, for example, from oil and gas operations so that the treated water can be put to a beneficial user(s) such as agriculture, irrigation, industrial or municipal or potable applications. The production water is treated using a ceramic microfilter after pretreatment, for example, to remove volatile hydrocarbons and heavier oils, such as paraffins and asphaltenes, that could foul the ceramic filter. The effluent from the ceramic microfiltration can be further treated, for example, with activated charcoal or otherwise for the intended end use.
    Type: Application
    Filed: January 12, 2012
    Publication date: May 3, 2012
    Applicant: PRODUCED WATER DEVELOPMENT, LLC
    Inventor: David Rakestraw Stewart
  • Publication number: 20090204419
    Abstract: A method for generating new water with attached water rights comprising identifying a source of production water and treating the water in appropriate ways to provide water appropriate for beneficial use such as agriculture, irrigation, industrial or municipal or potable applications. Appropriate permits are obtained to create the new water with attached water rights.
    Type: Application
    Filed: April 9, 2009
    Publication date: August 13, 2009
    Applicant: Produced Water Development, LLC
    Inventor: David Rakestraw Stewart
  • Publication number: 20070183928
    Abstract: A chromatography system having continuously variable sources of fluid pressure and a controller to control the flow rates of one or more carrier fluids during an HPLC separation, the controller being responsive to the rate of analyte elution from a sample.
    Type: Application
    Filed: September 8, 2006
    Publication date: August 9, 2007
    Applicant: EKSIGENT TECHNOLOGIES, LLC
    Inventors: David Neyer, David Rakestraw, Christopher Bailey, Karen Hahnenberger
  • Publication number: 20050236314
    Abstract: A variable flow rate injector provides accurate, precise, and reproducible injection volumes that have low dispersion. The invention is particularly well-suited for HPLC injection volumes <500 nL but can be used to inject larger volumes and in different applications as well. Injections are performed at a first flow rate and separations are performed at a second flow rate. For improved HPLC system performance, the first flow rate is less than the second flow rate. The injector uses a variable flow rate fluid supply that allows rapid switching between flow rates desired for injection and flow rates desired for separations.
    Type: Application
    Filed: June 29, 2005
    Publication date: October 27, 2005
    Inventors: David Neyer, David Rakestraw, Jason Rehm
  • Patent number: 5545901
    Abstract: An apparatus and method are set for determining the centers of capillaries in a multicapillary electrophoresis array for subsequent rapid and efficient laser induced fluorescence interrogation. A galvometric scanner reflects the laser beam to scan the array during an alignment pre-scan. The beam interacts with the array to produce an intensity pattern indicative of the capillary centers. The scanner positions corresponding to the capillary centers determined during the pre-scan is recalled to direct the beam during the interrogation scan to the column centers.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: August 13, 1996
    Assignee: Beckman Instruments, Inc.
    Inventors: Stephen L. Pentoney, Jr., Clarence Y. Lew, David Rakestraw