Patents Assigned to Yellowstone Environmental Science, Inc.
  • Patent number: 5942117
    Abstract: An apparatus and method for anaerobic biodegradation, bioremediation or bioprocessing of hydrocarbons dissolved in an aqueous matrix, such as wastewater, groundwater, or slurry. Dissolved alkanes (saturated hydrocarbons), alkenes (unsaturated hydrocarbons), aromatic hydrocarbons and/or halogenated hydrocarbons are metabolized or cometabolized. In one form, the invention involves introducing an aqueous stream comprising at least one dissolved aromatic hydrocarbon (such as benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, phenol, o-cresol, m-cresol, or p-cresol) and a dissolved oxide of nitrogen ?such as nitrate (NO.sub.3.sup.-), nitrite (NO.sub.2.sup.-), nitric oxide (NO) and nitrous oxide (N.sub.2 O)!to a reactor, and operating said reactor under conditions that support denitrification of the aromatic hydrocarbon.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: August 24, 1999
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart, Tamara Darsow, Macgregor L. Fogelsong
  • Patent number: 5914441
    Abstract: A method and apparatus for anaerobic oxidation of metal sulfides in ores and concentrates. Base-metal and precious-metal ores and concentrates often contain metal sulfides, such iron sulfides (e.g., pyrite, pyrhotite, arsenopyrite, etc.), copper sulfides (e.g., chalcopyrite, chalcocite, etc.), zinc sulfides (e.g., sphalerite, etc.) and/or lead sulfides (e.g., galena, etc.) and/or other metal sulfides), that must be oxidized in order to recover metal values (e.g., gold, silver, or platinum group elements) from the ores. In the present invention, these metal sulfides are oxidized in one reactor under anaerobic or anoxic conditions using oxidized metal ions, such as ferrous ions (Fe.sup.+3), as the oxidizing agent. Anaerobic oxidation of elemental sulfur that is produced by metal sulfide oxidation is biocatalyzed by sulfur-oxidizing bacteria, such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans, or or Sulfolobus sp.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: June 22, 1999
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart
  • Patent number: 5672194
    Abstract: A method and apparatus for extraction of precious metals from their ores and the product thereof. Oxidized ore comprising a precious metal is exposed to a leaching solution (lixiviant) comprising a relatively high concentration (fugacity) of dissolved hydrogen sulfide gas, a relatively high concentration (activity) of bisulfide ions, and a relatively low concentration (fugacity) of dissolved hydrogen gas. The hydrogen sulfide gas and bisulfide ions are preferably added to the solution by sulfate-reducing bacteria growing in a medium comprising dissolved sulfate ions and dissolved nitrate ions, but abiotic sources may also be used. Examples of such bacteria include mesophilic, fresh-water species such as Desulfobacterium catecholicum DSM 3882 and Desulfovibrio simplex DSM 4141; mesophilic, salt-water species such as Desulfovibrio salexigens DSM 2638; and thermophilic, fresh-water species such as Desulfomaculum kuznetsovii VKM B-1805. The complexed precious metal is recovered from the lixiviant.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: September 30, 1997
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart, Tamara Darsow
  • Patent number: 5485518
    Abstract: A method and apparatus for electronic media program recognition and choice are disclosed. The invention allows parental control of the individual television programs (e.g., series, episodes, or individual music videos) and radio programs that can be viewed or listened to by young children. The invention can be practiced without the need for or reliance on a Government or industry-wide program rating system or a "V-chip" approach. The invention automatically locks out (blocks) all programs that have not been determined by the parent to be suitable for child viewing. Suitable programs are unlocked and viewable whenever they are broadcast. Means are provided for implementing two strategies for discrimination among TV programs. Signal processing means and signal recognition software are relied upon in situations wherein program identification information is not encoded in the composite television signal. Two approaches to signal recognition are provided: video signal (e.g.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: January 16, 1996
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart
  • Patent number: 5423226
    Abstract: A portable flow measurement system comprising a primary flow metering element and a secondary flow metering element is disclosed that will find application in metering irrigation water use, urban and rural storm water runoff, infiltration/inflow and wastewater flow rates. The primary element comprises a constriction in a closed conduit that produces pressures in the liquid flowing through it that are related to the rate of flow of the liquid. The constriction is preferably configured to cause essentially simultaneous filling of the constriction and the conduit upstream from it upon increasing flow rate and/or filling of the constriction and/or the upstream pipe before the modular limit is reached. The secondary element comprises a system for transmitting and sensing the pressures produced by the primary element, computing flow rates using the sensed pressure as a basis and storing the pressure data and/or the flow rate data.
    Type: Grant
    Filed: December 9, 1993
    Date of Patent: June 13, 1995
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart
  • Patent number: 5406828
    Abstract: This invention provides a method and apparatus for transmitting and sensing liquid pressure (head) and liquid level (depth) in flow metering, tide gauge and liquid salinity or slurry density measurement applications. The invention essentially eliminates the effect of pressure sensor temperature variations and the effect of long-term pressure sensor signal drift on pressure sensing accuracy by resetting the zero and gain of the pressure sensor prior to pressure measurement. A variety of sources of a known differential pressure may be used to reset the gain of the differential pressure sensor by simultaneously exposing both sides of the differential pressure sensor to the known differential pressure. In one embodiment of the invention, the head loss through exhaust port of a spring-biased comparitor is the known pressure differential used to reset the pressure sensor gain.
    Type: Grant
    Filed: November 16, 1993
    Date of Patent: April 18, 1995
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart
  • Patent number: 5351845
    Abstract: A generally cylindrical relative rotatable lock structure comprises three relatively rotatable coaxial members. The first and second members have generally opposed surfaces carrying connecting means which interengage to prevent relative axial movement between those members except in predetermined relatively rotatable positions. The third member is supported by one of the first or second members to prevent axial movement relative to the supporting member, but to permit rotatable movement. Friction between the third and non-supporting member causes the third member to rotate with the non-supporting member. The third member has connecting means cooperable with the connecting means on the member which does not support the third member to prevent relative axial movement between the third and non-supporting members except in predetermined relative position.
    Type: Grant
    Filed: January 31, 1992
    Date of Patent: October 4, 1994
    Assignee: Yellowstone Environmental Science, Inc.
    Inventor: Robert M. Hunter
  • Patent number: 5342769
    Abstract: A method for bioremediation of hazardous wastes is disclosed. The method can be used for anaerobic treatment of a liquid or slurry hazardous waste stream (e.g., industrial wastewater or sludge) or for treatment of contaminated groundwater. Removal of halogenated (e.g., chlorinated) hydrocarbons, such as tetrachloroethylene, trichloroethylene, 1,1,1-trichloroethane and similar xenobiotics is possible. The method involves biotransformation of (dehalogenation) halogenated hydrocarbons by means of natural methanogenic bacteria, Methanosarcina barkeri strain 227 and/or Methanosarcina vacuolata. These methanogens can accomplish cometabolism of chlorinated hydrocarbons during metabolism of a primary substrate such as hydrogen-carbon dioxide, methanol, methylamine, dimethylamine, trimethylamine and acetate. Reductive dechlorination, energy conservation and control of air pollution are accomplished.
    Type: Grant
    Filed: September 4, 1992
    Date of Patent: August 30, 1994
    Assignee: Yellowstone Environmental Science, Inc.
    Inventors: Robert M. Hunter, Frank M. Stewart