Patents Assigned to Zimpro Passavant Environmental Systems, Inc.
  • Patent number: 5262060
    Abstract: This is a process for wet oxidation of an ammonium salt containing waste liquor which prevents plugging of the vapor-carrying lines of the wet oxidation system. The vapor-carrying lines are maintained in an unobstructed condition by adding sufficient liquid water to dissolve condensed ammonium salt which can plug these lines. This provides for safe operation of the wet oxidation system.
    Type: Grant
    Filed: March 4, 1992
    Date of Patent: November 16, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Richard W. Lehmann, Bruce L. Brandenburg
  • Patent number: 5240619
    Abstract: A two-stage wet oxidation process for COD removal from high strength wastewater is disclosed. The wastewater stream is treated in a first stage subcritical wet oxidation zone at temperatures between about 250.degree. and 374.degree. C. to remove a substantial portion of the COD. Subsequently, all or a portion of the first stage oxidized waste stream is treated in a second stage supercritical wet oxidation zone at temperatures of 374.degree. to about 600.degree. C. to remove any remaining COD content. Both stages of wet oxidation treatment are carried out at essentially the same system pressure.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: August 31, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: William M. Copa, Richard W. Lehmann
  • Patent number: 5230810
    Abstract: A process for controlling corrosion in a wet oxidation system by controlling the operating pH range within the system is described. A pH operating range is selected within which corrosion to the wet oxidation system is minimized. The pH within the wet oxidation system is monitored and a pH adjusting material is added to the waste material being treated to maintain the system pH within the selected pH operating range, thus minimizing corrosion.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: July 27, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Mark A. Clark, David A. Beula
  • Patent number: 5192442
    Abstract: A process is described for the operation of a multiple zone batch treatment system for biological or biophysical treatment of wastewater. The system comprises two or more batch treatment zones with wastewater passing sequentially through all treatment zones. After the mix and settle batch steps occur for all zones, influent wastewater flows into the first zone and displaces clarified wastewater in a plug flow mode through each treatment zone and ultimately from the last zone. The combining of the decant and fill steps for all or most of the zones provides for shorter cycle times and greater capacity for the system.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: March 9, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: John Piccirillo, John A. Meidl
  • Patent number: 5183577
    Abstract: A process for treating an aqueous wastewater containing ammonium compounds. The process comprises the steps of preheating a liquid influent and introducing the preheated influent, an oxygen-containing gas an the wastewater into a reaction vessel for undergoing wet oxidation. An oxidized effluent is then withdrawn from the reaction vessel, which includes a gas phase containing ammonia and carbon dioxide and a liquid phase containing the ammonium compounds. The temperature of the effluent is then reduced to a temperature sufficient to condense a substantial portion of the ammonia into the liquid phase, and afterwards the remaining gas phase containing a substantial portion of the carbon dioxide is separated from the resulting liquid phase.
    Type: Grant
    Filed: January 6, 1992
    Date of Patent: February 2, 1993
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventor: Richard W. Lehmann
  • Patent number: 5089147
    Abstract: An improved apparatus and method for operating a granular medium filter is disclosed. The apparatus comprises an improved underdrain structure made up of a plurality of rectangular compartments which allows the filter bed to be "air pulsed" as well as backwashed for thorough cleaning of the bed. Nozzles are positioned within the rectangular compartments and directed vertically into the filter bed. Fluid from the nozzles helps to break up the bed during backwashing as well as countereact size classification of the medium during this process. The method of operating a filter with the improved underdrain structure is also described.
    Type: Grant
    Filed: May 1, 1991
    Date of Patent: February 18, 1992
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventor: David S. Ross
  • Patent number: 5084163
    Abstract: An improved apparatus and process for the operation of a down-flow granular medium bed filter is disclosed. A splash plate for dissipating the force of influent liquid is rotatably connected to support means, allowing the plate to rotate from a position parallel to the bed surface to a position perpendicular to the bed surface upon the liquid above the bed rising to a selected first level. The splash plate is maintained in the perpendicular position for the remainder of the filtration cycle, the backwash cycle and any chemical cleaning cycle, allowing unobstructed operation of the filter bed. The splash plate returns to the original position at the start of another filtration cycle.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: January 28, 1992
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Thomas L. Baumann, Ronald L. Edwards
  • Patent number: 5082571
    Abstract: A process for treatment of caustic sulfide liquor by wet oxidation in a nickel-based alloy system is described. The liquor is first analyzed for alkalinity consuming species and for nonsulfidic alkalinity. If excess alkalinity consuming species is present compared to nonsulfidic alkalinity, then additional nonsulfidic alkalinity is added to the raw liquor such that excess alkalinity is present during wet oxidation treatment, thus preventing excessive corrosion to the nickel-base alloy system.
    Type: Grant
    Filed: May 13, 1991
    Date of Patent: January 21, 1992
    Assignee: Zimpro Passavant Environmental Systems Inc.
    Inventors: David A. Beula, Joseph A. Momont, William M. Copa
  • Patent number: 5075015
    Abstract: A process for removing color and oxidizable organic matter from thermally conditioned sludge liquor is disclosed. The process comprises treating the liquor with 250 to 430 mg/l chlorine which removes 20 to 70 percent of the color and produces a chlorine residual in the liquor. The chlorine-treated liquor is mixed with a small volume of untreated thermal conditioning liquor to remove the chlorine residual, and the dechlorinated mixture is returned to the treatment plant influent for additional treatment.
    Type: Grant
    Filed: May 1, 1991
    Date of Patent: December 24, 1991
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventor: Robert J. Kamke
  • Patent number: 5057231
    Abstract: A method for starting up and controlling the temperature of a wet oxidation process in which a heat exchanger employing superheated steam is used to initially heat a waste stream introduced into a wet oxidation reaction vessel for start up and then to subsequently adjust the temperature of the waste stream, after it is preheated by the effluent from the reaction vessel, to a level suitable to maintain steady state operation of the reaction vessel.
    Type: Grant
    Filed: November 8, 1990
    Date of Patent: October 15, 1991
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Gene W. Mueller, Bruce L. Brandenburg
  • Patent number: 5018458
    Abstract: An improved method for controlling combustion zone temperature in a furnace independent of flue gas oxygen content is disclosed. The method comprises supplying a carrier gas containing a fine mist of liquid water droplets to the furnace combustion zone to control the maximum temperature within the combustion zone. The invention is applicable to both multiple hearth furnaces and fluidized bed furnaces, protecting the refractory furnace lining from damage.
    Type: Grant
    Filed: September 12, 1990
    Date of Patent: May 28, 1991
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Glover C. McIntyre, Robert J. Lacombe, Russell G. Forbess
  • Patent number: 5011114
    Abstract: An apparatus for controlling the blowdown slurry from a wet oxidation reactor is disclosed. The device includes a pressure control valve with a valve seat and support assembly which extends beyond the valve body to prevent erosion by the blowdown slurry. The apparatus also includes a displacement-compensating seal between the valve and receiving vessel to allow for thermal expansion and contraction during the blowdown cycle while maintaining the integrity of the seal.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: April 30, 1991
    Assignee: Zimpro Passavant Environmental Systems, Inc.
    Inventors: Kent T. Depuydt, Joseph S. Tikalsky