Patents Assigned to Envirotech Corporation
  • Patent number: 5227136
    Abstract: A reactor vessel for use in treating slurries containing minerals, soils or sludges contaminated with toxic organic substances is disclosed. The vessel includes a tank, having a sealed cover, a mixer arrangement, an air supply arrangement and an exhaust gas recycling system. The air supply arrangement includes one or more porous, flexible membrane diffusers adapted for introducing gas, in the form of fine bubbles, into a tank-contained slurry.
    Type: Grant
    Filed: November 5, 1990
    Date of Patent: July 13, 1993
    Assignee: Envirotech Corporation
    Inventors: Douglas E. Hanify, Steven P. Duncan, Robert C. Emmett, Jr., Gunter H. Brox, Lawrence T. O'Connor
  • Patent number: 5116443
    Abstract: A clarifier basin is provided with upflow channels for removing solids from liquid that flows up the channels. The channels are defined by pairs of spaced sheets. Each sheet is provided with three-dimensional (3D) members, such as spherical bubbles or ellipsoids, that are in a two-dimensional array or regular pattern. The sheets are positioned closely adjacent to each other so that the 3D members on one sheet nest with the 3D members of the adjacent sheet to form interstices that collect the solids. The sheets are movable to enlarge the interstices so that air bubbles can flow up a selected channel and remove the solids for collection by a reservoir located above the selected channel. An air supply and the reservoir traverse the channels to remove the solids from the channels on a one-by-one basis. The sheets are formed of a plastic material with a series of protrusions extending from one side in a given pattern.
    Type: Grant
    Filed: March 9, 1990
    Date of Patent: May 26, 1992
    Assignee: Envirotech Corporation
    Inventor: Charles L. Meurer
  • Patent number: 5106499
    Abstract: An apparatus for effecting the separation of filter plates within a filter press is disclosed. The apparatus includes a guide track having mounted thereon a slidably reciprocal carriage. The carriage includes at least one pivoted pawl having an abutment space defined thereon for contacting a filter plate to be transported. The pawl is held in a raised orientation by a resilient spring means. The carriage is driven along the guide track by means of a pressure displaced piston mechanically associated therewith. The piston is housed within a tubular member. Positioned within the tubular member are two pressure chambers, one on each end of the piston. Pressurized fluid is controlledly introduced into one or the other of those chambers to effect a displacement of the piston. The pressure cylinder is of the type generally designated a rodless cylinder.
    Type: Grant
    Filed: March 15, 1990
    Date of Patent: April 21, 1992
    Assignee: Envirotech Corporation
    Inventor: Steven S. Davis
  • Patent number: 5092482
    Abstract: A sludge digester gas-holder is disclosed having a gas-holding cover with ballast members submergible in a liquid medium contained within a chamber circumscribing the upper portion of the tank wall and separate from the main tank cavity.
    Type: Grant
    Filed: March 12, 1990
    Date of Patent: March 3, 1992
    Assignee: Envirotech Corporation
    Inventors: Jeffrey L. Wight, Lynn W. Cook
  • Patent number: 5064532
    Abstract: An apparatus for effecting the separation of filter plates within a filter press is disclosed. The apparatus includes a guide track having mounted thereon a slidably reciprocal carriage. The carriage includes at least one pivoted pawl having an abutment space defined thereon for contacting a filter plate to be transported. The pawl is held in a raised orientation by a resilient spring means. The carriage is driven along the guide track by means of a pressure displaced piston mechanically associated therewith. The piston is housed within a tubular member. Positioned within the tubular member are two pressure chambers, one on each end of the piston. Pressurized fluid is controlledly introduced into one or the other of those chambers to effect a displacement of the piston. The pressure cylinder is of the type generally designated a rodless cylinder.
    Type: Grant
    Filed: September 10, 1990
    Date of Patent: November 12, 1991
    Assignee: Envirotech Corporation
    Inventor: Steven S. Davis
  • Patent number: 5007620
    Abstract: An apparatus for use in bioleach processing of metal-bearing solids is disclosed. The apparatus includes a containment means adapted for containing a slurry made up of metal-bearing solids, a predetermined quantity of water, oxygen, carbon dioxide, nutrients and a species of microorganisms capable of oxidizing some portion of the metal-bearing solids and obtaining energy for growth from that oxidation. The apparatus further includes a plurality of horizontally oriented porous, flexible membrane diffusers adapted for introducing oxygen into the bottom of the reactor vessel in the form of small widely dispersed bubbles.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: April 16, 1991
    Assignee: Envirotech Corporation
    Inventors: Robert C. Emmett, Jr., Lawrence T. O'Connor
  • Patent number: 5006241
    Abstract: An apparatus for effecting the separation of filter plates within a filter press is disclosed. The apparatus includes a guide track having mounted thereon a slidably reciprocal carriage. The carriage includes at least one pivoted pawl having an abutment space defined thereon for contacting a filter plate to be transported. The pawl is held in a raised orientation by a resilient spring means. The carriage is driven along the guide track by means of a pressure displaced piston mechanically associated therewith. The piston is housed within a tubular member. Positioned within the tubular member are two pressure chambers, one on each end of the piston. Pressurized fluid is controlledly introduced into one or the other of those chambers to effect a displacement of the piston. The pressure cylinder is of the type generally designated a rodless cylinder.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: April 9, 1991
    Assignee: Envirotech Corporation
    Inventor: Steven S. Davis
  • Patent number: 4974816
    Abstract: A method and attendant apparatus for use in bioleach processing of metal-bearing solids is disclosed. The method includes the placement into a tank of metal-bearing solids, a predetermined quantity of water, oxygen, carbon dioxide, nutrients and a species of microorganisms capable of oxidizing some portion of the metal-bearing solids and obtaining energy for growth from that oxidation. The slurry formed by this placement is continuously filtered to remove process delimiting metabolic end products products by the oxidation reaction. The ratios of the various slurry components are monitored and controlled to effectuate an optimized environment for oxidation to occur. The attendant apparatus includes a means of introducing oxygen into the bottom of the reactor vessel in the form of small widely dispersed bubbles.
    Type: Grant
    Filed: January 21, 1987
    Date of Patent: December 4, 1990
    Assignee: Envirotech Corporation
    Inventors: Robert C. Emmett, Jr., Lawrence T. O'Connor
  • Patent number: 4968008
    Abstract: A reactor for use in processing metal bearing solids by means of a bioleaching technique is disclosed. The reactor includes an open topped basin, a gantry adapted for displacement along the length of that basin and an agitation means mounted on that gantry for use in agitating a slurry retained within the basin. An air injection system having a plurality of membrane diffusers is positioned within the basin.
    Type: Grant
    Filed: September 26, 1988
    Date of Patent: November 6, 1990
    Assignee: Envirotech Corporation
    Inventors: Robert C. Emmett, Jr., Lawrence T. O'Connor, Gunter H. Brox
  • Patent number: 4933524
    Abstract: A clarifier basin is provided with upflow channels for removing solids from liquid that flows up the channels. The channels are defined by pairs of spaced sheets. Each sheet is provided with three-dimensional (3D) members, such as spherical bubbles or ellipsoids, that are in a two-dimensional array or regular pattern. The sheets are positioned closely adjacent to each other so that the 3D members on one sheet nest with the 3D members of the adjacent sheet to form interstices that collect the solids. The sheets are movable to enlarge the interstices so that air bubbles can flow up a selected channel and remove the solids for collection by a reservoir located above the selected channel. An air supply and the reservoir traverse the channels to remove the solids from the channels on a one-by-one basis.
    Type: Grant
    Filed: March 16, 1989
    Date of Patent: June 12, 1990
    Assignee: Envirotech Corporation
    Inventor: Charles L. Meurer
  • Patent number: 4931190
    Abstract: An improved method for dewatering thin slurries of very fine clay or clay-like material to yield high solids content filter cake, for example, 40% solids and greater, by the use of flocculating agent combinations involving polyethylene oxide-type flocculating agents and polyacarylamide-type flocculating agents. The method generally involves admixing the combination of flocculating agents with the slurry, dewatering the slurry by means of a mechanical dewatering apparatus and feeding the thickened slurry to a belt press filter.
    Type: Grant
    Filed: December 27, 1988
    Date of Patent: June 5, 1990
    Assignee: Envirotech Corporation
    Inventor: Timothy J. Laros
  • Patent number: 4927537
    Abstract: Apparatus for taking up and paying out first and second ends of an endless loop of tape that has an intermediate section. A first reel connected to the first end carries a first coil of the tape. The first coil extends from the first reel and is normally self-expanding and unwinding so as to unwind itself from the first reel. A second reel is connected to the second end for carrying a second coil of the tape. The second coil extends from the second reel and is normally self-expanding so as to unwind itself from the second reel. A drum supports both of the first and second reels for rotation in the same direction. Pulleys guide the intermediate section of the tape from the first reel to the second reel for moving a sludge collector. When the drum is rotated in a first rotary direction, the first coil tends to self-unwind from the first reel and the second coil is wound up on the second reel to move the intermediate section of the tape and the sludge collector.
    Type: Grant
    Filed: March 9, 1989
    Date of Patent: May 22, 1990
    Assignee: Envirotech Corporation
    Inventor: Charles L. Meurer
  • Patent number: 4806239
    Abstract: An apparatus for effecting the separation of filter plates within a filter press is disclosed. The apparatus includes a guide track having mounted thereon a slidably reciprocal carriage. The carriage includes at least one pivoted pawl having an abutment space defined thereon for contacting a filter plate to be transported. The pawl is held in a raised orientation by a resilient spring means. The carriage is driven along the guide track by means of a pressure displaced piston mechanically associated therewith. The piston is housed within a tubular member. Positioned within the tubular member are two pressure chambers, one on each end of the piston. Pressurized fluid is controlledly introduced into one or the other of those chambers to effect a displacement of the piston. The pressure cylinder is of the type generally designated a rodless cylinder.
    Type: Grant
    Filed: November 28, 1986
    Date of Patent: February 21, 1989
    Assignee: Envirotech Corporation
    Inventor: Steven S. Davis
  • Patent number: 4737288
    Abstract: There is disclosed an apparatus and method for conjuncting and separating density differentiated components from a moving carrier liquid. The liquid to be treated flows through zig-zagging separation passages comprising cells extending through a three-dimensional lattice constructed of interconnected triangle pairs each defining a cell therebetween. The shear of the liquid is increased to induce component particle conjunctions by flowing the liquid through a narrow cell passage opening. The shear is then decreased as the liquid flows through the ever-widening cell to a wide cell passage opening to induce separation of the component particles. Heavy and light separated component particles are channeled to a lower side and upper side, respectively, of the lattice along zig-zagging channels.
    Type: Grant
    Filed: March 18, 1985
    Date of Patent: April 12, 1988
    Assignee: Envirotech Corporation
    Inventors: William Melis, Richard D. Saam
  • Patent number: 4732608
    Abstract: A method and attendant apparatus for use in bioleach processing of metal-bearing solids is disclosed. The method includes the placement into a tank of metal-bearing solids, a predetermined quantity of water, oxygen, carbon dioxide, nutrients and a species of microorganisms capable of oxidizing some portion of the metal-bearing solids and obtaining energy for growth from that oxidation. The slurry formed by this placement is continuously filtered to remove process delimiting metabolic end products produced by the oxidation reaction. The ratios of the various slurry components are monitored and controlled to effectuate an optimized environment for oxidation to occur. The attendant apparatus includes a means of introducing oxygen into the bottom of the reactor vessel in the form of small widely dispersed bubbles.
    Type: Grant
    Filed: February 7, 1986
    Date of Patent: March 22, 1988
    Assignee: Envirotech Corporation
    Inventors: Robert C. Emmett, Jr., Lawrence T. O'Connor
  • Patent number: 4728082
    Abstract: A method and attendant apparatus for use in bioleach processing of metal-bearing solids is disclosed. The method includes the placement into a tank of metal-bearing solids, a predetermined quantity of water, oxygen, carbon dioxide, nutrients and a species of microorganisms capable of oxidizing some portion of the metal-bearing solids and obtaining energy for growth from that oxidation. The slurry formed by this placement is continuously filtered to remove process delimiting metabolic end products produced by the oxidation reaction. The ratios of the various slurry components are monitored and controlled to effectuate an optimized environment for oxidation to occur. The attendant apparatus includes a means of introducing oxygen into the bottom of the reactor vessel in the form of small widely dispersed bubbles.
    Type: Grant
    Filed: July 10, 1986
    Date of Patent: March 1, 1988
    Assignee: Envirotech Corporation
    Inventors: Robert C. Emmett, Jr., Lawrence T. O'Connor
  • Patent number: 4710293
    Abstract: An apparatus for automatically removing cake deposits from the surface of filter cloths within a filter press is disclosed. The apparatus includes a rod for suspending the cloth in a substantially inverted "V"-shaped configuration. The cloth is then slackened by lowering a rod over which the cloth is folded. The rod is then suddenly forced upwardly under the driving force of a loading means. The rod draws the cloth to a taut, tensioned condition, imparting a whip-like motion to the fabric of the filter cloth. This imparted motion serves to disengage the cake from the filter cloth.
    Type: Grant
    Filed: December 9, 1985
    Date of Patent: December 1, 1987
    Assignee: Envirotech Corporation
    Inventor: Steven S. Davis
  • Patent number: 4697511
    Abstract: In a dewatering machine for dewatering wet solids in which an elastomeric covered roll applies pressure upon one or more dewatering valves, the improvement whereby the elastomeric roll covering is a multi-layer covering having a graded hardness across the covering layer. A typical covered roll of such a machine is one in which a soft rubber-like material adheres to the surface of the roll and is covered by a harder outer covering.
    Type: Grant
    Filed: July 8, 1985
    Date of Patent: October 6, 1987
    Assignee: Envirotech Corporation
    Inventors: Steven S. Davis, Max A. Mueller, Kenneth F. Janecek
  • Patent number: 4647215
    Abstract: A draft tube mixer is disclosed particularly adapted for use with digestion processes and apparatus wherein a vertical shaft (13) is driven by motor (15) through a suitable drive (14) to rotate a ragless propeller (12). The propeller (12) has a series of three lobes or blades (40-42) which are concentrically arranged at 120.degree. apart positions so that the minimum diameter of the blades are at the ends of a hub (43) from which the blades integrally extend. The blades extend over the length of the hub over about a 360.degree. of rotary motion helix. The blades (40-42) are symmetrical from their ends to the mid points on the vanes from either direction top or bottom so that the propeller is reversible without loss of efficiency.
    Type: Grant
    Filed: March 10, 1986
    Date of Patent: March 3, 1987
    Assignee: Envirotech Corporation
    Inventors: Jack R. Armitage, Ralph B. Haymore
  • Patent number: D312494
    Type: Grant
    Filed: September 22, 1986
    Date of Patent: November 27, 1990
    Assignee: Envirotech Corporation
    Inventor: C. Lonnie Meurer