Patents by Inventor David DeWaard

David DeWaard 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: 20200094174
    Abstract: A rotary screen separator includes a screen having a substantially cylindrical shape extending from a feed end to a discharge end along a horizontal longitudinal axis. The screen is perforated in a plurality of discrete regions. The regions including at least a first perforation region wherein the screen is perforated in a first perforation pattern and a second perforation wherein the screen is perforated in a second perforation pattern. The first perforation pattern is sized to allow liquid and finer particulate matter to pass through the perforations and the second perforation pattern is sized to allow liquid and coarser particulate matter to pass through the perforations in the second perforation pattern. A first vane structure is helically shaped at a first vane depth having a first vane pitch and handedness selected to advance feedstock within the screen as the screen is rotated in operation.
    Type: Application
    Filed: November 12, 2019
    Publication date: March 26, 2020
    Inventor: David DeWaard
  • Publication number: 20200060220
    Abstract: A method and apparatus for collecting agricultural manure in a confined animal feeding operation includes a separator which receives heavy manure removing particulate from suspension to produce light manure. Heavy manure is collected to a volume of heavy manure sufficient to substantially fill the first tank. Within the first tank, particulate migrates, due to the influence of gravity to form a layer containing manure comprising a lesser density of particulate than is present in the volume of heavy manure. Additional heavy manure buoys the layer such that the upper surface exceeds a height of a weir. The weir is situated in a channel communicating between the first tank and a second tank configured to receive light manure from the separator.
    Type: Application
    Filed: November 4, 2019
    Publication date: February 27, 2020
    Inventor: David DeWaard
  • Patent number: 10568298
    Abstract: A method and apparatus for collecting agricultural manure in a confined animal feeding operation includes a separator which receives heavy manure removing particulate from suspension to produce light manure. Heavy manure is collected to a volume of heavy manure sufficient to substantially fill the first tank. Within the first tank, particulate migrates, due to the influence of gravity to form a layer containing manure comprising a lesser density of particulate than is present in the volume of heavy manure. Additional heavy manure buoys the layer such that the upper surface exceeds a height of a weir. The weir is situated in a channel communicating between the first tank and a second tank configured to receive light manure from the separator.
    Type: Grant
    Filed: May 16, 2017
    Date of Patent: February 25, 2020
    Assignee: Dari-Tech, Inc.
    Inventor: David DeWaard
  • Publication number: 20190224595
    Abstract: A feed system for a rotary screen separator has a feed housing and a feed lid movably attached to the feed housing. The feed housing has a feed chamber, an inlet opening, and an outlet opening. The feed chamber defines a proximal portion adjacent to the inlet opening and a distal portion at least a portion of which is adjacent to the an outlet opening. A cross-sectional area of at least a portion of the proximal portion is greater than a cross-sectional area of the distal portion. The feed lid is movably attached to the feed housing such that the feed lid covers the outlet opening in a closed position, and does not cover the outlet opening in at least one open position.
    Type: Application
    Filed: April 1, 2019
    Publication date: July 25, 2019
    Inventor: David DeWaard
  • Patent number: 10286340
    Abstract: A feed system for a rotary screen separator has a feed housing and at least one feed lid movably attached to the feed housing. The feed housing has a feed chamber, an inlet opening, and at least one outlet opening. The feed chamber defines a proximal portion adjacent to the inlet opening and a distal portion at least a portion of which is adjacent to the at least one outlet opening. A cross-sectional area of at least a portion of the proximal portion is greater than a cross-sectional area of the distal portion. The at least one feed lid is movably attached to the feed housing such that the at least one feed lid covers the at least one outlet opening in a closed position, and does not cover the at least one outlet opening in at least one open position.
    Type: Grant
    Filed: May 27, 2015
    Date of Patent: May 14, 2019
    Assignee: Daritech, Inc.
    Inventor: David DeWaard
  • Publication number: 20190119177
    Abstract: A system and method for reclaiming nutrients from dairy manure includes a centrifuge for separating a liquid fraction of the manure from a solid fraction comprising organic material; a mechanical vapor recompression evaporator (“MVR”) to receive the liquid fraction from the centrifuge and evaporating the liquid fraction by mechanical vapor recompression to produce ammonia-laden water vapor and a concentrated nutrient slurry; a dryer for drying the nutrient slurry to a selected moisture content to be available as an ingredient in compounded fertilizer; and an ammonia stripping tower assembly to receive ammonia-laden water vapor from the MVR and from it to precipitate ammonium sulphate salt and condense water as separate products.
    Type: Application
    Filed: August 3, 2018
    Publication date: April 25, 2019
    Applicant: DanTech, Inc.
    Inventors: David DeWaard, Josh McCort, Michael Klapper
  • Publication number: 20190119174
    Abstract: To produce fertilizer, a system and method concentrates manure slurry in a mechanical vapor recompression evaporator (“MVR”) having a heat exchanger. The MVR receives the manure slurry within a first side to evaporate ammonia laden-water vapor from the slurry, leaving a nutrient concentrate. A compressor raises the evaporated ammonia-laden water vapor to a higher energy state. Within a second side of the heat exchanger, the compressed water vapor conveys heat to the slurry. Ammonia-laden water condenses in the second side at a process temperature to be conveyed to an ammonia stripping tower where the ammonia-laden water is dispersed into ammonia-laden water droplets. In the tower, a flow of air is directed across a surface of the ammonia-laden water droplets, the process temperature having been selected to promote the escape of ammonia gas from the ammonia-laden water droplets, the flow of air provided to entrain ammonia gas in the flow.
    Type: Application
    Filed: October 24, 2017
    Publication date: April 25, 2019
    Inventors: David DeWaard, Josh McCort, Michael Klapper
  • Publication number: 20190119179
    Abstract: To produce fertilizer, a system and method concentrates manure slurry in a mechanical vapor recompression evaporator (“MVR”) having a heat exchanger. The MVR receives the manure slurry within a first side to evaporate ammonia laden-water vapor from the slurry, leaving a nutrient concentrate. A compressor raises the evaporated ammonia-laden water vapor to a higher energy state. Within a second side of the heat exchanger, the compressed water vapor conveys heat to the slurry. Ammonia-laden water condenses in the second side at a process temperature to be conveyed to an ammonia stripping tower where the ammonia-laden water is dispersed into ammonia-laden water droplets. In the tower, a flow of air is directed across a surface of the ammonia-laden water droplets, the process temperature having been selected to promote the escape of ammonia gas from the ammonia-laden water droplets, the flow of air provided to entrain ammonia gas in the flow.
    Type: Application
    Filed: August 6, 2018
    Publication date: April 25, 2019
    Applicant: DariTech, Inc.
    Inventors: David DeWaard, Josh McCort, Michael Klapper
  • Publication number: 20170283338
    Abstract: A digester system comprising a primary digester tank containing a primary feed material portion, a secondary digester tank containing a secondary feed material portion, a first conduit connected between the primary digester tank and the secondary digester tank to define a primary tank lower opening within the primary digester tank and a secondary digester tank lower opening within the secondary digester tank, and a flow control valve configured to allow or prevent flow of fluid through the first conduit. When the flow control valve is configured to allow flow of fluid through the first conduit, a portion of the primary feed material portion flows from the primary digester tank to the secondary digester tank to form the secondary feed material portion.
    Type: Application
    Filed: April 5, 2017
    Publication date: October 5, 2017
    Inventor: David DeWaard
  • Patent number: 9751787
    Abstract: A digester system for digesting feed material comprises a digester tank, a thickener, and a seal system. The digester tank generates a first digested material and biogas from the feed material. The thickener is operatively connected to the digester tank to remove a second digested material from the feed material to alter a solid content of the feed material in the digester tank. The seal system substantially prevents the thickener from removing biogas from the feed material with the second digested material.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: September 5, 2017
    Assignee: Daritech, Inc.
    Inventor: David DeWaard
  • Publication number: 20170245458
    Abstract: A method and apparatus for collecting agricultural manure in a confined animal feeding operation includes a separator which receives heavy manure removing particulate from suspension to produce light manure. Heavy manure is collected to a volume of heavy manure sufficient to substantially fill the first tank. Within the first tank, particulate migrates, due to the influence of gravity to form a layer containing manure comprising a lesser density of particulate than is present in the volume of heavy manure. Additional heavy manure buoys the layer such that the upper surface exceeds a height of a weir. The weir is situated in a channel communicating between the first tank and a second tank configured to receive light manure from the separator.
    Type: Application
    Filed: May 16, 2017
    Publication date: August 31, 2017
    Inventor: David DeWaard
  • Publication number: 20170209818
    Abstract: A processing system for processing raw slurry material comprising at least liquid, sand, and contaminates comprises a barrel member, at least one transport member, at least one separator member, and a drive system. As the drive system rotates the barrel member about the barrel longitudinal axis, a portion of the raw slurry material is transported through a pre-processing portion of the processing chamber. At least a portion of the liquid and at least a portion of the contaminates in the raw slurry material flows back down the pre-processing portion of the processing chamber towards a barrel inlet. At least one intermediate opening is arranged such that at least a portion of the contaminates in the raw slurry material flowing down through the pre-processing portion of the processing chamber passes through the at least one intermediate opening.
    Type: Application
    Filed: March 20, 2017
    Publication date: July 27, 2017
    Inventor: David DeWaard
  • Patent number: 9610521
    Abstract: A processing system for separating raw slurry material into particulate materials and liquid materials comprising a processing structure, a frame, and a drive motor. The processing structure defines a processing chamber, an inlet, an outlet, and at least one pre-processing opening arranged between the inlet and the outlet. The frame supports the processing structure. Operation of the drive motor rotates the processing structure such that at least some of the particulate materials in the raw slurry material are transported from the inlet to the outlet, at least some of the liquid materials in the raw slurry material are allowed to flow back towards the inlet, and at least some of the liquid materials and at least some of the particulate materials are allowed to flow through the at least one pre-processing opening.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: April 4, 2017
    Assignee: Daritech, Inc.
    Inventor: David DeWaard
  • Patent number: 9597618
    Abstract: A processing system for processing raw slurry material has a barrel member, at least one transport member, and at least one separator member. The barrel member defines a processing chamber and at least one intermediate opening. The processing chamber defines a pre-processing portion and a separator portion. The at least one transport member is arranged within the pre-processing portion of the processing chamber. The at least one separator member is arranged within the separator portion of the processing chamber and configured to define at least one separator gap. As the barrel member rotates about a longitudinal axis thereof, the at least one transport member transports at least a portion of the raw slurry material through the pre-processing portion of the processing chamber, and the at least one separator member transports at least a portion of the raw slurry material through the separator portion of the processing chamber.
    Type: Grant
    Filed: November 17, 2014
    Date of Patent: March 21, 2017
    Assignee: Daritech, Inc.
    Inventor: David DeWaard
  • Publication number: 20160121339
    Abstract: A separation system for separating solids from a slurry of waste material, the separation system comprising a housing, a drum assembly, and a drive assembly. The housing defines a collection chamber. Liquid within the collection chamber defines a liquid level. The drum assembly defines a perforated cylindrical wall and the drum assembly is supported such that at least a portion of the drum assembly is below the liquid level. The drive assembly rotates the drum assembly relative to the housing.
    Type: Application
    Filed: October 30, 2015
    Publication date: May 5, 2016
    Inventor: David DeWaard
  • Publication number: 20160106057
    Abstract: A method and apparatus for collecting agricultural manure in a confined animal feeding operation includes a separator which receives heavy manure removing particulate from suspension to produce light manure. Heavy manure is collected to a volume of heavy manure sufficient to substantially fill the first tank. Within the first tank, particulate migrates, due to the influence of gravity to form a layer containing manure comprising a lesser density of particulate than is present in the volume of heavy manure. Additional heavy manure buoys the layer such that the upper surface exceeds a height of a weir. The weir is situated in a channel communicating between the first tank and a second tank configured to receive light manure from the separator.
    Type: Application
    Filed: May 4, 2015
    Publication date: April 21, 2016
    Inventor: David DeWaard
  • Publication number: 20150343343
    Abstract: A feed system for a rotary screen separator has a feed housing and at least one feed lid movably attached to the feed housing. The feed housing defines has a feed chamber, an inlet opening, and at least one outlet opening. The feed chamber defines a proximal portion adjacent to the inlet opening and a distal portion at least a portion of which is adjacent to the at least one outlet opening. A cross-sectional area of at least a portion of the proximal portion is greater than a cross-sectional area of the distal portion. The at least one feed lid is movably attached to the feed housing such that the at least one feed lid covers the at least one outlet opening in a closed position, and does not cover the at least one outlet opening in at least one open position.
    Type: Application
    Filed: May 27, 2015
    Publication date: December 3, 2015
    Inventor: David DeWaard
  • Publication number: 20150343344
    Abstract: A cleaning system for a screen of a rotary screen separator for processing feed material comprising liquids and solids has a housing, an air source, and a conduit system. The housing defines at least one housing chamber, at least one inlet opening, and at least one outlet slot. The conduit system is operatively connected between the inlet opening of the housing and the air source. Air flows from the air source through conduit system, through the inlet opening, into the housing chamber, and out of the housing chamber through the at least one outlet slot in at least one air flow stream extending along a flow plane. The housing is arranged relative to the screen of the rotatory screen separator such that the air flow stream impinges on the screen to remove debris from the screen.
    Type: Application
    Filed: June 1, 2015
    Publication date: December 3, 2015
    Inventor: David DeWaard
  • Publication number: 20150251112
    Abstract: A dewatering system for removing liquids from feed material comprises a pre-processing stage separator, an output roller press, and a control system. The pre-processing stage separator processes the feed material at a pre-processing rate to obtain a pre-processed mat, where the pre-processed mat contains less liquid than the feed material. The output roller press processes the pre-processed mat at an output rate to obtain an output mat, where the output mat contains less liquid than the pre-processed mat. The control system controls the pre-processing rate based on at least one characteristic of the output mat to maintain the at least one characteristic of the output mat within a predetermined range.
    Type: Application
    Filed: April 29, 2015
    Publication date: September 10, 2015
    Inventor: David DeWaard
  • Publication number: 20150122747
    Abstract: A processing system for separating raw slurry material into particulate materials and liquid materials comprising a processing structure, a frame, and a drive motor. The processing structure defines a processing chamber, an inlet, an outlet, and at least one pre-processing opening arranged between the inlet and the outlet. The frame supports the processing structure. Operation of the drive motor rotates the processing structure such that at least some of the particulate materials in the raw slurry material are transported from the inlet to the outlet, at least some of the liquid materials in the raw slurry material are allowed to flow back towards the inlet, and at least some of the liquid materials and at least some of the particulate materials are allowed to flow through the at least one pre-processing opening.
    Type: Application
    Filed: January 6, 2015
    Publication date: May 7, 2015
    Inventor: David DeWaard