Search Patents
  • Publication number: 20040082060
    Abstract: An apparatus for forcing airflow through (i.e., aerating) a particulate material consists of a planar bearing surface and a ventilation conduit underlying the planar bearing surface. A plurality of delivery conduits extend between the ventilation conduit and the planar bearing surface with a mouth of the delivery conduits being near the planar bearing surface. A grate, defining a plurality of openings, covers the mouth of each delivery conduit. Each grate has a top surface substantially parallel to the planar bearing surface and positioned at or no more than a select distance below the planar bearing surface. This select distance is close enough to the planar bearing surface to prevent the accumulation of particulate material over the grate as the particulate material is scraped from the planar bearing surface with an implement having a linear edge abutting the planar bearing surface.
    Type: Application
    Filed: October 23, 2002
    Publication date: April 29, 2004
    Applicant: CH2M HILL, Inc.
    Inventor: Jan Allen
  • Patent number: 6383803
    Abstract: A portable and reconfigurable composting apparatus for controlling the airflow to and from a plurality of aerated static composting piles. The composting apparatus includes an air blower having an air intake and an air output. A suction manifold is attached in fluid communication with the air intake of the blower. A discharge manifold is attached in fluid communication with the air output of the blower. A plurality of pile manifolds are connected to the suction manifold and the discharge manifold by a manifold crossover. The manifold crossover includes a pair of dampers which allow the composting apparatus operator to independently select positive or negative air pressure for application to each pile manifold. Each pile manifold is operatively associated with an aerated static compost pile, by means of a series of flexible air lances attached in fluid communication with a pile manifold.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: May 7, 2002
    Assignee: CH2M Hill, Inc.
    Inventors: Jan Allen, Chuck Kemper
  • Patent number: 6534306
    Abstract: A biofilter apparatus includes at least one container having a height, length, and width containing a deep, low density, porous media within the container. An airflow apparatus is constructed and arranged to deliver a flow of air to be treated to the filter media. The airflow apparatus provides at least 37.5 cfm/ft2 with the porous media creating a backpressure of not more than about 10 inches of water. The media preferably consists of about 30-40% shredded tree bark particles, about 30-40% shredded wood, and about 30-40% composted wood sized such that 95% of the media will pass through a three inch screen and be retained by a 0.5 inch screen. A fluid mister may be provided in fluid communication with the flow of the air to be treated for introducing humidity to the air. The method for treating air via biofiltration utilizes the biofiltration apparatus discussed above and includes directing contaminated air into the container through the airflow apparatus and through the media at at least 37.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: March 18, 2003
    Assignee: CH2M Hill, Inc.
    Inventor: Jan Allen
  • Patent number: 8313921
    Abstract: A method of biodegrading municipal solid waste includes providing a quantity of municipal solid waste and promoting anaerobic digestion in the quantity of municipal solid waste by methanogenic organisms to produce methane. The methane production is monitored and when it is determined that production of methane from the quantity of municipal solid waste has subsided, aerobic digestion of the quantity of municipal solid waste is promoted. A gas collection system in operative association with the quantity of organic waste collects biogas and the biogas is monitored and the rate of gas collection is adjusted as necessary to maximize methane collection. A leachate collection system collects leachate from the quantity of municipal solid waste and circulates the leachate back to the quantity of organic waste during the anaerobic digestion and aerobic digestion steps.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: November 20, 2012
    Assignee: CH2M Hill, Inc.
    Inventors: Tom Kraemer, Charles Kemper, Jan Allen