Patents Assigned to Ztek Corporation
  • Patent number: 5858314
    Abstract: A natural gas reformer comprising a stack of thermally conducting plates interspersed with catalyst plates and provided with internal or external manifolds for reactants. The catalyst plate is in intimate thermal contact with the conducting plates so that its temperature closely tracks the temperature of the thermally conducting plate, which can be designed to attain a near isothermal state in-plane to the plate. One or more catalysts may be used, distributed along the flow direction, in-plane to the thermally conducting plate, in a variety of optional embodiments. The reformer may be operated as a steam reformer or as a partial oxidation reformer. When operated as a steam reformer, thermal energy for the (endothermic) steam reforming reaction is provided externally by radiation and/or conduction to the thermally conducting plates. This produces carbon monoxide, hydrogen, steam and carbon dioxide.
    Type: Grant
    Filed: April 12, 1996
    Date of Patent: January 12, 1999
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Ethan D. Hoag
  • Patent number: 5858568
    Abstract: A power supply system for enhancing the economic viability of different modes of transportation that incorporate fuel cells to generate electricity. For example, the power supply system of the present invention provides for the off-board use of the electric power generated by an on-board power plant, such as a fuel cell, of a mobile vehicle power system, such as an electric car. Off-board use, or use remote from the vehicle, of the electrical power includes the delivery of power to a remote site. Off-board stations are provided for delivery of fuel to the vehicle and/or for receiving the electrical power generated by the fuel cell. The off-board station and the vehicle are appropriately equipped for quick and easy interconnection such that electrical power is drawn from the fuel cell for off-board use.
    Type: Grant
    Filed: September 19, 1996
    Date of Patent: January 12, 1999
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Robin Y. P. Ong
  • Patent number: 5833822
    Abstract: An electrochemical converter assembly having one or more converter elements having a peripheral edge. The converter element includes a series of electrolyte plates having an oxidizer electrode material on one side and a fuel electrode material on the opposing side, and a series of interconnector plates, alternately stacked with the electrolyte plates, that provide electrical contact with the electrolyte plates. The interconnector plate has a textured pattern that forms reactant-flow passageways. The converter assembly has a low pressure drop configuration that includes at least one passageway which is disposed generally in the central region of the converter element, for introducing one input reactant thereto, and at least one second passageway, for introducing the other reactant. A third passageway, outwardly spaced from the second passageway removes spent fuel from the reactant-flow passageways, and thus from the converter element.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: November 10, 1998
    Assignee: Ztek Corporation
    Inventor: Michael S. Hsu
  • Patent number: 5747185
    Abstract: A sulfur-tolerant electrochemical converter having low internal resistance that is capable of directly processing hydrocarbon fuel having a sulfur component of up to about 50 ppm, and in excess of this amount, without suffering permanent structural damage or suffering a significant and/or permanent decrease in overall operating performance. The electrochemical converter is a high temperature fuel cell that has an operating temperature between about 600.degree. C. and about 1200.degree. C. and is capable of internally vaporizing and/or reforming the hydrocarbon fuel. One or more of the converter constituents, such as the interconnector, the contact surfaces of the interconnector, the fuel electrode, and the oxidizer electrode, is composed of a selected mixture containing chromium oxide and an alkaline metal oxide.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: May 5, 1998
    Assignee: Ztek Corporation
    Inventor: Michael S. Hsu
  • Patent number: 5693201
    Abstract: A turbine power system that includes a compressor for compressing a first medium, and an electrochemical converter in communication with the compressor and adapted to receive the first medium and a second medium. The converter is configured to allow an electrochemical reaction between the first and second mediums, thereby generating electricity and producing exhaust having a selected elevated temperature. The power system further includes a turbine in fluid communication with the electrochemical converter and adapted to receive the converter exhaust, such that the turbine converts the electrochemical converter exhaust into rotary energy and electricity. The system can further include a steam generator and a steam turbine that produces electricity. The electrochemical converter is utilized herein as an electrochemical combustor-replacement (ECCR) or as a fuel cell for combustor-replacement (FCCR).
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: December 2, 1997
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Ethan D. Hoag
  • Patent number: 5501781
    Abstract: An electrochemical converter assembly that significantly reduces the size of the dedicated thermal processing heat exchangers associated with the converter. This reduction is achieved by heating the input reactants of the electrochemical converter assembly inside the axial manifolds. This heating configuration thus relies upon an effective heat transfer mechanism located within the manifolds, and particularly within the manifold surfaces. In a preferred embodiment, the heating of the reactants occurs at the entrance region of the planar gap formed between the interconnector plates and the electrolyte plates. This heating is facilitated by the conduction of heat through the highly thermally conductive interconnector plate to an extended heating surface disposed within the manifold.
    Type: Grant
    Filed: August 8, 1994
    Date of Patent: March 26, 1996
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Ethan D. Hoag
  • Patent number: 5500306
    Abstract: A system and method for converting organic material to electricity includes the steps of collecting a quantity of organic material, generating biogas from the material, and passing the biogas through an energy converter. Biogas is generated from the organic material by an anaerobic filter, and electricity is converted from the biogas by an energy converter, such as a high efficiency solid oxide fuel cell. To further increase the efficiency of the system, an anaerobic digester is used for treating a solid or sludge component of the organic material to generate additional biogas. In one embodiment of the invention, solar energy is used to maintain the anaerobic digester at an elevated temperature. Further efficiency enhancing measures include the recirculation of both the sludge and liquid components of the organic material to obtain additional biogas.
    Type: Grant
    Filed: October 6, 1993
    Date of Patent: March 19, 1996
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Irvine W. Wei
  • Patent number: 5338622
    Abstract: A heat exchanging apparatus including a working fluid and a structure for exchanging heat between the working fluid and an external environment. The structure includes at least one wall element having an external surface exposed to the external environment and an internal surface exposed to the working fluid such that heat can be exchanged between the environment and the working fluid by conductive heat transfer through the wall element. The apparatus further includes a reservoir element for providing a reservoir for the working fluid and a distribution element for distributing the working fluid along the wall element to provide isothermal heat exchange between the working fluid and the external environment. In one embodiment, the structure can be a double lumen tubular structure having an inner lumen which provides a reservoir for the working fluid, and an lumen where heat is exchanged between the working fluid and an external environment.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: August 16, 1994
    Assignee: Ztek Corporation
    Inventors: Michael S. Hsu, Ethan D. Hoag