Patents Assigned to Columbus Water Works
  • Biosolids flow-through thermophilic treatment process
    Patent number: 6908555
    Abstract: A method of treating wastewater sludge includes pumping, continuously, raw sludge into a first digester and treating the raw sludge at a specific temperature of between about 51° C. to 60° C.; transferring the treated wastewater sludge to a batch tank; treating the wastewater sludge in the batch tank, anaerobically, at a thermophilic temperature which is not more than 2° C. warmer than the specific temperature in the first digester; and disposing of the treated wastewater sludge as a Class A biosolid. A wastewater sludge treatment system includes a first thermophilic digester for treating raw wastewater sludge at a specific temperature in a range of between about 51° C. to 60° C., and discharging a treated wastewater sludge; a batch tank for receiving the treated wastewater sludge discharged from the first digester and for thermophilically treating sludge at a temperature in a range of between about 51° C. to 60° C. and not more than 2° C.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: June 21, 2005
    Assignee: Columbus Water Works
    Inventors: Clifford J. Arnett, Joseph B. Farrell, Daniel T. Hull, III, Steven J. Krugel, Perry L. Schafer, Billy G. Turner, Warren R. Uhte, John L. Willis
  • Biosolids flow-through thermophilic treatment process
    Publication number: 20040011718
    Abstract: A method of treating wastewater sludge includes pumping, continuously, raw sludge into a first digester and treating the raw sludge at a specific temperature of between about 51° C. to 60° C.; transferring the treated wastewater sludge to a batch tank; treating the wastewater sludge in the batch tank, anaerobically, at a thermophilic temperature which is not more than 2° C. warmer than the specific temperature in the first digester; and disposing of the treated wastewater sludge as a Class A biosolid. A wastewater sludge treatment system includes a first thermophilic digester for treating raw wastewater sludge at a specific temperature in a range of between about 51° C. to 60° C., and discharging a treated wastewater sludge; a batch tank for receiving the treated wastewater sludge discharged from the first digester and for thermophilically treating sludge at a temperature in a range of between about 51° C. to 60° C. and not more than 2° C.
    Type: Application
    Filed: April 28, 2003
    Publication date: January 22, 2004
    Applicant: Columbus Water Works
    Inventors: Clifford J. Arnett, Joseph B. Farrell, Daniel T. Hull, Steven J. Krugel, Perry L. Schafer, Billy G. Turner, Warren R. Uhte, John L. Willis