Patents by Inventor Swarna Muthukrishnan

Swarna Muthukrishnan 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).

  • Patent number: 9505644
    Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus. The process includes an anoxic tank that receives at least two streams, including plant influent wastewater and return activated sludge. These streams are mixed in the anoxic tank to promote phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: November 29, 2016
    Assignee: AMERICAN WATER WORKS COMPANY, INC.
    Inventors: Eugenio Giraldo, Yanjin Liu, Swarna Muthukrishnan
  • Publication number: 20140263042
    Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus. The process includes an anoxic tank that receives at least two streams, including plant influent wastewater and return activated sludge. These streams are mixed in the anoxic tank to promote phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.
    Type: Application
    Filed: May 30, 2014
    Publication date: September 18, 2014
    Applicant: AMERICAN WATER WORKS COMPANY, INC.
    Inventors: EUGENIO GIRALDO, YANJIN LIU, SWARNA MUTHUKRISHNAN
  • Patent number: 8747671
    Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus. The process includes an anoxic tank that receives at least two streams, including plant influent wastewater and return activated sludge. These streams are mixed in the anoxic tank to promote phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: June 10, 2014
    Assignee: American Water Works Company, Inc.
    Inventors: Eugenio Giraldo, Yanjin Liu, Swarna Muthukrishnan
  • Publication number: 20120067816
    Abstract: Methods and systems are provided for treating wastewater to simultaneously remove nitrogen, carbon, and phosphorus. The process includes an anoxic tank that receives at least two streams, including plant influent wastewater and return activated sludge. These streams are mixed in the anoxic tank to promote phosphorus release and fermentation of particulate and dissolved organic matter. The mixed liquor is transferred to an aerated tank having low dissolved oxygen concentrations to promote development of phosphorus-release bacteria that is eventually recycled to the anoxic tank by way of the return activated sludge. Simultaneous nitrification, denitrification, and phosphorus release occur in the aerated tank. A membrane tank separates treated effluent from activated sludge in a membrane tank.
    Type: Application
    Filed: September 20, 2010
    Publication date: March 22, 2012
    Applicant: AMERICAN WATER WORKS COMPANY, INC.
    Inventors: EUGENIO GIRALDO, YANJIN LIU, SWARNA MUTHUKRISHNAN
  • Patent number: 8012352
    Abstract: Methods and systems are provided for reducing ammonia partially by a denitrification process. A stream containing ammonia is contacted with oxygen to form a first product stream in low dissolved oxygen conditions. The ratio of oxygen to nitrogen is about 2.28 g O2/g N—NH3 (2.28 grams of oxygen per gram of nitrogen in ammonia) or less. The first product stream is then exposed to organic matter in an amount of 0.57 g COD/g N—NH3 (0.57 grams of chemical oxygen demand per gram of nitrogen in ammonia). This microbial reaction ultimately produces nitrogen gas, water, and carbon dioxide.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: September 6, 2011
    Assignee: American Water Works Company, Inc.
    Inventors: Eugenio Giraldo, Yanjin Liu, Swarna Muthukrishnan