Patents by Inventor Prasad Duggirala

Prasad Duggirala 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: 20150034563
    Abstract: Dewatering agents and methods of dewatering wastewater slurries are provided. Also disclosed are methods for improving the separation of solids from water. The water may be produced water, raw water, or wastewater, for example. The dewatering agents can be in solutions and the dewatering agent solutions may include flocculants, soy based components, and surfactants. The soy based components can include, for example, soy flour and soy protein.
    Type: Application
    Filed: July 31, 2013
    Publication date: February 5, 2015
    Applicant: ECOLAB USA INC.
    Inventors: Prasad Duggirala, Weiguo Cheng, Darlington Mlambo
  • Patent number: 8884049
    Abstract: The invention provides a method of efficiently producing branched, cyclic glycerol-based polymer surface active products having ester and alkyl functional groups with a co-product as anti-biodegrading agent from inexpensive readily available glycerol monomer. The method involves polymerizing glycerol or glycerol with at least another monomer to multiple other monomers in the presence of particular amount of a strong base as the catalyst under a particular distillation environment. The polyol then undergoes esterification, alkylation and crosslinking in presence of particular amount of a catalyst under a particular low activity atmospheric environment. The glycerol-based polymer surface active products produced by the inventive method are beneficial for reducing lignin, extractives and rejects levels in pulping process of papermaking industry.
    Type: Grant
    Filed: May 31, 2012
    Date of Patent: November 11, 2014
    Assignee: Nalco Company
    Inventors: Xiaojin Harry Li, Prasad Duggirala, Joanna L. Shih
  • Patent number: 8858759
    Abstract: Methods and compositions for improving dewatering efficiency during a papermaking or pulp drying process are disclosed. The methods can include a step of adding a dewatering agent solution to a location on a paper machine or pulp drying machine. The dewatering agent solution can include a soy based component. The soy based component can be soy flour or soy protein. The dewatering agent solution can be added to a wet end location of the pulp drying machine or paper machine or it can be sprayed onto a paper sheet prior to entering the press section of a paper machine. Additional dewatering agent solutions can also be added. The additional dewatering agent solutions can include cationic polymers or surfactants.
    Type: Grant
    Filed: July 10, 2013
    Date of Patent: October 14, 2014
    Assignee: Ecolab USA Inc.
    Inventors: Prasad Duggirala, Weiguo Cheng, Luiz W. Pace
  • Patent number: 8617356
    Abstract: Compositions and processes that enhance the brightness and improve color of pulp or paper when applied during different stages of the papermaking process involving optical brighteners are identified. Used in combination with optical brighteners and/or chelants the described agents produce a synergistic effect not previously identified in the paper process.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: December 31, 2013
    Assignee: Nalco Company
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20130153506
    Abstract: Disclosed is a cost effective method of clarifying wastewater. The method comprises the steps of providing wastewater and adding a substance to the wastewater. The substance comprises a porous particulate material. The porous particulate material may be perlite, and the substance may additionally comprise a coagulant.
    Type: Application
    Filed: December 16, 2011
    Publication date: June 20, 2013
    Inventors: Prasad Duggirala, Weiguo Cheng
  • Patent number: 8440052
    Abstract: An apparatus for feeding one or more chemicals into a process stream of a pulp process is disclosed, as well as a method of utilizing the apparatus for feeding one or more chemicals into a pulp process is disclosed.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: May 14, 2013
    Assignee: Nalco Company
    Inventors: Prasad Duggirala, Michael Murcia, Tommy Jacobson, Mika Salonen, Martti O. Latva
  • Publication number: 20120238776
    Abstract: The invention provides a method of efficiently producing branched, cyclic glycerol-based polymer surface active products having ester and alkyl functional groups with a co-product as anti-biodegrading agent from inexpensive readily available glycerol monomer. The method involves polymerizing glycerol or glycerol with at least another monomer to multiple other monomers in the presence of particular amount of a strong base as the catalyst under a particular distillation environment. The polyol then undergoes esterification, alkylation and crosslinking in presence of particular amount of a catalyst under a particular low activity atmospheric environment. The glycerol-based polymer surface active products produced by the inventive method are beneficial for reducing lignin, extractives and rejects levels in pulping process of papermaking industry.
    Type: Application
    Filed: May 31, 2012
    Publication date: September 20, 2012
    Inventors: Xiaojin Harry Li, Prasad Duggirala, Joanna L. Shih
  • Publication number: 20120211185
    Abstract: Compositions and processes that enhance the brightness and improve color of pulp or paper when applied during different stages of the papermaking process involving optical brighteners are identified. Used in combination with optical brighteners and/or chelants the described agents produce a synergistic effect not previously identified in the paper process.
    Type: Application
    Filed: April 30, 2012
    Publication date: August 23, 2012
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Patent number: 8246780
    Abstract: Compositions and processes that preserve and enhance the brightness and improve color of pulp or paper when applied during different stages of the papermaking process are identified. The composition and method maintains and/or enhances brightness, prevent yellowing, and enhances the performance of paper products. Used in combination with optical brighteners and/or chelants the described agents produce a synergistic effect not previously identified in the paper process.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: August 21, 2012
    Assignee: Nalco Company
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20120073775
    Abstract: A method for monitoring the deposition of organic deposits from a liquid or slurry in a papermaking process is disclosed. Also disclosed is a method for measuring the effectiveness of inhibitors that decrease the deposition of organic deposits in a papermaking process. The method may involve monitoring the deposition of organic deposits of a liquid or slurry that simulates the conditions of a papermaking process. The methods may comprise the steps of monitoring the rate of deposition of organic deposits; adding an inhibitor that decreases the deposition of organic deposits from the liquid or slurry; and optionally re-measuring the rate of deposition of organic deposits from the liquid or slurry onto the quartz crystal microbalance, with the rates of deposition determined by measuring the vibration frequency of the quartz crystal microbalance.
    Type: Application
    Filed: November 28, 2011
    Publication date: March 29, 2012
    Inventors: Prasad Duggirala, Sergey Sheychenko
  • Publication number: 20100224333
    Abstract: The invention provides a composition of matter and a method, which enhance the process of mechanically pulping paper precursors. The composition of matter includes a small quantity of a reducing agent and a source of alkali. When added to the pulped material, e.g., wood chips, before or during mechanical pulping, the composition reduces the energy cost of the operation. In addition, not only does the composition also does not reduce the brightness of pulp, the composition can also enhance the effectiveness of subsequent bleaching processes.
    Type: Application
    Filed: March 9, 2009
    Publication date: September 9, 2010
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20070131365
    Abstract: A method of enhancing brightness of paper made from mechanical pulps or recycled pulps that comprise: adding an effective amount of one or more chelants and one or more surfactants to a bleaching stage of a papermaking process that involves the addition of hydrosulfite is disclosed.
    Type: Application
    Filed: December 14, 2005
    Publication date: June 14, 2007
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20070131373
    Abstract: A method of decreasing the rate of photoyellowing in paper containing mechanical pulp comprising: applying an aqueous solution containing an effective amount of one or more salts of thiocyanic acid on the surface of a paper sheet in a papermaking process.
    Type: Application
    Filed: December 14, 2005
    Publication date: June 14, 2007
    Inventors: Sergey Shevchenko, Prasad Duggirala
  • Publication number: 20070062653
    Abstract: Compositions and processes that preserve and enhance the brightness and improve color of pulp or paper when applied during different stages of the papermaking process are identified. The composition and method maintains and/or enhances brightness, prevent yellowing, and enhances the performance of paper products. Used in combination with optical brighteners and/or chelants the described agents produce a synergistic effect not previously identified in the paper process.
    Type: Application
    Filed: March 23, 2006
    Publication date: March 22, 2007
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20060281191
    Abstract: A method for monitoring the deposition of organic deposits from a liquid or slurry in a papermaking process is disclosed. The method involves measuring the rate of deposition of organic deposits from the liquid or slurry of a papermaking process on to a quartz crystal microbalance having a top side in contact with the liquid or slurry and a second, bottom side isolated from the liquid or slurry. Also disclosed is a method for measuring the effectiveness of inhibitors that decrease the deposition of organic deposits in a papermaking process. The method involves monitoring the deposition of organic deposits of a liquid or slurry from a papermaking process or from a liquid or slurry that simulates a liquid or slurry found in a papermaking process.
    Type: Application
    Filed: June 9, 2005
    Publication date: December 14, 2006
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20060229393
    Abstract: A Penetrant compound that preserves and enhances the brightness of a ligno-cellulosic material comprising (i) a reductive nucleophilic agent and (ii) a chelant in a paper or tissue machine. This Penetrant compound preserves and enhances the brightness of a ligno-cellulosic material when applied during different stages of the papermaking process. Penetrant compound maintains and/or enhances brightness, prevent yellowing, and enhances the performance of optical brighteners of pulp or a paper sheet produced by methods wherein the penetrant compound is applied in the papermaking process.
    Type: Application
    Filed: April 8, 2005
    Publication date: October 12, 2006
    Inventors: Prasad Duggirala, Sergey Shevchenko
  • Publication number: 20050217813
    Abstract: Mechanical or Chemical pulp is treated with about 0.01 weight % to about 5 weight % of a Mixture. The Mixture is water; diethylenetriaminepentakis(methyl)phosphonic acid or its known salts; polyacrylic acid or its known salts; and optionally one or more inert compounds. This Mixture acts to either maintain the brightness level of the pulp at the target level or to increase the brightness level of the pulp. In addition the Mixture allows for maintaining the pulp at the target level of brightness even when the amounts of other ingredients, such as hydrogen peroxide, hydrosulfite, sodium silicate and magnesium, that are typically added to the pulp, are reduced.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 6, 2005
    Inventors: Sergey Shevchenko, Prasad Duggirala
  • Publication number: 20050194111
    Abstract: A method to enhance brightness in Chemical and Mechanical pulps comprising adding an organic sulfide chelant is described and claimed. A method to enhance delignification in a Chemical pulp comprising adding an organic sulfide chelant is also described and claimed.
    Type: Application
    Filed: May 3, 2005
    Publication date: September 8, 2005
    Inventors: Prasad Duggirala, Sergey Shevchenko, Kristine Salmen