Patents by Inventor Pieter Vonk

Pieter Vonk 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: 10369493
    Abstract: A continuous process for producing crystalline ammonium sulfate, said process comprising a start-up operation followed by a steady-state operation, wherein the start-up operation comprises: i) in a crystallizer, evaporating solvent from an approximately saturated ammonium sulfate solution; ii) replacing evaporated solvent with further approximately proximately saturated ammonium sulfate solution; iii) introducing to the crystallizer seed crystals of ammonium sulfate; iv) continuing to evaporate solvent, until a desired degree of supersaturation is reached; and v) recovering crystalline ammonium sulfate from ammonium sulfate solution in a recovery unit, and the steady-state operation comprises: vi) continuously feeding approximately saturated ammonium sulfate solution into the crystallizer and continuously withdrawing ammonium sulfate crystals from the crystallizer, such that the total combined volume of ammonium sulfate solution and ammonium sulfate crystals within the crystallizer remains constant; and vii)
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: August 6, 2019
    Assignee: CAP III B.V.
    Inventors: Geert Ekkelenkamp, Johan Thomas Tinge, Pieter Vonk
  • Patent number: 9676633
    Abstract: The invention relates to a process for preparing a crystalline ammonium sulfate product, which process comprises: a) subjecting in a crystallizer a feed solution of ammonium sulfate to crystallization to form a first slurry of ammonium sulfate crystals; b) subjecting the first slurry of ammonium sulfate crystals to a first size classification to yield a first coarse ammonium sulfate crystal fraction and a first fine ammonium sulfate crystal fraction; c) recycling at least part of the first fine ammonium sulfate crystal fraction to the feed solution of ammonium sulfate; and d) recovering a crystalline ammonium sulfate product from the first coarse ammonium sulfate crystal fraction, characterized in that: e) a second size classification is carried out on a second slurry of ammonium sulfate crystals to yield a second coarse ammonium sulfate crystal fraction and a second fine ammonium sulfate crystal fraction.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: June 13, 2017
    Assignee: CAP III B.V.
    Inventors: Geert Ekkelenkamp, Johan Thomas Tinge, Pieter Vonk
  • Publication number: 20150224421
    Abstract: A continuous process for producing crystal-line ammonium sulfate, said process comprising a start-up operation followed by a steady-state operation, wherein the start-up operation comprises: i) in a crystallizer, evaporating solvent from an approximately saturated ammonium sulfate solution; ii) replacing evaporated solvent with further approximately proximately saturated ammonium sulfate solution; iii) introducing to the crystallizer seed crystals of ammonium sulfate; iv) continuing to evaporate solvent, until a desired degree of supersaturation is reached; and v) recovering crystalline ammonium sulfate from ammonium sulfate solution in a recovery unit, and the steady-state operation comprises: vi) continuously feeding approximately saturated ammonium sulfate solution into the crystallizer and continuously withdrawing ammonium sulfate crystals from the crystallizer, such that the total combined volume of ammonium sulfate solution and ammonium sulfate crystals within the crystallizer remains constant; and vii)
    Type: Application
    Filed: August 28, 2013
    Publication date: August 13, 2015
    Inventors: Geert Ekkelenkamp, Johan Thomas Tinge, Pieter Vonk
  • Publication number: 20150218008
    Abstract: The invention relates to a process for preparing a crystalline ammonium sulfate product, which process comprises: a) subjecting in a crystallizer a feed solution of ammonium sulfate to crystallization to form a first slurry of ammonium sulfate crystals; b) subjecting the first slurry of ammonium sulfate crystals to a first size classification to yield a first coarse ammonium sulfate crystal fraction and a first fine ammonium sulfate crystal fraction; c) recycling at least part of the first fine ammonium sulfate crystal fraction to the feed solution of ammonium sulfate; and d) recovering a crystalline ammonium sulfate product from the first coarse ammonium sulfate crystal fraction, characterized in that: e) a second size classification is carried out on a second slurry of ammonium sulfate crystals to yield a second coarse ammonium sulfate crystal fraction and a second fine ammonium sulfate crystal fraction.
    Type: Application
    Filed: September 12, 2013
    Publication date: August 6, 2015
    Inventors: Geert Ekkelenkamp, Johan Thomas Tinge, Pieter Vonk
  • Publication number: 20070141971
    Abstract: A scalding apparatus for poultry is provided. In one embodiment, the apparatus includes an overhead conveyor for moving poultry, suspended by their legs, through an immersion tank filled with scald water. A filtering device and pumping unit can be used to withdraw the scald water, clean the scald water, and reintroduce the scald water to the tank. Upwardly directed nozzles, located in the bottom of the tank, provided a stream of scald water directed up and over the poultry. A reversing guide may be provided for redirecting the scald water downwards to the poultry. The immersion tank may be divided into chambers.
    Type: Application
    Filed: November 16, 2006
    Publication date: June 21, 2007
    Inventors: Leendert Aandewiel, Jacob Craaikamp, Jacob Kiewiet, Pieter Vonk
  • Publication number: 20070059525
    Abstract: The invention relates to a granular melamine, wherein the D99 lies between 300 ?m and 1800 ?m. The invention further relates to a process for compacting melamine comprising: a roll pressing step wherein a melamine powder is pressed into compacted melamine; a crushing step wherein the compacted melamine is crushed into granular melamine; a coarse screening step to which the granular melamine is supplied, wherein particles greater than a desired particle size are separated from the granular melamine, wherein the coarse screening step is carried out in such a fashion that the granular melamine has a D99 lying between 300 ?m and 1800 ?m.
    Type: Application
    Filed: June 3, 2004
    Publication date: March 15, 2007
    Inventors: Saskia Dijk Van, Pieter Vonk
  • Patent number: 5691290
    Abstract: A cleaning composition to remove unwanted paint, graffiti or other coatings from a substrate comprises 40-90 wt. % of a five-membered ring lactam, such as N-methyl-2-pyrrolidone, and 10-60 wt. % of a glycerol triester of a C1-C4 saturated aliphatic monocarboxylic acid. Additionally, up to 25 wt. % of the composition of diethylphthalate, diisopropyl adipate and/or a C1-C4 alkyl lactate may be present. Also a method of cleaning substrates and woven or non-woven tissue impregnated with the cleaning composition has been claimed.
    Type: Grant
    Filed: September 21, 1995
    Date of Patent: November 25, 1997
    Assignee: Unichema Chemie B.V.
    Inventors: Pieter Vonk, Anette Heymann