Patents by Inventor Torstein Obrestad

Torstein Obrestad 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: 11485689
    Abstract: The present disclosure concerns fertilizer particles comprising calcium nitrate and potassium nitrate. It is found that fertilizer particles comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate can be produced by melt granulation. Due to undercooling problems, such particles were not expected to be suitable for industrial production by melt granulation. However, the present disclosure provides a composition which forms a low viscosity melt with short solidification time. This was successfully achieved by reducing the water content of a fertilizer melt comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate to less than 3% w/w of the melt.
    Type: Grant
    Filed: January 15, 2018
    Date of Patent: November 1, 2022
    Assignee: YARA INTERNATIONAL ASA
    Inventors: Amund Myrstad, Petr Chladek, Torstein Obrestad
  • Publication number: 20220324763
    Abstract: The present disclosure concerns fertilizer particles comprising calcium nitrate and potassium nitrate. It is found that fertilizer particles comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate can be produced by melt granulation. Due to undercooling problems, such particles were not expected to be suitable for industrial production by melt granulation. However, the present disclosure provides a composition which forms a low viscosity melt with short solidification time. This was successfully achieved by reducing the water content of a fertilizer melt comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate to less than 3% w/w of the melt.
    Type: Application
    Filed: June 27, 2022
    Publication date: October 13, 2022
    Applicant: YARA INTERNATIONAL ASA
    Inventors: Amund MYRSTAD, Petr CHLADEK, Torstein OBRESTAD
  • Publication number: 20190389783
    Abstract: The present disclosure concerns fertilizer particles comprising calcium nitrate and potassium nitrate. It is found that fertilizer particles comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate can be produced by melt granulation. Due to undercooling problems, such particles were not expected to be suitable for industrial production by melt granulation. However, the present disclosure provides a composition which forms a low viscosity melt with short solidification time. This was successfully achieved by reducing the water content of a fertilizer melt comprising 43 to 47% w/w calcium nitrate and 46 to 54% w/w potassium nitrate to less than 3% w/w of the melt.
    Type: Application
    Filed: January 15, 2018
    Publication date: December 26, 2019
    Applicant: YARA INTERNATIONAL ASA
    Inventors: Amund MYRSTAD, Petr CHLADEK, Torstein OBRESTAD
  • Patent number: 10294170
    Abstract: The invention relates to a conditioning agent for reducing water absorption and dust formation of a particulate fertilizer, comprising 10 to 50 weight % of wax, 40 to 90 weight % of mineral oil and 1 to 15 weight % of a resin being mineral oil-soluble and miscible with wax and mineral oil, wherein the agent further comprises 0.1 to 1 weight % of a viscoelastic elastomer selected from the group of polyisobutylene and styrene-isoprene-styrene block copolymer which is soluble in mineral oil and has an average molecular weight of 30.000 to 5.000.000. The invention further relates to a particulate fertilizer composition, preferably a urea-ammonium sulfate (UAS) fertilizer, a urea fertilizer or a calcium nitrate fertilizer, comprising a particulate substrate, preferably an hygroscopic fertilizer, preferably a nitrogen-containing fertilizer, and 0.05 to 2 weight % of said coating thereon for reducing moisture uptake and dust formation of said fertilizer.
    Type: Grant
    Filed: November 25, 2015
    Date of Patent: May 21, 2019
    Assignee: YARA INTERNATIONAL ASA
    Inventors: Torstein Obrestad, Terje Tande
  • Patent number: 10118867
    Abstract: A single-step method for preparing a free-flowing, non-dusting micronutrient-coated particulate solid fertiliser material, the method comprising applying a single fluid onto particulate solid fertiliser material at ambient temperature without chemical reaction or chelation, said single fluid comprising a suspension of one or more micronutrient materials in an oil.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: November 6, 2018
    Assignee: Yara UK Limited
    Inventors: Stuart Charles Ward, Victoria Anne Butler, Torstein Obrestad, Terje Tande
  • Publication number: 20180201548
    Abstract: A single-step method for preparing a free-flowing, non-dusting micronutrient-coated particulate solid fertiliser material, the method comprising applying a single fluid onto particulate solid fertiliser material at ambient temperature without chemical reaction or chelation, said single fluid comprising a suspension of one or more micronutrient materials in an oil.
    Type: Application
    Filed: March 14, 2018
    Publication date: July 19, 2018
    Inventors: Stuart Charles Ward, Victoria Anne Butler, Torstein Obrestad, Terje Tande
  • Patent number: 9994492
    Abstract: A single-step method for preparing a free-flowing, non-dusting micronutrient-coated particulate solid fertilizer material, the method comprising applying a single fluid onto particulate solid fertiliser material at ambient temperature without chemical reaction or chelation, said single fluid comprising a suspension of one or more micronutrient materials in an oil.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: June 12, 2018
    Assignee: Yara UK Limited
    Inventors: Stuart Charles Ward, Victoria Anne Butler, Torstein Obrestad, Terje Tande
  • Patent number: 9932509
    Abstract: The present invention relates to the use of a double salt of Ca(NO3)2 and KNO3 for the manufacture of a melt, in particular a nitrate-based heat transfer fluid (HTF) and/or thermal energy storage fluid, for example in solar energy applications, such as in solar electrical power plant systems using a parabolic through, a central receiver or a linear Fresnel, which have both a low melting temperature and a high decomposition temperature, as well as to methods for the manufacture thereof. Using said double salt, a melt could be manufactured comprising at least NaNO3, KNO3 and Ca(NO3)2, preferably, an eutectic ternary melt comprising Ca(NO3)2, NaNO3 and KNO3 in a weight ratio of about 42:15:43 with an operating temperature of about 131° C. to about 560° C.
    Type: Grant
    Filed: September 17, 2013
    Date of Patent: April 3, 2018
    Assignee: YARA INTERNATIONAL ASA
    Inventors: Torstein Obrestad, Amund Myrstad, Tore Frogner
  • Patent number: 9908787
    Abstract: The invention relates to a method for producing an anhydrous powder having a calcium nitrate content of between 92 and 99.9 weight %, a water content of between 0.1 and 8 weight %; and a particle size of between 0.05 and 1.5 mm, wherein the method comprises the step of subjecting a calcium nitrate solution having a water content of between 70 and 15 weight % and a calcium nitrate content of between 30 and 85 weight % to a drying step in an industrial turbo-dryer, resulting in the anhydrous calcium nitrate powder. The invention furthermore relates to such an anhydrous calcium nitrate powder and the use of an industrial turbo-dryer to produce such anhydrous calcium nitrate powder.
    Type: Grant
    Filed: June 23, 2015
    Date of Patent: March 6, 2018
    Assignee: YARA INTERNATIONAL ASA
    Inventor: Torstein Obrestad
  • Publication number: 20170283339
    Abstract: The invention relates to a conditioning agent for reducing water absorption and dust formation of a particulate fertilizer, comprising 10 to 50 weight % of wax, 40 to 90 weight % of mineral oil and 1 to 15 weight % of a resin being mineral oil-soluble and miscible with wax and mineral oil, wherein the agent further comprises 0.1 to 1 weight % of a viscoelastic elastomer selected from the group of polyisobutylene and styrene-isoprene-styrene block copolymer which is soluble in mineral oil and has an average molecular weight of 30.000 to 5.000.000. The invention further relates to a particulate fertilizer composition, preferably a urea-ammonium sulfate (UAS) fertilizer, a urea fertilizer or a calcium nitrate fertilizer, comprising a particulate substrate, preferably an hygroscopic fertilizer, preferably a nitrogen-containing fertilizer, and 0.05 to 2 weight % of said coating thereon for reducing moisture uptake and dust formation of said fertilizer.
    Type: Application
    Filed: November 25, 2015
    Publication date: October 5, 2017
    Applicant: YARA INTERNATIONAL ASA
    Inventors: Torstein OBRESTAD, Terje TANDE
  • Publication number: 20170096347
    Abstract: The invention relates to a method for producing an anhydrous powder having a calcium nitrate content of between 92 and 99.9 weight %, a water content of between 0.1 and 8 weight %; and a particle size of between 0.05 and 1.5 mm, wherein the method comprises the step of subjecting a calcium nitrate solution having a water content of between 70 and 15 weight % and a calcium nitrate content of between 30 and 85 weight % to a drying step in an industrial turbo-dryer, resulting in the anhydrous calcium nitrate powder. The invention furthermore relates to such an anhydrous calcium nitrate powder and the use of an industrial turbo-dryer to produce such anhydrous calcium nitrate powder.
    Type: Application
    Filed: June 23, 2015
    Publication date: April 6, 2017
    Applicant: YARA INTERNATIONAL ASA
    Inventor: Torstein Obrestad
  • Publication number: 20150376076
    Abstract: A single-step method for preparing a free-flowing, non-dusting micronutrient-coated particulate solid fertiliser material, the method comprising applying a single fluid onto particulate solid fertiliser material at ambient temperature without chemical reaction or chelation, said single fluid comprising a suspension of one or more micronutrient materials in an oil.
    Type: Application
    Filed: February 20, 2014
    Publication date: December 31, 2015
    Applicant: YARA UK LIMITED
    Inventors: Stuart Charles Ward, Victoria Anne Butler, Torstein Obrestad, Terje Tande
  • Publication number: 20150344762
    Abstract: The present invention relates to the use of a double salt of Ca(NO3)2 and KNO3 for the manufacture of a melt, in particular a nitrate-based heat transfer fluid (HTF) and/or thermal energy storage fluid, for example in solar energy applications, such as in solar electrical power plant systems using a parabolic through, a central receiver or a linear Fresnel, which have both a low melting temperature and a high decomposition temperature, as well as to methods for the manufacture thereof. Using said double salt, a melt could be manufactured comprising at least NaNO3, KNO3 and Ca(NO3)2, preferably, an eutectic ternary melt comprising Ca(NO3)2, NaNO3 and KNO3 in a weight ratio of about 42:15:43 with an operating temperature of about 131° C. to about 560° C.
    Type: Application
    Filed: September 17, 2013
    Publication date: December 3, 2015
    Applicant: YARA INTERNATIONAL ASA
    Inventors: Torstein OBRESTAD, Amund MYRSTAD, Tore FROGNER
  • Patent number: 7500995
    Abstract: The invention concerns a method for the production of nitrate containing products (fertilizers, technical products) from undercooling melts, wherein a XN—water solution is evaporated up to a content of 50-99.8 weight % XN, where X is one or more selected from Ca, Mg, NH, Na and K, and N means nitrate. The preferred range of XN is 70-99.5 weight %. The melt is cooled down to and kept at a temperature at or below the crystallisation point and finely divided solid XN powder consisting of the equilibrium phases is added to the melt. Melt drops are then formed and allowed to cool and solidify during up to 70 seconds. It is preferred to use a cooling belt for solidification of the particles. The belt is cooled by air, water, oil or another medium.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: March 10, 2009
    Assignee: Yara International ASA
    Inventors: Jan Birger Isaksen, Lars Moland, Torstein Obrestad
  • Publication number: 20060013755
    Abstract: The invention concerns a method for the production of nitrate containing products (fertilizers, technical products) from undercooling melts, wherein a XN—water solution is evaporated up to a content of 50-99.8 weight % XN, where X is one or more selected from Ca, Mg, NH, Na and K, and N means nitrate. The preferred range of XN is 70-99.5 weight %. The melt is cooled down to and kept at a temperature at or below the crystallisation point and finely divided solid XN powder consisting of the equilibrium phases is added to the melt. Melt drops are then formed and allowed to cool and solidify during up to 70 seconds. It is preferred to use a cooling belt for solidification of the particles. The belt is cooled by air, water, oil or another medium.
    Type: Application
    Filed: November 1, 2002
    Publication date: January 19, 2006
    Inventors: Jan Isaksen, Lars Moland, Torstein Obrestad
  • Patent number: 6610267
    Abstract: The invention relates to a method for manufacturing a homogeneous and ammonium free calcium nitrate melt with high solidification temperature, suitable for conventional particulation methods, by mixing a potassium source with a calcium nitrate source and heating the formed mixture to 150-155° C. for forming a melt comprising 1.5-5.5% by weight of K (as KNO3), 13-18% by weight of water and 70-80% by weight of Ca(NO3)2. The invention further relates to homogeneous and ammonium free calcium nitrate particles where the particles are a particulated product from a melt comprising 1.5-5.5% by weight of K (as KNO3), 13-18% by weight of water and 70-80% by weight of Ca(NO3)2.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: August 26, 2003
    Assignee: Norsk Hydro ASA
    Inventors: Torstein Obrestad, Lars Gustav Moland
  • Patent number: 6176892
    Abstract: The invention relates to a method for making NK-fertilizers basically from calcium nitrate fertilizers and potassium nitrate and homogeneous NK-fertilizer products. Calcium nitrate fertilizer is melted together with potassium nitrate to form a melt or suspension thereof which is particulated to form a homogeneous NK-fertilizer. The calcium nitrate fertilizer and the potassium nitrate are melted at 90-120° C. and then heated to the desired particulation temperature being 160-190° C. for prilling and 90-140° C. for granulation. The components are mixed in ratios giving a melt or suspension comprising 40-14 weight % calcium nitrate, 55-85 weight % potassium nitrate, 0.5-6 weight % water, 0-4 weight % ammonium nitrate and 0-5 weight % magnesium nitrate.
    Type: Grant
    Filed: July 21, 1998
    Date of Patent: January 23, 2001
    Assignee: Norsk Hydro ASA
    Inventors: Torstein Obrestad, Jan Birger Isaksen, Lars Gustav Moland
  • Patent number: 6171358
    Abstract: Homogeneous calcium nitrate based fertilizers containing sulphur, and method for their preparations. Solid gypsum and/or a slow reacting sulphate mineral is mixed with melted calcium nitrate fertilizer at a temperature of 90-110° C. and kept at this temperature for 3-15 minutes and subsequently particulated at a temperature of 80-110° C. The particulation by prilling is preformed at 95-110 ° C. and the particulation by granulation is performed at 90-110° C. The fertilizer is a homogeneous composition of a calcium nitrate fertilizer and gypsum and/or a slow reacting sulphate mineral comprising 0.1-5.0 weight % SO4—S, 14-19 weight % water soluble calcium and 16-21 weight % total calcium, and 0-3.0 weight % water soluble magnesium. The fertilizer may contain microamounts of Se and/or Co. and/or micronutrients like Mn, Cu, B and Zn.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: January 9, 2001
    Assignee: Norsk Hydro ASA
    Inventors: Torstein Obrestad, Johanne Rødsvik, Torbjørn Legard
  • Patent number: 5603745
    Abstract: The invention relates to an agricultural composition and a conditioning agent. The agricultural composition comprises a substrate, being a nitrate-containing fertilizer, and 0.1-2 weight % of a coating comprising 10-50 weight % wax, 90-40 weight % oil and 1-30 weight % resin being oil-soluble and miscible with wax. The conditioning agent is useful for reducing hygroscopicity and dust formation of fertilizers. It comprises 10-50 weight % wax, 90-40 weight % oil and 1-30 weight % oil being oil soluble and miscible with wax. When applied for nitrate of lime, this agent comprises preferably 15-30 weight % wax, 70-85 weight % white oil and/or vegetable oil and/or refined mineral oil and 2-15 weight % resin, which comprises non-crystalline tall oil resin and/or esters of stabilized resin acids.
    Type: Grant
    Filed: June 23, 1995
    Date of Patent: February 18, 1997
    Assignee: Norsk Hydro a.s
    Inventors: Jarl M. Pettersen, Torstein Obrestad, Susanne G. Snartland
  • Patent number: 5472530
    Abstract: The present invention relates to a method of manufacturing free-flowing ammonium nitrate particles, applying an inorganic coating. The invention also comprises an anti-caking coating.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: December 5, 1995
    Assignee: Norsk Hydro a.s
    Inventors: Torstein Obrestad, Leif G. Helleb.0., Jan B. Isaksen, Bj.0.rn Juliussen