Flames Combustion Patents (Class 162/31)
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Patent number: 10472267Abstract: A salt separator separates salts and/or solid materials from a pumpable aqueous fluid mixture under process conditions, which lie in the range of the critical point for the fluid mixture. The salt separator contains a reaction zone in a cavity for transforming the pumpable aqueous fluid mixture into a raw mixture, e.g. a methanation reaction, and a feed opening for the pumpable aqueous fluid mixture to the cavity. The feed opening is realized in a rising pipe that protrudes into the cavity. A first extraction opening is provided for the raw mixture freed of salts and/or solid materials. The first extraction opening is arranged in the upper region of the cavity and a second extraction opening is provided for a brine containing the salt and/or the solid materials. The second extraction opening is arranged in the lower region of the cavity and is located lower down than the feed opening.Type: GrantFiled: March 2, 2015Date of Patent: November 12, 2019Assignee: Paul Scherrer InstituteInventors: Gaël Peng, Joachim Reimer, Frédéric Vogel, Hemma Zoehrer, Erich De Boni
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Patent number: 10143716Abstract: There is provided a process for making a composition suitable for topical application comprising the steps of a) heating at least one fruit and/or vegetable pulp to up to a temperature in the range of about 40° C. to 100° C.; b) mixing between 1 and 40% w/w of a mild base with the heated fruit and/or vegetable pulp. There is also provided a fruit and/or vegetable derived composition suitable for topical application prepared by the above process. There is further provided a fruit and/or vegetable derived composition comprising at least one fruit and/or vegetable-derived pulp and a mild base, said composition having a pH in the range of about 7.5 to about 9.5.Type: GrantFiled: February 12, 2014Date of Patent: December 4, 2018Assignee: PHOENIX EAGLE COMPANY PTY LTDInventor: Thomas James McArthur
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Patent number: 10023512Abstract: Methods of producing organic materials, and in particular methods of producing petroleum materials and organic compounds such as aromatic acids, phenols, and aliphatic poly-carboxylic acids using an oxidative hydrothermal dissolution (OHD) process are disclosed.Type: GrantFiled: June 4, 2012Date of Patent: July 17, 2018Assignee: SOUTHERN ILLINOIS UNIVERSITY CARBONDALEInventors: Kenneth B. Anderson, John C. Crelling, William W. Huggett, Derek M. Perry
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Patent number: 8764937Abstract: A method and apparatus for conversion of paper residue into a mineral product uses a fluidized bed device with a distribution plate for securing an even distribution and supply of at least combustion air to the bed material and to the paper residue. An air box below the distribution plate supplies combustion air to the bed material and paper residue above the distribution plate. A heat exchanging section receives in separate parts ambient air and flue gases from the fluidized bed device for exchanging heat between flue gases and ambient air. The heat exchanging section is connected to the air box for supplying the heated ambient air to the air box for use as combustion air. A control system is employed for controlling the amount of bed material and the dimension of its particles and is arranged to monitor and maintain a process parameter within a predefined range.Type: GrantFiled: September 26, 2012Date of Patent: July 1, 2014Assignee: Voith Patent GmbHInventor: Joseph Jan Peter Biermann
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Patent number: 8640634Abstract: An arrangement is disclosed for supplying an air jet form to the furnace of a recovery boiler, where the furnace has a front wall, a rear wall and side walls. Black liquor spraying devices are disposed on the furnace walls on one or several levels of the furnace. A plurality of air ports are located at several horizontal elevations for introducing air into the furnace from an air supply. In the arrangement for the secondary air flows, at least two horizontal air levels at different elevations are arranged above the lower primary levels and below the black liquor sprayer. Secondary air is supplied from two opposite walls. The secondary air ports on each of said first and second horizontal elevations comprise air ports for each horizontal elevation that project a pattern of large air jets into the furnace from said opposite walls and said secondary air ports further comprise a plurality of secondary air ports on at least one of the elevations that project smaller air jets into the furnace.Type: GrantFiled: October 14, 2005Date of Patent: February 4, 2014Assignee: Andritz OyInventors: Kari Saviharju, Jorma Simonen, Raimo Paju, Jukka Savolainen, Esa Vihavainen
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Patent number: 8607718Abstract: A combustion air system particularly useful for Kraft process recovery boilers or soda process recovery boilers has a level of liquor air ports located above the black liquor guns, and multiple levels of tertiary air formed by substantially vertically aligned tertiary air ports located above the black liquor guns. The liquor air ports and the tertiary air ports are on the same opposing walls of the furnace and are substantially vertically aligned with air ports in the same wall at different levels. The liquor air ports are located just above the black liquor guns, within a range of about ½ foot to about four feet. The tertiary air ports are laterally offset with respect to the tertiary air ports on the opposing wall of the furnace.Type: GrantFiled: March 30, 2007Date of Patent: December 17, 2013Assignee: Babcock & Wilcox Power Generation Group, Inc.Inventor: Richard A. Wessel
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Patent number: 8500954Abstract: The invention relates to a method and apparatus for processing the black liquor of a pulp mill to recover the chemicals and energy therein. In the invention, the black liquor is pyrolyzed in a pyrolysis reactor (6), formed gaseous components are lead for utilization, sand is returned to a fluidized-bed boiler, and solid matter is mixed with water, whereby a soda-water solution is returned to the pulping process and solid carbon to the fluidized-bed boiler (1).Type: GrantFiled: October 1, 2010Date of Patent: August 6, 2013Assignee: Metso Power OYInventors: Jani Lehto, Kari Kuukkanen, Erkki Välimäki
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Patent number: 8246779Abstract: Methods and apparatus for maintaining sulfur concentration in the chemical recovery cycle of a Kraft pulping process. A portion of the recovery boiler ash is dissolved, treated to remove solids, and combined with an acid to provide a solution. The recovery boiler ash may be dissolved directly in the acid. The acid may be effluent from a chlorine dioxide generator. The resulting solution is maintained in a fully dissolved state and subjected to an acid separation step to provide a sodium sulfate enriched phase, which may be used to maintain sulfur concentration in the Kraft pulping process, and a sulfuric acid phase. Chlorine ions can be separated with the sulfuric acid phase. The sulfuric acid phase can be recycled to the chlorine dioxide generator.Type: GrantFiled: September 24, 2010Date of Patent: August 21, 2012Assignee: NORAM Engineering and Constructors Ltd.Inventors: Jonathan Edward Foan, James Theodore Wearing
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Patent number: 7988820Abstract: An apparatus for cleaning and cooling a liquor nozzle, the nozzle including at least a liquor tube for feeding liquor and chemicals into a furnace of a recovery boiler. The apparatus includes an outer casing tube, which defines a space whereto conduits are provided for introducing water and steam to generate an emulsion or a conduit for introducing emulsion generated by the water and steam and the surface of which is provided with openings, such as pores or holes, for discharging the emulsion formed by water and steam through the outer casing.Type: GrantFiled: July 2, 2008Date of Patent: August 2, 2011Assignee: Andritz OyInventors: Markku Tanttu, Kari Saviharju, Sirpa Du Jardin
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Patent number: 7553394Abstract: In the process for producing kraft pulp, performing a potassium ion removal step of flowing an aqueous solution containing ashes recovered from a combustion exhaust gas generated in a black solution combustion step by a dust collector through a packed bed filled with a sodium-type cation exchange organic resin to adsorb and remove potassium ions contained in the aqueous solution; and a regeneration step of treating the cation exchange organic resin used in the potassium ion removal step with a solution consisting essentially of aqueous sodium hydroxide to regenerate the cation exchange resin, where a fraction recovered from the potassium ion removal step which is rich in sodium sulfate and sodium carbonate is recycled to the black solution concentrating step, and a sodium hydroxide effluent recovered from the regeneration step is recycled to a bleaching step and used in a bleaching process.Type: GrantFiled: September 11, 2003Date of Patent: June 30, 2009Assignees: Nippon Rensui Co., Hokuetsu Paper Mills, Ltd.Inventors: Saburo Furusho, Norio Kawano, Shigeru Wakamoto
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Patent number: 7207280Abstract: An arrangement is disclosed for supplying an air jet form to the furnace of a recovery boiler, where the furnace has a front wall, a rear wall and side walls. Black liquor spraying devices are disposed on the furnace walls at one or several levels of the furnace. A plurality of air ports are located at several horizontal levels for introducing air into the furnace from an air supply. In the arrangement for the secondary air flows, two horizontal air levels at different elevations are arranged above the lower primary levels and below the black liquor sprayer. Secondary air is supplied from two opposite walls and the air ports from each of the two levels are located so that the air jets are introduced in an interlaced pattern having an even number of jets on one opposite wall and an uneven number of jets on the other opposite wall. The air jets of said at least two air levels are located substantially one above each other in substantially vertical rows.Type: GrantFiled: December 30, 2003Date of Patent: April 24, 2007Assignee: Andritz OyInventors: Kari Saviharju, Jorma Simonen, Liisa Simonen, Esa Vakkilainen, Esko Mattelmaki
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Publication number: 20040011484Abstract: A method to produce energy at a pulp mill, including the steps of: combusting pulping process waste liquor in the furnace of a recovery boiler to generate flue gases, recovering the heat from the flue gases by producing saturated and/or partially superheated steam in the recovery boiler, gasifying wood, bark or wood wastes in a gasifier for producing a combustible gas, burning at least part of the combustible gas in a superheating boiler, and superheating the saturated and partially superheated steam in the superheating boiler to produce superheated steam.Type: ApplicationFiled: April 25, 2003Publication date: January 22, 2004Applicant: Andritz Oy, Helsinki, FinlandInventors: Kari Saviharju, Jorma Simonen, Olli Arpalahti, Lasse Koivisto
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Patent number: 6500301Abstract: Arrangement for understoichiometric gasification of spent liquor from chemical pulp production, comprising an upper reactor part (2), which upper reactor part is provided with a burner (5) for the spent liquor and with an internally clad reactor jacket (4), and lower separating part (8) for separating a phase of solid and/or molten material, formed on gasification, from a phase of combustible gaseous material. According to the invention, at least the upper reactor part (2), with its clad reactor jacket, is surrounded by an outer vessel (1), with a gap (13) being present between the reactor jacket (4) and the outer vessel (1). Connected to the said gap (13) there are one or more inlets (14) and at least one outlet (21) for a coolant medium.Type: GrantFiled: November 6, 2001Date of Patent: December 31, 2002Assignee: Chemrec AktiebolagInventor: Bengt Nilsson
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Patent number: 6425976Abstract: The invention refers to a method for black liquor gasification in recovery boilers, of the type having a lower portion, referred to as a lower furnace and an upper portion, referred to as an upper furnace, black liquor sprayers for introduction of black liquor provided in the boiler above the lower furnace, and a number of combustion air levels, whereby the invention incorporates adding oxygen enriched air to the combustion air or directly into the lower furnace at at least one air level underneath the liquor sprayers for the purpose of creating the best possible reducing conditions in the lower furnace, redistributing from the lower furnace combustion air not needed therein following the addition of oxygen enriched air, thereby significantly reducing upward gas velocity underneath the black liquor sprayers, and introducing the redistributed combustion air in the upper furnace, thereby creating the reducing conditions and a controlled temperature in the lower furnace for emission control.Type: GrantFiled: April 16, 2001Date of Patent: July 30, 2002Assignee: AGA ABInventors: Kent K Sandquist, Anders Kullendorff
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Patent number: 6408771Abstract: Methods are presented to increase the throughput of a recovery boiler equipped with at least primary and secondary levels of injection of air. The methods comprise operating the recovery boiler with a third level of oxidant injection below or at the same level as the secondary level, and oxygen enrichment applied to at least the secondary level and said third level.Type: GrantFiled: September 9, 1999Date of Patent: June 25, 2002Assignees: Air Liquide America Corporation, American Air Liquide, L'Air Liquide Societe Anonyme pour l'Etude et, l'Exploitation des Procedes Georges Claude, Jansen Combustion and Boiler Technologies, Inc.Inventors: Louis C. Philippe, Eric L. Duchateau, David R. Scheeff, Arie Verloop, Edward C. Dye
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Publication number: 20020059995Abstract: The invention refers to a method for black liquor gasification in recovery boilers, of the type having a lower portion, referred to as a lower furnace and an upper portion, referred to as an upper furnace, black liquor sprayers for introduction of black liquor provided in the boiler above the lower furnace, and a number of combustion air levels, whereby the invention incorporates adding oxygen enriched air to the combustion air or directly into the lower furnace at at least one air level underneath the liquor sprayers for the purpose of creating the best possible reducing conditions in the lower furnace, redistributing from the lower furnace combustion air not needed therein following said addition of oxygen enriched air, thereby significantly reducing upward gas velocity underneath the black liquor sprayers, and introducing said redistributed combustion air in the upper furnace, thereby creating the reducing conditions and a controlled temperature in the lower furnace for emission control.Type: ApplicationFiled: April 16, 2001Publication date: May 23, 2002Inventors: Kent K. Sandquist, Anders Kullendorff
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Publication number: 20010023750Abstract: The present invention relates to a method and an arrangement for use in connection with the combustion of black liquor. In the method the black liquor is concentrated in a multi-effect evaporation plant in order to obtain black liquor at a suitable dry-solids content for combustion and to generate vapor. The concentrated black liquor is taken to be combusted in a recovery boiler, into which combustion air is fed at several levels for the combustion process. It is a characteristic feature of the invention that the air fed to at least one air level is preheated by using vapor generated in the concentration of the black liquor as heat source.Type: ApplicationFiled: March 19, 2001Publication date: September 27, 2001Inventor: Petri Tikka
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Patent number: 6287415Abstract: Arrangement in a soda recovery boiler, comprising normal melt chutes (6) for removing molten salt from the recovery boiler (1). The recovery boiler (1) comprises an outlet (8), mounted in the wall of the recovery boiler such that it is situated lower down than the normal melt chutes (6), in which case the molten salt can be removed from the bottom of the recovery boiler substantially through the outlet (8), when the recovery boiler (1) is emptied for maintenance or the like.Type: GrantFiled: August 31, 2000Date of Patent: September 11, 2001Assignee: Kvaerner Pulping OyInventors: Kalle Salmi, Jaakko Mäkelä, Aki Hakulinen, Tuomo Ruohola
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Patent number: 6228214Abstract: The invention refers to a method for black liquor gasification in recovery boilers, of the type having a lower portion, referred to as a lower furnace and an upper portion, referred to as an upper furnace, black liquor sprayers for introduction of black liquor provided in the boiler above the lower furnace, and a number of combustion air levels, whereby the invention incorporates adding oxygen enriched air to the combustion air or directly into the lower furnace at at least one air level underneath the liquor sprayers for the purpose of creating the best possible reducing conditions in the lower furnace, redistributing from the lower furnace combustion air not needed therein following the addition of oxygen enriched air, thereby significantly reducing upward gas velocity underneath the black liquor sprayers, and introducing the redistributed combustion air in the upper furnace, thereby creating the reducing conditions and a controlled temperature in the lower furnace for emission control.Type: GrantFiled: October 12, 1999Date of Patent: May 8, 2001Assignee: AGA ABInventors: Kent K Sandquist, Anders Kullendorff
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Patent number: 6186080Abstract: A boiler recovers a soda component from pulp spent liquor and is able to prevent carry-over of unburnt char and deformation of a char bed configuration and to attain a stable combustion with low NOx generation. By regulating the combustion air supply, and feeding inert gas along a furnace side wall around the char bed, there are formed a combustion zone of reduction atmospheric field where air ratio in the surroundings of the char bed is 0.8 or less, a combustion zone of reduction atmospheric field where air ratio is 1.0 or less and unburnt components exist (including the case of a reduction atmospheric field where air ratio is 1.0 or less and unburnt components exist with the two combustion zones being combined together) and a combustion zone where combustion is completed.Type: GrantFiled: November 6, 1997Date of Patent: February 13, 2001Assignee: Mitsubishi Heavy Industries, Ltd.Inventors: Hirokazu Hino, Toshimitsu Ichinose, Kimishiro Tokuda, Yoshihisa Arakawa, Masaaki Nagai, Yoshitaka Baba
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Patent number: 6183598Abstract: The invention relates to a process for recovering alkali and heat from a black liquor (5) containing silicate from a soda cook of e.g. grass, reed, straw and bagasse. In the process the black liquor (5) is treated with a gas (6) containing carbon dioxide to precipitate silica and lignin, the precipitate (9) is separated (2) from the black liquor, which is evaporated (3) and burnt (4) to generate heat and to recover a sodium carbonate melt. In the invention the black liquor (5) containing silicate is neutralised with a surplus of the gas (6) containing carbon dioxide, which preferably contains over 60% by volume of carbon dioxide. The evaporation (3) of black liquor mainly takes place after the precipitate (9) rich in silica has been separated (2).Type: GrantFiled: October 1, 1998Date of Patent: February 6, 2001Assignee: Jaako Poyry OyInventor: Bertel Myreen
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Patent number: 6168685Abstract: Concentrated black liquor formed in a kraft pulp mill process is treated to effect exothermal oxidation of black liquor solids, so as to heat the concentrated black liquor and consume a proportion of the black liquor solids. Such procedure eliminates the need to use steam to preheat black liquor and decreases the overall heating value of the concentrated black liquor, allowing an increased black liquor recovery boiler capacity to be achieved.Type: GrantFiled: October 14, 1994Date of Patent: January 2, 2001Assignee: Praxair Canada Inc.Inventor: Chris Ka Kee Ho
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Patent number: 6155210Abstract: The invention relates to a method of firing black liquor in recovery boilers where the intention is to get fumes having a low content of nitrogen oxides (NO.sub.x). The invention is characterized in that a part of the combustion air is added as a last portion at a level on a very high level so that a reducing atmosphere will exist in a very great part of the boiler and during a long period of time of at least 3-5 seconds. The invention also includes a recovery boiler for carrying out the above said method.Type: GrantFiled: July 19, 1999Date of Patent: December 5, 2000Assignee: Kvaerner Pulping ABInventor: Nils Gustav Lindman
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Patent number: 6071377Abstract: The invention relates to a process for combusting black liquor in recovery boilers where the intention is to obtain flue gases which have a low content of nitrogen oxides (NO.sub.x). The invention is characterized in that ammonia is supplied to a part of the combustion air, which part is then supplied to the recovery boiler, as the final portion, at a high level, so that a reducing atmosphere is created in a very large part of the recovery boiler and for a long time, of at least 2.5-5 seconds or more. The invention also includes a recovery boiler for implementing the above mentioned process.Type: GrantFiled: June 4, 1998Date of Patent: June 6, 2000Assignee: Kvaerner Pulping ABInventor: Nils Gustav Lindman
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Patent number: 6030493Abstract: Provided is a process for recovering chemicals and energy from spent liquor obtained when producing paper pulp by chemical delignificatation of fibrous raw material. The spent liquor is gasified in at least two reactors, a first and a second stream of solid and/or smelt material and of combustible gaseous material being formed. The formed material is treated in one or more devices (5, 6, 7, 8), whereby a first (9) and a second liquor (27) are formed. The pressure and/or temperature in the first reactor differ(s) from the pressure and/or temperature in the second reactor. In addition, one or more process chemicals are recovered selectively from the formed liquor and/or gas, and are thereafter returned in whole or in part to one or more of the reactors (1, 2) and/or to one or more of the devices (5, 6, 7, 8) for treatment of the formed material.Type: GrantFiled: May 2, 1997Date of Patent: February 29, 2000Assignee: Kvaerner Pulping, ABInventor: Bengt Nilsson
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Patent number: 6027609Abstract: A Pulp Mill Recovery installation for producing liquors containing different concentrations of recovered process chemicals or combustion gasses containing different concentrations of process chemicals from a spent liquor obtained from the production of pulp.Type: GrantFiled: May 2, 1997Date of Patent: February 22, 2000Assignee: Kvaener Pulping ABInventor: Bengt Nilsson
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Patent number: 5992337Abstract: Methods of increasing the throughput of recovery boilers equipped with at least two levels of injection of air, the methods improving the thermal efficiency of the boiler with oxygen enrichment of the air in at least one level of the combustion air system, at or above the secondary air level. In one method, a black liquor recover boiler having two levels of air injection is retrofitted with a third level of oxidant injection below or at the same level as the original secondary air, and oxygen enrichment is applied to at least the original secondary air stream and the third level air stream. A preferred method is for the third level to be placed at or close to the same level as the black liquor injector ports.Type: GrantFiled: September 26, 1997Date of Patent: November 30, 1999Assignees: Air Liquide America Corporation, American Air Liquide, Inc., l'Air Liquide, Societe Anonyme Pour l'Etude et, l'Exploitation des Procedes Georges Claude, Jansen Combustion and Boiler Technologies, Inc.Inventors: Louis C. Philippe, Eric L. Duchateau, David R. Scheeff, Arie Verloop, Edward C. Dye
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Patent number: 5989387Abstract: A method for adjusting the chlorine equilibrium in a sulphate cellulose process, wherein part of the chlorine contained in the cycle is separated and removed. In the method, strong odour gases from the sulphate cellulose process are introduced into a soda recovery boiler for burning so that chlorine contained in the liquor is in the form of hydrogen chloride (HCl) in the upper part of the soda recovery boiler and can subsequently be separated from the flue gases in a flue gas scrubber. The chlorine equilibrium is adjusted by removing part of the chlorine-containing washing solution.Type: GrantFiled: January 17, 1996Date of Patent: November 23, 1999Assignee: Tampella Power OyInventors: Paavo Hyoty, Risto Hamalainen, Maiju Alaniemi, Keijo Imelainen, Pauli Harila, Veli-Antti Kivilinna, Ahti Klami
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Patent number: 5976318Abstract: A method for burning secondary sludge in a recovery boiler, in which method secondary sludge is mixed with black liquor. According to the method, an alkali is added to the secondary sludge so as to obtain a mixture having a pH of over 7, whereafter the mixture of alkali and secondary sludge is heated to a temperature of over 80.degree. C. and kept at this temperature for over 30 minutes. Thereafter the heat treated mixture of alkali and secondary sludge is supplied to the thick end of a black liquor evaporation plant.Type: GrantFiled: January 15, 1998Date of Patent: November 2, 1999Assignee: Tampella Power OyInventors: Matti Knuutila, Jarmo Kaila, Jukka Vaistomaa, Keijo Imelainen, Pauli Harila, Veli-Antti Kivilinna, Ahti Klami
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Patent number: 5814189Abstract: Provided is a novel process for the preparation of an aqueous solution of alkaline compounds from a generator gas, containing carbon monoxide, carbon dioxide, hydrogen and entrained alkaline compounds, which gas has been formed during partial combustion of cellulose spent liquors in a gas generator connected to a quench vessel.Type: GrantFiled: February 3, 1997Date of Patent: September 29, 1998Assignee: Kvaerner Pulping ABInventors: Lars Stigsson, Nils Bernard
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Patent number: 5746886Abstract: The present invention relates to a method for producing pulp cooked under alkaline conditions, in which method cellulose-containing material is brought into contact, in a digester, with an alkaline cooking liquor containing dissolved potassium and sodium compounds, with used spent cooking liquor being separated off from the cellulose-containing material and withdrawn for the recovery of energy and chemicals, wherein:a) The molar ratio, calculated as K/K+Na, between potassium and sodium in a withdrawn spent cooking liquor exceeds 0.25.b) The withdrawn spent cooking liquor is concentrated with respect to its content of solid material and is subjected to partial oxidation in a reactor, resulting in the formation of a, combustible gas which is withdrawn from the reactor.c) oxygen-containing gas is supplied to the reactor in order to support the partial oxidation.d) The operating temperature in the reactor is adjusted to between 400.degree.-1200.degree. C.Type: GrantFiled: July 14, 1995Date of Patent: May 5, 1998Assignee: Kvaerner Pulping ABInventors: .ANG.ke Backlund, Lars Stigsson
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Patent number: 5707490Abstract: A method of recovering energy from waste liquors from cellulose pulp processes produces high quality superheated steam, a savings in material costs is achieved, and the utilization factor of the pulp mill is improved (that is the number of shutdowns for service is reduced). A main stream of waste liquor from cellulose pulp processing is divided into first and second streams. The first stream is combusted in the recovery boiler to produce steam and the steam is fed to a superheating boiler. The second stream of waste liquor is gasified outside the recovery boiler to produce a combustible gas and an inorganic fraction. The inorganic fraction is not fed to the recovery boiler, but is separately recovered. The combustible gas is burned in the superheating boiler to superheat steam produced from combusting the first stream of waste liquor, the combustible gas providing substantially the only source of fuel for superheating the steam in the superheating boiler.Type: GrantFiled: April 18, 1996Date of Patent: January 13, 1998Assignee: Ahlstrom Machinery OyInventors: Marjo Kuusio, Samuli Nikkanen
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Patent number: 5683550Abstract: A method and system for treating waste liquors from pulping processes for recovering energy and chemicals from the waste liquors (such as kraft black liquor). A recovery boiler having a furnace for combusting waste liquor includes a plurality of injection nozzles in the furnace walls, for injecting waste liquor into the furnace. At least one conduit is disposed in at least one wall of the furnace below the nozzles for withdrawing a portion of the combustible gas from the furnace. Typically between about 10-50% of the combustible gas produced in the furnace is withdrawn through the conduit or conduits below the nozzles, and the withdrawn gas is cooled and purified. The system may utilize a superheater which is separate and distinct from the recovery boiler, the cleaned and cooled withdrawn gas led to the separate superheater.Type: GrantFiled: February 5, 1996Date of Patent: November 4, 1997Assignee: Ahlstrom Recovery Inc.Inventor: Rolf C. Ryham
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Patent number: 5672246Abstract: Waste liquor from cellulose pulp processes is used in a recovery boiler to recover energy and chemicals. The recovery boiler includes a furnace section in which heat and exhaust gases are generated, and heat recovery surfaces downstream of the furnace section in a path of exhaust gas movement. Waste liquor is injected into the furnace section of the recovery boiler at a first location, and the exhaust gases produced are divided into at least first and second streams. The first stream is passed into association with the heat recovery surfaces of the recovery boiler and then discharged, while the second stream is withdrawn from the recovery boiler at a second location between the first location and the heat recovery surfaces. The withdrawn second stream is positively cooled exteriorly of the recovery boiler preferably utilizing a circulating bed cooler.Type: GrantFiled: April 1, 1996Date of Patent: September 30, 1997Assignee: Ahlstrom Machinery OyInventor: Keijo Raak
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Patent number: 5660685Abstract: A method of preparing a digesting liquor having high sulphidity from a spent liquor obtained from digesting cellulosic fiber material, optionally without a conventional causticizing step is provided. Thermal decomposition of the spent liquor is conducted under reducing conditions in a reactor at a pressure of from atmospheric pressure up to about 150 bar and at a temperature of about 500.degree. to 1600.degree. C. so that a combustible gas phase containing hydrogen sulphide is formed in the reactor and extracted therefrom, and a phase of solid or molten material of substantially sodium sulphide or potassium sulphide, or mixtures thereof. The solid or molten material is dissolved in an aqueous liquid to produce said digesting liquor. The invention hydrogen sulphide is recovered from the gas phase and returned to the reactor to be present during the thermal decomposition of the spent liquor.Type: GrantFiled: November 21, 1994Date of Patent: August 26, 1997Assignee: Chemrec AktiebolagInventor: Bengt Nilsson
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Patent number: 5637192Abstract: Resonant tubes of a pulse combustor are immersed in a bed of solid particles in a reaction zone to provide indirect heat from the pulsating combustion gases to the solid particles of the bed. The bed is maintained in an agitated state by a gas or vapor flowing through the bed. Reactant materials are introduced into the agitated bed and undergo reaction at enhanced rates resulting from heat transfer coefficients at least about twice as high as those of steady flow combustors and an intense acoustic pressure level propagated from the pulsating combustor into the reaction zone. The apparatus is useful, for example, to steam reform heavy hydrocarbons and to gasify carbonaceous material, including biomass and black liquor to produce combustible gas at relatively low temperatures, with steam being utilized as the bed fluidizing medium. Black liquor gasification, utilizing sodium carbonate as bed solids, results in liquor energy and chemical content recovery without smelt production.Type: GrantFiled: May 11, 1995Date of Patent: June 10, 1997Assignee: Manufacturing and Technology Conversion InternationalInventors: Momtaz N. Mansour, Kanda-Swamy Durai-Swamy, David W. Warren
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Patent number: 5632858Abstract: A system for providing heated fluidized bed gasification of a residual waste liquor provides a bed of granular material and a source of liquor provided to the material bed. An injector is situated in the material bed and communicates with an air source, a fuel source and a steam source. Fuel and air are combusted in the injector and mixed with the steam which forms a combustion product and steam mixture which is in turn injected into the material bed. The combustion and mixing is separated from the bed material by being confined within the injector. The injector is a bubble cap having at least one hole or an injector made of a porous ceramic material.Type: GrantFiled: April 11, 1995Date of Patent: May 27, 1997Assignee: The Babcock & Wilcox CompanyInventor: John B. Kitto, Jr.
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Patent number: 5603803Abstract: A method and apparatus for use in the pulp industry for recovering heat in the spent liquor recovery boiler, whereby the boiler walls are formed of water-cooled tubes connected to the water/steam circulation system of the boiler. The lower section of the boiler is defined by water tubes connected to a separate water circulation system of a forced type. Thus, heat is preferably recovered in the lower section of the boiler by a separate water circulation system having a lower pressure than in the water/steam circulation system of the boiler.Type: GrantFiled: April 13, 1995Date of Patent: February 18, 1997Assignee: Ahlstrom Machinery CorporationInventor: Keijo Raak
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Patent number: 5562804Abstract: A method for adjusting the sulphur/sodium ratio in a soda recovery boiler when strong sulphurous odour gases are burned therein. According to the method, sodium is introduced into the soda recovery boiler in an amount proportional to the amount of sulphur either as sodium hydroxide, sodium carbonate compounds or soap, whereby the sodium and sulphur react, forming sodium sulphate, which can be removed from the flue gases together with fly ash.Type: GrantFiled: July 21, 1994Date of Patent: October 8, 1996Assignee: Tampella Power OyInventors: Seppo Tuominiemi, Esa Pikkujamsa, Keijo Imelainen, Pauli Harila, Veli-Antti Kivilinna, Ahti Klami
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Patent number: 5549788Abstract: Effluents are minimized from a cellulose pulp mill having a recovery boiler by concentrating liquid effluents from the bleach plant and/or liquid spills from process streams, incinerating the concentrated effluents in the recovery boiler, removing particles present in the flue gases from the recovery boiler to produce an ash including salts containing potassium and chloride, and sulfur compounds, and removing the potassium and chloride from the ash while returning the sulfur containing compounds to the recovery loop, so as to balance the sulfur, chloride and potassium levels in the mill. The sulfur is typically returned directly to a stream of black liquor just before entry into the recovery boiler. Green liquor is produced from the melt, which preferably is treated to remove metals from it prior to caustization (e.g. by sedimentation and/or filtration), and prior to green liquor crystallization to produce sodium hydroxide.Type: GrantFiled: August 31, 1993Date of Patent: August 27, 1996Assignee: A. Ahlstrom CorporationInventors: Tuomo S. Nykanen, Brian F. Greenwood, Johan Gullichsen, Erkki Kiiskila, Esko Mattelmaki, Joseph R. Phillips, Jan T. Richardsen, Rolf Ryham, Jarmo Soderman, Karl G. Wiklund
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Patent number: 5547543Abstract: Apparatus for a pulp and paper mill, and methods of acting on liquid effluents produced in the mill, which minimizes the discharge of polluting gaseous and liquid effluents to the environment. Liquid effluents from the bleach plant are concentrated (e.g. evaporated), incinerated (e.g. gasified), leached, crystallized (e.g. freeze crystallized) then washed, and then fed to the plant chemical recovery loop. White liquor produced from the recovery boiler melt is fully oxidized and used in place of caustic in the bleach plant. Essentially all sulfuric acid, sulfur dioxide, caustic, and chlorine dioxide necessary for the pulp mill is produced from mill liquid effluents and gas waste streams, on site at the pulp mill. Typical bleaching sequences that can be used are DE.sub.op D.sub.n D, or AZE.sub.o PZP.Type: GrantFiled: July 12, 1994Date of Patent: August 20, 1996Assignee: Ahlstrom Machinery Inc.Inventors: Tuomo S. Nykanen, Brian F. Greenwood, Johan Gullichsen, Erkki Kiiskila, Esko Mattelmaki, Joseph R. Phillips, Jan Richardsen, Rolf Ryham, Jarmo Soderman, Karl Wiklund
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Patent number: 5509997Abstract: Method of recovering energy from waste liquors from pulp processes, wherein the waste liquor is burned in a waste liquor recovery boiler and energy is recovered from the flue gases by producing saturated or partially superheated steam in the recovery boiler. According to the invention, a portion of the waste liquor is gasified in a gasifying reactor in order to produce combustion gas. The combustion gas is burned in a separate superheating boiler, in which the steam produced in the recovery boiler is superheated.Type: GrantFiled: May 12, 1994Date of Patent: April 23, 1996Assignee: A. Ahlstrom CorporationInventors: Marjo Kuusio, Samuli Nikkanen
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Patent number: 5507912Abstract: There is disclosed a process of increasing efficiency in a kraft pulping process that utilizes initial, bulk, and final delignification steps, a recovery boiler, and a caustic treatment step, which allows production of a white liquor stream that is separated into a sulphide-lean and sulphide-rich streams.Type: GrantFiled: December 15, 1993Date of Patent: April 16, 1996Assignee: H. A. Simons Ltd.Inventor: Patrik P. H. Lownertz
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Patent number: 5486269Abstract: A method and reactor for thermally decomposing a carbonaceous raw material (6) to recover gas and, if applicable, solid or liquid chemicals, the raw material being fed into a chamber (2) for gasification under under-stoichiometric conditions, the gasification is carried out in a gasification zone (15) at a pressure from atmospheric pressure up to about 150 bar and at a temperature within the range 500.degree.-1600.degree. C. According to the invention a part of the thermal energy required to maintain the endothermic reactions in the gasification zone (15) is produced by combustion of a fuel (8) in a combustion zone (16) located close to and in gaseous contact with the gasification zone, the raw material and fuel being supplied through different nozzle channels (12 and 13, respectively). An oxygen-containing gas (17) is supplied in an amount sufficient to oxidize substantially all the fuel.Type: GrantFiled: April 28, 1994Date of Patent: January 23, 1996Assignee: Chemrec AktiebolagInventor: Bengt Nilsson
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Patent number: 5454908Abstract: The invention relates to a method of firing black liquor in recovery boilers where the intention is to obtain fumes having a low content of nitrogen oxides (NO.sub.x). A part of the combustion air is added as a last portion at a very high level so that a reducing atmosphere will exist in a very great part of the boiler for a long time period, e.g. at least 3-5 seconds.Type: GrantFiled: August 27, 1993Date of Patent: October 3, 1995Assignee: Gotaverken Energy ABInventor: Lars Olausson
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Patent number: 5439557Abstract: A method of recovering energy and chemicals from a spent liquor which, after thickening to a dry content of 50-90%, is fed into a reaction chamber (1) in which a plurality of temperature zones are maintained, said method comprising the steps of (a) converting the liquid phase in the spent liquor to a steam phase, (b) thermally decomposing the spent liquor to form gaseous organic substances and solid and/or molten organic and inorganic substances, (c) reducing and (d) oxidizing said substances produced during the thermal decomposition, oxygen or oxygen-containing gas being supplied to the reaction chamber (1) in a controlled amount in order to maintain the reactions, which comprise combustion of organic substances, and a bed of said solid and/or molten substances being formed in a lower temperature zone in the reaction chamber (1). According to the invention said steps are carried out during exposure to low frequency sound.Type: GrantFiled: November 30, 1993Date of Patent: August 8, 1995Assignee: Gotaverken Energy AktiebolagInventor: Bengt Nilsson
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Patent number: 5425850Abstract: A black liquor gasification system intended for use as a replacement for a Tomlinson cycle, Chemical Recovery Unit, and which operates at a temperature below the ash melting temperature thereby removing the potential for smelt-water reactions and explosions. The subject black liquor gasification system is based on the use of a circulating fluidized bed operating at atmospheric pressure that produces dry, recoverable salts as well as low calorific gases to be used within the paper-making process.Type: GrantFiled: November 8, 1993Date of Patent: June 20, 1995Assignee: Combustion Engineering, Inc.Inventors: Michael C. Tanca, Erik G. A. Dahlquist, Sune Flink
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Patent number: 5405496Abstract: The invention relates to a process for preparation, under reducing conditions, of cooking liquors having high sulphidity for sulphate pulp cooking, wherein the black liquor obtained in the cooking process is fed, after evaporation, completely or partly to a reactor operating at increased temperature which is obtained by energy supply from an external heat source and/or release of energy from the black liquor, a melt essentially consisting of sodium sulphide being formed and withdrawn to be further processed to cooking liquor. The process of the invention is characterized in that in addition there are fed to the reactor the whole or part of sulphur-containing and/or sulphur- and sodium-containing materials present in the pulp mill, including sulphur-containing and/or sodium- and sulphur-containing make-up chemicals used for the total chemicals balance of the pulp mill, in such a way that the mole ratio of sodium to sulphur in the total mixture fed to the reactor is within the range of 1.5 to 4.Type: GrantFiled: January 3, 1994Date of Patent: April 11, 1995Assignee: Chemrec ABInventors: Mats-Olov Hedblom, Hans Lindberg
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Patent number: 5380402Abstract: A pulp mill has zero or minimum liquid discharges. The large amounts of liquid that must be processed to achieve this result are handled utilizing a multiple effect evaporator provided with heat from a steam exhaust of a condensing type steam turbine. Super heated steam from the recovery and bark boilers is fed to the turbine to generate electricity for the production of bleaching chemical and other uses in the mill. Three or four steam exhausts having different composite temperature and pressure values are taken from the turbine and used where most suitable in the pulp mill. For evaporation of bleach plant effluent the steam taken from the turbine preferably has a pressure of about 1-3 psia and a temperature of about 120.degree.-140 .degree. F, and has no significant adverse affect on power generation.Type: GrantFiled: October 13, 1992Date of Patent: January 10, 1995Assignee: Kamyr, Inc.Inventors: Rolf Ryham, Tuomo S. Nykanen, Brian F. Greenwood, Johan Gullichsen, Erkki Kiiskila, Esko Mattelmaki, Joseph R. Phillips, Jan Richardsen, Jarmo Soderman, Karl G. Wiklund
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Patent number: 5374333Abstract: Apparatus for a pulp and paper mill, and methods of acting on liquid effluents produced in the mill, which minimizes the discharge of polluting gaseous and liquid effluents to the environment. Liquid effluents from the bleach plant are concentrated (e.g. evaporated), incinerated (e.g. gasified), leached, crystallized (e.g. freeze crystallized) then washed, and then fed to the plant chemical recovery loop. White liquor produced from the recovery boiler melt is fully oxidized and used in place of caustic in the bleach plant. Essentially all sulfuric acid, sulfur dioxide, caustic, and chlorine dioxide necessary for the pulp mill is produced from mill liquid effluents and gas waste streams, on site at the pulp mill. Typical bleaching sequences that can be used are DE.sub.op D.sub.n D, or AZE.sub.o PZP.Type: GrantFiled: July 30, 1992Date of Patent: December 20, 1994Assignee: Kamyr, Inc.Inventors: Tuomo S. Nykanen, Brian F. Greenwood, Johan Gullichsen, Erkki Kiiskila, Esko Mattelmaki, Joseph R. Phillips, Jan Richardsen, Rolf Ryham, Jarmo Soderman, Karl G. Wiklund