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US20040050301A1 - Method and device for the production of concrete - Google Patents

Method and device for the production of concrete Download PDF

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Publication number
US20040050301A1
US20040050301A1 US10/416,051 US41605103A US2004050301A1 US 20040050301 A1 US20040050301 A1 US 20040050301A1 US 41605103 A US41605103 A US 41605103A US 2004050301 A1 US2004050301 A1 US 2004050301A1
Authority
US
United States
Prior art keywords
cold
transfer agent
cold gas
water
cooling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/416,051
Other languages
English (en)
Inventor
Erich Lindner
Dieter Reichel
Jens Tauchmann
Thomas Weichmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of US20040050301A1 publication Critical patent/US20040050301A1/en
Abandoned legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/06—Inhibiting the setting, e.g. mortars of the deferred action type containing water in breakable containers ; Inhibiting the action of active ingredients
    • C04B40/0683—Inhibiting the setting, e.g. mortars of the deferred action type containing water in breakable containers ; Inhibiting the action of active ingredients inhibiting by freezing or cooling
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P25/00—Drugs for disorders of the nervous system
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B22/00—Use of inorganic materials as active ingredients for mortars, concrete or artificial stone, e.g. accelerators or shrinkage compensating agents
    • C04B22/002—Water
    • C04B22/0053—Water added in a particular physical form, e.g. atomised or in the gas phase
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028—Aspects relating to the mixing step of the mortar preparation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25C—PRODUCING, WORKING OR HANDLING ICE
    • F25C2303/00—Special arrangements or features for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Special arrangements or features for producing artificial snow
    • F25C2303/044—Snow making using additional features, e.g. additives, liquid gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25C—PRODUCING, WORKING OR HANDLING ICE
    • F25C3/00—Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow
    • F25C3/04—Processes or apparatus specially adapted for producing ice or snow for winter sports or similar recreational purposes, e.g. for sporting installations; Producing artificial snow for sledging or ski trails; Producing artificial snow

Definitions

  • the invention relates to a method and to a device for the production of concrete.
  • a drawback of cooling by means of cryogenic nitrogen (LN 2 ) is the fact that this method is not very efficient since relatively large amounts of LN 2 have to be fed into the batch in question within a short period of time in order to achieve the desired cooling effect.
  • the poor efficiency of this cooling method lies in the fact that primarily only the evaporation heat of the liquid nitrogen can be utilized and that the surface area available for the heat exchange is limited.
  • the fast evaporation of the nitrogen causes large volumes of gas to be released within the shortest of times, and this can lead to local explosions and ejections from the mixer.
  • the fresh concrete can suffer frost damage.
  • JP 61201681 A1 suggests adding a liquefied gas, such as nitrogen or carbon dioxide, in order to cool down the starting materials prior to adding cement and water.
  • a liquefied gas such as nitrogen or carbon dioxide
  • This method can only be employed with certain restrictions since the cooled medium has to be kept insulated against heat and moisture.
  • substances with a high moisture content cannot be cooled to temperatures below 0° C. [32° F.].
  • the objective of the present invention is to put forward a method as well as a device for the production of concrete which avoid the disadvantages of the prior-art cooling methods and which particularly allow a cost-effective use of the coolant while concurrently providing a high cooling output.
  • either some or all of the water added to the binder mixture consisting of a binder, such as cement, and of aggregates, such as gravel, sand, fly ash and the like, is in the form of a previously prepared cold transfer agent made up of snow crystals.
  • now crystals as employed throughout the text is to be understood as particles of frozen water that are generated in a cold atmosphere.
  • a cold gas is made from water, a propellant as well as a coolant and this gas is then sprayed in the form of a cold gas stream into a spraying chamber.
  • This cold gas stream is at a temperature that is clearly below the freezing temperature of water.
  • the water present in the cold gas stream freezes to form crystals that are subsequently admixed with a binder mixture in order to produce fresh concrete.
  • the size, temperature and surface characteristics of the crystals are decisively determined by the composition of the cold gas and by the temperature of the cold gas stream.
  • the production of crystals at temperatures well below 0° C. [32° F.] is likewise possible without any problems. In particular, at temperatures below ⁇ 30° C.
  • the crystals formed exhibit especially good transport properties since, at these temperatures, microscopic domains of liquid water that could cause the snow crystals to adhere to each other are no longer present on the surface of the snow crystals. Therefore, the cooling action of the coolant is utilized to a far greater extent than in conventional cooling methods.
  • the cold gas stream is made to rotate. This lengthens the stream path in the stream chamber, thus achieving greater homogeneity of the crystals formed.
  • the cold transfer agent generated in the spraying chamber is subjected to an after-cooling procedure.
  • a suitable coolant for instance, liquid nitrogen, snow crystal temperatures as low as ⁇ 190° C. [ ⁇ 310° F.] can be generated.
  • a cryogenic gas is the preferred coolant for the production of the cold gas as well as for the after-cooling procedure.
  • the use of liquid nitrogen or liquid carbon dioxide is particularly recommended from an environmental and cost standpoint.
  • Gaseous nitrogen is advantageously employed as the propellant for the production of the cold gas or of the cold gas stream.
  • the liquid coolant used preferably also serves to transport the cold transfer agent from the spraying chamber to the binder mixture.
  • the cold transfer agent can be discharged virtually without compressing, clumping or altering the crystal structure of the snow or ice crystals.
  • the device according to the invention as cited in claim 8 comprises a mixing device in which water, a propellant, for instance, nitrogen, and a coolant, for example, liquid nitrogen, are mixed together to form a cold gas, said mixing device being flow-connected to a spraying device housed in the spraying chamber.
  • a spraying device housed in the spraying chamber.
  • the spraying of the cold gas into the spraying chamber gives rise to an inert and sub-cooled atmosphere therein and this promotes the formation of snow crystals having a large surface area and low specific weight.
  • the cold transfer agent generated in the spraying chamber is fed to a mixing chamber, where it can be mixed together with a binder mixture to form fresh concrete.
  • the spraying chamber is associated with a cooling unit with which the snow created in the spraying chamber can be further cooled to a specified temperature.
  • a suitable coolant in the cooling unit temperatures of ⁇ 30° C. to ⁇ 190° C. [ ⁇ 22° F. to ⁇ 310° F.] can be attained.
  • the mixing device for generating the cold gas and/or the mixing chamber for making the fresh concrete are connected to a control unit by means of which the composition of the cold gas and/or of the fresh concrete can be set in accordance with a specified program. Aside from the geometry of the spraying nozzle, it is the composition of the cold gas that decisively determines the consistency and temperature of the generated cold transfer agent.
  • the feed is regulated by suitable valves on the mixing device or mixing chamber that are operated by the control unit.
  • FIG. 1 schematically shows the mode of operation of a device according to the invention for the production of fresh concrete.
  • the device 1 has a conventional mixing chamber 2 which receives the aggregates needed for the production of fresh concrete such as sand, gravel, fly ash as well as cement, and these are mixed to form a binder mixture Z.
  • the mixing chamber can be, for instance, a mobile or stationary mixing installation. Instead of the water in liquid form employed in common production methods, a sub-cooled cold transfer agent S is added to the binder mixture in the mixing chamber 2 ; the preparation of said cold transfer agent will be described below.
  • the lines 4 , 5 , 6 can also open up directly into the spraying nozzle 8 , which is then configured as a three-component nozzle for this purpose.
  • the invention is not limited to liquid nitrogen as the coolant for the production of the cold gas mixture, but rather, other known coolants, especially other liquefied gases, can also be employed for this purpose.
  • a different multi-nozzle system can also be used instead of a three-component nozzle.
  • the cold gas mixture is emitted in the form of a cold gas stream aimed at the interior of the spraying chamber 9 , whereby the cold gas stream is made to rotate around its own axis in order to lengthen the stream path.
  • the feeding of the cold gas stream causes a sub-cooled atmosphere to form inside the spraying chamber 9 already after a short time.
  • the water contained in the cold gas stream freezes and precipitates inside the spraying chamber 9 in the form of snow crystals, i.e. the cold transfer agent S.
  • the cold, inert atmosphere inside the spraying chamber 9 promotes the formation of crystals having a large surface area and a low specific weight.
  • the size, consistency and temperature of the crystals are especially determined by the mixing ratio of gaseous and liquid nitrogen as well as water in the cold gas mixture.
  • the snow crystals formed in the spraying chamber 9 are fed into an after-cooling unit 10 , where the cold transfer agent S is cooled down further.
  • the after-cooling unit 10 consists of a cooling chamber 11 for the material to be cooled, which is in thermal contact with a cold transfer agent 12 .
  • the snow crystals can be transported very well at temperatures below ⁇ 30° C. [ ⁇ 22° F.], for instance, ⁇ 40° C. [ ⁇ 40° F.].
  • the cold transfer agent S thus cooled is conveyed to the mixing chamber 2 , where it is admixed with aggregates and with cement in a known manner to form fresh concrete.
  • the large surface area of the snow crystals of the cold transfer agent S allows an effective and fast absorption of the process heat generated during the setting process of the cement.
  • fresh concrete temperatures as low as 0° C. [32° F.] can be reached.
  • An electronic control unit 13 allows the production of the cold transfer agent S or of the fresh concrete according to a specified program.
  • the electronic control unit 13 is connected to actuatable valves 14 , 15 , 16 , for instance, solenoid valves, in the lines 4 , 5 , 6 , by means of which the mixing ratio and/or the appertaining pressure in lines 4 , 5 , 6 can be set.
  • a control line 17 serves to regulate the temperature in the after-cooling unit 10 .
  • the feed line 18 for the cold transfer agent S to the mixing chamber 2 is likewise fitted with a solenoid valve 19 that can be actuated by the control unit 13 .
  • the temperature, consistency and amount of the cold transfer agent S fed to the binder mixture Z can all be precisely and reliably set and, for example, selected in such a way that the fresh concrete made has a certain temperature, for instance, 0° C. [32° F.].
  • the temperature of the fresh concrete which is continuously or regularly measured with an appropriate measuring device, is utilized as the manipulated variable to which the value is constantly regulated by setting the temperature of the added cold transfer agent S.
  • the method according to the invention makes it possible to convert the feed water into cold transfer agent S within a few minutes. Due to the large surface area of the snow crystals, the transfer of cold during the after-cooling procedure is very effective, so that this procedure, too, only takes a few minutes.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • Neurosurgery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Biomedical Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Neurology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Preparation Of Clay, And Manufacture Of Mixtures Containing Clay Or Cement (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Medicinal Preparation (AREA)
  • Devices For Post-Treatments, Processing, Supply, Discharge, And Other Processes (AREA)
  • On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
US10/416,051 2000-11-03 2001-10-19 Method and device for the production of concrete Abandoned US20040050301A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10054563.7 2000-11-03
DE10054563A DE10054563A1 (de) 2000-11-03 2000-11-03 Verfahren und Vorrichtung zur Betonherstellung
PCT/EP2001/012100 WO2002036523A1 (fr) 2000-11-03 2001-10-19 Procede et dispositif de preparation du beton

Publications (1)

Publication Number Publication Date
US20040050301A1 true US20040050301A1 (en) 2004-03-18

Family

ID=7662062

Family Applications (2)

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US10/416,051 Abandoned US20040050301A1 (en) 2000-11-03 2001-10-19 Method and device for the production of concrete
US11/767,604 Expired - Fee Related US7700135B2 (en) 2000-11-03 2007-06-25 Cerebral protection with a xenon-containing gas

Family Applications After (1)

Application Number Title Priority Date Filing Date
US11/767,604 Expired - Fee Related US7700135B2 (en) 2000-11-03 2007-06-25 Cerebral protection with a xenon-containing gas

Country Status (7)

Country Link
US (2) US20040050301A1 (fr)
EP (1) EP1337498B1 (fr)
AT (1) ATE378304T1 (fr)
AU (1) AU2002215031A1 (fr)
DE (2) DE10054563A1 (fr)
WO (1) WO2002036523A1 (fr)
ZA (1) ZA200304310B (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220194866A1 (en) * 2019-04-25 2022-06-23 L'Air Liquide, Société Anonyme pour I'Etude et I'Exploitation des Procédés Georges Claude Method for adhering to fresh concrete temperatures
US12044447B2 (en) 2017-03-06 2024-07-23 Nitrocrete Ip, Llc Cooling system and method
SE2450470A1 (en) * 2024-04-30 2025-10-31 Svante Syk Method and device for producing snow from water, liquid nitrogen and air

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004010129B3 (de) * 2004-03-02 2005-09-01 GÖTZ, Werner Vorrichtung und Verfahren zur Herstellung von vorgekühltem Beton
DE102004021061B4 (de) * 2004-04-29 2006-04-20 GÖTZ, Werner Vorrichtung und Verfahren zur Erzeugung von Kunstschnee für die Herstellung von vorgekühltem Beton
DE102004043498A1 (de) * 2004-09-06 2006-03-09 KTI-Plersch Kältetechnik GmbH Eislager
DE102006047261B4 (de) 2006-10-04 2019-06-06 Messer Group Gmbh Verfahren und Vorrichtung zur Herstellung von gekühltem Frischbeton
DE102007008811B3 (de) * 2007-02-22 2008-07-10 Messer Group Gmbh Verfahren und Vorrichtung zur Herstellung von gekühltem Frischbeton
ATE543621T1 (de) 2006-10-04 2012-02-15 Messer Group Gmbh Verfahren und vorrichtung zur herstellung von gekühltem frischbeton
US9526863B2 (en) * 2009-02-08 2016-12-27 Neuronal Protection System, Llc Devices and methods for perfusion therapy
WO2010091376A2 (fr) * 2009-02-08 2010-08-12 Blaise Baxter Dispositifs et procédé de traitement par perfusion
CN110464709A (zh) 2012-08-10 2019-11-19 德克萨斯州大学系统董事会 用于治疗中风的神经保护性脂质体组合物和方法
CN103970076A (zh) * 2013-01-30 2014-08-06 张永生 一种大体积浇注混凝土冷却通水智能控制系统
WO2014145443A2 (fr) 2013-03-15 2014-09-18 The Board Of Regents Of The University Of Texas System Liquides riches en gaz noble et leurs procédés de préparation et d'utilisation
US20210322463A1 (en) * 2018-07-18 2021-10-21 Likeminds, Inc. Method for accelerated tissue penetration of compounds into brain

Citations (1)

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US3762176A (en) * 1969-09-18 1973-10-02 B Coggins Method and apparatus for making snow

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FR2195184A5 (en) * 1972-08-04 1974-03-01 Girod Edgar Storing and transporting mixed concrete - by separately cooling all solids and freezing necessary water to broken-up ice, and mixing and storing cold
SE368948B (fr) * 1972-11-07 1974-07-29 Innovationsteknik Inst Ab
US4344290A (en) * 1981-08-24 1982-08-17 Air Products And Chemicals, Inc. Process and apparatus for in-line slush making for concrete cooling
JPS61201681A (ja) 1985-03-04 1986-09-06 株式会社大林組 骨材の冷却方法およびその装置
AU590743B2 (en) * 1985-07-03 1989-11-16 Toshiro Suzuki Process for producing mortar and method for applying the same
JPH01123705A (ja) * 1987-11-10 1989-05-16 Hazama Gumi Ltd コンクリートの製造方法とその装置
JP2617115B2 (ja) * 1988-06-14 1997-06-04 清水建設株式会社 コンクリート製造方法及びコンクリート成型品製造方法
JPH03110364A (ja) * 1989-06-07 1991-05-10 Mitsubishi Electric Corp 製氷器およびコンクリート製造装置
CZ291660B6 (cs) * 1996-07-20 2003-04-16 Max Bögl Bauunternehmung GmbH & Co. KG Způsob výroby čerstvého betonu s betonovou směsí a s částicemi ledu z vody a zařízení k provádění tohoto způsobu
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12044447B2 (en) 2017-03-06 2024-07-23 Nitrocrete Ip, Llc Cooling system and method
US20220194866A1 (en) * 2019-04-25 2022-06-23 L'Air Liquide, Société Anonyme pour I'Etude et I'Exploitation des Procédés Georges Claude Method for adhering to fresh concrete temperatures
US12344562B2 (en) * 2019-04-25 2025-07-01 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method for adhering to fresh concrete temperatures
SE2450470A1 (en) * 2024-04-30 2025-10-31 Svante Syk Method and device for producing snow from water, liquid nitrogen and air
SE547864C2 (en) * 2024-04-30 2025-12-09 Svante Syk Method and device for producing snow from water, liquid nitrogen and air

Also Published As

Publication number Publication date
DE10054563A1 (de) 2002-05-16
ZA200304310B (en) 2004-09-02
DE50113275D1 (de) 2007-12-27
EP1337498B1 (fr) 2007-11-14
AU2002215031A1 (en) 2002-05-15
WO2002036523A1 (fr) 2002-05-10
US7700135B2 (en) 2010-04-20
ATE378304T1 (de) 2007-11-15
EP1337498A1 (fr) 2003-08-27
US20080206157A1 (en) 2008-08-28

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