NO156207B - PROTECTIVE COATING LAYER. - Google Patents

PROTECTIVE COATING LAYER. Download PDF

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Publication number
NO156207B
NO156207B NO832259A NO832259A NO156207B NO 156207 B NO156207 B NO 156207B NO 832259 A NO832259 A NO 832259A NO 832259 A NO832259 A NO 832259A NO 156207 B NO156207 B NO 156207B
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NO
Norway
Prior art keywords
water
cement
gypsum
amount
coating layer
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NO832259A
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Norwegian (no)
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NO156207C (en
NO832259L (en
Inventor
Bengt Louis Christi Hellstroem
Nils Gottfrid Johansson
Original Assignee
Boliden Ab
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Publication date
Application filed by Boliden Ab filed Critical Boliden Ab
Publication of NO832259L publication Critical patent/NO832259L/en
Publication of NO156207B publication Critical patent/NO156207B/en
Publication of NO156207C publication Critical patent/NO156207C/en

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Classifications

    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/14Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing calcium sulfate cements
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B26/00Compositions of mortars, concrete or artificial stone, containing only organic binders, e.g. polymer or resin concrete
    • C04B26/02Macromolecular compounds
    • C04B26/28Polysaccharides or derivatives thereof
    • C04B26/285Cellulose or derivatives thereof
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K21/00Fireproofing materials
    • C09K21/02Inorganic materials
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K21/00Fireproofing materials
    • C09K21/14Macromolecular materials
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00Materials not provided for elsewhere
    • C09K3/22Materials not provided for elsewhere for dust-laying or dust-absorbing

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Structural Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paints Or Removers (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Materials For Medical Uses (AREA)

Description

Foreliggende oppfinnelse..anqår et beskvttende belegninassjikt for å hindre støving og/eller vannutvasking og/eller brannspredning. The present invention..regards a polluting coating layer to prevent dusting and/or water leaching and/or the spread of fire.

Formålet med foreliggende oppfinnelse er å tilveiebringe The purpose of the present invention is to provide

en mulighet for å hindre støving, vannutvasking eller brannspredning ved å belegge produkter og gjenstander med et i og for seg mekanisk lett gjennomtrengelig beskyttelsessjikt. an opportunity to prevent dusting, water washout or the spread of fire by coating products and objects with an inherently mechanically easily permeable protective layer.

I industrien tvinges man ofte til å lagre støvende produkter utendørs, hvorved omgivelsen lett forurenses når det blåser. Videre forekommer utendørs lagring av såvel støvende produkter som ikke-støvende produkter hvor regn og - sne kan medføre skader på produktene eller utvasking av giftige materialer eller materialer som har til hensikt å gi produktene visse egenskaper. Eksempelvis lagres store mengder grus og sand utendørs, som er beregnet for isstrøing vinters-tid. Denne grus er oppblandet med salt for å hindre en sammenfrysihg av haugene som ville gjøre grusen/sanden util-gjengelig. Imidlertid medfører varierende perioder av ned-bør og mildvær at vann passerer gjennom haugene og dermed vasker saltet ut, hvorved frostbeskyttelsen elimineres og haugene fryser sammen. In industry, you are often forced to store dusty products outdoors, whereby the environment is easily polluted when it is windy. Furthermore, outdoor storage of dusty products as well as non-dusty products occurs where rain and snow can cause damage to the products or leaching of toxic materials or materials intended to give the products certain properties. For example, large quantities of gravel and sand are stored outdoors, which are intended for ice spreading in winter. This gravel is mixed with salt to prevent freezing of the piles which would make the gravel/sand unavailable. However, varying periods of downpours and mild weather cause water to pass through the piles and thus wash the salt out, whereby the frost protection is eliminated and the piles freeze together.

Et annet eksempel er kulldepoter som ofte støver og foru-renser omgivelsene, spesielt i depoter i kullgruvene. Another example is coal depots which often dust and pollute the surroundings, especially in depots in coal mines.

I visse tilfeller kan det være ønskelig å utruste gjenstander med et ikke permanent brannbeskyttende sjixt, eksempelvis i forbindelse med sveisearbeider inntil brennbart materi-ale . In certain cases, it may be desirable to equip objects with a non-permanent fire protection coating, for example in connection with welding work up to combustible material.

Det er tidligere foreslått beskyttelsessjikt for kulldepoter (US patentskrift nr. 4 269 721) hvor man fremstiller et gipssjikt på depotet. Imidlertid har gips den ulempe at den er vannløselig, og beskyttelsessjiktet kommer derfor til å oppløses etterhvert som det utsettes for vannoversprøyting, eksempelvis i form av nedbør. A protective layer for coal depots has previously been proposed (US patent no. 4 269 721) where a plaster layer is produced on the depot. However, gypsum has the disadvantage that it is water-soluble, and the protective layer will therefore dissolve as it is exposed to water overspray, for example in the form of precipitation.

Andre beskyttelsessjikt bestående av natriumklorid, leire og vann er kjente TUS patentskrift nr. 3 896 039) , men de fremviser samme ulemper som gips ved at de er vannløselige og altså ikke gir beskyttelse ved utendørs lagring. Videre størkner ikke produktene tilstrekkelig hurtig, hvilket er et annet krav man stiller ved utendørs lagring. Other protective layers consisting of sodium chloride, clay and water are known from TUS patent document no. 3 896 039), but they exhibit the same disadvantages as gypsum in that they are water-soluble and therefore do not provide protection during outdoor storage. Furthermore, the products do not solidify quickly enough, which is another requirement for outdoor storage.

Også andre støvhindrende sjikt er kjente (GB patentskrift nr. 1 245 156, GB patentskrift nr. 1 267 621 og GB patentskrift nr. 1 267 617), hvorved et hygroskopisk salt og eksempelvis gips blandes med vann og påføres de produkter man vil hindre støving ifra. Disse sjikt er også vannløselige. Other dust-preventing layers are also known (GB patent document no. 1 245 156, GB patent document no. 1 267 621 and GB patent document no. 1 267 617), whereby a hygroscopic salt and, for example, gypsum is mixed with water and applied to the products you want to prevent dusting from. These layers are also water soluble.

Det er kjent en metode for å undertrykke støving ved fjellsprengning fra GB patentskrift nr. 1 391 115, hvorved fjellet påsprøytes en vannløsning av et polysaccharid som guargummi og natriumcarboxylmethylcellulose. Denne løsning kan gi en kortvarig beskyttelse mot støving, men den gir ingen varig beskyttelse. A method for suppressing dusting during rock blasting is known from GB Patent No. 1 391 115, whereby the rock is sprayed with a water solution of a polysaccharide such as guar gum and sodium carboxyl methyl cellulose. This solution may provide short-term protection against dusting, but it does not provide permanent protection.

Et flammebestandig beskyttelsessjikt er kjent fra SE patentsøknad nr. 7 603 820-7 bestående av en uorgan- A flame-resistant protective layer is known from SE patent application no. 7 603 820-7 consisting of an inorganic

isk komponent som omfatter en vannløsning av et alkalimetall-silikat, leire og asbestfibre samt en organisk komponent som omfatter en vannløsning av carboxymethylcellulose, en stivelseester og/eller et dextri^hvori den organiske kompo- ical component comprising an aqueous solution of an alkali metal silicate, clay and asbestos fibers as well as an organic component comprising an aqueous solution of carboxymethylcellulose, a starch ester and/or a dextri^in which the organic component

nent utgjør opptil noen prosent av den totale blanding. En slik blanding har imidlertid altfor lang herdetid, > 48 timer. nent constitutes up to a few percent of the total mixture. However, such a mixture has a far too long curing time, > 48 hours.

For et beskyttelsessjikt beregnet til utendørs beskyttelse kreves det blant annet at det skal beskytte effektivt mot fuktighet helst innen noen timer og senest innen 2 4 timer, at det ikke skal være oppløselig innen rimelig tid hvilket betyr fra 6 til 8 måneder, at det skal være miljøvennlig og ikke skade belagte produkter samt at det skal være lett mekanisk gjennomtrengelig slik at lagrede produkter er lett tilgjengelige. Ved lagring av produkter med lav verdi må dessuten beskyttelsen ikke koste alt for mye. For a protective layer intended for outdoor protection, it is required, among other things, that it must protect effectively against moisture preferably within a few hours and within 2 4 hours at the latest, that it must not be soluble within a reasonable time, which means from 6 to 8 months, that it must be environmentally friendly and not damage coated products and that it must be easily mechanically permeable so that stored products are easily accessible. Furthermore, when storing low-value products, the protection must not cost too much.

Det har overraskende vist seg mulig å innfri de ovenfor nevnte krav ved hjelp av foreliggende oppfinnelse som karakteriseres ved at beskyttelsesjiktet foruten av gips består av sement og ethylhydroxyethylcellulose, idet vektforholdet gips .-sement ikke overstiger 6:1, og av den nødvendige mengde vann for størkning av gips og sement, idet mengden av ethylhydroxyethylcellulose utgjør 0,2-3 vekt% av inngående vann, og at sjiktet dessuten kan inneholde kalsiumklorid i en mengde av 0-2 vekt%. It has surprisingly proved possible to fulfill the above-mentioned requirements with the help of the present invention, which is characterized by the fact that the protective layer, in addition to gypsum, consists of cement and ethylhydroxyethylcellulose, the weight ratio of gypsum to cement not exceeding 6:1, and of the necessary amount of water for solidification of plaster and cement, with the amount of ethylhydroxyethylcellulose constituting 0.2-3% by weight of the water included, and that the layer may also contain calcium chloride in an amount of 0-2% by weight.

Ekse mpel 1 Example 1

En 1% vannoppløsning av ethylhydroxyethylcellulose (Bermocoll E 481, Berol Kemi, Stenungsund, Sverige) ble fremstilt. I et blandingskar som rommet 7 m 3 ble det blandet totalt 5 m<3> bestående av 44 deler CaS04 . 2 H20, 22 deler sement samt 34 deler av nevnte 1% ethylhydroxyethylcellulose-vannløsning. Den totale vekt av blandingen var 6,7 tonn. Blandingen ble homogenisert ved omrøring med padlerørere i A 1% aqueous solution of ethylhydroxyethylcellulose (Bermocoll E 481, Berol Kemi, Stenungsund, Sweden) was prepared. In a mixing vessel with a volume of 7 m 3 , a total of 5 m<3> consisting of 44 parts CaS04 was mixed. 2 H2O, 22 parts cement and 34 parts of the aforementioned 1% ethylhydroxyethylcellulose water solution. The total weight of the mixture was 6.7 tonnes. The mixture was homogenized by stirring with paddle stirrers i

1 time. 1 hour.

Denne oppslemming med en viskositet på ca. 1000 cP ble sprøytet over et sanddepot som inneholdt ca. 1200 m sand, hvorved først toppen og deretter sidene ble oversprøytet. Det pålagte sjikt størknet hurtig og var hardt etter ca. 11 timer. Beskyttelsessjiktet hadde middels tykkelse på ca. 5 mm. Beskyttelsessjiktet ble hélt stabilt innen 20 timer, det var praktisk talt uløselig i vann og viste etter størkning en vann-permeabilitet på lxlO- meter/sekund. This slurry with a viscosity of approx. 1000 cP was sprayed over a sand depot containing approx. 1200 m of sand, whereby first the top and then the sides were sprayed over. The applied layer solidified quickly and was hard after approx. 11 hours. The protective layer had a medium thickness of approx. 5 mm. The protective layer was held stable within 20 hours, it was practically insoluble in water and after solidification showed a water permeability of 1x10 meters/second.

Eksempel A- D Example A-D

Ulike belegningssjikt med andre bestanddeler ble fremstilt for å sammenlignes med det ovenfor fremstilte, etter følgende oppskrifter. Different coating layers with other components were prepared to be compared with the above prepared, according to the following recipes.

A. A.

B. i C. D. B. in C. D.

Blandingene ifølge A og D ga stabile beskyttelsessjikt først etter mer enn 2 døgn. Blandingene ifølge B og C størknet innen rimelig tid,10 til 24 timer, men begge var vannløselige. The mixtures according to A and D gave stable protective layers only after more than 2 days. The mixtures according to B and C solidified within a reasonable time, 10 to 24 hours, but both were water soluble.

Ved fremstilling av blandingene ifølge oppfinnelsen til-føres fortrinnsvis bare så meget vann som bindes av sjiktet under størkning, dvs. det vann som hovedsakelig opptaes av sementen. Fordelaktig viskositet ved fremstilling, transport og påføring er fra 500 til 1500 cPs. When preparing the mixtures according to the invention, preferably only as much water is added as is bound by the layer during solidification, i.e. the water that is mainly taken up by the cement. Advantageous viscosity during manufacture, transport and application is from 500 to 1500 cPs.

Ethylhydroxyethylcellulosen som anvendes som bindemiddel kan inngå i en mengde av fra 0,2 til 3% i vannløsningen. Ved større mengder kan ikke vannløsningen håndteres på grunn av cellulosederivatets svelning. The ethylhydroxyethylcellulose used as a binder can be included in an amount of from 0.2 to 3% in the water solution. In the case of larger amounts, the water solution cannot be handled due to the swelling of the cellulose derivative.

Sementmengden i produktet kan selvsagt være stor, men dette fordyrer produktet vesentlig. Vektforholdet mellom gips og sement bør være ca. 3:1, men det bør aldri overstige 6:1 ettersom løseligheten da blir altfor stor og den fysiske styrke reduseres. Gipsmengden bør fortrinnsvis ikke være mindre enn mengden av sement av prismessige hensyn. The amount of cement in the product can of course be large, but this makes the product significantly more expensive. The weight ratio between plaster and cement should be approx. 3:1, but it should never exceed 6:1 as the solubility then becomes far too great and the physical strength is reduced. The amount of plaster should preferably not be less than the amount of cement for price reasons.

Den anvendte gips bør ikke være altfor grovkornet, men The plaster used should not be excessively coarse-grained, however

ha en hovedsakelig partikkelstørrelse Då under 0,25 mm og med samtlige partikler mindre enn 1 mm. have a mainly particle size of less than 0.25 mm and with all particles smaller than 1 mm.

Gipsen som omtales i det foregående eksempel var(en di-hydratgips, CaSO^ ; 21^0, men også anhydridgips eller semihydratgips kan anvendes. Ved anvendelse av senere angitte kvaliteter skjer en sterkere størkning og sammenbinding ved at gipsen omleires til dihydratform. Ved anvendelse av anhydridgips og semihydratgips må vannmengden i blandingstrinnet økes noe. Den totale vannmengde i det ferdige sjikt er like-vel den damme. The gypsum referred to in the previous example was (a di-hydrate gypsum, CaSO^ ; 21^0, but also anhydride gypsum or semi-hydrate gypsum can be used. When using the qualities specified later, a stronger solidification and binding takes place by the gypsum being converted into dihydrate form. When using of anhydride gypsum and semi-hydrate gypsum, the amount of water in the mixing step must be increased somewhat.The total amount of water in the finished layer is still the same.

For å akselerere herdningen kan beskyttelsessjiktproduktet tilføres CaCl2 i en mengde på opptil 2 vekt%. To accelerate the curing, CaCl2 can be added to the protective layer product in an amount of up to 2% by weight.

Avhengig av typen av depot og produkt, lagringsplass, og en rekke andre omstendigheter kan beskyttelsessjiktets tykkelse variere fra 1 til lu mm, fortrinnsvis fra 2 til 5 mm. Depending on the type of depot and product, storage space, and a number of other circumstances, the thickness of the protective layer can vary from 1 to 1 mm, preferably from 2 to 5 mm.

Ved tilberedelse på plassen ved et decot kan det When preparing on the spot at a decot, it can

være vanskelig å bestemme produktets mest egnede viskositet. Det har vist seg formålstjenlig å utføre en trakttest, dvs. at man fyller en trakt med blandingen og tar tiden på hvor hurtig eller langsomt trakten tømmes. Viskositeten for et produkt med en sammensetning av 225 g CaS04* 2H2O, 75 g sement, 1,5 g ethylhydroxyethylcellulose og 180 g vann an-sees å være passende. Denne blanding renner på 5 0 sekunder gjennom en trakt med en høyde på 80 mm, en øvre diameter på 12 0 mm og en nedre diameter på 14 mm. Dersom vannmengden er 170 g>er tiden 90 sekunder, og dersom vannmengden er 190 g,er tiden 35 sekunder. be difficult to determine the product's most suitable viscosity. It has proven useful to carry out a funnel test, i.e. filling a funnel with the mixture and timing how quickly or slowly the funnel empties. The viscosity of a product with a composition of 225 g of CaSO 4 * 2 H 2 O, 75 g of cement, 1.5 g of ethylhydroxyethyl cellulose and 180 g of water is considered to be suitable. This mixture flows in 50 seconds through a funnel with a height of 80 mm, an upper diameter of 120 mm and a lower diameter of 14 mm. If the amount of water is 170 g, the time is 90 seconds, and if the amount of water is 190 g, the time is 35 seconds.

Claims (3)

1. Beskyttende belegningssjikt som hindrer støving, vannutvasking eller brannspredning og som inneholder gips, karakterisert ved at det foruten av gips består av sement og ethylhydroxyethylcellulos<=, idet vektforholdet gips:sement ikke overstiger 6:1, og av den nødvendige mengde vann for størkning av gips og sement, idet mengden av ethylhydroxyethylcellulose utgjør 0,2-3 vekt% av inngående vann, og at sjiktet dessuten kan inneholde kalsiumklorid i en mengde av 0-2 vekt%.1. Protective coating layer that prevents dusting, water washout or the spread of fire and that contains gypsum, characterized in that, in addition to gypsum, it consists of cement and ethylhydroxyethylcellulose<=, the weight ratio of gypsum:cement does not exceed 6:1, and of the required amount of water for solidification of plaster and cement, the amount of ethylhydroxyethylcellulose being 0.2-3% by weight of the water included, and that the layer may also contain calcium chloride in an amount of 0-2% by weight. 2. Belegningssjikt ifølge krav 1, karakterisert ved at vektforholdet gips: sement er 3:1.2. Coating layer according to claim 1, characterized in that the weight ratio plaster: cement is 3:1. 3. Belegningssjikt ifølge krav 1 eller 2, karakterisert ved at det har en tykkelse av 1-10 mm, fortrinnsvis 2-5 mm.3. Coating layer according to claim 1 or 2, characterized in that it has a thickness of 1-10 mm, preferably 2-5 mm.
NO832259A 1982-06-23 1983-06-22 PROTECTIVE COATING LAYER. NO156207C (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE8203897A SE455308B (en) 1982-06-23 1982-06-23 PROTECTIVE LAYER INCLUDING GYPS, CEMENT AND ETHYL HYDROXICELLULOSA

Publications (3)

Publication Number Publication Date
NO832259L NO832259L (en) 1983-12-27
NO156207B true NO156207B (en) 1987-05-04
NO156207C NO156207C (en) 1987-08-12

Family

ID=20347162

Family Applications (1)

Application Number Title Priority Date Filing Date
NO832259A NO156207C (en) 1982-06-23 1983-06-22 PROTECTIVE COATING LAYER.

Country Status (4)

Country Link
DK (1) DK158742C (en)
FI (1) FI71334C (en)
NO (1) NO156207C (en)
SE (1) SE455308B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994015886A1 (en) * 1993-01-13 1994-07-21 Nachtman Thomas J Sprayable composition and method for forming a foamed outdoor protective cover layer

Also Published As

Publication number Publication date
SE455308B (en) 1988-07-04
DK267083A (en) 1983-12-24
FI71334B (en) 1986-09-09
FI71334C (en) 1986-12-19
DK158742C (en) 1990-12-03
FI832297L (en) 1983-12-24
NO156207C (en) 1987-08-12
NO832259L (en) 1983-12-27
DK158742B (en) 1990-07-09
SE8203897L (en) 1983-12-24
DK267083D0 (en) 1983-06-10
SE8203897D0 (en) 1982-06-23
FI832297A0 (en) 1983-06-22

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