NO151648B - PROCEDURE FOR THE PREPARATION OF UREA GRANULES - Google Patents
PROCEDURE FOR THE PREPARATION OF UREA GRANULES Download PDFInfo
- Publication number
- NO151648B NO151648B NO811697A NO811697A NO151648B NO 151648 B NO151648 B NO 151648B NO 811697 A NO811697 A NO 811697A NO 811697 A NO811697 A NO 811697A NO 151648 B NO151648 B NO 151648B
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- Prior art keywords
- urea
- granules
- superphosphate
- melt
- solution
- Prior art date
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- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 title claims description 49
- 239000004202 carbamide Substances 0.000 title claims description 49
- 239000008187 granular material Substances 0.000 title claims description 43
- 238000000034 method Methods 0.000 title claims description 13
- 239000000395 magnesium oxide Substances 0.000 claims description 15
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 7
- 239000010459 dolomite Substances 0.000 claims description 5
- 229910000514 dolomite Inorganic materials 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 239000000155 melt Substances 0.000 claims description 3
- 239000012530 fluid Substances 0.000 claims description 2
- 238000012421 spiking Methods 0.000 claims 1
- 239000002426 superphosphate Substances 0.000 description 22
- YYRMJZQKEFZXMX-UHFFFAOYSA-N calcium;phosphoric acid Chemical compound [Ca+2].OP(O)(O)=O.OP(O)(O)=O YYRMJZQKEFZXMX-UHFFFAOYSA-N 0.000 description 20
- 239000000203 mixture Substances 0.000 description 11
- 238000005469 granulation Methods 0.000 description 8
- 230000003179 granulation Effects 0.000 description 8
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 6
- 238000002425 crystallisation Methods 0.000 description 6
- 230000008025 crystallization Effects 0.000 description 6
- 239000003337 fertilizer Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 239000000428 dust Substances 0.000 description 5
- 239000003112 inhibitor Substances 0.000 description 5
- 239000000654 additive Substances 0.000 description 4
- 230000000996 additive effect Effects 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 229910019142 PO4 Inorganic materials 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 235000021317 phosphate Nutrition 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 2
- 239000010452 phosphate Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- COSWCAGTKRUTQV-UHFFFAOYSA-N 1,1,3-trimethylurea Chemical compound CNC(=O)N(C)C COSWCAGTKRUTQV-UHFFFAOYSA-N 0.000 description 1
- 239000005696 Diammonium phosphate Substances 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 description 1
- 229910000387 ammonium dihydrogen phosphate Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001506 calcium phosphate Substances 0.000 description 1
- ZBZJARSYCHAEND-UHFFFAOYSA-L calcium;dihydrogen phosphate;hydrate Chemical compound O.[Ca+2].OP(O)([O-])=O.OP(O)([O-])=O ZBZJARSYCHAEND-UHFFFAOYSA-L 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- MNNHAPBLZZVQHP-UHFFFAOYSA-N diammonium hydrogen phosphate Chemical compound [NH4+].[NH4+].OP([O-])([O-])=O MNNHAPBLZZVQHP-UHFFFAOYSA-N 0.000 description 1
- 229910000388 diammonium phosphate Inorganic materials 0.000 description 1
- 235000019838 diammonium phosphate Nutrition 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 1
- 235000019837 monoammonium phosphate Nutrition 0.000 description 1
- 239000006012 monoammonium phosphate Substances 0.000 description 1
- 229910000150 monocalcium phosphate Inorganic materials 0.000 description 1
- 238000005453 pelletization Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000037452 priming Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000005029 sieve analysis Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05C—NITROGENOUS FERTILISERS
- C05C9/00—Fertilisers containing urea or urea compounds
- C05C9/005—Post-treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2/00—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
- B01J2/30—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic using agents to prevent the granules sticking together; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05B—PHOSPHATIC FERTILISERS
- C05B19/00—Granulation or pelletisation of phosphatic fertilisers, other than slag
- C05B19/02—Granulation or pelletisation of phosphatic fertilisers, other than slag of superphosphates or mixtures containing them
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Fertilizers (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
- Medicinal Preparation (AREA)
Description
For fremstilling av urea-granuler et det kjent For the production of urea granules it is known
forskjellige fremgangsmåter. En av disse er prilling, hvormed det i det foreliggende menes en fremgangsmåte hvor en hovedsake- different procedures. One of these is prilling, by which in the present case is meant a method where a main
lig vannfri ureasmelte (med et vanninnhold på ikke over 0,1-0,3 equal to anhydrous urea melt (with a water content of no more than 0.1-0.3
vekt%) utsprøytes i den øvre del av et prilletårn i en oppover-rettet luftstrøm av omgivelsestemperatur, i hvilken de små dråper størkner. De resulterende prills har en maksimal diameter på weight%) is sprayed into the upper part of a priming tower in an upwardly directed airflow of ambient temperature, in which the small droplets solidify. The resulting prills have a maximum diameter of
ikke meget over 3 mm og har en heller liten mekanisk styrke. not much over 3 mm and has rather little mechanical strength.
Urea-granuler med større dimensjoner og bedre mekaniske egenskaper kan fremstilles ved granulering av en hovedsakelig vannfri ureasmelte i en trommelgranulator, for eksempel ved den kuledannelsesteknikk som er beskrevet i britisk patent nr. Urea granules with larger dimensions and better mechanical properties can be produced by granulating a substantially anhydrous urea melt in a drum granulator, for example by the pelletizing technique described in British patent no.
894 773, eller ved hjelp av en tallerkengranulator, for eksempel som beskrevet i U.S. patent nr. 4 008 064, eller ved granulering av en vandig ureaoppløsning i et hvirvelskikt, for eksempel som beskrevet i nederlandsk patent nr. 173714. Ved den prosess som er beskrevet i sistnevnte publikasjon, blir en vandig ureaoppløsning med en urea-konsentrasjon på 70-99,9 894,773, or using a plate granulator, for example as described in U.S. Pat. patent no. 4 008 064, or by granulating an aqueous urea solution in a fluidized bed, for example as described in Dutch patent no. 173714. In the process described in the latter publication, an aqueous urea solution with a urea concentration of 70 -99.9
vekt%, fortrinnsvis 85-96 vekt%, sprøytet i form av meget fine dråper med en gjennomsnittlig diameter på 20-120 ym inn i et hvirvelskikt av urea-partikler ved en temperatur ved hvilken vannet fordamper fra den oppløsning som sprøytes på partiklene, % by weight, preferably 85-96% by weight, sprayed in the form of very fine droplets with an average diameter of 20-120 µm into a fluidized bed of urea particles at a temperature at which the water evaporates from the solution sprayed onto the particles,
og urea størkner på partiklene under dannelse av granuler med en ønsket størrelse, som kan være 25 mm eller mer. Da det i denne prosess dannes relativt store mengder av flyvestøv, and urea solidifies on the particles to form granules of a desired size, which may be 25 mm or more. As relatively large amounts of flying dust are formed in this process,
spesielt hvis den som utgangsmateriale anvendte ureaoppløsning inneholder mer enn 5 vekt% vann, mer spesielt over 10 vekt% especially if the urea solution used as starting material contains more than 5% by weight of water, more especially more than 10% by weight
vann, tilsettes det fortrinnsvis et krystallisasjonshemmende middel for urea, spesielt en vannoppløselig tilsetning eller kondensasjonsprodukt av formaldehyd og urea, til ureaoppløs- water, a crystallization inhibiting agent for urea, in particular a water-soluble additive or condensation product of formaldehyde and urea, is preferably added to the urea solution
ningen, hvorved dannelsen av flyvestøv undertrykkes praktisk talt fullstendig. Resultatet av nærværet av det krystallisasjonshemmende middel er at granulene forblir plastiske slik de er ved dannelsen, slik at det på grunn av rulling og/eller sammenstøt under dannelsen kan erholdes mekanisk sterke, glatte og runde granuler. ning, whereby the formation of flying dust is practically completely suppressed. The result of the presence of the crystallization inhibitor is that the granules remain plastic as they are during formation, so that due to rolling and/or impact during formation, mechanically strong, smooth and round granules can be obtained.
De resulterende granuler har høy knusestyrke, stor motstands-dyktighet mot støt og liten tendens til dannelse av flyve- The resulting granules have a high crushing strength, high impact resistance and little tendency to form flying
støv ved abrasjon, og ennvidere klumper eller kaker de seg ikke sammen, ikke engang ved lengre tids lagring, skjønt urea oppviser en sterk naturlig tendens til sammenkaking. dust by abrasion, and furthermore they do not clump or cake together, not even during long storage, although urea exhibits a strong natural tendency to cake.
Urea-granuler fremstilt i henhold til en av de kjente fremgangsmåter kan ikke anvendes for fremstilling av heterogene binære og ternære gjødningsblandinger, så som N-P eller N-P-K-blandinger ved bulk-blanding med det billige superfosfat eller trippel-superfosfat, da slike urea-granuler er uforenlige med disse fosfater. Blandinger av slike urea-granuler med superfosfat- eller trippel-superfosfat-granuler blir flytende etter noen tid og danner en uhåndterlig og ubrukelig gjørme. Ifølge et foredrag av G. Hoffmeister og G.H. Megar, fremført under "The Fertilizer Industry Round Table" den 6. november 19 75 i Washington D.C., skyldes denne uforenlighet en reaksjon som følger: Urea granules produced according to one of the known methods cannot be used for the production of heterogeneous binary and ternary fertilizer mixtures, such as N-P or N-P-K mixtures by bulk mixing with the cheap superphosphate or triple superphosphate, as such urea granules are incompatible with these phosphates. Mixtures of such urea granules with superphosphate or triple superphosphate granules liquefy after some time and form an unmanageable and unusable mud. According to a lecture by G. Hoffmeister and G.H. Megar, presented at "The Fertilizer Industry Round Table" on November 6, 1975 in Washington D.C., this incompatibility is due to a reaction as follows:
Ved reaksjon mellom 1 mol monokalsiumfosfat-monohydrat, som er hovedbestanddelen i superfosfat og trippelsuperfosfat, med 4 mol urea dannes et urea-monokalsiumfosfat-addukt under avgi-velse av 1 mol vann. Da adduktet har en høy oppløselighet, opp-løses det lett i det frigjorte vann under dannelse av et stort volum av oppløsning, som væter granulene i blandingen, med den følge at reaksjonen forløper med enda større hastighet. Opp til nå er det ikke blitt funnet noe kommersielt akseptablet middel som gjør urea forenlig med superfosfat eller trippelsuperfosfat. Av denne grunn er det praktisk talt bare de mer kostbare fosfat-gjødninger monoammoniumfosfat og diammoniumfosfat som kan anvendes for bulk-blanding med urea. When 1 mol of monocalcium phosphate monohydrate, which is the main component in superphosphate and triple superphosphate, reacts with 4 mol of urea, a urea-monocalcium phosphate adduct is formed with the release of 1 mol of water. As the adduct has a high solubility, it dissolves easily in the released water, forming a large volume of solution, which wets the granules in the mixture, with the result that the reaction proceeds at an even greater rate. Up to now, no commercially acceptable agent has been found to make urea compatible with superphosphate or triple superphosphate. For this reason, practically only the more expensive phosphate fertilizers monoammonium phosphate and diammonium phosphate can be used for bulk mixing with urea.
Det er et formål med den foreliggende oppfinnelse å til-veiebringe en fremgangsmåte til fremstilling av urea-granuler med ekstraordinære egenskaper, herunder forenlighet med superfosfat- og trippelsuperfosfat-granuler. It is an aim of the present invention to provide a method for the production of urea granules with extraordinary properties, including compatibility with superphosphate and triple superphosphate granules.
Fremgangsmåten ifølge oppfinnelsen er angitt i kravet, The method according to the invention is stated in the claim,
og det vises til dette. and this is referred to.
Det er overraskende blitt funnet at granuler fremstilt ifølge oppfinnelsen er forenlige med superfosfat- og trippel-superfosf at-granuler , hvilket gjør dem egnet for bulk-blanding med disse fosfatgjødninger. Blandinger av urea-granuler som er fremstilt ifølge oppfinnelsen, og superfosfat-granuler eller trippel-superfosfat-granuler som ble underkastet "TVA Bottle Test" (nærmere omtalt nedenfor) ved 2 7° C var fremdeles tørre etter 7 uker, mens analoge blandinger med urea-granuler som ikke var fremstilt i henhold til oppfinnelsen, var blitt fullstendig flytende etter 3 dager. It has surprisingly been found that granules produced according to the invention are compatible with superphosphate and triple-superphosphate granules, which makes them suitable for bulk mixing with these phosphate fertilizers. Mixtures of urea granules prepared according to the invention and superphosphate granules or triple superphosphate granules subjected to the "TVA Bottle Test" (discussed in more detail below) at 27°C were still dry after 7 weeks, while analogous mixtures with urea granules not prepared according to the invention had completely liquefied after 3 days.
Det er videre blitt funnet at nærværet av magnesiumoksyd under prillingen eller granuleringen av en urea-smelte eller -oppløsning resulterer i at oppbyggingen av granulene forløper feilfritt, og dannelsen av flyvestøv hindres, og de resulterende urea-granuler har dessuten en meget høy knusestyrke og en meget høy tilsynelatende spesifikk vekt. Et ytterligere meget overraskende trekk er at urea-granulene som erholdes ifølge oppfinnelsen, ikke pakker seg sammen, ikke engang etter lengre tids lagring. It has further been found that the presence of magnesium oxide during the prilling or granulation of a urea melt or solution results in the build-up of the granules proceeding flawlessly, and the formation of flying dust is prevented, and the resulting urea granules also have a very high crushing strength and a very high apparent specific gravity. A further very surprising feature is that the urea granules obtained according to the invention do not pack together, not even after longer storage.
Magnesiumoksydet kan anvendes som sådant (MgO) eller i form av fullstendig kalsinert dolomitt (MgO + CaO) eller i form av selektivt kalsinert dolomitt (MgO + CaCO^). En gunstig virkning observeres allerede med en additivmengde tilsvarende 0,1 vekt% MgO, beregnet på vekten av urea i smeiten eller oppløsningen. Fortrinnsvis anvendes additivet i en mengde tilsvarende 0,5-2 vekt% MgO, beregnet på vekten av urea i smeiten eller oppløs-ningen. Om det ønskes, kan høyere andeler anvendes, men dette gir ikke noen spesielle fordeler. Additivet kan tilsettes i form av et pulver til urea-smelten eller -oppløsningen før prillingen eller granuleringen. The magnesium oxide can be used as such (MgO) or in the form of completely calcined dolomite (MgO + CaO) or in the form of selectively calcined dolomite (MgO + CaCO^). A beneficial effect is already observed with an additive amount corresponding to 0.1% by weight of MgO, calculated on the weight of urea in the melt or solution. The additive is preferably used in an amount corresponding to 0.5-2% MgO by weight, calculated on the weight of urea in the melt or solution. If desired, higher proportions can be used, but this does not offer any special advantages. The additive can be added in the form of a powder to the urea melt or solution prior to prilling or granulation.
Etter at granulene er dannet, blir de fortrinnsvis kjølt til 30°C eller til en lavere temperatur, eksempelvis ved hjelp av en luftstrøm, hvis vanninnhold fortrinnsvis er blitt redusert i sådan grad at granulene ikke absorberer fuktighet fra kjøle-luften under kjø\eprosessen. After the granules have been formed, they are preferably cooled to 30°C or to a lower temperature, for example by means of an air stream, the water content of which has preferably been reduced to such an extent that the granules do not absorb moisture from the cooling air during the cooling process.
Som nevnt kan urea-granuler fremstilt ved fremgangsmåten ifølge oppfinnelsen blandes med superfosfat- eller trippel-superfosf at-granuler og eventuelt et eller flere andre granulære stof-fer. i tillegg til urea og superfosfat eller trippel-superfosfat blir for det meste en kaliumgjødning inkludert i blandingen, As mentioned, urea granules produced by the method according to the invention can be mixed with superphosphate or triple superphosphate granules and possibly one or more other granular substances. in addition to urea and superphosphate or triple-superphosphate, a potassium fertilizer is mostly included in the mixture,
så som KC1. For å hindre segregering av blandingen må granul-dimensjonene av de bestanddeler som skal blandes, tilpasses hverandre. such as KC1. To prevent segregation of the mixture, the granule dimensions of the components to be mixed must be adapted to each other.
For ytterligere informasjon vedrørende fremstilling av gjødningsgranuler vises til U.S. patent nr. 3 130 225 når det gjelder prilling, U.S.patent nr. 4 008 064 når det gjelder granulering på tallerkengranulator, britisk patent nr. 894 773 For further information regarding the manufacture of fertilizer granules refer to U.S. Patent No. 3,130,225 as to prilling, U.S. Patent No. 4,008,064 as to granulation on plate granulator, British Patent No. 894,773
når det gjelder granulering i trommelgranulator og til nederlandsk patentsøknad nr. 78.06213 når det gjelder granulering i hvirvelskikt. as regards granulation in a drum granulator and to Dutch patent application No. 78.06213 as regards granulation in a fluidized bed.
Effekten av fremgangsmåten ifølge foreliggende oppfinnelse vil fremgå av de følgende eksempler. Den "TVA Bottle Test" som er nevnt i eksemplene, tjener til å bestemme forenligheten mellom urea-granuler og superfosfat- og trippel-superfosfat-granuler. The effect of the method according to the present invention will be apparent from the following examples. The "TVA Bottle Test" mentioned in the examples serves to determine the compatibility of urea granules with superphosphate and triple superphosphate granules.
I denne test ble en blanding av de urea-granuler som skulle ut-prøves og superfosfat- eller trippel-superfosfat-granuler holdt i en lukket flaske med et volum på 12 0 cm^ ved 2 7°C, og til-standen ble undersøkt periodisk. Den observerte tilstand evalueres som følger: In this test, a mixture of the urea granules to be tested and superphosphate or triple superphosphate granules was kept in a closed bottle with a volume of 120 cm 2 at 27°C, and the condition was examined periodic. The observed condition is evaluated as follows:
Blandingens tilstand The state of the mixture
D = tørr, frittløpende D = dry, free-flowing
W-l = stedvis fuktighet, men anvendbar W-l = wetness in places, but usable
W-2 = fuktig og noe klebende, men sannsynligvis anvendbar W-2 = moist and somewhat sticky, but probably usable
W-3 = gjennomvåt og klebende, uegnet for anvendelse W-3 = soaked and sticky, unsuitable for use
W-4 = meget våt, uegnet for anvendelse W-4 = very wet, unsuitable for use
H = hardt, sammenbaket, uegnet for anvendelse H = hard, caked together, unsuitable for use
I den "sekketest" som er nevnt i eksemplene, ble de undersøkte granulers sammenbakningstendens bestemt. I denne test ble urea-granuler pakket i sekker på 35 kg, som ble lagret under en vekt på 1000 kg ved 27°C. Etter en måned ble det gjennom-snittlige antall klum<p>er pr. sekk bestemt, og klumpenes gjennom-snittlige hardhet ble målt. Med hardhet menes her den kraft i kg, målt ved hjelp av et dynanometer, som er påkrevet for å In the "bag test" mentioned in the examples, the caking tendency of the investigated granules was determined. In this test, urea granules were packed in 35 kg bags, which were stored under a weight of 1000 kg at 27°C. After one month, the average number of clumps per sack determined, and the average hardness of the lumps was measured. Hardness here means the force in kg, measured using a dynamometer, which is required to
knuse en klump på 7 x 7 x 5 cm. crush a lump of 7 x 7 x 5 cm.
Det krystallisasjonshemmende middel F 80 som er nevnt i eksemplene, er en klar viskøs væske som er kommersielt tilgjen-gelig under navnet "Formurea 80", er stabil mellom -20°C og The crystallization inhibitor F 80 mentioned in the examples is a clear viscous liquid which is commercially available under the name "Formurea 80", is stable between -20°C and
+40°C og som ifølge analyse inneholder, pr. 100 vektdeler, +40°C and which, according to analysis, contains, per 100 parts by weight,
ca. 20 vektdeler vann, ca. 23 vektdeler urea og ca. 57 vektdeler formaldehyd, hvor ca. 55% av formaldehydet er bundet som trimetylurea, mens resten foreligger i ubundet tilstand. about. 20 parts by weight water, approx. 23 parts by weight urea and approx. 57 parts by weight of formaldehyde, where approx. 55% of the formaldehyde is bound as trimethylurea, while the rest exists in an unbound state.
Eksempel I Example I
Forsøk ble utført i hvilke en vandig ureaoppløsning med og uten et kjent krystallisasjonshemmende middel (F 80) og med magnesiumoksyd som krystallisasjonshemmende middel ble inn-sprøytet i et hvirvelskikt av ureapartikler. Granuleringsbetingelsene og de resulterende granulers fysikalske egenskaper er angitt i tabell A. Experiments were carried out in which an aqueous urea solution with and without a known crystallization inhibitor (F 80) and with magnesium oxide as crystallization inhibitor was injected into a fluid bed of urea particles. The granulation conditions and the physical properties of the resulting granules are given in Table A.
Eksempel II Example II
En påfølgende forsøksserie ble utført analogt med forsøkene A subsequent series of experiments was carried out analogously to the experiments
i eksempel I, men under anvendelse av selektivt kalsinert dolomitt og fullstendig kalsinert dolomitt som krystallisasjonshemmende middel i stedet for magnesiumoksyd. Granuleringsbetingelsene og de resulterende granulers fysikalske egenskaper er angitt i tabell B. in Example I, but using selectively calcined dolomite and fully calcined dolomite as crystallization inhibitor instead of magnesium oxide. The granulation conditions and the physical properties of the resulting granules are given in Table B.
Eksempel III. Example III.
En hovedsakelig vannfri ureasmelte med og uten tilsatt magnesiumoksyd ble innsprøytet i den øvre del av et prilletårn i en oppadrettet luftstrøm av omgivelsestemperatur. De resulterende prills hadde fysikalske egenskaper som angitt i tabell C. An essentially anhydrous urea melt with and without added magnesium oxide was injected into the upper part of a prilling tower in an upward air stream of ambient temperature. The resulting prills had physical properties as indicated in Table C.
Eksempel IV Example IV
En urea-smelte til hvilken magnesiumoksyd var blitt tilsatt, A urea melt to which magnesium oxide had been added,
ble granulert i en roterende, horisontal granuleringstrommel med en diameter på 90 cm og en bredde på 60 cm. Trommelen var på sin innervegg forsynt med 8 langsgående remser på 3,5 x 6 0 cm an- was granulated in a rotating, horizontal granulating drum with a diameter of 90 cm and a width of 60 cm. The drum was provided on its inner wall with 8 longitudinal strips measuring 3.5 x 60 cm.
ordnet i like store avstander fra hverandre. Hastigheten var 15 omdreininger pr. minutt. Trommelen ble påfyllt 60 kg urea-granuler med en gjennomsnittlig diameter på 1,8 mm og en tempe- arranged at equal distances from each other. The speed was 15 revolutions per minute. The drum was filled with 60 kg of urea granules with an average diameter of 1.8 mm and a tempe-
ratur på 80°C. Under anvendelse av to hydrauliske spredere ble 60 kg vannfri urea-smelte (99,8 vekt% urea), til hvilken 0,6 vekt% MgO var blitt tilsatt, og som hadde en temperatur på 140-145°C, sprøytet inn i den roterende trommel med en hastighet på ca. 100 kg/ time over de granuler som drysset ned fra de langsgående remser. Granuleringen ble utført ved 110°C. rate of 80°C. Using two hydraulic spreaders, 60 kg of anhydrous urea melt (99.8 wt% urea), to which 0.6 wt% MgO had been added, and which had a temperature of 140-145°C, was injected into the rotating drum with a speed of approx. 100 kg/hour over the granules that sprinkled down from the longitudinal strips. The granulation was carried out at 110°C.
Ved slutten av forsøket ble granulene kjølt til ca. 30°C og siktet. Produktgranulene hadde en god rundhet og en glatt over-flate. Deres tilsynelatende densitet var 1,288 g/cm"^, og knuse-styrken, diameter 2,5 mm, var 3,5 kg. Flyvestøvdannelsen var 3,9 g/kg. Granulene hadde praktisk talt ingen tendens til sammenbakning. 50/50-blandinger med SSP og med TSP var anvendbare i over 60 dager. Produktets sikteanalyse var som følger: At the end of the experiment, the granules were cooled to approx. 30°C and sifted. The product granules had a good roundness and a smooth surface. Their apparent density was 1.288 g/cm"^ and the crushing strength, diameter 2.5 mm, was 3.5 kg. The fly dust formation was 3.9 g/kg. The granules had practically no tendency to stick together. 50/50- mixtures with SSP and with TSP were usable for over 60 days.The product sieve analysis was as follows:
gjennomsnittlig diameter : 3,0 mm average diameter : 3.0 mm
Claims (1)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL8002912A NL8002912A (en) | 1980-05-20 | 1980-05-20 | METHOD FOR MAKING UREA GRANULES, AND ARTICLES OF FERTILIZER MIXTURES INCLUDED THEREFORE. |
Publications (3)
Publication Number | Publication Date |
---|---|
NO811697L NO811697L (en) | 1981-11-23 |
NO151648B true NO151648B (en) | 1985-02-04 |
NO151648C NO151648C (en) | 1985-05-15 |
Family
ID=19835332
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO811697A NO151648C (en) | 1980-05-20 | 1981-05-19 | PROCEDURE FOR THE PREPARATION OF UREA GRANULES. |
Country Status (28)
Country | Link |
---|---|
JP (1) | JPS6035320B2 (en) |
AT (1) | AT375917B (en) |
BE (1) | BE888842A (en) |
BG (1) | BG49613A3 (en) |
BR (1) | BR8103139A (en) |
CA (1) | CA1157288A (en) |
CS (1) | CS259506B2 (en) |
DD (1) | DD159040A5 (en) |
DE (1) | DE3118454C2 (en) |
EG (1) | EG15440A (en) |
ES (1) | ES8300311A1 (en) |
FI (1) | FI71721C (en) |
FR (1) | FR2482871B1 (en) |
GB (1) | GB2077722B (en) |
GR (1) | GR75604B (en) |
HU (1) | HU184438B (en) |
IE (1) | IE51964B1 (en) |
IN (1) | IN153960B (en) |
IT (1) | IT1136617B (en) |
MX (1) | MX160067A (en) |
NL (2) | NL8002912A (en) |
NO (1) | NO151648C (en) |
PL (1) | PL134458B1 (en) |
PT (1) | PT73053B (en) |
SE (1) | SE446625B (en) |
TR (1) | TR21674A (en) |
YU (1) | YU42568B (en) |
ZA (1) | ZA813280B (en) |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3117542A1 (en) * | 1981-05-04 | 1983-02-10 | Franz Josef Gattys Ingenieurbüro für Chem. Maschinen- und Apparatebau, 6078 Neu-Isenburg | METHOD FOR STABILIZING DEHYDRATED MAGNESIUM CHLORIDE AGAINST RUECK HYDRATION |
DE3223139C2 (en) * | 1981-07-03 | 1985-02-07 | Compagnie Néerlandaise de l'Azote S.A., Bruxelles | Process for the production of fertilizer granules containing urea as a main component |
NL8502838A (en) * | 1985-10-17 | 1987-05-18 | Azote Sa Cie Neerlandaise | METHOD FOR MANUFACTURING UREA AND AMMONIUM SULFATE CONTAINING FERTILIZER GRAINS. |
DE4232567C1 (en) * | 1992-09-29 | 1994-02-10 | Kali & Salz Ag | Granular sulphate fertiliser treatment to prevent dust formation during bulk transformation - comprises spraying with conc. urea soln. |
AU679330B2 (en) * | 1994-02-11 | 1997-06-26 | Incitec Ltd | Granular urea |
AUPM383594A0 (en) * | 1994-02-11 | 1994-03-10 | Incitec Ltd | Granular urea |
DE102005018949A1 (en) | 2005-04-18 | 2006-10-19 | Ami-Agrolinz Melamine International Gmbh | Solid particles production, especially urea particles, from flowable starting material containing e.g. actinium oxide, useful e.g. in catalysts or milling bodies, comprises splitting into droplets and introducing into solidification liquid |
DE102021108187A1 (en) | 2021-03-31 | 2022-10-06 | Skw Stickstoffwerke Piesteritz Gmbh | Granulated pH neutral urea ammonium sulphate fertilizer with urease inhibitor |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB731686A (en) * | 1952-06-25 | 1955-06-15 | Ici Ltd | Improvements in and relating to urea compositions |
GB837163A (en) * | 1958-01-31 | 1960-06-09 | Ici Ltd | Improvements in and relating to urea compositions |
GB1220826A (en) * | 1967-09-13 | 1971-01-27 | Fisons Ltd | Process for the production of particulate urea |
-
1980
- 1980-05-20 NL NL8002912A patent/NL8002912A/en not_active Application Discontinuation
-
1981
- 1981-05-04 NL NL8102191A patent/NL8102191A/en not_active Application Discontinuation
- 1981-05-09 DE DE3118454A patent/DE3118454C2/en not_active Expired
- 1981-05-12 CA CA000377380A patent/CA1157288A/en not_active Expired
- 1981-05-12 IN IN501/CAL/81A patent/IN153960B/en unknown
- 1981-05-12 IE IE1062/81A patent/IE51964B1/en unknown
- 1981-05-12 GR GR64915A patent/GR75604B/el unknown
- 1981-05-14 AT AT0215381A patent/AT375917B/en not_active IP Right Cessation
- 1981-05-15 FR FR8109729A patent/FR2482871B1/en not_active Expired
- 1981-05-15 GB GB8115005A patent/GB2077722B/en not_active Expired
- 1981-05-18 ZA ZA00813280A patent/ZA813280B/en unknown
- 1981-05-19 JP JP56074344A patent/JPS6035320B2/en not_active Expired
- 1981-05-19 YU YU1285/81A patent/YU42568B/en unknown
- 1981-05-19 NO NO811697A patent/NO151648C/en unknown
- 1981-05-19 FI FI811539A patent/FI71721C/en not_active IP Right Cessation
- 1981-05-19 MX MX187383A patent/MX160067A/en unknown
- 1981-05-19 IT IT21817/81A patent/IT1136617B/en active
- 1981-05-19 HU HU811441A patent/HU184438B/en not_active IP Right Cessation
- 1981-05-19 SE SE8103139A patent/SE446625B/en not_active IP Right Cessation
- 1981-05-19 BE BE2/59164A patent/BE888842A/en not_active IP Right Cessation
- 1981-05-19 CS CS813720A patent/CS259506B2/en unknown
- 1981-05-19 PT PT73053A patent/PT73053B/en not_active IP Right Cessation
- 1981-05-20 BG BG52155A patent/BG49613A3/en unknown
- 1981-05-20 BR BR8103139A patent/BR8103139A/en not_active IP Right Cessation
- 1981-05-20 PL PL1981231271A patent/PL134458B1/en unknown
- 1981-05-20 TR TR21674A patent/TR21674A/en unknown
- 1981-05-20 EG EG283/81A patent/EG15440A/en active
- 1981-05-20 ES ES502903A patent/ES8300311A1/en not_active Expired
- 1981-05-20 DD DD81230122A patent/DD159040A5/en not_active IP Right Cessation
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