US3194673A - Hydraulic cement and process for making same - Google Patents
Hydraulic cement and process for making same Download PDFInfo
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- US3194673A US3194673A US135408A US13540861A US3194673A US 3194673 A US3194673 A US 3194673A US 135408 A US135408 A US 135408A US 13540861 A US13540861 A US 13540861A US 3194673 A US3194673 A US 3194673A
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- 238000000034 method Methods 0.000 title claims description 17
- 239000011396 hydraulic cement Substances 0.000 title claims description 4
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 38
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 27
- 239000000203 mixture Substances 0.000 claims description 20
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 18
- 239000004568 cement Substances 0.000 claims description 17
- 239000000377 silicon dioxide Substances 0.000 claims description 13
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 6
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 6
- 239000004571 lime Substances 0.000 claims description 6
- AGWMJKGGLUJAPB-UHFFFAOYSA-N aluminum;dicalcium;iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Al+3].[Ca+2].[Ca+2].[Fe+3] AGWMJKGGLUJAPB-UHFFFAOYSA-N 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 47
- 229910052742 iron Inorganic materials 0.000 description 23
- 239000000463 material Substances 0.000 description 22
- 229960005191 ferric oxide Drugs 0.000 description 15
- 235000013980 iron oxide Nutrition 0.000 description 15
- 235000019738 Limestone Nutrition 0.000 description 13
- 229910001570 bauxite Inorganic materials 0.000 description 13
- 239000006028 limestone Substances 0.000 description 13
- 238000004519 manufacturing process Methods 0.000 description 11
- 239000000843 powder Substances 0.000 description 11
- 238000005054 agglomeration Methods 0.000 description 6
- 230000002776 aggregation Effects 0.000 description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 4
- 239000004567 concrete Substances 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 4
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 4
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 4
- 229960004029 silicic acid Drugs 0.000 description 4
- 235000012239 silicon dioxide Nutrition 0.000 description 4
- 239000000654 additive Substances 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 238000005272 metallurgy Methods 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- 239000002893 slag Substances 0.000 description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 2
- 239000011398 Portland cement Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 150000004645 aluminates Chemical class 0.000 description 2
- -1 aluminum compound Chemical class 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 235000012241 calcium silicate Nutrition 0.000 description 2
- 229910052918 calcium silicate Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000000571 coke Substances 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 229910052595 hematite Inorganic materials 0.000 description 2
- 239000011019 hematite Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 238000004131 Bayer process Methods 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 239000011449 brick Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 229940043430 calcium compound Drugs 0.000 description 1
- 150000001674 calcium compounds Chemical class 0.000 description 1
- JHLNERQLKQQLRZ-UHFFFAOYSA-N calcium silicate Chemical compound [Ca+2].[Ca+2].[O-][Si]([O-])([O-])[O-] JHLNERQLKQQLRZ-UHFFFAOYSA-N 0.000 description 1
- 239000000378 calcium silicate Substances 0.000 description 1
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 description 1
- WETINTNJFLGREW-UHFFFAOYSA-N calcium;iron;tetrahydrate Chemical compound O.O.O.O.[Ca].[Fe].[Fe] WETINTNJFLGREW-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 239000003818 cinder Substances 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 210000003608 fece Anatomy 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 229910021646 siderite Inorganic materials 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
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
- C04B7/00—Hydraulic cements
- C04B7/32—Aluminous cements
-
- 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
- C04B7/00—Hydraulic cements
- C04B7/22—Iron ore cements ; Iron rich cements, e.g. Ferrari cements, Kühl cements
Definitions
- This invention relates to a process for agglomerating iron ores as well as for preparing hydraulic binding material usable in structural engineering. Moreover, this invention relates to a process for agglomerating iron powders by the aid of this binding material.
- the agglomerating processes known and used hitherto can be divided into two groups.
- the ore powder is agglomerated with the aid of pressure, with or without a binding material.
- the most important obstacle to the general use of the cold agglomerating process is the lack of a suitable binding material.
- a suitable binding material For briquetting iron ores, an inexpensive, quick setting and rapidly solidifying binding material having an adequately high strength is necessary.
- the binder must contain no contaminants harmful from the iron-metallurgy point of view, or must contain any such contaminant only in small amounts.
- the Portland cements or Portland slag cements can be used for this purpose only to a very limited degree because, on the one hand they have a high silicic-acid content, and on the other hand, they set and, solidify slowly 4-6 hours), so that the briquettes do not have sufiicient strength to stand up to the stresses of treatment and the transport even after several hours.
- the present process is based on the discovery that from most of the iron ores to be smelted a hydraulic binding material satisfying the above requirements can be produced if an aluminum compound and a calcium com- 'ice pound (e.g. bauxite and limestone) are added in a quantity depending on the composition of the impurity.
- a calcium com- 'ice pound e.g. bauxite and limestone
- a hydraulic binding material suitable for agglomerating iron ores and usable for construction is produced according to the invention by calcinating a mixture of compounds containing lime and/0r aluminum with a crude, enriched or calcinated ore containing iron, in a manner known in the manufacture of cement, to cement clinkers, then producing from it a mixed comminuted product with addition to limestone to limestone or some other material for adjusting the setting time.
- the individual additive agents can be used in such ratio that, in the finished cement clinker, the quantity of the aluminum oxide and iron oxide is higher than twice the silicic-acid content, and the amount of the aluminum oxide is, at the maximum, one-and-a-half times greater than that of the iron oxide.
- the agglomeration of the by-products, droppings, alloying elements and other iron-containing additives used in the production of iron and steel can be accomplished with the aid of the hydraulic binding material described above.
- carbon (coke, coal etc.) can be added to the agglomerated ore.
- the mixture thus obtained may be ground to a fineness on the order of that employed in the cement industry and then can be sintered in a rotary furnace.
- the hydraulic binding material is obtained after adding limestone in a quantity ranging from 1 to 5% by weight or adding some other material capable of regulating the setting time.
- This composition is characterized by the fact that the silicate ratio (SiO /Al O H-Fe O of the binding ma terial is smaller than 0.5 and its aluminate ratio (Al O /Fe O is smaller than 1.5.
- the process according to the invention can be carried out, accordingly, by employing the individual additive agents in such a quantitative ratio that, in the finished cement clinker, the total quantity of aluminum oxide and iron oxide exceeds twice the quantity of silicic acid, and the quantity of aluminum oxide does not exceed 1.5 times the quantity of iron oxide.
- the binding material thus prepared is mixed with the ore to be agglomerated in a quantity depending on the particle size of the ore and is moistened to produce a state corresponding to that of damp soil; then it is pressed into briquettes.
- the resulting ore concrete can be transported after two hours, and can be fed after 24 hours into a blast furnace or an open-hearth furnace.
- the fine ore powders can be agglomerated also by pelleting, whereby the mixture of moistened ore powder and the binding material is formed into balls in a rotary drum, or by rolling the pulverulent mixture on a tray.
- the process according to the invention renders possible the production of a cheap binding material, because, on the one hand, the binding material is produced from the iron ore which anyway would be fed into the furnace, and, on the other hand, the quantity of the limestone to be supplied additionally to the furnace can be In Table 2 the quantities of the individual components necessary for the production of the binding material are given.
- C AF represents tetracalcium alumino-ferrite (Ca Al Fe O C 1 CS and (3 8 are calcium ferrite, calcium silicate and dicalcium silicate, respectively;
- a further advantage of the process is that bauxites having an alumina/ silica ratio (Al O /siO smaller than 5 and not usable in the Bayer process for the production of aluminum can be employed for cement production; this raw material is available in very large, unmarketable quantities in the waste heaps of bauxite mines. Additionally, in the furnace any iron content of the bauxite is utilized while the aluminun1-oxide content of the bauxite improves the blast-furnace cinder. The feeding of good-quality bauxite is reasonable only in case of ores having a high content of free silicic acid.
- the powdery ore can be easily screened, that part of the powder which has a particle size smaller than 1 mm. is utilized to reduce the expense of grinding. Thanks to the high iron-oxide content of the raw material, the sintering can be carried-out at temperatures not exceeding 1300" C.
- the result of the low sintcring temperature is that the output of the rotary furnace (or, alternatively, a shaft or cupola furnace) increases as compared to the yield of a cement furnace, for sintering Portland-cement clinker at a temperature of about 1750 C. so that the heat-energy requirement of the bat;- ing is lower.
- the process according to the invention canbe employed also in other fields, such as in structural engineer ing, mining or deep drilling.
- iron-ore types are suitable for the production of this binding material but it can be'produced at the lowest cost from basic iron ores containing calcium and only a small quantity of iron.
- compositions of eight dii'ferent iron ores, of a good bauxite having an alumina/silica ratio greater than 5 and a poor bauxite having an alumina/sil tions of the iron ores are identical with those given in Table 1.
- Table 2 p 7 3 [Composition of the raw material, percent by Weight] Bauxite Ore Limestone Good Bad Table 3 5'0 [Composition of the binding material, percent by weight] SiO A1 0 l e- O; CaO Balance (impurities) 4. 62 1s. 25 2s. 00' .46. so 2. 33 7. 82 16. 80 25.00 48. 30 2. 08 6. 75 17. 62 20. 25 47. 1. 78 8.17 17.15 26.30 46. 60 1. 78 6.25 17.18 25.88 47. "2/94 12. 05 12. 20. 90 48. 83 5. 27 7.05 10. 00 25.10 48. 70 3.15 8. 45 W 15.28 23.30 46.80 6.17
- a mixture consisting of 18.4% of iron ore from Krivoj- Rog, 17.6% of bauxite of poor quality and 64% of limestone is baked. In order to increase and render uniform the setting time, 4% of limestone is added and the whole mass is ground to the fineness of cement.
- the breaking strength of a concrete composed of the material thus obtained amounted after 24 hours to 145 kg./crn. after 7.days to 350 kg./cm. and after 28 days to 469 kg./cm.
- a process for producing a hydraulic cement comprising the steps of admixing lime, silica, alumina and iron oxide, the weight ratio of the silica content to the sum of the alumina and iron oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron oxide content being less than about 1.5; heating the resulting mixture at a temperature suflicient to convert same into a cement clinker consisting in major part of a tetra-calcium alumino-ferrite; comminuting the clinker thus produced; and admixing with the comminuted clinker a substance capable of modifying the setting rate of the cement.
- a process for producing a hydraulic cement comprising the steps of admixing lime, silica, alumina and iron oxide to produce a mixture, said mixture consisting by weight substantially of 4 to 12% silica, 8 to 21% alumina, 13 to 33% iron oxide, and to lime, the Weight ratio of the silica content to the sum of the alumina and iron oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron-oxide content being less than about 1.5; heating the resulting mixture at a temperature sufiicient to form a cement clinker therefrom, and comminuting the clinker thus produced.
- a sintered cement consisting substantially of 4 to 12% silica, 8 to 21% alumina, 13 to 33% iron oxide and 40 to 50% lime, the weight ratio of the silica content to the sum of the alumina and iron-oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron-oxide content being less than about 1.5.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
United States Patent 3,194,673 HYDRAULHI CEMENT AND PROCE FQR MAKING SAME Andor Schedel, Budapest, Hungary, assignor to Licencia Talalrnanyolrat Ertekesito Vallalat, Budapest, Hungary No Drawing. Filed Aug. 29, 1961, Ser. No. 135,408 3 Claims. (Cl. 106-166) This invention relates to a process for agglomerating iron ores as well as for preparing hydraulic binding material usable in structural engineering. Moreover, this invention relates to a process for agglomerating iron powders by the aid of this binding material.
It is generally known that lumpy ores having the high iron content necessary for ferrous-metal metallurgy are being depleted; therefore the ferrous-metal industry is compelled to use powdery ores and to enrich such ores having a relatively low iron content.
These iron-ore powders cannot be fed directly into blast-furnaces because part of the powdery mass would be carried away by the blast air and because they would pack together and cause channeling in the blast furnaces. Open-hearth furnaces cannot be fed with refining ore powders either, because these powders would be carried away by the stack gases, and part of these powders would penetrate into the heat-resistant lining of the furnace, thereby rendering the lining fusible.
The agglomerating processes known and used hitherto can be divided into two groups.
(a) During thermal agglomeration the ore powders are mixed with coke powder and burned until the particles are sintered, or pellets, bricks and/or briquettes are pressed formed from the ore powder and then these bodies are baked.
(b) During cold agglomeration, the ore powder is agglomerated with the aid of pressure, with or without a binding material.
Shrinking agglomeration (Dwight-Lloyd, Greenewalt etc. processes) is economical for blast-furnace ores only where the necessary coke powder is available as in inexpensive waste material and is not economical for aggloriierating the refining ores necessary for steel production because it reduces part of the Fe O content of the ore to FeO so that the employment of the refining ore in a larger quantity becomes necessary. The apparent density of ore sintered in this way is usually lower than that of the open-hearth slag; consequently it floats on the surface of the slag and is less readily refinable.
The most important obstacle to the general use of the cold agglomerating process is the lack of a suitable binding material. For briquetting iron ores, an inexpensive, quick setting and rapidly solidifying binding material having an adequately high strength is necessary. The binder must contain no contaminants harmful from the iron-metallurgy point of view, or must contain any such contaminant only in small amounts. The Portland cements or Portland slag cements can be used for this purpose only to a very limited degree because, on the one hand they have a high silicic-acid content, and on the other hand, they set and, solidify slowly 4-6 hours), so that the briquettes do not have sufiicient strength to stand up to the stresses of treatment and the transport even after several hours.
The present process is based on the discovery that from most of the iron ores to be smelted a hydraulic binding material satisfying the above requirements can be produced if an aluminum compound and a calcium com- 'ice pound (e.g. bauxite and limestone) are added in a quantity depending on the composition of the impurity.
A hydraulic binding material suitable for agglomerating iron ores and usable for construction is produced according to the invention by calcinating a mixture of compounds containing lime and/0r aluminum with a crude, enriched or calcinated ore containing iron, in a manner known in the manufacture of cement, to cement clinkers, then producing from it a mixed comminuted product with addition to limestone to limestone or some other material for adjusting the setting time.
According to the invention the individual additive agents can be used in such ratio that, in the finished cement clinker, the quantity of the aluminum oxide and iron oxide is higher than twice the silicic-acid content, and the amount of the aluminum oxide is, at the maximum, one-and-a-half times greater than that of the iron oxide.
The agglomeration of the by-products, droppings, alloying elements and other iron-containing additives used in the production of iron and steel can be accomplished with the aid of the hydraulic binding material described above.
According to the invention, carbon (coke, coal etc.) can be added to the agglomerated ore.
It is advantageous to add the bauxite and the limestone in a quantity varying within the limits calculated on a stoichiometrical basis. The mixture thus obtained may be ground to a fineness on the order of that employed in the cement industry and then can be sintered in a rotary furnace. The hydraulic binding material is obtained after adding limestone in a quantity ranging from 1 to 5% by weight or adding some other material capable of regulating the setting time.
It is advantageous to establish the quantity of the iron ore, aluminum and calcium compounds (bauxite and limestone) so that the composition of the baked clinker remains within the following values:
Percent SiO 4-12 A1 0 8-21 Fe 0 13-33 CaO 4050 This composition is characterized by the fact that the silicate ratio (SiO /Al O H-Fe O of the binding ma terial is smaller than 0.5 and its aluminate ratio (Al O /Fe O is smaller than 1.5. The process according to the invention can be carried out, accordingly, by employing the individual additive agents in such a quantitative ratio that, in the finished cement clinker, the total quantity of aluminum oxide and iron oxide exceeds twice the quantity of silicic acid, and the quantity of aluminum oxide does not exceed 1.5 times the quantity of iron oxide.
The binding material thus prepared is mixed with the ore to be agglomerated in a quantity depending on the particle size of the ore and is moistened to produce a state corresponding to that of damp soil; then it is pressed into briquettes. The resulting ore concrete can be transported after two hours, and can be fed after 24 hours into a blast furnace or an open-hearth furnace. The fine ore powders can be agglomerated also by pelleting, whereby the mixture of moistened ore powder and the binding material is formed into balls in a rotary drum, or by rolling the pulverulent mixture on a tray.
Thus the process of ore agglomeration is, in effect, the production of ore concrete. The expenses of invest-v ment and production are considerably lower than in case of the pyrometallurgical agglomerating processes. A great advantage of the briquetting or pelleting lies in the fact that other components, including even a smaller or larger part of the necessary furnace coke, can be added to the ore to be agglomerated in the form of a cheap coke powder, hence the production of the so-called "furnace-mixture is, in the maiority. of cases, concluded with the agglomeration step.
The process according to the invention renders possible the production of a cheap binding material, because, on the one hand, the binding material is produced from the iron ore which anyway would be fed into the furnace, and, on the other hand, the quantity of the limestone to be supplied additionally to the furnace can be In Table 2 the quantities of the individual components necessary for the production of the binding material are given.
aluminate ratios (Al O /Fe O are shown. The designation C AF represents tetracalcium alumino-ferrite (Ca Al Fe O C 1 CS and (3 8 are calcium ferrite, calcium silicate and dicalcium silicate, respectively;
in Tables 2 to 5, in the first column 'the denominareduced by the amount of limestone added to the binder; thus the expenses connected with the use or" limestone for the binder can be recovered.
A further advantage of the process is that bauxites having an alumina/ silica ratio (Al O /siO smaller than 5 and not usable in the Bayer process for the production of aluminum can be employed for cement production; this raw material is available in very large, unmarketable quantities in the waste heaps of bauxite mines. Additionally, in the furnace any iron content of the bauxite is utilized while the aluminun1-oxide content of the bauxite improves the blast-furnace cinder. The feeding of good-quality bauxite is reasonable only in case of ores having a high content of free silicic acid.
It" the powdery ore can be easily screened, that part of the powder which has a particle size smaller than 1 mm. is utilized to reduce the expense of grinding. Thanks to the high iron-oxide content of the raw material, the sintering can be carried-out at temperatures not exceeding 1300" C. The result of the low sintcring temperature is that the output of the rotary furnace (or, alternatively, a shaft or cupola furnace) increases as compared to the yield of a cement furnace, for sintering Portland-cement clinker at a temperature of about 1750 C. so that the heat-energy requirement of the bat;- ing is lower.
Besides its suitability in the metallurgy of ferrous metals, the process according to the invention canbe employed also in other fields, such as in structural engineer ing, mining or deep drilling.
Most iron-ore types are suitable for the production of this binding material but it can be'produced at the lowest cost from basic iron ores containing calcium and only a small quantity of iron.
In the following tables data concerning the composition of eight known iron ores as well as of the binding material produced from these ores are. summarized.
in Table 1 the compositions of eight dii'ferent iron ores, of a good bauxite having an alumina/silica ratio greater than 5 and a poor bauxite having an alumina/sil tions of the iron ores are identical with those given in Table 1.
Table 1 [Percent by weight] Balance Denomination FezOs S102 A1 0 CaO CO: 1120 (impurities) 1. Magnetite from Kiiruna 80.00 3. 50 2. 24. 9.20 1.07 3. 09 Hematite from Krivoi-Rog (Soviet Union) 74. 30 16.00 2. 87 0. 28 4. 00 2. 55 3. Iron ore from Chattanooga District (U.S.A.) 48. 00 7. 28 3.14 21.40 16. 50 2.14 1. 54 4. Hematite from Alabama (U.S.A.) 48. 00 10. 84 2. 88 19. 73 15.00 2.00 1. 55 5. Siderite from Steyr Erzberg (Austria) 47. 5. 50 1. 57 8. 99 32 69 4.01 6. Iron ore from Salzgittcr Hawerlachwicse (Germany) 10. 30 24. 80 0. 20 4.90 9. 50 7. Basic minette from Anderney (France) 44. 00 8.20 4. 17. 20 3.15 8. Raw iron ore from Oxford (Great Britain) 34.30 10.20 7. 60 12.20 10.10 Bauxite having a good alumina/silica ratio- 18. 50 3. 50 56. 00 0. 5. 00 Bauxite having a poor alumina/silica rati 20.00 10. 00 50.00 V 0.30 9. 60 Limestone- 0.17 0.14 0. 11 54.04 1.29
Table 2 p 7 3 [Composition of the raw material, percent by Weight] Bauxite Ore Limestone Good Bad Table 3 5'0 [Composition of the binding material, percent by weight] SiO A1 0 l e- O; CaO Balance (impurities) 4. 62 1s. 25 2s. 00' .46. so 2. 33 7. 82 16. 80 25.00 48. 30 2. 08 6. 75 17. 62 20. 25 47. 1. 78 8.17 17.15 26.30 46. 60 1. 78 6.25 17.18 25.88 47. "2/94 12. 05 12. 20. 90 48. 83 5. 27 7.05 10. 00 25.10 48. 70 3.15 8. 45 W 15.28 23.30 46.80 6.17
Table .4 [Mineral composition, percent by weight] Balance C AF Ca. C F 028 CS (impurities) 7.45 3.96 1.64 17.00 3.62 1 2.05 12. 50, 4. as 1. s4 10.35 8.15 1. 84 12. 68- 3 56 2.16 27. 55 4 t3 5. 09 20. 55' 3. 25 18.90 3. 64 5 ica ratio (AI O /SiO lower than 5, as well as of a limestone of better quality, are given.
be added for regu- Table 5 [Mineral composition, percent by weight] The process according to the invention is illustrated by the following example.
A mixture consisting of 18.4% of iron ore from Krivoj- Rog, 17.6% of bauxite of poor quality and 64% of limestone is baked. In order to increase and render uniform the setting time, 4% of limestone is added and the whole mass is ground to the fineness of cement.
The breaking strength of a concrete composed of the material thus obtained amounted after 24 hours to 145 kg./crn. after 7.days to 350 kg./cm. and after 28 days to 469 kg./cm.
Upon the addition of 5-6% from the thus-prepared binding material to a powdery iron ore screened on a 2-mm.-mesh screen, the properties of the obtained binding material considerably exceed the requirements of the metallurgical industry.
What I claim is:
1. A process for producing a hydraulic cement, comprising the steps of admixing lime, silica, alumina and iron oxide, the weight ratio of the silica content to the sum of the alumina and iron oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron oxide content being less than about 1.5; heating the resulting mixture at a temperature suflicient to convert same into a cement clinker consisting in major part of a tetra-calcium alumino-ferrite; comminuting the clinker thus produced; and admixing with the comminuted clinker a substance capable of modifying the setting rate of the cement.
2. A process for producing a hydraulic cement, comprising the steps of admixing lime, silica, alumina and iron oxide to produce a mixture, said mixture consisting by weight substantially of 4 to 12% silica, 8 to 21% alumina, 13 to 33% iron oxide, and to lime, the Weight ratio of the silica content to the sum of the alumina and iron oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron-oxide content being less than about 1.5; heating the resulting mixture at a temperature sufiicient to form a cement clinker therefrom, and comminuting the clinker thus produced.
3. A sintered cement consisting substantially of 4 to 12% silica, 8 to 21% alumina, 13 to 33% iron oxide and 40 to 50% lime, the weight ratio of the silica content to the sum of the alumina and iron-oxide contents being less than about 0.5, the weight ratio of the alumina content to the iron-oxide content being less than about 1.5.
References Cited by the Examiner UNITED STATES PATENTS 806,161 12/05 Michaelis 106-100 1,586,099 5/26 Martin 106-100 1,594,178 7/26 Kuhl 106-100 1,994,379 3/35 Williams et al. -3 2,134,103 10/38 Collord 75-3 2,271,276 1/42 Rolfsen 106-100 2,696,432 12/54 Davis 75-5 2,995,438 8/61 Subervie 75-5 OTHER REFERENCES The Chemistry of Cement and Concrete, Lea and Desch, Edward Arnold Ltd., London, 2nd Edition, 1956,
pages 58, 59, and 278.
TOBIAS E. LEVOW, Primary Examiner.
JOSEPH REBOLD, Examiner.
Claims (1)
1. A PROCESS FOR PRODUCING A HYDRAULIC CEMENT, COMPRISING THE STEPS OF ADMIXING LIME, SILICA, ALUMINA AND IRON OXIDE, THE WEIGHT RATIO OF THE SILICA CONTENT TO THE SUM OF THE ALUMINA AND IRON OXIDE CONTENTS BEING LESS THAN ABOUT 0.5, THE WEIGHT RATIO OF THE ALUMINA CONTENT TO THE IRON OXIDE CONTENT BEING LESS THAN BOUT 1.5; HEATING THE RESULTING MIXTURE AT A TEMPERATURE SUFFICIENT TO CONVERT SAME INTO A CEMENT CLINKER CONSISTING IN MAJOR PART OF A TETRA-CALCIUM ALUMINO-FERRITE; COMMINUTING THE CLINKER THUS PRODUCED; AND ADMIXING WITH THE COMMINUTED CLINKER A SUBSTANCE CAPABLE OF MODIFYING THE SETTING RATE OF THE CEMENT.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US135408A US3194673A (en) | 1961-08-29 | 1961-08-29 | Hydraulic cement and process for making same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US135408A US3194673A (en) | 1961-08-29 | 1961-08-29 | Hydraulic cement and process for making same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3194673A true US3194673A (en) | 1965-07-13 |
Family
ID=22467976
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US135408A Expired - Lifetime US3194673A (en) | 1961-08-29 | 1961-08-29 | Hydraulic cement and process for making same |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3194673A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3649316A (en) * | 1968-07-20 | 1972-03-14 | Onoda Cement Co Ltd | Extra high early-strength portland cement |
| US3793036A (en) * | 1971-01-13 | 1974-02-19 | A Grachian | Method of producing rapid-hardening cement |
| US4957556A (en) * | 1989-06-08 | 1990-09-18 | Hassan Kunbargi | Very early setting ultra high early strength cement |
| WO1998030512A1 (en) * | 1997-01-11 | 1998-07-16 | Deutsche Rockwool Mineralwoll-Gmbh | Inorganic binder |
| WO2003082764A1 (en) * | 2002-03-28 | 2003-10-09 | Council Of Scientific And Industrial Research | Process for manufacture of high iron hydraulic cement clinker |
| JP2005521620A (en) * | 2002-03-28 | 2005-07-21 | カウンシル・オブ・サイエンティフィック・アンド・インダストリアル・リサーチ | Method for producing hydraulic iron ore cement clinker |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US806161A (en) * | 1901-03-28 | 1905-12-05 | Fried Krupp Grusonwerk At Magdeburg Buckau | Manufacture of hydraulic cement. |
| US1586099A (en) * | 1924-09-11 | 1926-05-25 | Martin Ernest | Manufacturing process for cements containing iron and alumina combinations |
| US1594178A (en) * | 1924-03-31 | 1926-07-27 | Albert T Otto & Sons | Cement and process of making the same |
| US1994379A (en) * | 1934-01-06 | 1935-03-12 | Battelle Memorial Institute | Iron-bearing briquette and method of making the same |
| US2134103A (en) * | 1937-03-02 | 1938-10-25 | George L Collord | Method of concentrating ores |
| US2271276A (en) * | 1936-02-26 | 1942-01-27 | Rolfsen Ole | Process for producing cement |
| US2696432A (en) * | 1950-12-22 | 1954-12-07 | Univ Minnesota | Method for heating solids |
| US2995438A (en) * | 1958-11-25 | 1961-08-08 | Subervie Georges Michel | Preparation of ores for metallurgical use |
-
1961
- 1961-08-29 US US135408A patent/US3194673A/en not_active Expired - Lifetime
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US806161A (en) * | 1901-03-28 | 1905-12-05 | Fried Krupp Grusonwerk At Magdeburg Buckau | Manufacture of hydraulic cement. |
| US1594178A (en) * | 1924-03-31 | 1926-07-27 | Albert T Otto & Sons | Cement and process of making the same |
| US1586099A (en) * | 1924-09-11 | 1926-05-25 | Martin Ernest | Manufacturing process for cements containing iron and alumina combinations |
| US1994379A (en) * | 1934-01-06 | 1935-03-12 | Battelle Memorial Institute | Iron-bearing briquette and method of making the same |
| US2271276A (en) * | 1936-02-26 | 1942-01-27 | Rolfsen Ole | Process for producing cement |
| US2134103A (en) * | 1937-03-02 | 1938-10-25 | George L Collord | Method of concentrating ores |
| US2696432A (en) * | 1950-12-22 | 1954-12-07 | Univ Minnesota | Method for heating solids |
| US2995438A (en) * | 1958-11-25 | 1961-08-08 | Subervie Georges Michel | Preparation of ores for metallurgical use |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3649316A (en) * | 1968-07-20 | 1972-03-14 | Onoda Cement Co Ltd | Extra high early-strength portland cement |
| US3793036A (en) * | 1971-01-13 | 1974-02-19 | A Grachian | Method of producing rapid-hardening cement |
| US4957556A (en) * | 1989-06-08 | 1990-09-18 | Hassan Kunbargi | Very early setting ultra high early strength cement |
| WO1998030512A1 (en) * | 1997-01-11 | 1998-07-16 | Deutsche Rockwool Mineralwoll-Gmbh | Inorganic binder |
| WO2003082764A1 (en) * | 2002-03-28 | 2003-10-09 | Council Of Scientific And Industrial Research | Process for manufacture of high iron hydraulic cement clinker |
| JP2005521620A (en) * | 2002-03-28 | 2005-07-21 | カウンシル・オブ・サイエンティフィック・アンド・インダストリアル・リサーチ | Method for producing hydraulic iron ore cement clinker |
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