CN116161882B - Method for preparing low-sulfur low-calcium clinker by using phosphogypsum - Google Patents
Method for preparing low-sulfur low-calcium clinker by using phosphogypsum Download PDFInfo
- Publication number
- CN116161882B CN116161882B CN202310264749.6A CN202310264749A CN116161882B CN 116161882 B CN116161882 B CN 116161882B CN 202310264749 A CN202310264749 A CN 202310264749A CN 116161882 B CN116161882 B CN 116161882B
- Authority
- CN
- China
- Prior art keywords
- low
- sulfur
- calcium
- mixed raw
- phosphogypsum
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
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
- C04B7/24—Cements from oil shales, residues or waste other than slag
- C04B7/243—Mixtures thereof with activators or composition-correcting additives, e.g. mixtures of fly ash and alkali activators
-
- 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
- C04B7/14—Cements containing slag
- C04B7/147—Metallurgical slag
- C04B7/153—Mixtures thereof with other inorganic cementitious materials or other activators
-
- 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
- C04B7/36—Manufacture of hydraulic cements in general
-
- 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
- C04B7/36—Manufacture of hydraulic cements in general
- C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
- C04B7/44—Burning; Melting
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Processing Of Solid Wastes (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
本发明提供了一种利用磷石膏制备低硫低钙熟料的方法，属于无机材料技术领域。本发明提供的利用磷石膏制备低硫低钙熟料的方法，包括以下步骤：(1)将磷石膏、硅质原材料、铁铝矫正料和碳质原材料混合后得到混合生料；(2)将所述步骤(1)得到的混合生料依次进行预热、预分解和氧化烧成，得到低硫低钙熟料。实施例的结果显示，本发明提供的低硫低钙熟料通过碳化养护2h后抗压强度≥51MPa，抗折强度≥10MPa，碳化养护24h后抗压强度≥79MPa，抗折强度≥15MPa。The present invention provides a method for preparing low-sulfur and low-calcium clinker using phosphogypsum, and belongs to the technical field of inorganic materials. The method for preparing low-sulfur and low-calcium clinker using phosphogypsum provided by the present invention comprises the following steps: (1) mixing phosphogypsum, siliceous raw materials, iron-aluminum corrective materials and carbonaceous raw materials to obtain a mixed raw material; (2) preheating, pre-decomposing and oxidizing the mixed raw material obtained in step (1) in sequence to obtain low-sulfur and low-calcium clinker. The results of the embodiment show that the low-sulfur and low-calcium clinker provided by the present invention has a compressive strength of ≥51MPa and a flexural strength of ≥10MPa after carbonization curing for 2h, and a compressive strength of ≥79MPa and a flexural strength of ≥15MPa after carbonization curing for 24h.
Description
Technical Field
The invention relates to the technical field of inorganic materials, in particular to a method for preparing low-sulfur and low-calcium clinker by using phosphogypsum.
Background
Phosphoric acid plays a great role as an industrial product in the fields of agriculture, chemical industry, food, medicine and the like, and the supply of phosphoric acid is a basic folk of China, but a large amount of industrial waste, mainly phosphogypsum, is generated in the process of preparing phosphoric acid by an industrial wet method. Phosphogypsum mainly comprises calcium sulfate dihydrate, and compared with natural gypsum and industrial gypsum, phosphogypsum contains a large amount of substances such as organic phosphorus, fluoride, silicon dioxide, organic matters and the like. On the one hand, the substances cause the phosphogypsum to have serious environmental hazard, on the other hand, the performance of the dihydrate gypsum in the phosphogypsum is seriously affected, and finally, the recycling of the phosphogypsum becomes a difficult problem. The phosphogypsum can be recycled on a large scale and can be treated on a large scale.
The development of the resource utilization of phosphogypsum in the field of building materials is a reliable path capable of realizing large-scale treatment of phosphogypsum, and various difficulties are faced in preparing clinker by using phosphogypsum at present. When phosphogypsum is used for preparing ordinary silicate cement clinker, a large amount of SO 3 and SO 2 are generated, and SO 3 and SO 2 can seriously influence the generation of tricalcium silicate (C 3 S), SO that the hydration performance of the clinker is finally influenced, and the consumption of the phosphogypsum for preparing sulphoaluminate cement clinker is limited. In order to avoid the influence of SO 3 and SO 2 on the formation of clinker mineral phases, the prior technical scheme adopts a technical scheme that the raw materials are completely decomposed into CaSO 4 before entering a kiln, the technical scheme is usually realized by improving the decomposition temperature, and the overall preparation energy consumption of the clinker is inevitably improved, SO that the oxidation and sintering cost is greatly improved, for example, a patent CN 115108744A is provided with a double decomposing furnace to completely decompose CaSO 4, the prior equipment is required to be greatly transformed, and meanwhile, the decomposition energy consumption is obviously improved due to the overhigh temperature of a second oxidizing furnace. The low-calcium clinker does not contain C 3 S, and can obtain higher mechanical properties after carbonization and maintenance, so that the low-calcium clinker is an ideal environment-friendly material capable of large-scale absorption of phosphogypsum. However, the production of the material also faces the limitation on the desulfurization rate of phosphogypsum, if the desulfurization rate is increased in the pre-decomposition stage, the technology which is the same as that of the existing cement clinker production is adopted, the high-cost and high-requirement process can be faced, and the reduction of the decomposition rate can generate the sulfur silicate mineral to reduce the content of carbonizable components, so that the performance of the low-calcium clinker is finally affected. There is a need to develop a method for preparing low-sulfur low-calcium clinker with phosphogypsum, which has low energy consumption and excellent mechanical properties.
Disclosure of Invention
The invention aims to provide a method for preparing low-sulfur low-calcium clinker by using phosphogypsum, which has the advantages of lower decomposition temperature and low energy consumption, and the prepared low-sulfur low-calcium clinker has excellent compressive strength and flexural strength.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a method for preparing low-sulfur and low-calcium clinker by phosphogypsum, which comprises the following steps:
(1) Mixing phosphogypsum, siliceous raw materials, iron-aluminum correction materials and carbonaceous raw materials to obtain mixed raw materials;
(2) And (3) preheating, pre-decomposing and oxidizing and sintering the mixed raw material obtained in the step (1) in sequence to obtain the low-sulfur and low-calcium clinker.
Preferably, the siliceous raw materials in the step (1) comprise one or more of sandstone, shale, silica, desert sand, siliceous tailings and clay, the ferroaluminum correction material comprises one or more of bauxite, iron powder, steel slag and red mud, and the carbonaceous raw materials comprise one or more of coal dust, coke and biomass fuel.
Preferably, in the step (1), when the molar ratio of calcium to silicon in the mixed raw material is 1.0-1.8, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is less than or equal to 6%, when the molar ratio of calcium to silicon in the mixed raw material is 1.8-2.6, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is less than or equal to 10%, and when the molar ratio of calcium to silicon in the mixed raw material is 2.6-3.0, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is 10% -20%.
Preferably, the mixed raw material in step (1) has an average particle size of <300 μm.
Preferably, the temperature of the preheating in the step (2) is more than or equal to 750 ℃.
Preferably, the temperature of the pre-decomposition in the step (2) is 850-1000 ℃.
Preferably, the temperature of the oxidation firing in the step (2) is 1200-1400 ℃, and the time of the oxidation firing is 0.5-2 h.
Preferably, the SO 3 content in the low-sulfur and low-calcium clinker in the step (2) is less than or equal to 1wt%.
The invention provides the low-sulfur low-calcium clinker prepared by the method.
Preferably, the total amount of CS, C 3S2 and C 2 S in the low-sulphur low-calcium clinker is >50% by mass.
The invention provides a method for preparing low-sulfur and low-calcium clinker by phosphogypsum, which comprises the following steps:
(1) Mixing phosphogypsum, siliceous raw materials, iron-aluminum correction materials and carbonaceous raw materials to obtain mixed raw materials, and (2) sequentially preheating, pre-decomposing and oxidizing-sintering the mixed raw materials obtained in the step (1) to obtain the low-sulfur and low-calcium clinker. The method utilizes the characteristic that the mineral phase of the high-carbonization-activity low-calcium clinker is not easily influenced by SO 3 in the oxidation firing process, the CaSO 4 is decomposed into two steps to be respectively subjected to pre-decomposition and oxidation firing, the temperature of the pre-decomposition process is greatly reduced, the energy consumption of the pre-decomposition is reduced, the process involved in the preparation process can be carried out by using the existing equipment, an additional oxidation-decomposition furnace is not required, only an atmosphere control related device is required to be additionally arranged, the method is easy to realize in actual industrial production, the existing cement industrial equipment is not required to be greatly modified, the process flow is simple, phosphogypsum can be greatly absorbed by the preparation method, the difficult problem of disposal of phosphogypsum is solved, and the prepared high-carbonization-activity low-calcium clinker has extremely high mechanical property after carbonization maintenance for 24 hours and is an environment-friendly material with wide application scene. The results of the examples show that the compressive strength of the low-sulfur and low-calcium clinker provided by the invention is more than or equal to 51MPa after carbonization and maintenance for 2 hours, the flexural strength is more than or equal to 10MPa, and the compressive strength is more than or equal to 79MPa after carbonization and maintenance for 24 hours, and the flexural strength is more than or equal to 15MPa.
Detailed Description
The invention provides a method for preparing low-sulfur and low-calcium clinker by phosphogypsum, which comprises the following steps:
(1) Mixing phosphogypsum, siliceous raw materials, iron-aluminum correction materials and carbonaceous raw materials to obtain mixed raw materials;
(2) And (3) preheating, pre-decomposing and oxidizing and sintering the mixed raw material obtained in the step (1) in sequence to obtain the low-sulfur and low-calcium clinker.
The invention mixes phosphogypsum, siliceous raw materials, iron-aluminum correction materials and carbonaceous raw materials to obtain mixed raw materials.
In the present invention, the phosphogypsum, siliceous raw material, iron-aluminum rectification material and carbonaceous raw material are preferably pretreated separately before use. In the present invention, the pretreatment includes drying, crushing and pulverizing treatments performed sequentially. In the invention, the temperature of the drying is preferably 100-105 ℃, more preferably 105 ℃, and the water content of the dried product is preferably less than or equal to 5 wt%. In the present invention, the particle size of the product after the grinding treatment is preferably <1mm. The method can remove moisture by preprocessing the raw materials, and simultaneously reduce the particle size of the raw materials, thereby being beneficial to the subsequent mixing with other raw materials.
In the invention, the CaO content in phosphogypsum is preferably more than 30 wt%, the siliceous raw materials preferably comprise one or more of sandstone, shale, silica, desert sand, siliceous tailings and clay, the ferroaluminum correction materials preferably comprise one or more of bauxite, iron powder, steel slag and red mud, and the carbonaceous raw materials preferably comprise one or more of coal dust, coke and biomass fuel. The specific sources of the siliceous raw materials, the iron-aluminum correction materials and the carbonaceous raw materials are not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used.
The invention preferably also incorporates a calcareous raw material, preferably comprising one or more of limestone, slaked lime and carbide slag, more preferably limestone or slaked lime, preferably >90wt.% CaO in the chemical composition after 950 ℃ burn-out. The invention adopts calcareous raw materials as supplementary raw materials, and mainly aims to correct calcareous components of phosphogypsum so as to facilitate batching.
In the invention, when the molar ratio of calcium and silicon in the mixed raw material is preferably 1.0-1.8, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is preferably less than or equal to 6%, when the molar ratio of calcium and silicon in the mixed raw material is 1.8-2.6, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is preferably less than or equal to 10%, and when the molar ratio of calcium and silicon in the mixed raw material is 2.6-3.0, the total mass fraction of Al 2O3 and Fe 2O3 in the mixed raw material is preferably 10% -20%. According to the invention, by controlling the molar ratio of calcium and silicon of the raw materials and the contents of Al 2O3 and Fe 2O3, the formation of a proper mineral phase in the subsequent process can be ensured, so that the performance of the clinker is improved.
In the present invention, the mixing means is preferably grinding. In the present invention, the average particle size of the mixed raw material is preferably <300 μm. The specific operation of the grinding is not particularly limited, and the particle size of the mixed raw material can meet the requirement.
After the mixed raw material is obtained, the mixed raw material is sequentially preheated, pre-decomposed and oxidized and burned to obtain the low-sulfur and low-calcium clinker.
In the present invention, the temperature of the preheating is preferably at least 750 ℃. The mixed raw material is preheated, so that the mixed raw material is favorable for subsequent pre-decomposition treatment.
In the invention, the temperature of the pre-decomposition is preferably 850-1000 ℃, more preferably 900-950 ℃, the pre-decomposition is preferably carried out in a reducing atmosphere, the volume fraction of O 2 in the pre-decomposition atmosphere is preferably <3vol%, the volume fraction of CO is preferably >3vol%, and the pre-decomposition atmosphere is preferably controlled by adjusting the air quantity and injecting pulverized coal. In the present invention, the content of CaSO 4 in the pre-decomposed product is preferably <3wt.%. According to the invention, by controlling the temperature and atmosphere of pre-decomposition, part of CaSO 4 in phosphogypsum can be decomposed into CaO and SO 3, SO that the quality of clinker is improved, and meanwhile, the decomposition temperature is low, and the energy consumption can be reduced.
In the present invention, the pre-decomposition is preferably performed in a decomposing furnace. The specific model of the decomposing furnace is not particularly limited, and commercially available products known to those skilled in the art may be used.
In the invention, the temperature of the oxidation firing is preferably 1200-1400 ℃, more preferably 1250-1350 ℃, further preferably 1300 ℃, and the time of the oxidation firing is preferably 0.5-2 h, more preferably 1-1.5 h. In the present invention, the atmosphere for the oxidative firing is preferably an oxidizing atmosphere, and the concentration of oxygen in the oxidizing atmosphere is preferably >5vol%. According to the invention, by controlling the parameters of the oxidation sintering, the non-decomposed CaSO 4 can further form a C 5S2 $mineral phase in the oxidation sintering process, so that the performance of the low-sulfur and low-calcium clinker is further improved.
In the present invention, the oxidation firing is preferably performed in a rotary kiln. The specific model of the rotary kiln is not particularly limited, and commercially available products known to those skilled in the art can be used.
The specific operation of grinding is not particularly limited, and the average particle size of the low-sulfur and low-calcium clinker can meet the requirement. In the present invention, the average particle size of the low sulfur low calcium clinker is <150 μm. The invention can further improve the mechanical property of the low-sulfur and low-calcium clinker by controlling the particle size of the low-sulfur and low-calcium clinker.
In the invention, the content of SO 3 in the low-sulfur low-calcium clinker is preferably less than or equal to 1wt%.
The method utilizes the characteristic that the mineral phase of the high-carbonization-activity low-calcium clinker is not easily influenced by SO 3 in the oxidation firing process, the CaSO 4 is decomposed into two steps to be respectively subjected to pre-decomposition and oxidation firing, the temperature of the pre-decomposition process is greatly reduced, the energy consumption of the pre-decomposition is reduced, the process involved in the preparation process can be carried out by using the existing equipment, an additional oxidation-decomposition furnace is not required, only an atmosphere control related device is required to be additionally arranged, the method is easy to realize in actual industrial production, the existing cement industrial equipment is not required to be greatly modified, the process flow is simple, phosphogypsum can be greatly absorbed by the preparation method, the difficult problem of disposal of phosphogypsum is solved, and the prepared high-carbonization-activity low-calcium clinker has extremely high mechanical property after carbonization maintenance for 24 hours and is an environment-friendly material with wide application scene.
The invention provides the low-sulfur low-calcium clinker prepared by the method.
In the present invention, the total amount of CS, C 3S2 and C 2 S in the low-sulfur low-calcium clinker is >50% by mass. The invention can make the low-sulfur low-calcium clinker have excellent mechanical properties by controlling the chemical composition of the clinker.
The technical solutions of the present invention will be clearly and completely described in the following in connection with the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
A method for preparing low-sulfur and low-calcium clinker by phosphogypsum comprises the following steps:
(1) Respectively drying, crushing and grinding phosphogypsum, siliceous raw materials, ferroaluminum correction materials and carbonaceous raw materials in sequence, and then mixing and grinding to obtain mixed raw materials, wherein the drying temperature is 105 ℃, the particle size of the product after grinding is less than 1mm, the water content of the mixed raw materials is less than or equal to 5 wt%, the siliceous raw materials are siliceous tailings, the ferroaluminum correction materials are bauxite, the carbonaceous raw materials are coal dust, the mass ratio of the phosphogypsum, siliceous raw materials, the ferroaluminum correction materials to the carbonaceous raw materials is 79:18:4:9, and the average particle size of the mixed raw materials is less than 300 mu m;
(2) Preheating the mixed raw material obtained in the step (1) to 750 ℃, pre-decomposing in a decomposing furnace, oxidizing and firing in a rotary kiln, and grinding when cooling to below 55 ℃ to obtain low-sulfur and low-calcium clinker, wherein the pre-decomposing temperature is 900 ℃, the volume fraction of O 2 in the pre-decomposing atmosphere is less than 2vol%, the volume fraction of CO is 6vol%, the content of CaSO 4 in the pre-decomposed product is less than 3 wt%, the oxidizing and firing temperature is 1300 ℃, the oxidizing and firing time is 0.5h, the oxidizing and firing atmosphere is an oxidizing atmosphere, and the volume fraction of O 2 in the oxidizing atmosphere is 10vol%.
1.35 Tons of phosphogypsum can be consumed per 1 ton of clinker prepared in example 1.
The main chemical composition of the different raw materials pretreated in example 1 was analyzed by XRF test, and the results are shown in table 1:
Table 1 main chemical composition (wt.%) of different raw materials
| LOI | CaO | SiO2 | Al2O3 | Fe2O3 | SO3 | |
| Phosphogypsum | 3.285 | 37.550 | 4.921 | 0.556 | 0.543 | 48.812 |
| Siliceous tailings | 2.336 | 4.731 | 76.431 | 9.114 | 2.605 | 0.028 |
| Iron-aluminum correction material | 12.500 | 4.200 | 16.700 | 61.000 | 0.172 | 0.089 |
The chemical composition of the mixed raw material obtained in step (1) of example 1 is shown in table 2:
Table 2 chemical composition (wt.%) of the mixed raw meal obtained in example 1
The composition of the low sulfur and low calcium clinker prepared in example 1 was analyzed by XRD full spectrum fitting quantitative analysis, wherein C 2 S is the sum of various different crystal forms C 2 S such as β -C 2S、γ-C2S、α-C2 S, SO 3 was measured by X-ray fluorescence detection, and f-CaO was measured according to the method of cement chemistry analysis (GB/T176-2017), and the results obtained are shown in table 3:
Table 3 composition (wt.%) of the low sulfur low calcium clinker prepared in example 1
Application example 1
The low-sulfur low-calcium clinker prepared in example 1 and water are mixed according to a mixing ratio of 0.15, and then carbonized and cured to obtain a sample, and the compressive strength and the flexural strength of the sample are tested, wherein the compressive strength of the sample is a cylinder with the size of phi 20mm by 20mm, the flexural strength of the sample is a cuboid with the size of 37.5 by 6.5 by 6.8mm, the carbonized and cured atmosphere is 99% CO 2, the air pressure is 0.3MPa, the curing temperature is room temperature, the strength test loading rate is 200N/s, and the test results are shown in table 4:
TABLE 4 physical Properties of Low Sulfur Low calcium Clinker
Example 2
A method for preparing low-sulfur and low-calcium clinker by phosphogypsum comprises the following steps:
(1) Respectively drying, crushing and grinding phosphogypsum, siliceous raw materials, ferroaluminum correction materials and carbonaceous raw materials in sequence, and then mixing and grinding to obtain mixed raw materials, wherein the drying temperature is 105 ℃, the particle size of the product after grinding is less than 1mm, the water content of the mixed raw materials is less than or equal to 5 wt%, the siliceous raw materials are siliceous tailings, the ferroaluminum correction materials are bauxite, the carbonaceous raw materials are coal dust, the mass ratio of the phosphogypsum, the siliceous raw materials, the ferroaluminum correction materials to the carbonaceous raw materials is 77.8:21:1.2:9, and the average particle size of the mixed raw materials is less than 300 mu m;
(2) Preheating the mixed raw material obtained in the step (1) to 750 ℃, pre-decomposing in a decomposing furnace, oxidizing and firing in a rotary kiln, and grinding when cooling to below 55 ℃ to obtain low-sulfur and low-calcium clinker, wherein the pre-decomposing temperature is 900 ℃, the volume fraction of O 2 in the pre-decomposing atmosphere is less than 2vol%, the volume fraction of CO is 6vol%, the content of CaSO 4 in the pre-decomposed product is less than 3 wt%, the oxidizing and firing temperature is 1300 ℃, the oxidizing and firing time is 0.5h, the oxidizing and firing atmosphere is an oxidizing atmosphere, and the volume fraction of O 2 in the oxidizing atmosphere is 10vol%.
1.34 Tons of phosphogypsum can be consumed per 1 ton of clinker prepared in example 2.
The main chemical composition of the different raw materials pretreated in example 2 was analyzed by XRF test, and the results are shown in table 5:
table 5 main chemical composition (wt.%) of different raw materials
| LOI | CaO | SiO2 | Al2O3 | Fe2O3 | SO3 | |
| Phosphogypsum | 3.285 | 37.550 | 4.921 | 0.556 | 0.543 | 48.812 |
| Siliceous tailings | 1.650 | 1.041 | 88.772 | 5.393 | 1.166 | 0.070 |
| Iron-aluminum correction material | 12.500 | 4.200 | 16.700 | 61.000 | 0.172 | 0.089 |
The chemical composition of the mixed raw material obtained in step (1) of example 2 is shown in Table 6:
Table 6 chemical composition (wt.%) of the mixed raw meal obtained in example 2
| LOI | CaO | SiO2 | Al2O3 | Fe2O3 | SO3 | |
| Mixed raw material | 3.048 | 29.474 | 22.714 | 2.278 | 0.668 | 37.981 |
The composition of the low sulfur and low calcium clinker prepared in example 1 was analyzed by XRD full spectrum fitting quantitative analysis, wherein C 2 S is the sum of various different crystal forms C 2 S such as β -C 2S、γ-C2S、α-C2 S, SO 3 was measured by X-ray fluorescence detection, and f-CaO was measured according to the method of cement chemistry analysis (GB/T176-2017), and the results obtained are shown in table 7:
Table 7 composition (wt.%) of the low sulfur low calcium clinker prepared in example 2
Application example 2
The low-sulfur low-calcium clinker prepared in example 2 and water are mixed according to a mixing ratio of 0.15, and then carbonized and cured to obtain a sample, and the compressive strength and the flexural strength of the sample are tested, wherein the compressive strength of the sample is a cylinder with the size of phi 20mm by 20mm, the flexural strength of the sample is a cuboid with the size of 37.5 by 6.5 by 6.8mm, the carbonized and cured atmosphere is 99% CO 2, the air pressure is 0.3MPa, the curing temperature is room temperature, the strength test loading rate is 200N/s, and the test results are shown in table 8:
TABLE 8 physical Properties of Low Sulfur Low calcium Clinker
Example 3
A method for preparing low-sulfur and low-calcium clinker by phosphogypsum comprises the following steps:
(1) The phosphogypsum, the calcareous raw material, the siliceous raw material, the iron aluminum rectifying material and the carbonaceous raw material are respectively and sequentially dried, crushed and ground, mixed grinding is carried out to obtain mixed raw material, the drying temperature is 105 ℃, the particle size of a product obtained after the grinding treatment is less than 1mm, the water content of the mixed raw material is less than or equal to 5 wt%, the siliceous raw material is siliceous tailings, the calcareous raw material is limestone, the iron aluminum rectifying material is bauxite, the carbonaceous raw material is coal dust, the mass ratio of the phosphogypsum, the siliceous raw material, the iron aluminum rectifying material to the carbonaceous raw material is 55.7:5.0:8.4:5.1:8.2, and the average particle size of the mixed raw material is less than 300 mu m;
(2) Preheating the mixed raw material obtained in the step (1) to 750 ℃, pre-decomposing in a decomposing furnace, oxidizing and firing in a rotary kiln, and grinding when cooling to below 55 ℃ to obtain low-sulfur and low-calcium clinker, wherein the pre-decomposing temperature is 900 ℃, the volume fraction of O 2 in the pre-decomposing atmosphere is less than 2vol%, the volume fraction of CO is 6vol%, the content of CaSO 4 in the pre-decomposed product is less than 3 wt%, the oxidizing and firing temperature is 1300 ℃, the oxidizing and firing time is 0.5h, the oxidizing and firing atmosphere is an oxidizing atmosphere, and the volume fraction of O 2 in the oxidizing atmosphere is 10vol%.
1.32 Tons of phosphogypsum can be consumed per 1 ton of clinker prepared in example 3.
The main chemical composition of the different raw materials pretreated in example 3 was analyzed by XRF test and the results are shown in table 9:
Table 9 main chemical composition (wt.%) of different raw materials
| LOI | CaO | SiO2 | Al2O3 | Fe2O3 | SO3 | |
| Phosphogypsum | 3.285 | 37.550 | 4.921 | 0.556 | 0.543 | 48.812 |
| Limestone powder | 41.800 | 50.501 | 2.210 | 0.762 | 0.397 | 0.105 |
| Siliceous tailings | 2.336 | 4.731 | 76.431 | 9.114 | 2.605 | 0.028 |
| Red mud | 10.001 | 2.468 | 13.241 | 27.559 | 40.192 | 0.673 |
Example 3 the chemical composition of the mixed raw meal obtained in step (1) is shown in table 10:
table 10 chemical composition (wt.%) of the mixed raw meal obtained in example 3
| LOI | CaO | SiO2 | Al2O3 | Fe2O3 | SO3 | |
| Mixed raw material | 6.235 | 32.296 | 13.406 | 3.395 | 3.492 | 36.698 |
The composition of the low sulfur and low calcium clinker prepared in example 1 was analyzed by XRD full spectrum fitting quantitative analysis, wherein C 2 S is the sum of various different crystal forms C 2 S such as β -C 2S、γ-C2S、α-C2 S, SO 3 was measured by X-ray fluorescence detection, and f-CaO was measured according to the method of cement chemistry analysis (GB/T176-2017), and the results obtained are shown in table 11:
Table 11 composition (wt.%) of the low sulfur low calcium clinker prepared in example 3
Application example 3
The low-sulfur low-calcium clinker prepared in example 3 and water are mixed according to a mixing ratio of 0.15, and then carbonized and cured to obtain a sample, and the compressive strength and the flexural strength of the sample are tested, wherein the compressive strength of the sample is a cylinder with the size of phi 20mm by 20mm, the flexural strength of the sample is a cuboid with the size of 37.5 by 6.5 by 6.8mm, the carbonized and cured atmosphere is 99% CO 2, the air pressure is 0.3MPa, the curing temperature is room temperature, the strength test loading rate is 200N/s, and the test results are shown in table 12:
TABLE 12 physical Properties of Low Sulfur Low calcium Clinker
As can be seen from application examples 1-3, the compressive strength of the sample obtained from the low-sulfur low-calcium clinker prepared by the invention is more than or equal to 51MPa after carbonization and maintenance for 2 hours, the flexural strength is more than or equal to 10MPa, the compressive strength after carbonization and maintenance for 24 hours is more than or equal to 79MPa, the flexural strength is more than or equal to 15MPa, and the sample has excellent physical properties, and meanwhile, more than 1.3 tons of phosphogypsum can be consumed per ton of low-sulfur low-calcium clinker produced in the process of preparing the low-sulfur low-calcium clinker.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310264749.6A CN116161882B (en) | 2023-03-20 | 2023-03-20 | Method for preparing low-sulfur low-calcium clinker by using phosphogypsum |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310264749.6A CN116161882B (en) | 2023-03-20 | 2023-03-20 | Method for preparing low-sulfur low-calcium clinker by using phosphogypsum |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116161882A CN116161882A (en) | 2023-05-26 |
| CN116161882B true CN116161882B (en) | 2025-01-10 |
Family
ID=86414707
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310264749.6A Active CN116161882B (en) | 2023-03-20 | 2023-03-20 | Method for preparing low-sulfur low-calcium clinker by using phosphogypsum |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116161882B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117486509A (en) * | 2023-10-31 | 2024-02-02 | 华新水泥股份有限公司 | Method for cooperatively treating phosphogypsum and preparing low-carbon clinker by using inferior coal |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114644466A (en) * | 2022-04-07 | 2022-06-21 | 武汉理工大学 | Method for preparing low-calcium self-pulverization clinker and co-producing sulfuric acid by using phosphogypsum |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105129744B (en) * | 2015-07-21 | 2017-10-20 | 湖北湖大天沭新能源材料工业研究设计院有限公司 | A kind of method that ardealite Sulphuric acid co-producing cement is thermally decomposed in advance |
| EP3199500A1 (en) * | 2016-01-29 | 2017-08-02 | Cimsa Cimento Sanayi Ve Ticaret Anonim Sirketi | Calcium sulphoaluminate cement with mayenite phase |
| CN108892401B (en) * | 2018-08-23 | 2020-12-01 | 天津水泥工业设计研究院有限公司 | Method for calcining belite sulphoaluminate cement clinker by using phosphogypsum and cement clinker |
| DE102020100254A1 (en) * | 2020-01-08 | 2021-07-08 | Thyssenkrupp Ag | Integrated process for the production of a building material from phosphogypsum |
| CN112661426B (en) * | 2020-12-30 | 2022-06-07 | 山东大学 | A kind of sulfur aluminum iron series cement, its preparation method, system and its application in marine engineering materials |
| CN112694067A (en) * | 2020-12-30 | 2021-04-23 | 成都千砺金科技创新有限公司 | Production method for co-producing cement and sulfuric acid by using phosphogypsum |
| CN115093135B (en) * | 2022-07-13 | 2023-04-14 | 华新水泥股份有限公司 | Process for preparing belite sulphoaluminate cement clinker by phosphogypsum desulfurization |
| CN115286266B (en) * | 2022-08-19 | 2023-04-11 | 武汉理工大学 | Carbon-negative clinker prepared from phosphogypsum and preparation method of carbon-negative clinker |
-
2023
- 2023-03-20 CN CN202310264749.6A patent/CN116161882B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114644466A (en) * | 2022-04-07 | 2022-06-21 | 武汉理工大学 | Method for preparing low-calcium self-pulverization clinker and co-producing sulfuric acid by using phosphogypsum |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116161882A (en) | 2023-05-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101003422B (en) | New method for producing sulfuric acid and cement by using phosphogypsum | |
| CN109970378B (en) | Preparation process of solid waste base gelling material based on synergistic theory and carbonization/high temperature technology | |
| WO2018166220A1 (en) | Method for co-producing sulphoaluminate cement and sulfur by using desulfurized gypsum and aluminum ash | |
| CN101041449A (en) | Method for extracting aluminium oxide from coal ash and producing cement by using waste slag | |
| CN116375365B (en) | Method for preparing low-calcium clinker through phosphogypsum desulfurization | |
| CN113354311A (en) | Resource-saving low-carbon cement clinker and preparation method thereof | |
| CN115180846B (en) | Process for preparing calcium sulphoaluminate modified portland cement clinker by phosphogypsum desulfurization | |
| CN107056100A (en) | A kind of preparation method of clinker | |
| CN108129041A (en) | Utilize the preparation method of oil base well drilling detritus burning silicate cement clinker | |
| CN106365477A (en) | Method for preparing high-strength sulphoaluminate cement and coproducing sulfuric acid | |
| CN102020251B (en) | Improved production process for preparing sulfuric acid and cement from gypsum | |
| CN116161882B (en) | Method for preparing low-sulfur low-calcium clinker by using phosphogypsum | |
| CN101323436B (en) | A method for reducing and decomposing phosphogypsum by using a composite reducing agent | |
| CN115286266B (en) | Carbon-negative clinker prepared from phosphogypsum and preparation method of carbon-negative clinker | |
| CN116395994B (en) | Method for preparing Gao Tanhua active cementing material through phosphogypsum desulfurization | |
| CN102530886A (en) | Method for preparing sulfuric acid and cement by using phosphogypsum | |
| CN112624646A (en) | Concrete admixture | |
| CN115093135B (en) | Process for preparing belite sulphoaluminate cement clinker by phosphogypsum desulfurization | |
| CN116553842A (en) | High-magnesium low-carbon cement clinker and preparation method thereof | |
| CN101318631B (en) | Method and apparatus for decomposing phosphogypsum to produce sulphuric acid, generating electricity power and cement with quiescent state reduction | |
| CN115108744A (en) | Process for decomposing phosphogypsum and co-producing cement | |
| CN106630703A (en) | Method for preparing high-strength sulfate aluminum cement co-production sulfuric acid through calcining by steps | |
| CN100369850C (en) | A method for comprehensive utilization of coal gangue and phosphogypsum | |
| CN107162447A (en) | A kind of method that utilization carbide slag prepares clinker | |
| CN116282988B (en) | Method for preparing low-calcium solid carbon gel material by using phosphogypsum |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |