Environment-friendly cement clinker and preparation method thereof

Abstract

The invention provides an environment-friendly cement clinker and a preparation method thereof, and belongs to the technical field of concrete preparation, the environment-friendly cement clinker is prepared from the following raw materials by weight: 82-84 parts of limestone; 7.5 to 8.5 parts of sandstone tailing powder; 1.5 to 2.5 parts of water quenching slag; 1.5 to 2.5 parts of coal burning slag; 4.5 to 5.5 parts of aluminum tailing powder; the content of S O2 in the water-quenched slag is 22 to 28 percent, and the content of A < l > 2O3 in the water-quenched slag is 8.5 to 10.5 percent; the content of CaO is 7.5 to 8.5 percent, and the content of R2O is 0.7 to 0.8 percent; and the content of SO3 is 0.25 to 0.35 percent. The environment-friendly cement clinker prepared by the invention can reduce the material cost, and also has the effects of high breaking strength, high compressive strength and stable setting time.

Description

Technical Field

[0001] The invention relates to the technical field of concrete preparation, and in particular to an environmentally friendly cement clinker and a preparation method thereof. Background Art

[0002] Cement clinker is a semi-finished product obtained by mixing limestone, clay and iron raw materials in appropriate proportions, burning them until they are partially or completely melted, and cooling them. In the cement industry, the most commonly used silicate cement clinker has calcium oxide, silicon dioxide and a small amount of aluminum oxide and iron oxide as its main chemical components. The main mineral components are tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium aluminoferrite. After silicate cement clinker is ground with an appropriate amount of gypsum, it becomes silicate cement.

[0003] With the development of my country's economy, the population tends to be urbanized, and the scale of cities and infrastructure construction are constantly increasing. In the process of construction, the generation of construction waste is bound to be accelerated. The floating dust in the generated construction waste seriously affects the urban environment, such as the pollution of air and water resources, and also causes waste of land resources, greatly affecting the utilization rate of land resources. We make comprehensive use of construction waste resources to replace sandstone tailings powder to prepare environmentally friendly cement clinker, and its product quality and performance meet the requirements of GB 175-2007 "General Portland Cement".

[0004] Therefore, it is necessary to develop a cement clinker that meets the demand. Summary of the invention

[0005] In order to overcome the problems existing in the related art, the purpose of the present invention is to provide an environmentally friendly cement clinker, which can reduce material costs and also has the effects of high flexural strength, high compressive strength and stable setting time.

[0006] An environmentally friendly cement clinker is prepared from the following raw material ratios:

[0007] Limestone 82-84 parts

[0008] Iron tailings powder 2.8-4.2 parts

[0009] 11.5-15.5 parts of construction waste

[0010] The SiO2 content of the construction waste is 56-60%, and the Al2O3 content is 13-15%;

[0011] In a preferred technical solution of the present invention, the CaO content in the construction waste is 8.5-10.5%, R 2 O is 1.8-2.2%;

[0012] R 2 O refers to the alkaline oxide (Na2 O.K 2 O) content;

[0013] In a preferred technical solution of the present invention, the MgO content in the construction waste is 1.8-2.2%;

[0014] In a preferred technical solution of the present invention, the ratio of the construction waste to limestone is 1:(6-7);

[0015] In a preferred technical solution of the present invention, the specific surface area of ​​the environmentally friendly cement clinker is 345-365m 2 / kg, the environmentally friendly cement clinker 0.08mm fineness is 2-2.4%;

[0016] In a preferred technical solution of the present invention, the lime saturation ratio KH in the environmentally friendly cement clinker is 0.88-0.92, the silicon oxygen ratio N is 2.8-3.0, and the aluminum oxygen ratio P is 1.3-1.5;

[0017] In a preferred technical solution of the present invention, the f-CaO in the environmentally friendly cement clinker is ≤1%;

[0018] In a preferred technical solution of the present invention, the initial setting time of the environmentally friendly cement clinker is 110-120 minutes;

[0019] In a preferred technical solution of the present invention, the final setting time of the environmentally friendly cement clinker is 165-180min;

[0020] Another object of the present invention is to provide an environmentally friendly cement clinker preparation method, comprising the following steps:

[0021] S1. Raw material grinding: According to the raw material ratio of environmentally friendly cement clinker, limestone, iron tailings powder and construction waste in the environmentally friendly cement clinker raw materials are added to the raw material roller press for mixing and grinding, and the feed rate is 110-130t / h;

[0022] S2. Clinker calcination: add the ground material into the rotary kiln for calcination, feed rate 80-90t / h, coal powder amount at the kiln head 2.5-3.5t / h, coal powder amount at the kiln tail 5.5-6.5t / h, kiln tail temperature 1000-1100℃, to obtain environmentally friendly cement clinker.

[0023] In a preferred technical solution of the present invention, the coal powder has a fineness of ≤4.0% and a water content of ≤3.0%;

[0024] The beneficial effects of the present invention are:

[0025] The environmentally friendly cement clinker provided by the present invention is mixed in a combination of specific proportions and has the effects of low cost, high flexural strength, high compressive strength and stable setting time. DETAILED DESCRIPTION

[0026] These examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually carried out according to conventional conditions in the art or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets. Any non-substantial changes and substitutions made by those skilled in the art on the basis of the present invention are within the scope of protection claimed by the present invention.

[0027] The raw materials used in the following examples and comparative examples are as follows:

[0028] Raw material roller press: Chengdu Lijun Co., Ltd., model CLF160-80

[0029] Rotary kiln: Chaoyang Heavy Machinery Factory, model Y3250∮3.2×50

[0030] Construction waste: Shaanxi Jincheng Industrial Co., Ltd., Zhen'an County, Shangluo City, Shaanxi Province

[0031] Sandstone tailings powder: Shaanxi Jinpengyou Industry and Trade Co., Ltd., Ankang City, Shaanxi Province

[0032] Table 1: The raw material construction waste was tested according to JC T874-2021 "Chemical Analysis Methods for Siliceous Raw Materials for Cement".

[0033]

[0034] The cement clinkers of Examples 1-5 and Comparative Examples 1-3 were prepared according to the following preparation method:

[0035] S1 raw material grinding: According to the weight ratio of cement clinker raw materials in Table 4 and the comparative example, the raw materials were added to the raw material roller press and mixed and ground, and the feed rate was 110-130t / h;

[0036] S2. Clinker calcination: add the ground material into the rotary kiln for calcination, feed rate 80-90t / h, coal powder amount at the kiln head 2.5-3.5t / h, coal powder amount at the kiln tail 5.5-6.5t / h, kiln tail temperature 1000-1100℃, to obtain environmentally friendly cement clinker.

[0037] in:

[0038] Table 2: Raw material roller press production operating parameters

[0039]

[0040]

[0041] Table 3: Operating parameters for environmentally friendly cement clinker production in rotary kiln

[0042]

[0043] Table 4: Cement clinker proportions by weight of the examples and comparative examples

[0044]

[0045] The environmentally friendly cement clinker prepared in Example 1 and Comparative Example 1 was chemically analyzed according to GB176-2017 and physically tested according to GBT17671-2021 cement mortar strength test method (ISO) and GBT 1346-2011 "cement standard consistency water consumption, setting time, and stability test method":

[0046] Table 5-1: Chemical analysis quality table of environmentally friendly cement clinker of Example 1 and Comparative Example 1

[0047]

[0048] Table 5-2: Chemical analysis quality table of environmentally friendly cement clinker of Example 1 and Comparative Example 1

[0049]

[0050] Table 6: Physical inspection quality table of environmentally friendly cement clinker of Example 1 and Comparative Example 1

[0051]

[0052] The specific surface area, 0.08 mm fineness, setting time and flexural and compressive strength of the cement clinker obtained in Examples 1-5 and Comparative Examples 1-3 were physically tested according to GBT17671-2021 "Test Method for Cement Mortar Strength (ISO)", GBT 1346-2011 "Test Method for Water Consumption, Setting Time and Stability of Cement Standard Consistency", GBT8074-2008 "Method for Determination of Specific Surface Area of ​​Cement - Blaine Method", and GBT1345-2005 "Test Method for Cement Fineness - Sieve Analysis Method".

[0053] Table 7: Test results of Examples 1-5 and Comparative Examples 1-3

[0054]

[0055]

[0056] The cement clinker prepared in the above Example 1 and Comparative Example 1 was mixed with desulfurized gypsum, stone powder and grinding aid in the following proportions to prepare cement, wherein the grinding aid was YB004 enhanced grinding aid produced by Shangluo Yaobai Xiushan Cement Co., Ltd.;

[0057] Table 8: Cement clinker proportions by weight for the examples and comparative examples

[0058]

[0059] The specific surface area, 0.08 mm fineness, setting time, and flexural and compressive strength of the prepared cement 1 and cement 2 were physically tested in accordance with GBT17671-2021 "Test method for strength of cement mortar (ISO)", GBT 1346-2011 "Test method for water consumption, setting time, and stability of cement standard consistency", GBT8074-2008 "Determination method of specific surface area of ​​cement - Blaine method", and GBT1345-2005 "Test method for cement fineness by sieve analysis".

[0060]

[0061] The cement prepared by using construction waste to replace sandstone tailings powder meets the requirements of GB 175-2007 "General Portland Cement" standard, realizes the resource utilization of construction waste, improves the urban living environment, and promotes the sustainable green development of the enterprise economy.

[0062] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. The embodiments of the present application have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Without departing from the scope and spirit of the described embodiments, many modifications and changes are obvious to those of ordinary skill in the art. The choice of terms used in this article is intended to best explain the principles of the embodiments, practical applications or improvements to the technology in the market, or to enable other ordinary technicians in the technical field to understand the embodiments disclosed herein.

Claims

1. An environmentally friendly cement clinker, characterized in that: Prepared by the following raw material ratio: Limestone 82-84 parts Iron tailings powder 2.8-4.2 parts 11.5-15.5 parts of construction waste The SiO2 content in the construction waste is 56-60%, and the Al2O3 content is 13-15%.

2. The environmentally friendly cement clinker according to claim 1, characterized in that: The construction waste contains 8.5-10.5% CaO and 1.8-2.2% R2O.

3. The environmentally friendly cement clinker according to claim 1, characterized in that: The MgO content in the construction waste is 1.8-2.2%.

4. The environmentally friendly cement clinker according to claim 1, characterized in that: The ratio of the construction waste to limestone is 1:(6-7).

5. The environmentally friendly cement clinker according to claim 1, characterized in that: The specific surface area of ​​the environmentally friendly cement clinker is 345-365m 2 / kg, the environmentally friendly cement clinker 0.08mm fineness is 2-2.4%.

6. The environmentally friendly cement clinker according to claim 1, characterized in that: The environmentally friendly cement clinker has a lime saturation ratio KH of 0.88-0.92, a silicon oxygen ratio N of 2.8-3.0, and an aluminum oxygen ratio P of 1.3-1.

5.

7. A method for preparing an environmentally friendly cement clinker according to any one of claims 1 to 6, characterized in that The following steps are involved: S1. Raw material grinding: According to the raw material ratio of environmentally friendly cement clinker, limestone, iron tailings powder and construction waste in the environmentally friendly cement clinker raw materials are added to the raw material roller press for mixing and grinding, and the feed rate is 110-130t / h; S2. Clinker calcination: add the ground material into the rotary kiln for calcination, feed rate 80-90t / h, coal powder amount at the kiln head 2.5-3.5t / h, coal powder amount at the kiln tail 5.5-6.5t / h, kiln tail temperature 1000-1100℃, to obtain environmentally friendly cement clinker.

8. The method for preparing environmentally friendly cement clinker according to claim 7, characterized in that: The coal powder has a fineness of ≤4.0% and a moisture content of ≤3.0%.

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