Cement raw material additive, preparation method thereof and preparation method of cement

Abstract

The invention relates to the technical field of cement, in particular to a cement raw material additive, a preparation method thereof and a preparation method of cement. The cement raw material additive provided by the invention comprises the following components in percentage by mass: 15%-25% of a biphenyl dispersant, 10%-15% of an oxidation protective agent, 5%-10% of a water-soluble mineralizer, 5%-10% of a stabilizer and the balance of water, the oxidation protective agent comprises 2, 4-dibromo dibenzoyl peroxide, and the chemical structural formula of the 2, 4-dibromo dibenzoyl peroxide is # imgabs0. According to the cement raw material additive disclosed by the invention, the yield increasing effect and the coal saving effect of the cement raw material additive can be ensured under the condition that alternative fuel is used for preparing cement clinker; and the phenomenon of'inactivation 'of the cement raw material additive when the alternative fuel is used is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of cement, in particular to a cement raw material additive and a preparation method thereof and a cement preparation method. Background Art

[0002] Cement is an indispensable building material and is widely used in construction projects such as houses, bridges, and roads. However, cement consumes a lot of energy and resources and emits a lot of CO2 during its production process. How to save energy and reduce carbon emissions and achieve sustainable development of cement production is an urgent problem that needs to be solved.

[0003] The cement production process includes three stages: raw material grinding, clinker calcination, and cement grinding, commonly known as "two grindings and one calcination". Adding admixtures in the cement production process has become one of the important means to improve production efficiency and reduce production costs. Raw material additives are admixtures added during the raw material grinding process. They can improve the grindability and calcinability of raw materials, improve the dispersion of raw materials, reduce the apparent activation energy of CaCO3 decomposition, increase the raw material output, and reduce the coal consumption required in the clinker calcination process, thereby achieving energy conservation and carbon reduction in cement production.

[0004] In recent years, alternative fuel technology has developed rapidly. By using high calorific value waste such as biomass fuel, industrial waste, waste tires, domestic garbage, sludge, etc. to replace natural fossil fuels, it is possible to achieve energy conservation and carbon reduction while improving the environmental benefits of cement companies. However, during the use of alternative fuels, it will also bring a series of problems such as high chloride ion content, affecting kiln conditions and clinker quality. Cement companies have found in production applications that the coal-saving effect of raw material additives has decreased after using alternative fuels, and even the raw material additives will be "deactivated". Therefore, many cement companies have stopped using raw material additives.

[0005] Most of the existing raw material additives are used when alternative fuels are not used. After alternative fuels are promoted and applied in cement bases, the coal-saving effect of raw material additives has deteriorated, causing many cement bases to stop using raw material additives. Alternative fuels such as plastic flakes are added from the decomposition furnace or kiln head cover by feeding, and decomposed into ethylene, propylene and other reducing products at high temperature, which preferentially react with the raw material additives adsorbed on the surface of the raw material, resulting in a reduction in the coal-saving effect of the raw material additives, or even failure.

[0006] In the application process of raw material additives, many cement bases reported that the product stability was poor, sometimes effective and sometimes ineffective. This is because many raw material additive manufacturers use a variety of raw material components and the quality is uncontrollable.

[0007] In view of this, this invention is proposed. Summary of the invention

[0008] The first object of the present invention is to provide a cement raw meal additive that can ensure the production improvement effect and coal saving effect of the cement raw meal additive when using alternative fuels to prepare cement clinker, and avoid the occurrence of "deactivation" of the cement raw meal additive when using alternative fuels.

[0009] The second object of the present invention is to provide a method for preparing a cement raw material additive, which has simple steps and is suitable for large-scale industrial production.

[0010] The third object of the present invention is to provide a method for preparing cement.

[0011] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0012] In a first aspect, the present invention provides a cement raw material additive, which comprises the following components in terms of mass percentage:

[0013] Biphenyl dispersant 15% to 25%, oxidation protection agent 10% to 15%, water-soluble mineralizer 5% to 10%, stabilizer 5% to 10%, and the balance is water;

[0014] The oxidation protection agent includes 2,4-dibromobenzoyl peroxide, and the chemical structural formula of the 2,4-dibromobenzoyl peroxide is:

[0015] Furthermore, the preparation method of 2,4-dibromobenzoyl peroxide comprises the following steps:

[0016] S1, reacting p-toluenesulfonyl bromide with antimony tribromide, followed by alkali washing and distillation to obtain 3-bromo-4-methylbenzenesulfonyl bromide;

[0017] S2, reacting the 3-bromo-4-methylbenzenesulfonyl bromide, azobisisobutyronitrile and bromine water to obtain α,α,α-2,4-pentabromotoluene;

[0018] S3, reacting the α,α,α-2,4-pentabromotoluene, ferric bromide and water, and obtaining 2,4-dibromobenzoyl bromide after distillation;

[0019] S4, reacting the 2,4-dibromobenzoyl bromide, sodium hydroxide, hydrogen peroxide, tetrabutylammonium bromide and water to obtain the 2,4-dibromobenzoyl peroxide;

[0020] Wherein, the chemical structural formula of the 3-bromo-4-methylbenzenesulfonyl bromide is: The chemical structural formula of α,α,α-2,4-pentabromotoluene is: The chemical structural formula of the 2,4-dibromobenzoyl bromide is:

[0021] Furthermore, the method for preparing 2,4-dibromobenzoyl peroxide comprises at least one of the following features (1) to (4);

[0022] (1) In step S1, the reaction comprises: reacting at 70 to 90° C. for 20 to 40 minutes;

[0023] (2) In step S2, the reaction comprises: reacting at 80-100° C. for 4-6 hours;

[0024] (3) In step S3, the reaction comprises: reacting at 60 to 80° C. for 1 to 3 hours;

[0025] (4) In step S4, the reaction comprises: reacting in an ice bath for 1 to 3 hours.

[0026] Further, it includes at least one of the following features (1) to (4);

[0027] (1) The biphenyl dispersant comprises biphenyl carboxylic acid compounds and / or biphenyl sulfonic acid compounds;

[0028] (2) The water-soluble mineralizer includes one or more of potassium fluoride, ammonium fluoride, sodium sulfate, potassium nitrate, ammonium chloride and potassium dihydrogen phosphate;

[0029] (3) The stabilizer includes sodium phenylphosphate compounds;

[0030] (4) The mass ratio of the water-soluble mineralizer to the biphenyl dispersant is 1:(2-4).

[0031] Further, the biphenyl dispersant includes one or more of 2'-methoxy-3'-nitrobiphenyl-3-carboxylic acid, 4'-methylbiphenyl-2-carboxylic acid, biphenyl-4-sulfonic acid and 4,4'-biphenyl disulfonic acid.

[0032] Furthermore, the stabilizer includes one or more of disodium 4-nitrophenyl phosphate, sodium 4-aminophenyl phosphate, sodium 4-hydroxyphenyl phosphate and sodium diphenyl phosphate.

[0033] In a second aspect, the present invention also provides a method for preparing the cement raw material additive as described above, comprising the following steps:

[0034] The components are mixed uniformly to obtain the cement raw material additive.

[0035] In a third aspect, the present invention further provides a method for preparing cement, comprising the following steps:

[0036] The cement raw material additive and the cement raw material are subjected to raw material grinding, calcination and clinker grinding in sequence to obtain the cement.

[0037] Furthermore, the calcination includes: using alternative fuel for calcination.

[0038] Furthermore, the mass of the cement raw material additive is 0.5‰ to 2‰ of the mass of the cement raw material.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The cement raw meal additive provided by the present invention can ensure the production improvement effect and coal saving and quality preservation effect of the cement raw meal additive when alternative fuels are used to prepare cement clinker; wherein, by adding an oxidizing protective agent, it can preferentially react with the reducing substances decomposed by the alternative fuel, thereby avoiding the failure of the cement raw meal additive; in addition, during the thermal decomposition of the raw meal, the oxidizing protective agent adsorbed on the surface of the raw meal can be thermally decomposed to provide oxygen, so that the fuel can be burned more fully and then promote the decomposition of the raw meal, thereby improving the coal saving effect; the use of a biphenyl dispersant can improve the raw meal production improvement and coal saving effects; on this basis, the addition of a water-soluble mineralizer is conducive to further reducing the energy consumption in the cement production process and is easy to be evenly dispersed in the raw meal; the stabilizer can stabilize the solution, thereby better exerting the coal saving and production improvement functions of the cement raw meal additive. DETAILED DESCRIPTION

[0041] The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If specific conditions are not indicated in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0042] The following is a detailed description of a cement raw material additive and a preparation method thereof and a cement preparation method of the present invention.

[0043] In some embodiments of the present invention, a cement raw material additive is provided, which comprises the following components in percentage by mass:

[0044] Biphenyl dispersant 15% to 25%, oxidation protection agent 10% to 15%, water-soluble mineralizer 5% to 10%, stabilizer 5% to 10%, and the balance is water;

[0045] The oxidation protective agent includes 2,4-dibromobenzoyl peroxide, and the chemical structure of 2,4-dibromobenzoyl peroxide is:

[0046] The cement raw meal additive of the present invention is a cement raw meal additive that saves coal and reduces consumption when using alternative fuels. Through the mutual coordination of various components, when using alternative fuels to prepare cement clinker, the cement raw meal additive can ensure the production improvement effect and coal saving effect, reduce the standard coal consumption by more than 3kgce / t.sh, and avoid the occurrence of the "inactivation" phenomenon of the cement raw meal additive when using alternative fuels; and in the application process of the cement raw meal additive, the cement raw meal additive has good stability.

[0047] Biphenyl dispersant: Biphenyl dispersant has two benzene rings connected to each other and an organic acid radical. The organic acid radical at one end of the biphenyl dispersant has a strong adsorption effect on raw material powder (limestone powder) and can be adsorbed on the surface of raw material powder. The biphenyl structure at the other end has a stronger repulsive effect due to steric hindrance, which can enhance the dispersibility of raw material powder and reduce the phenomenon of over-grinding, thereby improving the grindability and heat transfer efficiency of raw material. The effect of biphenyl dispersant on the burnability of raw material is reflected in the reduction of the apparent activation energy in CaCO3 raw material, which makes CaCO3 decompose more rapidly at a lower temperature. Before entering the kiln, biphenyl dispersant and CaCO3 generate organic acid calcium, which is easier to decompose than CaCO3. The addition of biphenyl dispersant to cement raw material additives can achieve the functions of increasing production and reducing consumption of cement production. Biphenyl dispersant plays an important role in increasing mill production and also plays a key role in calcination and coal saving. Moreover, the use of biphenyl dispersant and oxidative protective agent can play an excellent effect.

[0048] Oxidation protective agent: alternative fuels such as plastic flakes are added from the decomposition furnace or kiln head cover by feeding, and decomposed into ethylene, propylene and other reducing products at high temperature, which preferentially react with cement raw material additives adsorbed on the surface of raw materials, resulting in reduced coal saving effect of cement raw material additives, or even failure; the present invention adds an oxidation protective agent to compete with the ethylene and propylene reducing substances decomposed by the alternative fuels to preferentially react, thereby ensuring that the biphenyl dispersant can fully play its role, avoiding the failure of the biphenyl dispersant, and solving the problem of "deactivation" of cement raw material additives when alternative fuels are used; in addition, during the thermal decomposition of raw materials, the oxidation protective agent adsorbed on the surface of raw materials can be decomposed by heat to provide oxygen, so that the fuel burns more fully and then promotes the decomposition of raw materials, further improving the coal saving effect. The addition of the oxidation protective agent enables the cement raw material additives to play an excellent role, and the oxidation protective agent has a significant effect on calcination, which can improve the coal saving effect.

[0049] Water-soluble mineralizer: Soluble mineralizer can improve the burnability of raw meal, reduce the burning temperature, promote solid-phase reaction, accelerate the formation of clinker minerals, and further reduce the energy consumption in the cement production process. The addition of soluble mineralizer is conducive to improving the coal saving effect; at the same time, the mineralizer is water-soluble, and the cement raw meal additive is liquid, which is easy to calibrate and evenly dispersed in the raw meal, avoiding the problems of inaccurate measurement and uneven dispersion of powdered mineralizers.

[0050] Stabilizer: Stabilizer can improve the stability of cement raw meal additives and improve fluidity, so as to better play the coal-saving and production-increasing effects of cement raw meal additives; cement raw meal additives have many ingredients and their physical and chemical properties vary greatly. Adding a suitable stabilizer can stabilize the solution, which is beneficial to the pumping and metering of the raw meal additives and the performance of their effects; the addition of stabilizers is beneficial to improving the production increase of the mill and the coal-saving effects of calcination.

[0051] In some embodiments of the present invention, such as in different embodiments, the mass percentages of the components in the cement raw material additive may be as follows:

[0052] The mass percentage of the biphenyl dispersant may be 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25% or a range consisting of any two thereof;

[0053] The mass percentage of the oxidation protective agent can be 10%, 11%, 12%, 13%, 14%, 15% or a range consisting of any two thereof;

[0054] The mass percentage of the water-soluble mineralizer can be 5%, 6%, 7%, 8%, 9%, 10% or a range consisting of any two thereof;

[0055] The mass percentage of the stabilizer can be 5%, 6%, 7%, 8%, 9%, 10% or a range consisting of any two thereof.

[0056] If the content of biphenyl dispersant, oxidation protection agent, soluble mineralizer and stabilizer in cement raw meal additives is low, the cement raw meal additives cannot play an excellent role, and the mill production increase and coal saving and consumption reduction are reduced to a certain extent; the biphenyl dispersant has a certain foaming effect. If the content of biphenyl dispersant is too high, the produced cement raw meal additives will have more bubbles, affecting the product quality; if the content of oxidation protection agent is too high, the cost of cement raw meal additives will increase and the market competitiveness will be reduced; if the content of soluble mineralizer and stabilizer is too high, the amount of biphenyl dispersant and oxidation protection agent added will be reduced, and the effect of cement raw meal additives cannot be effectively exerted.

[0057] In some embodiments of the present invention, the preparation method of 2,4-dibromobenzoyl peroxide comprises the following steps:

[0058] S1. After reacting p-toluenesulfonyl bromide (CAS No.: 1950-69-2) and antimony tribromide (CAS No.: 7789-61-9), alkali washing and distillation are carried out in sequence to obtain 3-bromo-4-methylbenzenesulfonyl bromide;

[0059] S2, reacting 3-bromo-4-methylbenzenesulfonyl bromide, azobisisobutyronitrile (AIBN, CAS No.: 78-67-1) and bromine water (CAS No.: 7726-95-6) to obtain α,α,α-2,4-pentabromotoluene;

[0060] S3, reacting α,α,α-2,4-pentabromotoluene, ferric bromide (CAS No.: 10031-26-2) and water, and distilling to obtain 2,4-dibromobenzoyl bromide;

[0061] S4, reacting 2,4-dibromobenzoyl bromide, sodium hydroxide (CAS No.: 1310-73-2), hydrogen peroxide (CAS No.: 7722-84-1), tetrabutylammonium bromide (CAS No.: 1643-19-2) and water to obtain 2,4-dibromobenzoyl peroxide;

[0062] Among them, the chemical structural formula of 3-bromo-4-methylbenzenesulfonyl bromide is: The chemical structure of α,α,α-2,4-pentabromotoluene is: The chemical structure of 2,4-dibromobenzoyl bromide is:

[0063] The preparation method of 2,4-dibromobenzoyl peroxide, the synthesis route thereof is as follows:

[0064]

[0065] In some embodiments of the present invention, the preparation method of 2,4-dibromobenzoyl peroxide, in step S1, the reaction includes: reacting at 70-90°C for 20-40min; the molar ratio of p-toluenesulfonyl bromide to antimony tribromide is 1:(1.5-2); preferably, after the reaction, washing and separation are performed with sodium hydroxide solution, drying is performed with calcium bromide (CAS No.: 7789-41-5), distillation is performed, and fractions are collected.

[0066] In some embodiments of the present invention, in the method for preparing 2,4-dibromobenzoyl peroxide, in step S2, the reaction includes: reacting at 80-100°C for 4-6h; the molar ratio of 3-bromo-4-methylbenzenesulfonyl bromide, azobisisobutyronitrile and bromine water is 1:(0.09-0.11):(1.4-1.6).

[0067] In some embodiments of the present invention, in the method for preparing 2,4-dibromobenzoyl peroxide, in step S3, the reaction includes: reacting at 60-80° C. for 1-3 hours; the molar ratio of α,α,α-2,4-pentabromotoluene, ferric bromide and water is 1:(0.09-0.11):(0.4-0.6).

[0068] In some embodiments of the present invention, in the method for preparing 2,4-dibromobenzoyl peroxide, in step S4, the reaction includes: reacting for 1 to 3 hours under ice bath conditions; the molar ratio of 2,4-dibromobenzoyl bromide, sodium hydroxide, hydrogen peroxide, tetrabutylammonium bromide and water is 1: (0.9 to 1.1): (0.15 to 0.25): (0.0009 to 0.0011): (19 to 21).

[0069] In some embodiments of the present invention, the biphenyl dispersant includes biphenyl carboxylic acid compounds and / or biphenyl sulfonic acid compounds.

[0070] Compared with existing organic acid salts, the above-mentioned types of biphenyl dispersants have stronger functions of increasing raw material production and saving coal.

[0071] In some embodiments of the present invention, the water-soluble mineralizer includes one or more of potassium fluoride (CAS No.: 7789-23-3), ammonium fluoride (CAS No.: 12125-01-8), sodium sulfate (CAS No.: 7757-82-6), potassium nitrate (CAS No.: 7757-79-1), ammonium chloride (CAS No.: 12125-02-9) and potassium dihydrogen phosphate (CAS No.: 7778-77-0).

[0072] Adding a mineralizer can improve the burnability of raw materials during the calcination of raw materials, reduce the calcination temperature, promote solid phase reaction, accelerate the formation of clinker minerals, and thus reduce energy consumption in the cement production process. The mineralizers added in the cement production process are mostly powders, which have problems such as inaccurate metering and uneven dispersion. The present invention preferably uses a water-soluble mineralizer, which can be evenly dispersed in the raw materials, further increasing the effect of improving the burnability.

[0073] In some embodiments of the present invention, the stabilizer includes a sodium phenylphosphate compound.

[0074] Stabilizer is a surfactant with two opposite properties, lipophilicity and hydrophilicity, in the molecule. It can improve the stability of raw material additives and increase fluidity, thereby better exerting the coal saving and production increasing effects of cement raw material additives.

[0075] In some embodiments of the present invention, the mass ratio of the water-soluble mineralizer to the biphenyl dispersant is 1:(2-4); typically but not limiting, for example, the mass ratio of the water-soluble mineralizer to the biphenyl dispersant can be 1:2, 1:3, 1:4 or a range of any two thereof.

[0076] The ratio of water-soluble mineralizer to biphenyl dispersant plays an important role in the coal-saving effect of cement raw meal additives; adopting the above mass ratio range is conducive to improving the coal-saving effect of cement raw meal additives.

[0077] In some embodiments of the present invention, the biphenyl dispersant includes one or more of 2'-methoxy-3'-nitrobiphenyl-3-carboxylic acid (CAS No.: 376591-94-5), 4'-methylbiphenyl-2-carboxylic acid (CAS No.: 7148-03-0), biphenyl-4-sulfonic acid (CAS No.: 2113-68-0) and 4,4'-biphenyl disulfonic acid (CAS No.: 5314-37-4).

[0078] In some embodiments of the present invention, the stabilizer includes one or more of disodium 4-nitrophenyl phosphate (CAS No.: 4264-83-9), sodium 4-aminophenyl phosphate (CAS No.: 52331-30-3), sodium 4-hydroxyphenyl phosphate (CAS No.: 20368-79-0) and sodium diphenyl phosphate (CAS No.: 4376-01-6).

[0079] In some embodiments of the present invention, a method for preparing the above-mentioned cement raw material additive is also provided, comprising the following steps:

[0080] The components are mixed uniformly to obtain cement raw material additive.

[0081] The preparation method of the cement raw material additive of the present invention only requires mixing the components evenly, has simple steps and is suitable for large-scale production.

[0082] In some embodiments of the present invention, a method for preparing cement is also provided, comprising the following steps:

[0083] The cement raw material additive and cement raw material are subjected to raw material grinding, calcination and clinker grinding in sequence to obtain cement.

[0084] In some embodiments of the present invention, calcining includes: using an alternative fuel for calcining.

[0085] In some embodiments of the present invention, the mass of the cement raw material additive is 0.5‰ to 2‰ of the mass of the cement raw material; typically but not limiting, for example, the mass of the cement raw material additive is 0.5‰, 1‰, 1.5‰, 2‰ of the mass of the cement raw material or a range of any two thereof.

[0086] Example 1

[0087] The cement raw material additive provided in this embodiment includes the following components in terms of mass percentage:

[0088] Biphenyl dispersant 20%, oxidation protection agent 15%, water-soluble mineralizer 8%, stabilizer 8%, the balance is water;

[0089] Wherein, the biphenyl dispersant is: 2'-methoxy-3'-nitrobiphenyl-3-carboxylic acid;

[0090] The oxidation protective agents are: 2,4-dibromobenzoyl peroxide;

[0091] The water-soluble mineralizer is potassium fluoride, ammonium fluoride and sodium sulfate in a mass ratio of 1:0.8:1.

[0092] The stabilizer is: disodium 4-nitrophenyl phosphate and sodium 4-aminophenyl phosphate in a mass ratio of 1:1.

[0093] The chemical formula of 2,4-dibromobenzoyl peroxide is The specific preparation method comprises the following steps:

[0094] S1. Add 1000 g of p-toluenesulfonyl bromide to 15 g of antimony bromide and react at 80° C. for 30 min; then wash and separate with a 20 wt% sodium hydroxide solution, dry with calcium bromide (CAS No.: 7789-41-5) and distill, collect the fraction at 180° C. to obtain 3-bromo-4-methylbenzenesulfonyl bromide; the chemical structural formula of 3-bromo-4-methylbenzenesulfonyl bromide is

[0095] S2. After reacting the above 3-bromo-4-methylbenzenesulfonyl bromide, 10 g of azobisisobutyronitrile and 50 mL of bromine water at 90° C. for 5 h, distillation was performed and the fraction at 150° C. was collected to obtain α,α,α-2,4-pentabromotoluene; the chemical structure of α,α,α-2,4-pentabromotoluene is

[0096] S3, react the above α,α,α-2,4-pentabromotoluene, 10g ferric bromide and 50mL deionized water at 70°C for 2h, and then distill, collect the fraction at 150°C, and obtain 2,4-dibromobenzoyl bromide; the chemical structure of 2,4-dibromobenzoyl bromide is

[0097] S4. In an ice bath, stir the above 2,4-dibromobenzoyl bromide, 2500 mL of water, 300 g of sodium hydroxide, and 500 mL of hydrogen peroxide for 30 min, then add 1 g of tetrabutylammonium bromide and react for 2 h to obtain 2,4-dibromobenzoyl peroxide.

[0098] The preparation method of the cement raw material additive provided in this embodiment comprises the following steps:

[0099] The biphenyl dispersant, the oxidation protection agent, the water-soluble mineralizer, the stabilizer and water were weighed in sequence and added into a reaction kettle, and stirred and mixed at 25° C. for 1 hour to obtain a cement raw material additive.

[0100] Example 2

[0101] The cement raw material additive and preparation method thereof provided in this embodiment refer to Example 1, except that the biphenyl dispersant is: 4'-methylbiphenyl-2-carboxylic acid and biphenyl-4-sulfonic acid in a mass ratio of 1:0.8; the water-soluble mineralizer is: potassium nitrate and ammonium chloride in a mass ratio of 1:1; and the stabilizer is: sodium 4-aminophenylphosphate.

[0102] Example 3

[0103] The cement raw material additive and preparation method thereof provided in this embodiment refer to Example 1, except that the biphenyl dispersant is: 4'-methylbiphenyl-2-carboxylic acid and 4,4'-biphenyldisulfonic acid in a mass ratio of 1:0.8; the water-soluble mineralizer is: potassium fluoride and potassium dihydrogen phosphate in a mass ratio of 1:1; and the stabilizer is: disodium 4-nitrophenyl phosphate and sodium diphenyl phosphate in a mass ratio of 1:0.8.

[0104] Example 4

[0105] The cement raw material additive and its preparation method provided in this embodiment refer to Example 1, the only difference is that the cement raw material additive, calculated by mass percentage, includes the following components: 15% biphenyl dispersant, 10% oxidation protection agent, 5% water-soluble mineralizer, 5% stabilizer, and the balance is water.

[0106] Example 5

[0107] The cement raw material additive and preparation method thereof provided in this embodiment refer to Example 1, except that the cement raw material additive, calculated by mass percentage, includes the following components: 25% biphenyl dispersant, 15% oxidation protection agent, 10% water-soluble mineralizer, 10% stabilizer, and the balance is water.

[0108] Example 6

[0109] The cement raw material additive and preparation method thereof provided in this embodiment refer to Example 1, except that the mass percentage of the biphenyl dispersant is 15% and the mass percentage of the water-soluble mineralizer is 10%.

[0110] Example 7

[0111] The cement raw material additive and preparation method thereof provided in this embodiment refer to Example 1, except that the mass percentage of the biphenyl dispersant is 25% and the mass percentage of the water-soluble mineralizer is 5%.

[0112] Comparative Example 1

[0113] The cement raw material additive provided in this comparative example is the cement raw material energy-saving additive in the patent with publication number CN116768507A; it includes the following components in parts by mass: 10 parts of saponified waste alkali liquid, 3 parts of sodium carbonate, 10 parts of organic acid salt and 1 part of regulator; wherein the organic acid salt is sodium citrate and sodium formate in a mass ratio of 3:1; the regulator is sodium polystyrene sulfonate and carbonic acid in a mass ratio of 2:1.

[0114] Comparative Example 2

[0115] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the cement raw material additive and the preparation method thereof do not contain the biphenyl dispersant.

[0116] Comparative Example 3

[0117] The cement raw material additive and its preparation method provided in this comparative example refer to Example 1, except that it does not contain an oxidation protective agent.

[0118] Comparative Example 4

[0119] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the cement raw material additive and the preparation method thereof do not contain a soluble cement mineralizer.

[0120] Comparative Example 5

[0121] The cement raw material additive and its preparation method provided in this comparative example refer to Example 1, except that no stabilizer is contained.

[0122] Comparative Example 6

[0123] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the mass percentage of the biphenyl dispersant is 10%.

[0124] Comparative Example 7

[0125] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the mass percentage of the oxidation protection agent is 5%.

[0126] Comparative Example 8

[0127] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the mass percentage of the soluble mineralizer is 2%.

[0128] Comparative Example 9

[0129] The cement raw material additive and the preparation method thereof provided in this comparative example refer to Example 1, except that the mass percentage of the stabilizer is 2%.

[0130] Test example

[0131] Cement was prepared using the cement raw material additives of Examples 1 to 7 and Comparative Examples 1 to 9, respectively. A 5000t / d clinker production line was used to add the cement raw material additives to the cement raw material for raw material grinding, calcination and clinker grinding to obtain cement; wherein the amount of the cement raw material additive added was 1wt‰ of the raw material output per hour, the fuel consumption during the calcination process was 200t / d, and the daily production data was taken. The results are shown in Table 1.

[0132] The calculation method of the increase in the dry base output of raw mill R (t / h) is as follows: "raw mill output = raw mill cumulative output / actual cumulative operating time"; R = raw mill output after addition - raw mill output during the blank period.

[0133] The calculation method of the standard coal consumption reduction value S (kgce / t.sh) is as follows: "standard coal consumption = (raw coal consumption × calorific value weighted average) / 7000 / cumulative value of raw material scale entering the kiln / material consumption ratio + standard coal consumption converted from alternative fuels". S = standard coal consumption in the blank period - standard coal consumption after adding the agent.

[0134] Table 1

[0135]

[0136]

[0137]

[0138] As can be seen from Table 1 and Examples 1 to 5, the cement raw meal additive of the present invention can effectively increase mill output and reduce standard coal consumption for calcination when alternative fuels are used; the cement raw meal additive of the present invention still has good effects of increasing output and saving coal when alternative fuels are used.

[0139] Comparison between Example 6 and Example 7 and Example 1 shows that the ratio of water-soluble mineralizer to biphenyl dispersant in cement raw meal additive plays an important role in exerting the coal-saving effect of cement raw meal additive; when the ratio of water-soluble mineralizer to biphenyl dispersant is higher or lower, the coal-saving effect decreases.

[0140] By comparing Comparative Example 1 with Example 1, it can be seen that the existing raw meal additive in Comparative Example 1 has a certain production-increasing effect on the mill, and the standard coal consumption is reduced to a certain extent during the use of fossil fuels, which basically meets the production needs; when using alternative fuels, it has little effect on the output of the raw meal mill, but the coal-saving effect of the raw meal additive is significantly reduced, indicating that the use of alternative fuels has a greater impact on the coal-saving effect of the raw meal additive, and the reducing substances produced by thermal decomposition destroy the main components of the raw meal additive, affecting the coal-saving effect, resulting in the inability to meet the actual cement production needs.

[0141] Comparing Comparative Example 2 with Example 1, it can be seen that the cement raw material additive lacks biphenyl dispersant, and the effects of increasing unit output and reducing standard coal consumption are both reduced; the biphenyl dispersant plays an important role in increasing the unit output of the mill; at the same time, the coal-saving effect on calcination is significantly reduced. At this time, the coal-saving effect is mainly provided by the water-soluble mineralizer and the oxidizing protective agent, and the coal-saving effect is limited. The biphenyl dispersant and the oxidizing protective agent can be used together to achieve excellent results.

[0142] Comparing Comparative Example 3 with Example 1, it can be seen that the cement raw meal additive lacks an oxidation protective agent, the coal-saving effect is reduced, and the optimal effect and actual production requirements cannot be achieved; the oxidation protective agent has little effect on the mill, but has a greater impact on calcination, and the effect of reducing standard coal consumption is poor, which shows that the cement raw meal additive can only exert excellent effects when an oxidation protective agent is present.

[0143] Comparison between Comparative Example 4 and Example 1 shows that the cement raw material additive lacks soluble mineralizer components, which has little effect on the mill, but has a certain impact on coal saving, and the coal saving effect is reduced.

[0144] Comparison of Comparative Example 5 with Example 1 shows that the cement raw material additive lacks a stabilizer, and the mill production increase and clinker calcination coal saving are both reduced.

[0145] Comparison of Comparative Examples 6 to 9 with Example 1 shows that the contents of biphenyl dispersant, oxidation protection agent, soluble mineralizer and stabilizer in cement raw material additives are relatively low, and the mill production increase and coal saving and consumption reduction are reduced to a certain extent, and the excellent effect of cement raw material additives cannot be exerted.

[0146] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cement raw material additive, characterized in that: According to the mass percentage, it includes the following components: Biphenyl dispersant 15% to 25%, oxidation protection agent 10% to 15%, water-soluble mineralizer 5% to 10%, stabilizer 5% to 10%, and the balance is water; The oxidation protection agent includes 2,4-dibromobenzoyl peroxide, and the chemical structural formula of the 2,4-dibromobenzoyl peroxide is:

2. The cement raw material additive according to claim 1, characterized in that: The preparation method of 2,4-dibromobenzoyl peroxide comprises the following steps: S1, reacting p-toluenesulfonyl bromide with antimony tribromide, followed by alkali washing and distillation to obtain 3-bromo-4-methylbenzenesulfonyl bromide; S2, reacting the 3-bromo-4-methylbenzenesulfonyl bromide, azobisisobutyronitrile and bromine water to obtain α,α,α-2,4-pentabromotoluene; S3, reacting the α,α,α-2,4-pentabromotoluene, ferric bromide and water, and obtaining 2,4-dibromobenzoyl bromide after distillation; S4, reacting the 2,4-dibromobenzoyl bromide, sodium hydroxide, hydrogen peroxide, tetrabutylammonium bromide and water to obtain the 2,4-dibromobenzoyl peroxide; Wherein, the chemical structural formula of the 3-bromo-4-methylbenzenesulfonyl bromide is: The chemical structural formula of α,α,α-2,4-pentabromotoluene is: The chemical structural formula of the 2,4-dibromobenzoyl bromide is:

3. The cement raw material additive according to claim 2, characterized in that: The method comprises at least one of the following features (1) to (4); (1) In step S1, the reaction comprises: reacting at 70 to 90° C. for 20 to 40 minutes; (2) In step S2, the reaction comprises: reacting at 80-100° C. for 4-6 hours; (3) In step S3, the reaction comprises: reacting at 60 to 80° C. for 1 to 3 hours; (4) In step S4, the reaction comprises: reacting in an ice bath for 1 to 3 hours.

4. The cement raw material additive according to claim 2, characterized in that: The method comprises at least one of the following features (1) to (4); (1) The biphenyl dispersant comprises biphenyl carboxylic acid compounds and / or biphenyl sulfonic acid compounds; (2) The water-soluble mineralizer includes one or more of potassium fluoride, ammonium fluoride, sodium sulfate, potassium nitrate, ammonium chloride and potassium dihydrogen phosphate; (3) The stabilizer includes sodium phenylphosphate compounds; (4) The mass ratio of the water-soluble mineralizer to the biphenyl dispersant is 1:(2-4).

5. The cement raw material additive according to claim 4, characterized in that: The biphenyl dispersant includes one or more of 2'-methoxy-3'-nitrobiphenyl-3-carboxylic acid, 4'-methylbiphenyl-2-carboxylic acid, biphenyl-4-sulfonic acid and 4,4'-biphenyl disulfonic acid.

6. The cement raw material additive according to claim 4, characterized in that: The stabilizer includes one or more of disodium 4-nitrophenyl phosphate, sodium 4-aminophenyl phosphate, sodium 4-hydroxyphenyl phosphate and sodium diphenyl phosphate.

7. The method for preparing the cement raw material additive according to any one of claims 1 to 6, characterized in that: The steps include: The components are mixed uniformly to obtain the cement raw material additive.

8. A method for preparing cement, characterized in that: The steps include: The cement raw material additive and the cement raw material are subjected to raw material grinding, calcination and clinker grinding in sequence to obtain the cement.

9. The method for preparing cement according to claim 8, characterized in that: The calcination includes: using alternative fuel for calcination.

10. The method for preparing cement according to claim 8, characterized in that: The mass of the cement raw material additive is 0.5‰ to 2‰ of the mass of the cement raw material.

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