Low-hydration-heat high-iron sulphoaluminate cementing material and preparation method thereof

Abstract

The invention relates to the technical field of cementitious material preparation, in particular to a low-hydration-heat high-iron sulphoaluminate cementitious material and a preparation method thereof.The cementitious material is prepared from, by mass, 10-15 parts of red mud, 45-55 parts of desulfurized gypsum, 12-18 parts of coal gangue, 20-26 parts of aluminum profile electroplating sludge and 10-25 parts of phase change materials. The preparation method comprises the following steps: S1, uniformly mixing the red mud, the desulfurized gypsum, the coal gangue and the aluminum profile electroplating sludge, putting the mixture into a high-temperature furnace, and calcining to obtain clinker; s2, continuously adding desulfurized gypsum into the clinker obtained in the step S1, and grinding to obtain a mixture; and S3, adding a phase change material into the mixture obtained in the step S2 to obtain the cementing material. The prepared cementing material can effectively absorb heat generated by hydration, and the prepared phase change material is effectively coated with epoxy resin, so that a better phase change effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of gelling material preparation, in particular to a low hydration heat high iron sulphoaluminate gelling material and a preparation method thereof. Background Art

[0003] High iron sulphoaluminate cement (FR-SAC) is a special cement with early strength, fast hardening and corrosion resistance. Compared with silicate cement, the carbon emissions during the production of FR-SAC are reduced by 35%. Therefore, high iron sulphoaluminate cement is a potential alternative material to silicate cement.

[0004] A lot of research has been done on the use of industrial solid waste to prepare FR-SAC. However, due to the large heat release of hydration of FR-SAC and the concentrated heat release time, when using solid waste-based FR-SAC to prepare concrete or other products, its excessive heat release and the accumulation of temperature inside the product cause the temperature to rise rapidly, which can easily cause cracking of the concrete or product, limiting its application scenarios and thus restricting the development of solid waste-based high-iron sulfoaluminate cement.

[0005] The present invention aims to solve the problem of excessive hydration heat during the use of solid waste-based sulfoaluminate cementitious materials, and provides a high-iron sulfoaluminate cementitious material with low hydration heat and a preparation method thereof. First, industrial solid waste is used to prepare high-iron sulfoaluminate cement with low hydration heat; then, solid waste-based high-iron sulfoaluminate cement is used as a cementitious material, and phase change materials are added thereto. The phase change materials in the phase change materials absorb the heat released by cement hydration, and the hydration heat of high-iron sulfoaluminate cement products is effectively reduced. In summary, the present invention aims to solve the deficiencies of the prior art, reduce the hydration heat of high-iron sulfoaluminate cement, reduce the corrosiveness of cement-based materials to phase change heat storage gelation, and obtain a low hydration heat cementitious material. Summary of the invention

[0006] The object of the present invention is to provide a low hydration heat high iron sulphoaluminate gelling material and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A low hydration heat high iron sulphoaluminate gelling material, comprising the following components by mass:

[0009] 10-15 parts of red mud, 45-55 parts of desulfurized gypsum, 12-18 parts of coal gangue, 20-26 parts of aluminum profile electroplating sludge and 10-25 parts of phase change material;

[0010] The preparation method of the phase change material comprises the following steps:

[0011] S101. Wash the expanded perlite and then dry it at 120 - 150 °C. Put the dried expanded perlite into a toluene solution containing polydimethylsilane and heat it under reflux at 100 - 110 °C for 10 - 15 h. Filter, and wash the product with sufficient toluene and then dry it under vacuum;

[0012] S102. Mix the expanded perlite treated in step S101 with paraffin wax, stir and mix at 55 - 75 °C for 2 - 4 h, ultrasonically treat the mixture at 55 - 75 °C for 30 min, and finally filter it through filter paper;

[0013] S103. Disperse the expanded perlite treated in step S102 into a toluene solution containing an amphiphilic polymer, react at 30 - 40 °C for 6 - 12 h, then filter, and dry the filtered product under vacuum;

[0014] S104. Disperse the expanded perlite treated in step S103 into a toluene solution containing epoxy resin, continue to add a curing agent and a catalyst to the toluene solution, heat to 40 °C, continuously stir and react for 4 - 10 h, then filter and separate the product, and continue to dry the product at 55 °C for 1 - 3 h to obtain the phase change material.

[0015] Further, the particle size of the expanded perlite in step S101 is 1 - 2.5 mm; the mass ratio of the expanded perlite, polydimethylsilane and toluene in step S101 is (5 - 10):1:(20 - 30).

[0016] Further, the mass ratio of the paraffin wax used in step S102 to the expanded perlite treated in step S101 is 1:(2 - 4).

[0017] Further, the amphiphilic polymer used in step S103 is a polystyrene - polyethylene glycol amphiphilic polymer.

[0018] Further, the mass ratio of the expanded perlite treated in step S102 to the amphiphilic polymer and toluene in step S103 is (2 - 4):1:(15 - 20).

[0019] Further, the curing agent in step S104 is diethylenetriamine, the catalyst is 2,4,6 - tris(dimethylaminomethyl)phenol, and the epoxy resin is bisphenol A epoxy resin.

[0020] Further, the mass ratio of the catalyst, curing agent, epoxy resin and acetone to the expanded perlite treated in step S103 in step S104 is 1:3:(4 - 6):(50 - 60):(10 - 20).

[0021] A preparation method of a high-iron sulphoaluminate cementitious material with low heat of hydration, comprising the following steps:

[0022] S1. Mix red mud, desulphurized gypsum, coal gangue and aluminum profile electroplating sludge evenly and then put them into a high-temperature furnace for calcination. The calcination temperature is 1250 - 1350 °C, and the heat preservation time is 30 - 60 min to obtain clinker;

[0023] S2. Continue to add desulphurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200-mesh sieve to obtain a mixture;

[0024] S3. Add a phase change material to the mixture obtained in step S2, and stir and mix evenly to obtain a high-iron sulphoaluminate cementitious material with low heat of hydration.

[0025] Further, the mass ratio of the desulphurized gypsum added in step S2 to the desulphurized gypsum added in step S1 is 1:4.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. In the present invention, by introducing a phase change material, the heat of hydration of the high-iron sulphoaluminate cement product is effectively absorbed, the curing product is prevented from cracking, and the strength of the curing product is improved;

[0028] 2. In the present invention, when preparing the phase change material, the expanded perlite is first modified hydrophobically to improve its compatibility with paraffin wax, so that the paraffin wax can better enter the pores of the expanded perlite. Through the bridging action of the amphiphilic polymer, epoxy resin is introduced outside the hydrophobic expanded perlite to protect the phase change paraffin;

[0029] 3. The hydrophobic end of the amphiphilic polymer in the present invention binds to the expanded perlite, and the hydrophilic end of polyethylene glycol binds to the epoxy resin. It can not only direct the epoxy resin to coat the expanded perlite, but also polyethylene glycol can further crosslink with the epoxy resin to improve the strength. Description of the Drawings

[0030] Figure 1 is the process flow chart for preparing the cementitious material in the present invention;

[0031] Figure 2 is the process flow chart for preparing the phase change material in the present invention;

[0032] Figure 3 is the XRD pattern of the clinker prepared in Example 1 of the present invention;

[0033] Figure 4 is the SEM image of the clinker prepared in Example 1 of the present invention;

[0034] Figure 5It is the heat of hydration diagram of the clinker prepared in Example 1 of the present invention;

[0035] Figure 6 It is the heat of hydration diagram of the low heat of hydration cementitious material prepared in Example 1 of the present invention. Detailed implementation manners

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0037] Please refer to Figures 1 to 6 , the present invention provides:

[0038] Example 1

[0039] A preparation method of a low heat of hydration high-iron sulphoaluminate cementitious material, comprising the following steps:

[0040] S1. Mix 60 g of red mud, 200 g of desulphurized gypsum, 80 g of coal gangue and 120 g of aluminum profile electroplating sludge evenly, and then put them into a high-temperature furnace for calcination. The calcination temperature is 1300 °C and the heat preservation time is 45 min to obtain clinker;

[0041] S2. Continuously add 50 g of desulphurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200-mesh sieve to obtain a mixture;

[0042] S3. Add 90 g of phase change material to the mixture obtained in step S2, and stir and mix evenly to obtain a low heat of hydration high-iron sulphoaluminate cementitious material;

[0043] The preparation method of the above phase change material comprises the following steps:

[0044] S101. Wash 180 g of expanded perlite with a particle size of 2 mm and dry it at 130 °C. Put the dried expanded perlite into a toluene solution containing polydimethylsilane and heat it under reflux at 105 °C for 12 h. The amounts of polydimethylsilane and toluene are 30 g and 750 g respectively. Filter, and wash the product with sufficient toluene and then dry it under vacuum;

[0045] S102. Mix 160 g of expanded perlite treated in step S101 with 55 g of paraffin wax, stir and mix at 65 °C for 3 h, ultrasonically treat the mixture at 65 °C for 30 min, the ultrasonic frequency is 30 KHz, and finally filter through filter paper;

[0046] S103. Disperse 160 g of expanded perlite processed in step S102 into a toluene solution containing a polystyrene - polyethylene glycol amphiphilic polymer. The amounts of the polystyrene - polyethylene glycol amphiphilic polymer and toluene are 60 g and 1080 g respectively. React at 36 °C for 10 h, then filter, and vacuum - dry the filtered product;

[0047] S104. Disperse 150 g of expanded perlite processed in step S103 into a toluene solution containing bisphenol A epoxy resin. Continuously add diethylenetriamine and 2,4,6 - tris(dimethylaminomethyl)phenol to the toluene solution. The amounts of diethylenetriamine, 2,4,6 - tris(dimethylaminomethyl)phenol, bisphenol A epoxy resin, and toluene are 30 g, 10 g, 50 g, and 550 g respectively. Heat to 40 °C, continuously stir and react for 5 h, then filter and separate the product. The product is further dried at 55 °C for 2 h to obtain the phase - change material.

[0048] Example 2

[0049] A preparation method of a low - heat - of - hydration high - iron sulphoaluminate cementitious material, comprising the following steps:

[0050] S1. Mix 70 g of red mud, 252 g of desulphurized gypsum, 84 g of coal gangue, and 140 g of aluminum profile electroplating sludge evenly, and then put them into a high - temperature furnace for calcination. The calcination temperature is 1250 °C and the heat - preservation time is 30 min to obtain the clinker;

[0051] S2. Continuously add 63 g of desulphurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200 - mesh sieve to obtain the mixture;

[0052] S3. Add 175 g of phase - change material to the mixture obtained in step S2, stir and mix evenly to obtain the low - heat - of - hydration high - iron sulphoaluminate cementitious material;

[0053] The preparation method of the above - mentioned phase - change material comprises the following steps:

[0054] S101. Wash 252 g of expanded perlite with a particle size of 1 mm, then dry it at 120 °C. Put the dried expanded perlite into a toluene solution containing polydimethylsilane and heat - reflux at 100 °C for 10 h. The amounts of polydimethylsilane and toluene are 50.4 g and 1008 g respectively. Filter, and wash the product with sufficient toluene and then vacuum - dry;

[0055] S102. Mix 224 g of expanded perlite processed in step S101 with 112 g of paraffin wax, stir and mix at 55 °C for 2 h, ultrasonically treat the mixture at 55 °C for 30 min with an ultrasonic frequency of 30 KHz, and finally filter through filter paper;

[0056] S103. Disperse 224 g of expanded perlite processed in step S102 into a toluene solution containing a polystyrene - polyethylene glycol amphiphilic polymer. The amounts of the polystyrene - polyethylene glycol amphiphilic polymer and toluene are 112 g and 1680 g respectively. React at 30 °C for 6 h, then filter, and vacuum - dry the filtered product.

[0057] S104. Disperse 210 g of expanded perlite processed in step S103 into a toluene solution containing bisphenol A epoxy resin. Continuously add diethylenetriamine and 2,4,6 - tris(dimethylaminomethyl)phenol to the toluene solution. The amounts of diethylenetriamine, 2,4,6 - tris(dimethylaminomethyl)phenol, bisphenol A epoxy resin, and toluene are 63 g, 21 g, 84 g, and 1050 g respectively. Heat to 40 °C, continuously stir and react for 4 h, then filter and separate the product. The product is further dried at 55 °C for 1 h to obtain the phase - change material.

[0058] Example 3

[0059] A preparation method of a low - heat - of - hydration high - iron sulphoaluminate cementitious material, comprising the following steps:

[0060] S1. Mix 75 g of red mud, 220 g of desulphurized gypsum, 90 g of coal gangue, and 130 g of aluminum profile electroplating sludge evenly, and then put them into a high - temperature furnace for calcination. The calcination temperature is 1350 °C and the heat - preservation time is 60 min to obtain the clinker.

[0061] S2. Continuously add 55 g of desulphurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200 - mesh sieve to obtain the mixture.

[0062] S3. Add 125 g of phase - change material to the mixture obtained in step S2, and stir and mix evenly to obtain the low - heat - of - hydration high - iron sulphoaluminate cementitious material.

[0063] The preparation method of the above - mentioned phase - change material comprises the following steps:

[0064] S101. Wash 180 g of expanded perlite with a particle size of 2.5 m and then dry it at 150 °C. Put the dried expanded perlite into a toluene solution containing polydimethylsilane and heat - reflux at 110 °C for 15 h, then filter. The amounts of polydimethylsilane and toluene are 18 g and 540 g respectively. Wash the product with sufficient toluene and then vacuum - dry it.

[0065] S102. Mix 160 g of expanded perlite processed in step S101 with 40 g of paraffin, stir and mix at 75 °C for 4 h, ultrasonically treat the mixture at 75 °C for 30 min with an ultrasonic frequency of 30 KHz, and finally filter through filter paper.

[0066] S103. Disperse 160 g of expanded perlite processed in step S102 into a toluene solution containing a polystyrene - polyethylene glycol amphiphilic polymer. The amounts of the polystyrene - polyethylene glycol amphiphilic polymer and toluene are 40 g and 800 g respectively. React at 40 °C for 12 h, then filter, and vacuum - dry the filtered product.

[0067] S104. Disperse 150 g of expanded perlite processed in step S103 into a toluene solution containing bisphenol A epoxy resin. Continuously add a curing agent and a catalyst to the toluene solution. The amounts of diethylenetriamine, 2,4,6 - tris(dimethylaminomethyl)phenol, bisphenol A epoxy resin, and toluene are 22.5 g, 7.5 g, 45 g, and 450 g respectively. Heat to 40 °C, continuously stir and react for 10 h, then filter and separate the product. The product is further dried at 55 °C for 3 h to obtain the phase - change material.

[0068] Example 4

[0069] A preparation method of a low - heat - of - hydration high - iron sulphoaluminate cementitious material, comprising the following steps:

[0070] S1. Mix 84 g of red mud, 240 g of desulfurized gypsum, 96 g of coal gangue, and 144 g of aluminum profile electroplating sludge evenly, then put them into a high - temperature furnace for calcination. The calcination temperature is 1300 °C and the heat - preservation time is 45 min to obtain the clinker.

[0071] S2. Continuously add 60 g of desulfurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200 - mesh sieve to obtain the mixture.

[0072] S3. Add 132 g of phase - change material to the mixture obtained in step S2, stir and mix evenly to obtain the low - heat - of - hydration high - iron sulphoaluminate cementitious material.

[0073] The preparation method of the above - mentioned phase - change material comprises the following steps:

[0074] S101. Wash 216 g of expanded perlite with a particle size of 2 mm, then dry it at 140 °C. Put the dried expanded perlite into a toluene solution containing polydimethylsilane and heat - reflux at 105 °C for 11 h. The amounts of polydimethylsilane and toluene are 27 g and 612 g respectively. Filter, and wash the product with sufficient toluene and then vacuum - dry.

[0075] S102. Mix 192 g of expanded perlite processed in step S101 with 72 g of paraffin wax, stir and mix at 60 °C for 3 h, ultrasonically treat the mixture at 60 °C for 30 min with an ultrasonic frequency of 30 KHz, and finally filter through filter paper.

[0076] S103. Disperse 192 g of expanded perlite processed in step S102 into a toluene solution containing a polystyrene - polyethylene glycol amphiphilic polymer. The amounts of the polystyrene - polyethylene glycol amphiphilic polymer and toluene are 60 g and 1020 g respectively. React at 35 °C for 10 h, then filter, and vacuum - dry the filtered product.

[0077] S104. Disperse 180 g of expanded perlite processed in step S103 into a toluene solution containing bisphenol A epoxy resin. Continue to add diethylenetriamine and 2,4,6 - tris(dimethylaminomethyl)phenol to the toluene solution. The amounts of diethylenetriamine, 2,4,6 - tris(dimethylaminomethyl)phenol, bisphenol A epoxy resin, and toluene are 36 g, 12 g, 66 g, and 690 g respectively. Heat to 40 °C, continuously stir and react for 5 h, then filter and separate the product. The product is further dried at 55 °C for 1.5 h to obtain the phase - change material.

[0078] Comparative Example 1

[0079] The difference between Comparative Example 1 and Example 1 is that step S103 is completely cancelled, and the remaining steps are exactly the same as those in Example 1.

[0080] Comparative Example 2

[0081] The difference between Comparative Example 2 and Example 1 is that step S104 is completely cancelled, and the remaining steps are exactly the same as those in Example 1.

[0082] Comparative Example 3

[0083] The difference between Comparative Example 3 and Example 1 is that steps S101, S103, and step S104 are cancelled, and the remaining steps are exactly the same as those in Example 1.

[0084] Comparative Example 4

[0085] The difference between Comparative Example 4 and Example 1 is that the addition of the phase - change material is completely cancelled, and the remaining steps are exactly the same as those in Example 1.

[0086] A total of 8 groups of cementitious materials are prepared through the above - mentioned Examples 1 - 4 and Comparative Examples 1 - 4. Mix the cementitious materials, water, and standard sand evenly according to a mass ratio of 2:1:5. After vibrating with a mold, specimens are obtained. Specifically, each group of specimens uses 500 g of cementitious materials, 250 g of water, and 1250 g of standard sand. Cure the specimens in an environment with a temperature of 20 °C and a relative humidity of 90% for 28 d, and measure the compressive strength and flexural strength at 7 d and 28 d of curing. The test standard adopts GB / T 17671 - 2021 "Test Method for Strength of Cement Mortar". The test results are shown in Table 1 below:

[0087] Table 1: Strength Test Table of Specimens Prepared in Examples 1 - 4 and Comparative Examples 1 - 4

[0088]

[0089]

[0090] From the data of Example 1 and Comparative Example 1 above, it can be seen that after the treatment of step S103, an amphiphilic polymer can be introduced, enhancing the coating effect of epoxy resin on the outer side of expanded perlite. The epoxy resin itself can further combine with the polyethylene glycol segment to improve the strength. From the measurement results, the flexural and compressive strengths of the specimens are both enhanced; from the data of Example 1 and Comparative Example 2, it can be seen that in the present invention, epoxy resin is introduced to coat the outer side of expanded perlite to prevent paraffin from flowing out of the pores of expanded perlite, and the role of the phase change material is better exerted; Comparative Example 3 is a common method of directly introducing phase change paraffin into expanded perlite, and its effect on curing is less than that of the cementitious material prepared by the present invention.

[0091] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low heat of hydration high-iron sulphoaluminate cementitious material, characterized in that, It comprises the following components by mass parts: 10 - 15 parts of red mud, 45 - 55 parts of desulfurized gypsum, 12 - 18 parts of coal gangue, 20 - 26 parts of aluminum profile electroplating sludge, and 10 - 25 parts of phase change material; The preparation method of the phase change material comprises the following steps: S101. After cleaning expanded perlite, it is dried at 120 - 150 °C. The dried expanded perlite is put into a toluene solution containing polydimethylsilane and heated under reflux at 100 - 110 °C for 10 - 15 h, filtered, and the product is washed with sufficient toluene and then dried in vacuum; S102. The expanded perlite treated in step S101 is mixed with paraffin wax, stirred and mixed at 55 - 75 °C for 2 - 4 h, the mixture is ultrasonically treated at 55 - 75 °C for 30 min, and finally filtered through filter paper; S103. The expanded perlite treated in step S102 is dispersed into a toluene solution containing amphiphilic polymer, reacted at 30 - 40 °C for 6 - 12 h, then filtered, and the filtered product is dried in vacuum; S104. The expanded perlite treated in step S103 is dispersed into a toluene solution containing epoxy resin. A curing agent and a catalyst are continuously added to the toluene solution, heated to 40 °C, continuously stirred and reacted for 4 - 10 h, then the product is filtered and separated, and the product is further dried at 55 °C for 1 - 3 h to obtain the phase change material.

2. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 1, wherein In step S101, the particle size of the expanded perlite is 1 - 2.5 mm; the mass ratio of the expanded perlite, polydimethylsilane and toluene in step S101 is (5 - 10):1:(20 - 30).

3. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 1, characterized in that, In step S102, the mass ratio of the paraffin wax used to the expanded perlite treated in step S101 is 1:(2 - 4).

4. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 1, wherein, The amphiphilic polymer used in step S103 is polystyrene - polyethylene glycol amphiphilic polymer.

5. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 4, wherein The mass ratio of the expanded perlite treated in step S102 to the amphiphilic polymer and toluene in step S103 is (2 - 4):1:(15 - 20).

6. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 1, wherein The curing agent in step S104 is diethylenetriamine, the catalyst is 2,4,6 - tris(dimethylaminomethyl)phenol, and the epoxy resin is bisphenol A epoxy resin.

7. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 6, characterized in that, In step S104, the mass ratio of the catalyst, curing agent, epoxy resin, acetone to the expanded perlite treated in step S103 is 1:3:(4 - 6):(50 - 60):(10 - 20).

8. A preparation method of a low heat of hydration high-iron sulphoaluminate cementitious material according to any one of claims 1-7, characterized in that, It comprises the following steps: S1. Mix red mud, desulfurized gypsum, coal gangue and aluminum profile electroplating sludge evenly and then put them into a high - temperature furnace for calcination. The calcination temperature is 1250 - 1350 °C, and the heat preservation time is 30 - 60 min to obtain clinker; S2. Continue to add desulfurized gypsum to the clinker obtained in step S1, mix evenly, then put it into a grinder for grinding, and pass through a 200 - mesh sieve to obtain a mixture; S3. Add the phase change material to the mixture obtained in step S2, stir and mix evenly to obtain a low - heat - of - hydration high - iron sulfoaluminate cementitious material.

9. The low heat of hydration high-iron sulphoaluminate cementitious material according to claim 8, characterized in that, In step S2, the mass ratio of the desulfurized gypsum added to the desulfurized gypsum added in step S1 is 1:4.

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