Anti-pulverization agent special for high-gelling-property titanium gypsum-based all-solid waste gelling material as well as preparation method and application of anti-pulverization agent

Abstract

The invention discloses a special anti-pulverization agent for a high-gelling-property titanium gypsum-based all-solid-waste cementing material and a preparation method and application of the special anti-pulverization agent, the special anti-pulverization agent is prepared from a superfine mineral admixture, industrial byproduct gypsum, an additive and a thickening agent, and the special anti-pulverization agent is doped into the titanium gypsum-based all-solid-waste cementing material to prepare the high-gelling-property titanium gypsum-based all-solid-waste cementing material. The prepared all-solid waste cementing material with high gelling property can be used as a substitute material of cement to be applied to concrete, filling, backfilling and roadbed. According to the invention, the titanium gypsum-based all-solid waste cementing material mainly comprising titanium gypsum is prepared, and the special anti-pulverization agent is supplemented to prepare the all-solid waste cementing material with high gelling property, so that the effects of greatly reducing the cost of the cementing material, reducing the emission of carbon dioxide and absorbing a large amount of titanium gypsum are achieved, and the method is a great innovation way for solid waste treatment.

Description

Technical Field

[0001] The present invention belongs to the field of solid waste resource utilization, and specifically relates to a special anti-pulverization agent for highly gelled titanium gypsum-based all-solid waste gelling material, and a preparation method and application thereof. Background Art

[0002] With rapid economic growth and continued urbanization, the demand for titanium dioxide is increasing to build better cities and roads, resulting in an increasing amount of titanium gypsum. With the rising cost of building materials and increasing environmental protection requirements in recent years, the resource utilization of discarded titanium gypsum has become a trend.

[0003] The use of titanium gypsum as an activator for slag to produce all-solid waste cementitious materials has become a hot research direction. However, compared with traditional cement, it uses sulfate in the solution to activate slag, and the reaction rate is slower. Therefore, it hardens slowly during use. This results in the surface slurry not being completely gelled and hardened during application, that is, the surface is powdered, which makes the long-term durability of titanium gypsum-based all-solid waste cementitious materials a problem when used.

[0004] Compared to traditional Portland cement, titanium gypsum-based all-solid waste cementitious materials utilize sulfate to depolymerize and repolymerize the vitreous material in slag. Consequently, their reaction rate is slower, leading to low early strength. This low strength directly results in the ineffective coagulation of the surface-reacted minerals, resulting in surface pulverization. This pulverization can damage the structure of titanium gypsum-based all-solid waste cementitious materials and lead to poor durability during long-term use.

[0005] Currently, titanium gypsum is primarily used for large-scale resource utilization in road paving. However, when used in this process, titanium gypsum is typically used in low concentrations. Higher concentrations can lead to sulfate leaching, resulting in performance issues with the roadbed. Therefore, the use of titanium gypsum in all-solid waste cementitious materials is the only way to achieve large-scale resource utilization of titanium gypsum in the future. Summary of the Invention

[0006] Purpose of the invention: The technical problem to be solved by the present invention is to address the deficiencies of the existing technology and provide a high-gelling titanium gypsum-based all-solid waste cementitious material special anti-powdering agent to eliminate the surface powdering problem of titanium gypsum when used in all-solid waste cementitious materials, and to expand the application of titanium gypsum in concrete, roadbed, filling and backfill.

[0007] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0008] A special anti-pulverization agent for highly gelled titanium gypsum-based all-solid waste cementitious materials, comprising the following components in percentage by mass:

[0009] Ultrafine mineral admixture, 60-80wt%;

[0010] Industrial by-product gypsum, 10-30wt%;

[0011] Admixture, 1-5wt%;

[0012] Thickener, 1-5wt%.

[0013] Specifically, the ultrafine mineral admixture is any one or more of fly ash, coal gangue, ultrafine calcium carbonate powder, and ultrafine stone powder; the specific surface area of ​​the ultrafine mineral admixture is not less than 500 cm 2 / g.

[0014] Coal gangue and ultrafine limestone powder are preferred.

[0015] Specifically, the industrial by-product gypsum is any one or more of phosphogypsum, desulfurized gypsum, and fluorinated gypsum, preferably phosphogypsum.

[0016] Specifically, the admixture is any one or more of polycarboxylate water reducer, citric acid water reducer, lignin sulfonate water reducer, and naphthalene water reducer, preferably polycarboxylate water reducer.

[0017] Specifically, the thickener is any one or both of cellulose ether and sodium dodecylbenzene sulfonate, preferably cellulose ether.

[0018] Furthermore, the preparation method of the special anti-pulverization agent for high-gelling titanium gypsum-based all-solid waste cementitious materials is specifically as follows: ultrafine mineral admixtures, industrial by-product gypsum, admixtures and thickeners in a mixer are uniformly mixed to obtain the anti-pulverization agent.

[0019] Furthermore, the present invention also claims protection for a highly gelled titanium gypsum-based all-solid waste gelling material comprising the following components in parts by mass:

[0020] Cement, 2-8wt%;

[0021] Mineral powder, 70-80wt%;

[0022] Titanium gypsum 18-25wt%;

[0023] The above components together constitute the all-solid waste cementitious material, and the total mass is 100%;

[0024] In addition, the special anti-powdering agent according to claim 1 is added in an amount of 1 / 10 to 1 / 2 of the total mass of the above solid waste cementitious materials.

[0025] Preferably, the cement is ordinary Portland cement; the mineral powder has a specific surface area of ​​380-450 m 2 / kg; the specific surface area of ​​the titanium gypsum dry powder is 300-400 m 2 / kg.

[0026] Furthermore, the present invention also claims a method for preparing the above-mentioned highly gelling titanium gypsum-based all-solid waste gelling material, comprising the following steps:

[0027] (1) Grind the slag in a ball mill for 30-120 min to prepare ore powder A;

[0028] (2) Drying the original titanium gypsum until there is no free water and grinding it in a ball mill for 5-60 minutes to prepare titanium gypsum dry powder B;

[0029] (3) Mixing mineral powder A, titanium gypsum dry powder B and cement in a mixer for 5-30 minutes to obtain all-solid waste cementitious material C;

[0030] (4) The special anti-powdering agent D described in claim 1 is mixed evenly with the all-solid waste cementitious material C.

[0031] Specifically, in step (4), the mixing is carried out using any one of vertical mill, ball mill and roller mill.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The titanium gypsum in the present invention does not need to be deironed and calcined to prepare anhydrous gypsum, which can make large-scale use of titanium gypsum and reduce the production cost of all-solid waste cementitious materials.

[0034] (2) The anti-pulverization agent prepared by the present invention can improve the strength level of all-solid waste cementitious materials. The strength performance of the high-performance titanium gypsum-based all-solid waste cementitious materials containing special anti-pulverization can be equal to the strength performance of ordinary Portland cement grades 425 to 625, effectively improving the anti-pulverization performance of the titanium gypsum-based all-solid waste cementitious materials and realizing the efficient application of titanium gypsum in all-solid waste cementitious materials.

[0035] (3) The present invention not only prepares a new type of titanium gypsum-based all-solid waste cementitious material, but also effectively improves the performance of the titanium gypsum-based all-solid waste cementitious material, and realizes the preparation of high-performance titanium gypsum-based all-solid waste cementitious material.

[0036] (4) The high-performance titanium gypsum-based all-solid waste cementitious material prepared by the present invention solves the problem that titanium gypsum can only be used on roadbeds, and realizes the application of large amounts of titanium gypsum in cement concrete, roadbeds, filling and backfilling.

[0037] (5) The present invention not only solves the problem of high-quality resource utilization of titanium gypsum, but also realizes the effective replacement of ordinary Portland cement in some application scenarios, helping the cement industry to achieve carbon neutrality and contributing to the healthy and sustainable development of titanium gypsum production enterprises and the cement building materials industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent.

[0039] Figure 1 The compressive strength of the titanium gypsum-based all-solid waste cementitious material at different hydration ages without and with the anti-pulverization agent in Example 1 is shown.

[0040] Figure 2 This is an SEM photograph of the hydration product of the highly gelling titanium gypsum-based all-solid waste cementitious material in Example 1 after 7 days.

[0041] Figure 3 These are photographs of the all-solid waste cementitious material samples without and with the anti-surface pulverization agent added in Example 1. DETAILED DESCRIPTION

[0042] The present invention can be better understood with reference to the following examples.

[0043] In the following examples, slag was sourced from Baowu Group Environmental Resources Technology Co., Ltd., undisturbed titanium gypsum was sourced from Zhenjiang Jiangsu Taibai Group Co., Ltd., and ordinary Portland cement, ultrafine mineral admixtures, admixtures, thickeners, etc. were all commercially available products.

[0044] Example 1

[0045] This embodiment provides a high-performance anti-pulverization agent for titanium gypsum-based all-solid waste cementitious materials and an application method thereof. The raw materials of the titanium gypsum-based all-solid waste cementitious materials are weighed according to the following mass percentages:

[0046] Ordinary Portland cement 5.0%;

[0047] Mineral powder 75.0%;

[0048] Original titanium gypsum (containing water) 20.0%;

[0049] Special anti-powdering agent is weighed according to the following mass percentage:

[0050] Fly ash 30%;

[0051] coal gangue 22%;

[0052] phosphogypsum 40%;

[0053] Polycarboxylate water reducer 3%;

[0054] Cellulose ether 5%;

[0055] The specific preparation method is as follows:

[0056] (1) Weigh 75% of the slag by mass and grind it in a ball mill for 60 minutes until the specific surface area of ​​the slag is 400 m 2 / kg;

[0057] (2) Weigh 20% of the original titanium gypsum, dry it at 110 °C until there is no free water, and grind it in a ball mill for 15 min to prepare titanium gypsum dry powder. The specific surface area of ​​the titanium gypsum dry powder is 350 m 2 / kg;

[0058] (3) Mixing the mineral powder obtained in steps (1) and (2) with titanium gypsum powder and 5% cement in a mixer for 10 minutes to obtain a new titanium gypsum-based all-solid waste cementitious material;

[0059] (4) Weigh 30% fly ash, 22% coal gangue, 40% phosphogypsum, 3% polycarboxylate water reducer and 5% cellulose ether and mix them in a mixer for 10 minutes to obtain a special anti-powdering agent;

[0060] (5) The anti-powdering agent D obtained in step (4) is packaged separately, and the whole solid waste cementitious material and the anti-powdering agent are mixed in a ratio of 2:1. The titanium gypsum-based whole solid waste cementitious material and the anti-powdering agent are mixed in a ball mill for 10 minutes;

[0061] (6) The compressive strength of the prepared high-cementitious titanium gypsum-based all-solid waste cementitious material was measured according to the "Test Method for Cement Mortar Strength (ISO)" (GB / T17671-2021). The compressive strength performance of the prepared high-cementitious titanium gypsum-based all-solid waste cementitious material at 3d, 7d, and 28d was 20MPa, 32MPa, and 45MPa, respectively. In addition, the compressive strength of the prepared all-solid waste cementitious material without the addition of the anti-pulverization agent in step (5) was measured together with the blank control group. The compressive strength performance of the prepared high-cementitious titanium gypsum-based all-solid waste cementitious material at 3d, 7d, and 28d was 15MPa, 26MPa, and 33MPa, respectively.

[0062] Example 2

[0063] This embodiment provides a special anti-pulverization agent for highly gelled titanium gypsum-based all-solid waste gelling material and its application method. The raw materials of the titanium gypsum-based all-solid waste gelling material are weighed according to the following mass percentages:

[0064] Ordinary Portland cement 8.0%;

[0065] Mineral powder 74.0%;

[0066] Original titanium gypsum (containing water) 18.0%;

[0067] Special anti-powdering agent is weighed according to the following mass percentage:

[0068] fly ash 48%;

[0069] Ultrafine stone powder 10%;

[0070] phosphogypsum 35%;

[0071] Polycarboxylate water reducer 1%;

[0072] Cellulose ether 6%;

[0073] The specific preparation method is as follows:

[0074] (1) Weigh 74% of the slag by mass and grind it in a ball mill for 90 minutes until the specific surface area of ​​the slag is 450 m 2 / kg;

[0075] (2) Weigh 18% of the original titanium gypsum, dry it at 100 °C until there is no free water, and grind it in a ball mill for 30 min to prepare titanium gypsum dry powder. The specific surface area of ​​the titanium gypsum dry powder is 300 m 2 / kg;

[0076] (3) Mixing the mineral powder obtained in steps (1) and (2) with titanium gypsum powder and 8% cement in a mixer for 10 minutes to obtain a new titanium gypsum-based all-solid waste cementitious material;

[0077] (4) Weigh 48% fly ash, 10% ultrafine stone powder, 35% phosphogypsum, 1% polycarboxylate water reducer and 6% cellulose ether and mix them in a mixer for 10 minutes to obtain an anti-powdering agent;

[0078] (5) The anti-powdering agent D obtained in step (4) is packaged separately, and the whole solid waste cementitious material and the anti-powdering agent are mixed in a ratio of 6:1. The titanium gypsum-based whole solid waste cementitious material and the anti-powdering agent are mixed in a ball mill for 10 minutes;

[0079] (6) The compressive strength of the prepared high-gelled titanium gypsum-based all-solid waste cementitious material was measured according to the "Test Method for Cement Mortar Strength (ISO) Method" (GB / T17671-2021). The compressive strength properties of the material at 3d, 7d and 28d were 23MPa, 34MPa and 48MPa, respectively.

[0080] Example 3

[0081] This embodiment provides a special anti-pulverization agent for highly gelled titanium gypsum-based all-solid waste gelling material and its application method. The raw materials of the titanium gypsum-based all-solid waste gelling material are weighed according to the following mass percentages:

[0082] Ordinary Portland cement 2.0%;

[0083] Mineral powder 77.0%;

[0084] Original titanium gypsum (containing water) 21.0%;

[0085] Special anti-powdering agent is weighed according to the following mass percentage:

[0086] Gangue 50%;

[0087] Ultrafine limestone powder 8%;

[0088] phosphogypsum 35%;

[0089] Polycarboxylate water reducer 1%;

[0090] Cellulose ether 6%;

[0091] The specific preparation method is as follows:

[0092] (1) Weigh 77% of the slag by mass and grind it in a ball mill for 70 minutes until the specific surface area of ​​the slag is 420 m 2 / kg;

[0093] (2) Weigh 21% of the original titanium gypsum, dry it at 90 °C until there is no free water, and grind it in a ball mill for 40 min to prepare titanium gypsum dry powder. The specific surface area of ​​the titanium gypsum dry powder is 320 m 2 / kg;

[0094] (3) Mixing the mineral powder obtained in steps (1) and (2) with titanium gypsum powder and 2% cement in a mixer for 15 minutes to obtain a new titanium gypsum-based all-solid waste cementitious material;

[0095] (4) Weigh 50% coal gangue, 8% ultrafine limestone powder, 35% phosphogypsum, 1% polycarboxylate water reducer and 6% cellulose ether and mix them in a mixer for 15 minutes to obtain an anti-powdering agent;

[0096] (5) The anti-powdering agent D obtained in step (4) is packaged separately, and the whole solid waste cementitious material and the anti-powdering agent are mixed in a ratio of 8:1. The titanium gypsum-based whole solid waste cementitious material and the anti-powdering agent are mixed in a ball mill for 5 minutes;

[0097] (6) The compressive strength of the prepared high-cementitious titanium gypsum-based all-solid waste cementitious material was measured according to the "Test Method for Cement Mortar Strength (ISO)" (GB / T17671-2021). The compressive strength properties of the prepared high-cementitious titanium gypsum-based all-solid waste cementitious material at 3d, 7d, and 28d were 25MPa, 38MPa, and 53MPa, respectively.

[0098] The compressive strength of the all-solid waste cementitious material without adding the anti-powdering agent and the high-gelling titanium gypsum-based all-solid waste cementitious material with adding the anti-powdering agent obtained in Example 1 at different hydration ages is as follows: Figure 1 As shown in the figure, it can be seen that the strength properties of the all-solid waste-based cementitious material have met the strength properties of ordinary Portland cement 425.

[0099] Figure 2 This is a SEM image of the hydration product of the highly gelling titanium gypsum-based all-solid waste cementitious material in Example 1 after 7 days of hydration. By the 7th day of hydration, the highly gelling titanium gypsum-based all-solid waste cementitious material had produced a large amount of ettringite and CSH gel. Its strength properties had rapidly developed, with compressive strength continuing to increase over the later stages. These results demonstrate that this method can effectively prepare a highly gelling all-solid waste cementitious material, and its strength properties far exceed the performance requirements of 425-grade ordinary Portland cement.

[0100] Figure 3 These are photos of the samples without anti-powdering agent and with anti-powdering agent added in Example 1 after 28 days of curing. It can be clearly seen from the photos that the surface of the sample without anti-powdering agent is powdery and rough, while the surface of the sample with anti-powdering agent is not powdery and is smooth.

[0101] The present invention provides a new resource utilization approach for titanium gypsum, solves the large-scale resource utilization approach for titanium gypsum, promotes the healthy and sustainable development of the titanium dioxide industry, and the resource-treated titanium gypsum can be effectively used as a raw material for all-solid waste cementitious materials, effectively reducing carbon and sulfur emissions in the cement industry.

[0102] The present invention provides a highly gelling titanium gypsum-based all-solid waste cementitious material special anti-pulverization agent, as well as its preparation method and application. While there are numerous methods and approaches for implementing this technical solution, the foregoing description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the present invention. Any components not specified in this embodiment may be implemented using existing technologies.

Claims

1. A special anti-powdering agent for high-gelling titanium gypsum-based all-solid waste cementitious materials, characterized in that: The following components are calculated in percentage by mass: Ultrafine mineral admixture, 60-80wt%; Industrial by-product gypsum, 10-30wt%; Admixture, 1-5wt%; Thickener, 1-5wt%.

2. The special anti-powdering agent for highly gelling titanium gypsum-based all-solid waste gelling material according to claim 1, characterized in that: The ultrafine mineral admixture is any one or more of fly ash, coal gangue, ultrafine calcium carbonate powder, and ultrafine stone powder; the specific surface area of ​​the ultrafine mineral admixture is not less than 500cm 2 / g.

3. The special anti-pulverization agent for highly gelling titanium gypsum-based all-solid waste gelling materials according to claim 1, characterized in that: The industrial by-product gypsum is any one or more of phosphogypsum, desulfurized gypsum and fluorinated gypsum.

4. The special anti-powdering agent for highly gelling titanium gypsum-based all-solid waste gelling material according to claim 1, characterized in that: The admixture is any one or more of polycarboxylic acid water reducer, citric acid water reducer, lignin sulfonate water reducer and naphthalene water reducer.

5. The special anti-pulverization agent for highly gelling titanium gypsum-based all-solid waste gelling material according to claim 1, characterized in that: The thickener is any one or two of cellulose ether and sodium dodecylbenzene sulfonate.

6. The method for preparing the special anti-powdering agent for high-gelling titanium gypsum-based all-solid waste gelling material according to claim 1, characterized in that: The superfine mineral admixture, industrial by-product gypsum, admixture and thickener in a mixer are mixed uniformly to obtain the product.

7. A highly gelling titanium gypsum-based all-solid waste gelling material, characterized in that: It includes the following components in parts by mass: Cement, 2-8wt%; Mineral powder, 70-80wt%; Titanium gypsum 18-25wt%; The above components together constitute the all-solid waste cementitious material, and the total mass is 100%; In addition, the special anti-powdering agent according to claim 1 is added in an amount of 1 / 10 to 1 / 2 of the total mass of the above solid waste cementitious materials.

8. The highly gelling titanium gypsum-based all-solid waste gelling material according to claim 7, characterized in that: The cement is ordinary Portland cement; the mineral powder has a specific surface area of ​​380-450 m 2 / kg; the specific surface area of ​​the titanium gypsum dry powder is 300-400 m 2 / kg.

9. The method for preparing a highly gelling titanium gypsum-based all-solid waste gelling material according to claim 7, characterized in that: The steps include: (1) Grind the slag in a ball mill for 30-120 min to prepare ore powder A; (2) Drying the original titanium gypsum until there is no free water and grinding it in a ball mill for 5-60 minutes to prepare titanium gypsum dry powder B; (3) Mixing mineral powder A, titanium gypsum dry powder B and cement in a mixer for 5-30 minutes to obtain all-solid waste cementitious material C; (4) The special anti-powdering agent D described in claim 1 is mixed evenly with the all-solid waste cementitious material C.

10. The method for preparing a highly gelling titanium gypsum-based all-solid waste gelling material according to claim 9, characterized in that: It is characterized in that In step (4), the mixing is carried out by any one of vertical mill, ball mill and roller mill.

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