Papermaking white mud-containing prefabricated internal partition wall board and preparation method thereof

Abstract

The invention relates to the field of building materials, and particularly discloses a prefabricated internal partition wall board containing papermaking white mud and a preparation method of the prefabricated internal partition wall board. A prefabricated internal partition wall board containing papermaking white mud is formed by pouring lightweight concrete containing papermaking white mud, and the lightweight concrete containing papermaking white mud comprises the following raw materials in parts by weight: 20-30 parts of activated papermaking white mud, 20-30 parts of cement, 10-20 parts of fly ash, 1-3 parts of a water reducing agent, 5-8 parts of fibers and 3-5 parts of sodium carboxymethyl cellulose. Through the synergistic effect of all the components, a uniform three-dimensional network is formed in the concrete, generation and expansion of microcracks are inhibited, and the density and cracking resistance of the lightweight concrete are improved.

Description

Technical Field

[0001] This application relates to the field of building materials, and in particular to a prefabricated interior partition wall panel containing papermaking bleach and its preparation method. Background Technology

[0002] In the construction field, interior partition walls, as an important building material for dividing interior spaces, have continuously improved with the development of construction technology. With increasing demands for building quality and environmental protection, the performance and environmental friendliness of interior partition walls have received growing attention. Replacing some cement with industrial solid waste from papermaking sludge, optimizing the microstructure of concrete, and reducing drying shrinkage to inhibit wall panel cracking can not only solve the environmental pollution problems caused by papermaking sludge but also find a new way to reuse papermaking sludge resources, achieving resource recycling. This has become an important research direction in the construction field.

[0003] The existing technology for using papermaking sludge as a raw material for interior partition boards mainly adopts the method of directly and simply mixing papermaking sludge. However, the surface of papermaking sludge contains substances such as a silicon-aluminum layer, and the papermaking sludge has low activity and weak bonding ability with cement hydrates. If the dosage is too high, it will seriously deteriorate the strength and durability of the board, and the board is prone to cracking. Therefore, the dosage of sludge in traditional methods is limited, and it is impossible to consume this solid waste on a large scale. Summary of the Invention

[0004] In order to improve the application of existing papermaking sludge in interior partition boards, this application provides a prefabricated interior partition board containing papermaking sludge and its preparation method.

[0005] In a first aspect, this application provides a prefabricated interior partition wall panel containing papermaking sludge, which adopts the following technical solution: a prefabricated interior partition wall panel containing papermaking sludge, wherein the prefabricated interior partition wall panel is formed by pouring lightweight concrete containing papermaking sludge, and the lightweight concrete containing papermaking sludge comprises the following raw materials in parts by weight: 20-30 parts activated papermaking sludge, 20-30 parts cement, 10-20 parts fly ash, 1-3 parts water-reducing agent, 5-8 parts fiber, and 3-5 parts sodium carboxymethyl cellulose.

[0006] By adopting the above technical solutions, the activated white mud can undergo a pozzolanic reaction with calcium hydroxide, a cement hydration product, to generate additional CSH gel, improving later-stage strength, density, and durability. Simultaneously, the activated papermaking white mud can largely replace cement, reducing costs and conserving solid waste resources. Sodium carboxymethyl cellulose can form a water film on the surface of the papermaking white mud particles, preventing the white mud from absorbing or evaporating water too quickly, ensuring the continuous pozzolanic reaction between the white mud and cement, and reducing plastic shrinkage and drying shrinkage caused by water absorption and evaporation. Adding fibers can bear and disperse stress when shrinkage stress occurs between the papermaking white mud and the cement matrix, inhibiting the generation and propagation of microcracks. Fibers can form a uniform three-dimensional network in concrete, firmly mechanically bonding with the papermaking white mud and cement matrix, improving the density and crack resistance of lightweight concrete.

[0007] Preferably, the activated papermaking sludge raw material includes sodium hexametaphosphate, aluminate and papermaking sludge, and the mass ratio of sodium hexametaphosphate, aluminate and papermaking sludge is (0.5-2):(1-3):10.

[0008] By adopting the above technical solution, sodium hexametaphosphate can be firmly adsorbed onto the surface of papermaking bleach particles through adsorption and chemical bonding. Electrostatic repulsion prevents the agglomeration of the bleach particles, promoting their stable dispersion in the concrete system. Aluminate esters can enhance the bonding force and interfacial compatibility between papermaking bleach and the cement matrix, improve the overall strength of the concrete, and reduce the incompatibility issues between papermaking bleach and the cement matrix.

[0009] Preferably, the method for preparing the activated papermaking sludge includes the following specific steps: pulverizing the papermaking sludge and heating it, then adding sodium hexametaphosphate and aluminate ester in sequence for wet grinding to obtain the activated papermaking sludge.

[0010] By adopting the above technical solution, the addition of sodium hexametaphosphate can first deagglomerate the large agglomerates of papermaking sludge into fine, dispersed individual particles, thereby increasing the specific surface area of ​​the papermaking sludge. Then, the aluminate enhances the bonding force between the papermaking sludge and the cement matrix, thereby improving the overall strength and crack resistance of the concrete.

[0011] Preferably, the heating temperature is 110-120℃.

[0012] Preferably, the activated papermaking sludge is pre-modified with sodium carboxymethyl cellulose. The modification method includes the following specific steps: dissolving sodium carboxymethyl cellulose by heating in a water bath, adding the activated papermaking sludge, adding an accelerator, mixing and maintaining the temperature for reaction, and then centrifuging and drying to obtain the modified papermaking sludge.

[0013] By adopting the above technical solution, sodium carboxymethyl cellulose long-chain molecules are linked to the surface of the activated papermaking mud, which can promote the formation of hydrogen bonding forces between the papermaking mud and the cement matrix and fiber surface, and further improve the strength of lightweight concrete.

[0014] Preferably, the heating temperature is 55-65℃.

[0015] Preferably, the accelerator is polydiallyldimethylammonium chloride, and the mass ratio of the accelerator to sodium carboxymethyl cellulose is (0.3-0.5):1.

[0016] Preferably, the fiber is one of alumina fiber, glass fiber, and silicon carbide fiber.

[0017] Secondly, this application provides a method for preparing a precast interior partition wall panel containing papermaking sludge, using the following technical solution: A method for preparing a prefabricated interior partition wall panel containing papermaking sludge includes the following specific steps: mixing activated papermaking sludge, cement, fly ash, water-reducing agent, fiber and sodium carboxymethyl cellulose to obtain a papermaking sludge lightweight concrete slurry; pouring the papermaking sludge lightweight concrete slurry into a mold to produce a prefabricated interior partition wall panel containing papermaking sludge.

[0018] By adopting the above technical solution, the synergistic effect of each component enhances the bonding between papermaking mud and cement, while reducing plastic shrinkage and drying shrinkage caused by water absorption and evaporation of mud. It forms a uniform three-dimensional network in concrete, inhibits the generation and propagation of microcracks, and improves the density and crack resistance of lightweight concrete.

[0019] In summary, this application has the following beneficial effects: 1. This application utilizes pre-activation of papermaking slurry to enhance the bonding reaction between the slurry and cement. Sodium carboxymethyl cellulose enhances the persistence of the pozzolanic reaction between the slurry and cement, reducing cracking caused by concrete shrinkage. The addition of fibers forms a robust network structure in the concrete system, inhibiting the generation and propagation of microcracks, and improving the density and crack resistance of lightweight concrete.

[0020] 2. In this application, sodium hexametaphosphate and aluminate are used to surface activate papermaking sludge, preventing the agglomeration of papermaking sludge particles and promoting their stable dispersion in the concrete system. The activated papermaking sludge is then reacted with sodium carboxymethyl cellulose for modification, promoting the formation of hydrogen bonds between the papermaking sludge and the cement matrix and fiber surface, further improving the overall density and strength of the lightweight concrete. Detailed Implementation

[0021] The present application will be further described in detail below with reference to the embodiments.

[0022] All raw materials used in the examples are commercially available. Example

[0023] Example 1 This embodiment provides a precast interior partition wall panel containing papermaking sludge. The precast interior partition wall panel is formed by casting lightweight concrete containing papermaking sludge. The lightweight concrete containing papermaking sludge includes the following raw materials in parts by weight: 25 kg activated papermaking sludge, 20 kg cement, 15 kg fly ash, 2 kg water-reducing agent, 7 kg fiber, and 4 kg sodium carboxymethyl cellulose. The water-reducing agent is polycarboxylate superplasticizer PCE-101, the main components of the cement are 62.23 wt% CaO and 22.90 wt% SiO2, and the fiber is glass fiber.

[0024] The activated papermaking white mud raw materials include sodium hexametaphosphate, aluminate and papermaking white mud, with a mass ratio of sodium hexametaphosphate, aluminate and papermaking white mud of 1.2:2:10. The aluminate is DL-411 and the main component of the papermaking white mud is 94.20 wt% CaO.

[0025] The preparation method of precast interior partition wall panels containing papermaking bleach includes the following specific steps: S1: After crushing the papermaking sludge, heat it to 115℃, add sodium hexametaphosphate and aluminate in sequence, and wet grind for 2 hours to obtain activated papermaking sludge.

[0026] S2: Mix activated papermaking mud, cement, fly ash, water-reducing agent, fiber and sodium carboxymethyl cellulose, add water and mix to obtain papermaking mud lightweight concrete slurry, pour the papermaking mud lightweight concrete slurry into the mold to make prefabricated interior partition wall panels.

[0027] Example 2 The difference between Example 2 and Example 1 is that the lightweight concrete containing papermaking sludge includes the following raw materials in parts by weight: 20 kg of activated papermaking sludge, 30 kg of cement, 10 kg of fly ash, 3 kg of water-reducing agent, 5 kg of fiber, and 3 kg of sodium carboxymethyl cellulose.

[0028] Example 3 The difference between Example 3 and Example 1 is that the lightweight concrete containing papermaking sludge includes the following raw materials in parts by weight: 30 kg of activated papermaking sludge, 20 kg of cement, 20 kg of fly ash, 1 kg of water-reducing agent, 8 kg of fiber, and 5 kg of sodium carboxymethyl cellulose.

[0029] Example 4 The difference between Example 4 and Example 1 is that the mass ratio of sodium hexametaphosphate, aluminate and papermaking white mud in the activated papermaking white mud raw material is 0.5:3:10.

[0030] Example 5 The difference between Example 5 and Example 1 is that the mass ratio of sodium hexametaphosphate, aluminate and papermaking white mud in the activated papermaking white mud raw material is 2:1:10.

[0031] Example 6 The difference between Example 6 and Example 1 is that the activated papermaking sludge was modified with sodium carboxymethyl cellulose beforehand.

[0032] The preparation method of precast interior partition wall panels containing papermaking bleach includes the following specific steps: S1: After crushing the papermaking sludge, heat it to 115℃, add sodium hexametaphosphate and aluminate in sequence, and wet grind for 2 hours to obtain activated papermaking sludge.

[0033] S2: After dissolving sodium carboxymethyl cellulose in a water bath, add activated papermaking sludge, and then add the accelerator polydiallyldimethylammonium chloride. The mass ratio of the accelerator to sodium carboxymethyl cellulose is 0.4:1. Keep the mixture at 60°C for 2 hours, and then centrifuge and dry to obtain modified papermaking sludge.

[0034] S2: Mix modified papermaking mud, cement, fly ash, water-reducing agent, and fiber, add water and mix to obtain papermaking mud lightweight concrete slurry. Pour the papermaking mud lightweight concrete slurry into a mold to make a precast interior partition wall panel.

[0035] Example 7 The difference between Example 7 and Example 6 is that, in the process of modifying activated papermaking sludge with sodium carboxymethyl cellulose, the mass ratio of accelerator to sodium carboxymethyl cellulose is 0.3:1.

[0036] Example 8 The difference between Example 8 and Example 6 is that, in the process of modifying activated papermaking sludge with sodium carboxymethyl cellulose, the mass ratio of accelerator to sodium carboxymethyl cellulose is 0.5:1.

[0037] Example 9 The difference between Example 9 and Example 6 lies in the preparation method of the prefabricated interior partition wall panel containing papermaking bleach, which includes the following specific steps: S1: After crushing the papermaking sludge, heat it to 115℃, add sodium hexametaphosphate and aluminate in sequence, and wet grind for 2 hours to obtain activated papermaking sludge.

[0038] S2: After dissolving sodium carboxymethyl cellulose in a water bath, add the activated papermaking mud, stir evenly, keep the reaction at 60°C for 2 hours, and then centrifuge and dry to obtain the modified papermaking mud.

[0039] S2: Modified papermaking mud, cement, fly ash, water-reducing agent, and fiber are mixed with water to obtain papermaking mud lightweight concrete slurry. The papermaking mud lightweight concrete slurry is poured into a mold to make a precast interior partition wall panel.

[0040] Comparative Example Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that sodium carboxymethyl cellulose is not used in the lightweight concrete raw material containing papermaking sludge.

[0041] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the papermaking sludge in the lightweight concrete raw material containing papermaking sludge is not activated.

[0042] The preparation method of precast interior partition wall panels containing papermaking bleach includes the following specific steps: Papermaking slurry, cement, fly ash, water-reducing agent, fiber and sodium carboxymethyl cellulose are mixed and water is added to obtain papermaking slurry lightweight concrete slurry. The papermaking slurry lightweight concrete slurry is poured into molds to make prefabricated interior partition panels.

[0043] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that no fiber is used in the lightweight concrete raw material containing papermaking sludge.

[0044] Performance testing The prefabricated internal partition wall panels containing papermaking sludge provided in Examples 1-9 and Comparative Examples 1-3 of this application were subjected to the following performance tests, and the specific test results are shown in Table 1.

[0045] Detection methods I. Mechanical Properties Referring to the Chinese standard GB / T 50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete", the precast interior partition wall panel containing papermaking slurry prepared in this application was tested for compressive strength, splitting strength and early crack resistance after 28 days of curing.

[0046] Table 1: Performance Test Results Data Table The performance test results show that the precast internal partition wall panel containing papermaking sludge prepared in this application has strong crack resistance and strength, and the activated papermaking sludge has good compatibility and bonding reaction with the cement matrix.

[0047] A comparison of Comparative Examples 1-3 and Example 1 reveals that Comparative Example 1 did not use sodium carboxymethyl cellulose, the papermaking sludge in the lightweight concrete raw material of Comparative Example 2 was not activated, and fiber was not used in Comparative Example 3. Performance testing results show that the precast interior partition wall panel containing papermaking sludge prepared in Comparative Example 1 exhibited decreased overall performance, the crack resistance of the precast interior partition wall panel containing papermaking sludge prepared in Comparative Example 3 decreased significantly, and the strength of the precast interior partition wall panel containing papermaking sludge prepared in Comparative Example 2 decreased significantly, with poor impact resistance and a tendency to crack. This further demonstrates that activated papermaking sludge can undergo a pozzolanic reaction with calcium hydroxide, a hydration product of the cement matrix, to generate additional CSH gel, improving later-stage strength, density, and durability. Sodium carboxymethyl cellulose ensures the continuous pozzolanic reaction between the sludge and cement, reducing drying shrinkage caused by water absorption and evaporation of the sludge. At the same time, the fibers can be combined with papermaking mud and cement machinery to form a network structure in the concrete system, thereby improving the strength and crack resistance of lightweight concrete.

[0048] As shown in Examples 6-9, the activated papermaking sludge was modified with sodium carboxymethyl cellulose beforehand. The performance test results showed that the overall performance of the precast internal partition wall panel containing papermaking sludge was significantly improved. This further illustrates that the long-chain sodium carboxymethyl cellulose molecules linked to the surface of the activated papermaking sludge can effectively improve the strength and mechanical properties of lightweight concrete.

[0049] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A prefabricated interior partition panel comprising papermaking white mud, characterized in that, The prefabricated inner partition wall plate is formed by pouring the papermaking white mud-containing lightweight concrete, and the papermaking white mud-containing lightweight concrete comprises the following raw materials in parts by weight: activated papermaking white mud 20-30 parts, cement 20-30 parts, fly ash 10-20 parts, water reducing agent 1-3 parts, fiber 5-8 parts, and sodium carboxymethyl cellulose 3-5 parts.

2. The precast interior partition panel containing paper mill lime mud according to claim 1, characterized in that, The activated papermaking white mud raw material comprises sodium hexametaphosphate, aluminate and papermaking white mud, and the mass ratio of the sodium hexametaphosphate, aluminate and papermaking white mud is (0.5-2):(1-3):

10.

3. The precast interior partition panel containing paper mill lime mud according to claim 2, characterized in that, The preparation method of the activated papermaking white mud comprises the following specific steps: crushing the papermaking white mud, heating, then adding sodium hexametaphosphate and aluminate in sequence for wet grinding to obtain the activated papermaking white mud.

4. The precast interior partition panel containing paper mill lime mud according to claim 3, characterized in that, The heating temperature is 110-120 DEG C.

5. The precast interior partition panel containing paper mill lime mud according to claim 3, wherein, The activated papermaking white mud is modified with sodium carboxymethyl cellulose in advance, and the modification method comprises the following specific steps: dissolving the sodium carboxymethyl cellulose by water bath heating, then adding the activated papermaking white mud, dropping a promoter, mixing and heat preserving, centrifuging and drying to obtain the modified papermaking white mud.

6. The precast interior partition panel containing paper mill whitewash according to claim 5, characterized in that, The heating temperature is 55-65 DEG C.

7. The precast interior partition panel containing paper mill whitewash according to claim 5, characterized in that, The promoter is polydiallyldimethylammonium chloride, and the mass ratio of the promoter to the sodium carboxymethyl cellulose is (0.3-0.5):

1.

8. The precast interior partition panel containing paper mill whitewash according to claim 1, characterized in that, The fiber is one of alumina fiber, glass fiber and silicon carbide fiber.

9. A method for the production of a prefabricated interior partition panel containing paper mill white lime mud according to any one of claims 1 to 8, characterized in that, The method comprises the following specific steps: mixing the activated papermaking white mud, cement, fly ash, water reducing agent, fiber and sodium carboxymethyl cellulose to obtain papermaking white mud lightweight concrete slurry, and pouring the papermaking white mud lightweight concrete slurry into a mold to form the prefabricated inner partition wall plate.

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