Hot repair material of refractory materials

Abstract

A hot repair material of refractory materials is provided and includes main materials and binding agents. The main materials include silicon carbide powders with six different particle sizes and a mass ratio according to particle sizes from large to small is 8:5:8:15:8:10. The binding agents include silicon nitride powders, a sodium silicate powder, an aluminum phosphate powder, a furfuryl alcohol, a silicone resin powder, a silica sol powder, an aluminum sol powder, a silicon oxide micronized powder, a vanadium oxide powder, a silicon powder, a borax and a rare earth oxide micronized powder, and a corresponding mass ratio is 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5. The silicon carbide powders in the main materials have a good synergistic effect to improve strength of the repair material. The binding agents include low-, medium- and high-temperature binding agents for a full range of temperatures, so the repair material could gain strength continuously without a collapse temperature.

Claims

1. A hot repair material of refractory materials, comprising main materials and binding agents as raw materials, wherein the main materials comprise silicon carbide powders with different particle sizes, and the binding agents comprise silicon nitride powders, a sodium silicate powder, an aluminum phosphate powder, a furfuryl alcohol, a resin powder, sol powders, a silicon oxide micronized powder, a vanadium oxide powder, a silicon powder, a borax and a rare earth oxide micronized powder; wherein a particle size of each of the silicon carbide powders with the different particle sizes is 3-0.038 millimeters (mm), and the silicon carbide powders with the different particle sizes comprise silicon carbides with six different particle sizes; wherein the six different particle sizes are six selected from the group consisting of 2.5-3 mm, 2-2.5 mm, 1.25-2 mm, 1-1.25 mm, 0.9-1 mm, 0.8-0.9 mm, 0.6-0.8 mm, 0.5-0.6 mm, 0.4-0.5 mm, 0.3-0.4 mm, 0.25-0.3 mm, 0.2-0.25 mm, 0.15-0.2 mm, 0.1-0.15 mm, 0.044-0.074 mm and 0.038-0.044 mm; wherein a particle size of each of the silicon nitride powders is less than or equal to 0.5 mm, the silicon nitride powders comprise silicon nitrides with two different particle sizes, and the two different particle sizes are selected from one of following four types: less than or equal to 0.044 mm and 0.044-0.15 mm, less than or equal to 0.044 mm and 0.15-0.25 mm, less than or equal to 0.044 mm and 0.25-0.4 mm, and less than or equal to 0.044 mm and 0.4-0.5 mm; wherein a mass ratio of the silicon nitrides with the two different particle sizes according to particle sizes from large to small is 10:10; and wherein a mass ratio of the silicon carbides with the six different particle sizes according to particle sizes from large to small is 8:5:8:15:8:10.

2. The hot repair material of refractory materials according to claim 1, wherein the resin powder is a silicone resin powder, and the sol powders comprise a silica sol powder and an aluminum sol powder.

3. The hot repair material of refractory materials according to claim 1, wherein particle sizes of the sodium silicate powder, the aluminum phosphate powder, the resin powder, the sol powders, the vanadium oxide powder and the borax are less than or equal to 0.074 mm, a particle size of the silicon powder is less than or equal to 0.044 mm, a particle size of the silicon oxide micronized powder is less than or equal to 5 micrometers (m) and a particle size of the rare earth oxide micronized powder is less than or equal to 3 rm.

4. The hot repair material of refractory materials according to claim 3, wherein a mass ratio of the silicon nitride powders, the sodium silicate powder, the aluminum phosphate powder, the furfuryl alcohol, the silicone resin powder, the silica sol powder, the aluminum sol powder, the silicon oxide micronized powder, the vanadium oxide powder, the silicon powder, the borax and the rare earth oxide micronized powder is 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5.

5. The hot repair material of refractory materials according to claim 1, wherein the refractory materials comprise a silicon carbide refractory material in a supercharged boiler.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In order to more clearly explain the embodiments of the application or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and for ordinary technicians in the field, other drawings could be obtained according to these drawings without creative efforts.

(2) FIG. 1 illustrates a XRD (x-Ray Diffraction) pattern of the repair material prepared in Embodiment 1 after sintering at high temperature.

(3) FIG. 2 illustrates a XRD pattern of the repair material prepared in Embodiment 2 after sintering at high temperature.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(4) Now various exemplary embodiments of the application will be described in detail. This detailed description should not be considered as a limitation of the application, but should be understood as a more detailed description of some aspects, characteristics and embodiments of the application.

(5) It should be understood that the terms used in this application are only for describing specific embodiments, and are not used to limit the application. In addition, for the numerical range in the application, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. Any stated value or intermediate value within the stated range and any other stated value or every smaller range between intermediate values within the stated range are also included in the application. The upper and lower limits of these smaller ranges could be independently included or excluded from the range.

(6) Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the related art. Although the application only describes the preferred methods and materials, any methods and materials similar or equivalent to those described herein could also be used in the practice or testing of the application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and/or materials related to the documents. In case of conflict with any incorporated documents, the contents of this description shall prevail.

(7) Without departing from the scope or spirit of the application, it is obvious to those skilled in the related art that many modifications and changes can be made to the specific embodiments of the application. Other embodiments obtained from the description of the application will be obvious to those skilled in the related art. The description and embodiments of that application are exemplary only.

(8) The words “including”, “comprising”, “having” and “containing” used in this paper are all open terms, that is, they mean including but not limited to.

Embodiment 1

(9) Silicon carbide powders with particle sizes of 1-1.25 mm, 0.5-0.6 mm, 0.25-0.3 mm, 0.1-0.15 mm, 0.044-0.074 mm and 0.038-0.044 mm are separately screened with a sieve and weighed as the main materials of repair material, and the corresponding mass ratio is 8:5:8:15:8:10. Silicon nitride powders, sodium silicate powder, aluminium phosphate powder, furfuryl alcohol, silicone resin powder, silica sol powder, aluminium sol powder, silicon oxide micronized powder, vanadium oxide powder, silicon powder, borax and rare earth oxide micronized powder with a mass ratio of 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5 are used as binding agents; among them, the particle sizes of silicon nitride powders are 0.044-0.15 mm and less than or equal to 0.044 mm, corresponding to a mass ratio of 10:10; the particle sizes of sodium silicate powder, aluminum phosphate powder, organic silicon resin powder, silica sol powder, aluminum sol powder, vanadium oxide powder and borax are less than or equal to 0.074 mm, the particle size of silicon oxide micronized powder is less than or equal to 5 m, the particle size of rare earth oxide micronized powder is less than or equal to 3 m, and the particle size of silicon powder is less than or equal to 0.044 mm.

(10) The above powders are fully mixed and stirred in proportion to obtain repair material, which are packaged and stored, and furfuryl alcohol as a liquid raw material is added before use.

(11) The repair material prepared in this embodiment is sintered at 1,300° C. for 4 h, and then subjected to chemical analysis and XRD detection. The composition of the repair material sintered at high temperature is shown in Table 1, and the XRD pattern is shown in FIG. 1.

(12) TABLE-US-00001 TABLE 1 Composition SiO.sub.2 Al.sub.2O.sub.3 Fe.sub.2O.sub.3 FeO MgO CaO Na.sub.2O Content 45.72 39.51 1.08 0.73 0.29  1.84  0.36 (wt %) Composition K.sub.20 H.sub.2O.sup.+ H.sub.2O.sup.− TiO.sub.2 P.sub.2O.sub.5 MnO Loss Content  0.61  4.94 1.32 1.77 0.051 0.013 0.39 (wt %)

Embodiment 2

(13) The silicon carbide powders with particle sizes of 1.25-2 mm, 0.6-0.8 mm, 0.3-0.4 mm, 0.15-0.2 mm, 0.044-0.074 mm and 0.038-0.044 mm are separately screened by a sieve and weighed as the main materials of the repair material, and the corresponding mass ratio is 8:5:8:15:8:10. Silicon nitride powders, sodium silicate powder, aluminium phosphate powder, furfuryl alcohol, silicone resin powder, silica sol powder, aluminium sol powder, silicon oxide micronized powder, vanadium oxide powder, silicon powder, borax and rare earth oxide micronized powder are selected as binding agents in the mass ratio of 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5. Among them, the particle sizes of silicon nitride powders are 0.15-0.25 mm and less than or equal to 0.044 mm, and the corresponding mass ratio is 10:10; the particle sizes of sodium silicate powder, aluminium phosphate powder, silicone resin powder, silica sol powder, aluminium sol powder, vanadium oxide powder and borax are less than or equal to 0.074 mm; the particle size of silicon oxide micronized powder is less than or equal to m; the particle size of rare earth oxide micronized powder is less than or equal to 3 m; and the particle size of silicon powder is less than or equal to 0.044 mm.

(14) The above powders are fully mixed and stirred in proportion to obtain repair materials, which are packaged and stored, and furfuryl alcohol as a liquid raw material is added before use.

(15) The repair material prepared in this embodiment is sintered at 1,400° C. for 4 h and then detected by XRD. The XRD pattern is shown in FIG. 2.

Embodiment 3

(16) Silicon carbide powders with particle sizes of 2-2.5 mm, 0.8-0.9 mm, 0.4-0.5 mm, 0.2-0.25 mm, 0.044-0.074 mm and 0.038-0.044 mm are separately screened with a sieve and weighed as the main materials of repair material, and the corresponding mass ratio is 8:5:8:15:8:10. Silicon nitride powders, sodium silicate powder, aluminium phosphate powder, furfuryl alcohol, silicone resin powder, silica sol powder, aluminium sol powder, silicon oxide micronized powder, vanadium oxide powder, silicon powder, borax and rare earth oxide micronized powder are selected as binding agents in the mass ratio of 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5. Among them, the particle sizes of silicon nitride powders are 0.25-0.4 mm and less than or equal to 0.044 mm, and the corresponding mass ratio is 10:10; the particle sizes of sodium silicate powder, aluminium phosphate powder, silicone resin powder, silica sol powder, aluminium sol powder, vanadium oxide powder and borax are less than or equal to 0.074 mm; the particle size of silicon oxide micronized powder is less than or equal to 5 m; the particle size of rare earth oxide micronized powder is less than or equal to 3 m; and the particle size of silicon powder less than or equal to 0.044 mm.

(17) The above powders are fully mixed and stirred in proportion to obtain repair material, which is packaged and stored, and furfuryl alcohol as a liquid raw material is added before use.

Embodiment 4

(18) The silicon carbide powders with particle sizes of 2.5-3 mm, 0.9-1 mm, 0.4-0.5 mm, 0.2-0.25 mm, 0.044-0.074 mm and 0.038-0.044 mm are separately screened by a sieve and weighed as the main materials of the repair material, and the corresponding mass ratio is 8:5:8:15:8:10. Silicon nitride powders, sodium silicate powder, aluminium phosphate powder, furfuryl alcohol, silicone resin powder, silica sol powder, aluminium sol powder, silicon oxide micronized powder, vanadium oxide powder, silicon powder, borax and rare earth oxide micronized powder are selected as binding agents in the mass ratio of 20:10:4:1:5:1:1:2:0.5:0.5:0.5:0.5. Among them, the particle sizes of silicon nitride powders are 0.4-0.5 mm and less than or equal to 0.044 mm, and the corresponding mass ratio is 10:10; the particle sizes of sodium silicate powder, aluminium phosphate powder, silicone resin powder, silica sol powder, aluminium sol powder, vanadium oxide powder and borax are less than or equal to 0.074 mm; the particle size of silicon oxide micronized powder is less than or equal to 5 μm; the particle size of rare earth oxide micronized powder is less than or equal to 3 μm; and the particle size of silicon powder is less than or equal to 0.044 mm.

(19) The above powders are fully mixed and stirred in proportion to obtain the repair material, which is packaged and stored, and furfuryl alcohol as a liquid raw material is added before use.

Comparative Embodiment 1

(20) Comparative embodiment 1 is carried out in the same way as Embodiment 1 except that the main materials are all silicon carbide powder with a particle size of 1-1.25 mm, the amount of which is the total amount of the silicon carbide powders of six different particle sizes in Embodiment 1.

Comparative Embodiment 2

(21) Comparative embodiment 2 is carried out in the same way as Embodiment 1, except that silicon nitride powder uses only silicon nitride powder with a particle size of 0.044-0.15 mm, and the amount of silicon nitride powder used is the total amount of silicon nitride powders with the two different particle sizes in Embodiment 1.

Comparative Embodiment 3

(22) Comparative embodiment 3 is carried out in the same way as Embodiment 1, except that the silicone resin powder is not used.

Comparative Embodiment 4

(23) Comparative embodiment 4 is carried out in the same way as Embodiment 1, except that the silica sol powder and the aluminium sol powder are not used.

Comparative Embodiment 5

(24) Comparative embodiment 5 is carried out in the same way as Embodiment 1, except that the silicon oxide micronized powder and the vanadium oxide powder are not used.

(25) Effect Verification

(26) The repair materials prepared in Embodiments 1-4 and Comparative embodiments 1-5 are selected to test their binding strength and flexural strength.

(27) According to GB/T 8642-2002 and GB/T 4513.6-2017, the binding strength and flexural strength of the repair materials are tested respectively. The detailed test results are shown in Table 2:

(28) TABLE-US-00002 TABLE 2 Binding strength Flexural strength (MPa) (MPa) Embodiment 1 6.3 48.1 Embodiment 2 5.9 46.9 Embodiment 3 6.0 44.7 Embodiment 4 5.5 41.9 Comparative embodiment 1 4.0 32.6 Comparative embodiment 2 5.1 40.2 Comparative embodiment 3 4.5 38.8 Comparative embodiment 4 4.1 34.7 Comparative embodiment 5 4.3 36.3

(29) It could be seen from the test results in Table 2 that the repair material, which is obtained by selecting six kinds of silicon carbide powder with different particle sizes as the main materials, has better performance than that of the repair material obtained by selecting only one kind of silicon carbide powder as the main material, proving that the silicon carbide powders with different particle sizes in the main material has good synergy and could strengthen the strength of the repair material. The performance of the repair material obtained by selecting two different silicon nitride powder with different particle sizes is better than that obtained by selecting only one kind of silicon nitride powder with one particle size, showing that the silicon nitride powder with different particle sizes in the binding agent has a limited synergistic effect, and could improve the performance of the repair material to a certain extent. Performance of the repair material could be impaired by omitting any of the low-temperature binding agent silicone resin, medium-temperature binding agent silica sol and aluminium sol, and high-temperature binding agent silicon oxide micronized powder and vanadium oxide powder, indicating that the low-temperature binding agent, medium-temperature binding agent and high-temperature binding agent components in the repair material in synergy to ensure that the material could continuously gain strength at different temperatures, thus enabling the repair material to have better service performance. Silicon carbide powders of different particle sizes in the main material, silicon nitride powders of different particle sizes in the binding agent, as well as low-temperature binding agent, medium-temperature binding agent and high-temperature binding agent in the binding agent act synergistically to achieve the best performance of the repair material.

(30) The foregoing are only preferred embodiments of the application and are not intended to limit the application. Any modifications, equivalent substitutions and improvements etc. made within the spirit and principles of the application shall fall in the scope of protection of the application.