Cast iron release agent as well as preparation method and application thereof

Abstract

The invention provides a cast iron release agent and a preparation method and application thereof. The cast iron release agent comprises the following raw materials in parts by weight: 10-13 parts of coking plant fly ash, 3-6 parts of bentonite, 3-6 parts of pyrophyllite and 75-88 parts of water. According to the cast iron release agent, the fly ash of a coking plant is used as a raw material, the production cost is low, meanwhile, the environmental protection pressure of the coking plant is relieved, and the purposes of reducing cost and improving efficiency are achieved; the cast iron release agent is good in integrality and long in service life, and can be effectively attached to the inner surface of a casting mold, so that an effective isolation layer is formed between molten iron and the casting mold, a cast iron machine can demold without additional knocking, a cast iron ingot is smooth in surface and low in iron loss, the cast iron cost is reduced, and the application prospect is wide.

Description

Technical Field

[0001] The invention relates to the technical field of cast iron, and in particular to a cast iron release agent and a preparation method and application thereof. Background Art

[0002] The cast iron machine is a device for casting pig iron blocks. The cast iron machine is an important equipment for blast furnace cast iron. Whether its running stability is good is directly related to the continuity of cast iron production and the improvement of cast iron efficiency. The cast iron machine consists of a circulating chain belt equipped with a series of casting molds. The molten iron is injected into the running casting mold one by one at one end, and the casting mold is cooled during operation. When it reaches the tail of the cast iron machine and moves in the opposite direction, the solidified iron block automatically falls off from the casting mold. However, due to the continuous operation of the cast iron machine, some iron blocks that are not easy to fall off will be cleaned and fallen off by the iron stripping device. When the chain belt returns, in order to facilitate the demolding of the iron blocks, slurry (i.e., demolding agent) will be continuously sprayed into the mold of the cast iron machine when the cast iron machine is running. However, the demolding agent commonly used at present has a low lifespan and poor effect, and needs to rely on the iron stripping device to clean the iron blocks; during cleaning, the iron stripping device will collide with the cast iron mold. After long-term use, not only does the iron stripping device need to be replaced, but the mold will also be damaged.

[0003] CN110090918A discloses a cast iron release agent and its production process, the composition and mass percentage of each component of the release agent are: 0.5-1% graphite, 0-0.5% coke powder, 5-10% Guangxi white mud, 2-5% sericite, 1-2% coal slime and 82-90% water. The above release agent has the advantages of strong adhesion, fast sintering speed, ceramicization after sintering, and can be sprayed in the cast iron process with good spraying effect. However, during use, high-temperature steam is needed to heat the slurry to 80-90°C, which has certain safety risks; in addition, the volatilization of coal slime liquid will produce unpleasant gas, which is easy to cause environmental pollution.

[0004] CN102974752A discloses a mold release agent for cast iron machine, each component is composed of the following parts by mass: 20-25 parts of blast furnace gas mud, 10-13 parts of sintering machine head electric dust removal ash, 16-23 parts of furnace front ore trough dust removal ash, 15-17 parts of soybean oil, 5-7 parts of limestone, 9-10 parts of aluminum oxide, 11-15 parts of dolomite, 17-19 parts of bentonite, 7-8 parts of iron red epoxy ester primer, 3-5 parts of zirconium oxide, and 800-1000 parts of water. The above-mentioned mold release agent recycles dust removal ash such as blast furnace gas mud and sintering machine head in steel plants, but its ratio is complicated, and the dust removal ash contains oxides of tin, zinc, lead, aluminum, etc. and part of CaO components, which need to be processed in advance before use, and the production cost is high.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide a cast iron release agent and a preparation method and application thereof. The cast iron release agent has good integrity, long service life, good use effect on cast iron machines, and reduces cast iron costs.

[0007] The invention provides a cast iron mold release agent, which comprises the following raw materials in parts by weight: 10-13 parts of dust removal ash from a coking plant, 3-6 parts of bentonite, 4-6 parts of pyrophyllite and 75-88 parts of water.

[0008] Preferably, the cast iron release agent of the present invention comprises the following raw materials in parts by weight: 10-13 parts of coking plant dust, 4-6 parts of bentonite, 3-6 parts of pyrophyllite and 77-80 parts of water.

[0009] Specifically, the particle size of the coking plant dust is less than 325 mesh; the mass content of carbon (C) in the coking plant dust is ≥40%, for example, 40-60%, and further 40-44%. Studies have shown that the carbon-containing substances in the coking plant dust can improve the anti-sticking performance of the cast iron release agent; due to its low fineness, it can be fully mixed with water to form a colloid, without heating and continuous stirring to increase the uniformity of the slurry; in addition, the low fineness enables the cast iron release agent to effectively adhere to the inner surface of the mold, forming an effective isolation layer between the molten iron and the mold, and the cast iron machine can be demolded without additional knocking, and the surface of the cast iron ingot is smooth and the cast iron quality is high.

[0010] The particle size of bentonite is less than 325 mesh; the mass content of silicon dioxide (SiO2) in bentonite is ≥40%, for example, 40-55%, and further 40-46%. Studies have shown that bentonite can improve the lubricity of the slurry, so that it can be sprayed more conveniently without clogging the spray gun; in addition, bentonite has viscosity, which can make the cast iron release agent better adhere to the mold. The amount of bentonite added is preferably 3-6%. Too much addition will lead to too high viscosity of the slurry and increase the spraying pressure; too little addition will not easily adhere to the mold, thereby reducing the life of the release agent.

[0011] The pyrophyllite can be waxy pyrophyllite; the particle size of the pyrophyllite is less than 325 mesh; the mass content of silicon dioxide (SiO2) in the pyrophyllite is ≥30%, for example, 38-45%. Studies have shown that pyrophyllite can increase the sintering performance of the cast iron release agent, and the pyrophyllite has little expansion after being heated, which is beneficial to improving the integrity of the cast iron release agent, thereby increasing the life of the cast iron release agent. The addition amount of pyrophyllite is preferably 3-6%. Too much addition will lead to insufficient slurry fluidity, and too little addition will lead to the lack of sintering performance of the cast iron release agent, thereby reducing the life of the cast iron release agent.

[0012] The present invention also provides a method for preparing the cast iron release agent, comprising: mixing and stirring coking plant dust, bentonite and pyrophyllite by weight, then adding water by weight and continuing to mix and stir; wherein the mixing and stirring time can be 0.5-1.5 minutes, and the continued mixing and stirring time can be 2-4 minutes.

[0013] The invention also provides application of the cast iron release agent in cast iron.

[0014] Specifically, the cast iron mold release agent is placed in a spraying pool below the iron casting machine, and the cast iron mold release agent is evenly sprayed onto the inner surface of the mold at a spraying pressure of 0.1-0.3 MPa.

[0015] The implementation of the present invention has at least the following advantages:

[0016] 1. The cast iron release agent recovery coking plant of the present invention uses electrostatic dust removal to collect dust ash in the flue gas, which not only has low production costs, but also reduces the environmental pressure of the coking plant, achieves the purpose of reducing costs and increasing efficiency, and has good environmental protection.

[0017] 2. The cast iron release agent of the present invention has a simple composition and a reasonable ratio. The dust removal ash from the coking plant improves the anti-sticking performance of the cast iron release agent to molten iron, the bentonite improves the adhesion between the cast iron release agent and the mold, and the pyrophyllite enhances the spraying performance of the cast iron release agent, and the use effect on the cast iron machine is excellent.

[0018] 3. The preparation method of the cast iron release agent of the present invention is simple. It only needs to mix and stir the raw materials to prepare a slurry with good uniformity. During use, no heating is required. The cast iron release agent only needs to be evenly sprayed onto the inner surface of the mold, which reduces safety risks.

[0019] 4. The cast iron release agent of the present invention has good integrity during use and a long service life. It can effectively adhere to the inner surface of the mold, thereby forming an effective isolation layer between the molten iron and the mold. The cast iron machine can be demolded without additional knocking. The cast iron ingot has a smooth surface and low iron loss, which reduces the cost of cast iron and has broad application prospects. DETAILED DESCRIPTION

[0020] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0021] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this description, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] 12 parts by weight of coking plant dust ash with a particle size of less than 325 mesh (C content of 41-43%), 5 parts by weight of bentonite with a particle size of less than 325 mesh (SiO2 content of 40-45%), and 5 parts by weight of pyrophyllite with a particle size of less than 325 mesh (SiO2 content of 40-45%) that have passed the inspection are sent into a planetary mixer for mixing and stirring. After mixing and stirring for 1 minute, 78 parts by weight of water are added and stirring is continued for 3 minutes to obtain a cast iron release agent.

[0025] The mixed cast iron release agent slurry is placed in the spraying pool below the cast iron machine and sprayed at a pressure of 0.2 MPa, and then the pig iron blocks are cast in a conventional manner.

[0026] The study shows that the surface of the cast iron block cast using the cast iron release agent of this embodiment is smooth, and the iron loss and the number of times it did not automatically fall off during 2 hours of use are shown in Table 1; compared with the control example 1 that does not use the cast iron release agent, the iron loss of this embodiment is reduced by 68%, and the number of times it did not automatically fall off during 2 hours of use is reduced from 9 times to 1 time.

[0027] Example 2

[0028] 10 parts by weight of coking plant dust ash with a particle size of less than 325 mesh (C content of 42-44%), 6 parts by weight of bentonite with a particle size of less than 325 mesh (SiO2 content of 43-46%), and 4 parts by weight of pyrophyllite with a particle size of less than 325 mesh (SiO2 content of 38-43%) that have passed the inspection are sent into a planetary mixer for mixing and stirring. After mixing and stirring for 1 minute, 80 parts by weight of water are added and stirring is continued for 3 minutes to obtain a cast iron release agent.

[0029] The mixed cast iron release agent slurry is placed in the spraying pool below the cast iron machine and sprayed at a pressure of 0.1 MPa, and then the pig iron blocks are cast in a conventional manner.

[0030] The study shows that the surface of the cast iron block cast using the cast iron release agent of this embodiment is smooth, and the iron loss and the number of times it did not automatically fall off during 2 hours of use are shown in Table 1; compared with the control example 2 using steelmaking dust ash instead of coking plant dust ash, the iron loss of this embodiment is reduced by 53%, and the number of times it did not automatically fall off during 2 hours of use is reduced from 9 times to 2 times.

[0031] Example 3

[0032] 13 parts by weight of coking plant dust ash with a particle size of less than 325 mesh (C content of 40-41%), 4 parts by weight of bentonite with a particle size of less than 325 mesh (SiO2 content of 40-45%), and 6 parts by weight of pyrophyllite with a particle size of less than 325 mesh (SiO2 content of 40-45%) that have passed the inspection are sent into a planetary mixer for mixing and stirring. After mixing and stirring for 1 minute, 77 parts by weight of water are added and stirring is continued for 3 minutes to obtain a cast iron release agent.

[0033] The mixed cast iron release agent slurry is placed in the spraying pool below the cast iron machine and sprayed at a pressure of 0.1 MPa, and then the pig iron blocks are cast in a conventional manner.

[0034] The study shows that the surface of the cast iron block cast using the cast iron release agent of this embodiment is smooth, and the iron loss and the number of times it did not automatically fall off during 2 hours of use are shown in Table 1; compared with the control example 3 using clay instead of phyllite, the iron loss of this embodiment is reduced by 64%, and the number of times it did not automatically fall off during 2 hours of use is reduced from 11 times to 2 times.

[0035] Comparative Example 1

[0036] Except that no cast iron release agent is used, the rest is the same as Example 1; the iron loss of this comparative example and the number of times that it did not automatically fall off during the 2-hour use are shown in Table 1.

[0037] Comparative Example 2

[0038] Except for using steelmaking dust ash with consistent fineness (C content of 0.5-2%) instead of coking plant dust ash, the rest is the same as Example 2; the iron loss of this reference example and the number of times it did not automatically fall off during 2 hours of use are shown in Table 1.

[0039] Comparative Example 3

[0040] Except for using clay instead of pyrophyllite, the rest is the same as Example 3; the iron loss of this comparative example and the number of times that it did not automatically fall off during the 2-hour use are shown in Table 1.

[0041] Table 1 Effects of various cast iron release agents

[0042]

[0043]

[0044] In summary, the cast iron release agent of the present invention has a good effect on the use of cast iron machines, reduces the cost of cast iron, and has a favorable impact on energy conservation, emission reduction and environmental protection pressure in coking plants, and has broad application prospects.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A cast iron release agent, characterized in that The method comprises the following raw materials in parts by weight: 10-13 parts of dust removed from a coking plant, 3-6 parts of bentonite, 3-6 parts of pyrophyllite and 75-88 parts of water.

2. The cast iron release agent according to claim 1, characterized in that The particle size of dust removed from the coking plant is less than 325 mesh.

3. The cast iron release agent according to claim 1, characterized in that The mass content of carbon in the dust from the coking plant is ≥40%.

4. The cast iron release agent according to claim 1, characterized in that The particle size of bentonite is less than 325 mesh.

5. The cast iron release agent according to claim 1, characterized in that The mass content of silicon dioxide in bentonite is ≥40%.

6. The cast iron release agent according to claim 1, characterized in that The particle size of pyrophyllite is less than 325 mesh.

7. The cast iron release agent according to claim 1, characterized in that The mass content of silicon dioxide in pyrophyllite is ≥30%.

8. The method for preparing the cast iron release agent according to any one of claims 1 to 7, characterized in that: include: The dust removal ash from the coking plant, bentonite and pyrophyllite are mixed and stirred according to parts by weight, and then water is added according to parts by weight and the mixture is continued to be mixed and stirred to prepare a cast iron release agent.

9. Use of the cast iron release agent according to any one of claims 1 to 7 in cast iron.

10. The use according to claim 9, characterized in that: Place the cast iron release agent in the spraying pool below the cast iron machine, and spray the cast iron release agent evenly onto the inner surface of the mold with a spraying pressure of 0.1-0.3MPa.

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