Low-cost slag pot insulating separation spray coating and production and use method thereof

Abstract

The present application relates to a kind of low-cost slag tank heat insulation separation coating material formula and its production method, using main raw material is flue gas desulfurization gypsum, fly ash, dolomite dust, limestone dust and other industrial solid waste around steel plant, compared with using refractory material, substantially reduce the cost of raw materials;At the same time, the main raw material does not need to use grinding process, further reduce cost.When using, the components are mixed while stirring, after stirring evenly, continue to stir for more than 2 hours, get homogeneous coating mortar.Coating mortar is constructed by artificial gunning machine, forms a firm high-temperature resistant, slag erosion resistant coating layer on the inner wall of slag tank, significantly reduces the probability of steel and iron slag sticking to the tank;Without external driving, the tank falls naturally, does not stick to the wall, natural tank turnover rate is 100%, maintains the benign cycle of production process, realizes high turnover efficiency of slag tank and improves the service life of slag tank.

Description

TECHNICAL FIELD

[0001] The present application relates to a low-cost slag tank heat insulation separation coating material, in particular to the coating material formula, preparation and use method. BACKGROUND

[0002] The slag tank is a container for containing high-temperature molten slag generated in the steel smelting process, and plays a role in short-distance transportation in the steel production process. The high-temperature molten slag is cooled and solidified in the slag tank, and is difficult to pour out during the process, resulting in that the slag tank cannot automatically turn the slag, and needs to be treated later, such as separating the steel slag from the slag tank by knocking the slag basin, but knocking the slag tank will damage the slag tank and easily cause the steel slag to splash, causing safety accidents.

[0003] In order to facilitate slag turning, improve the tank turnover rate, effectively reduce the slag tank damage phenomenon, and maintain the benign cycle of the production process, the coating material is generally used for slag tank protection at present to improve the tank life. At present, most of the steel plants use graphite, quicklime, dolomite, magnesia, clay and other resources as the main raw materials of the coating material, which are processed through the grinding process, consuming natural resources and having high overall price.

[0004] The purpose of the present application is to provide a low-cost slag tank heat insulation separation coating material using solid waste and a production method thereof, and the product use target effect is: 1. The cold slag is easily removed from the slag tank without external driving force. 2. Easy to operate, maintain the benign cycle of the production process, realize high turnover efficiency of the slag tank. 3. Effectively reduce the slag tank damage phenomenon. 4. Low use cost. SUMMARY

[0005] The purpose of the present application is to provide a low-cost slag tank heat insulation separation coating material and a production and use method thereof. On the one hand, solid waste materials are used to replace refractory materials, which greatly reduces the cost of raw materials; on the other hand, the grinding process is not needed, which further reduces the production cost.

[0006] The purpose of the application is achieved in that a low-cost slag tank heat insulation separation spray paint, raw materials are flue gas desulfurization gypsum, fly ash, dolomite mine dust, limestone mine dust, graphite dust, industrial cassava starch, water; the raw material ratio is: flue gas desulfurization gypsum 30-40w%, fly ash 15-25w%, dolomite mine dust 10-20w%, limestone mine dust 20-30w%, graphite dust 3-5w%, industrial cassava starch 3-5w%, and water 200-350w%; the chemical mass percentage is: CaO: 8.0-9.0%, MgO: 1.0-2.0%, Al2O3: 1.0-2.0%, Fe2O3: 0.4-0.6%, SiO2: 2.5-3.5%, SO2: 3.5-5.0%, CO2: 4.5-5.5%, H2O: 71.0-73.0%, C: 1.0-1.5%, and the rest is inevitable impurities.

[0007] A production method of a low-cost slag tank heat insulation separation spray paint, comprising the following steps: step one: first stirring and taking slurry: during production, the total weight of each solid raw material component is recorded as 100w%, and 200w% of water is added in the stirrer in sequence, after uniform stirring, stop stirring and wait for 20-40 minutes for complete settlement, take 70-90% of the upper half of the flocculent mortar thick for standby; step two: second stirring and taking slurry: after the first stirring and taking slurry, the remaining mortar with sediment in the lower layer is added with 100w% of water for stirring, after uniform stirring, stop stirring and wait for 20-40 minutes for complete settlement, take 70-90% of the upper half of the flocculent mortar thin for standby again; step three: third stirring and taking slurry: after the second stirring and taking slurry, the remaining mortar with sediment in the lower layer is continuously added with 50w% of water, stop stirring and wait for 20-40 minutes for complete settlement, take 70-90% of the upper half of the flocculent mortar water for next time as raw material water.

[0008] A use method of a low-cost slag tank heat insulation separation spray paint, comprising the following steps: step one: during use, first start the stirrer, inject the obtained flocculent mortar thick, after uniform stirring, do the hanging mortar test; step two: according to the hanging mortar test result of step one, add 3-5w% of the obtained flocculent mortar thin for adjustment, add 2-3 batches, do the hanging mortar test once for each addition of flocculent mortar thin, after the hanging mortar test is qualified, stop adding the flocculent mortar thin, the hanging mortar test qualified standard: wall sticking mortar, mortar can be evenly spread for qualified; step three: after the hanging mortar test is qualified, continue stirring for 1-2 hours to obtain the spray paint mortar; step four: the spray paint mortar is constructed 2-3 times on the inner wall of the slag tank by the artificial patching machine to form a paint layer, when the spray paint mortar is placed for more than 10 minutes and then sprayed again, it needs to be stirred for 5-10 minutes before spraying and then used again.

[0009] The beneficial effects of this invention are: 1. The sprayed mortar is applied by a manual spraying machine to form a strong, high-temperature resistant, and slag-corrosion resistant coating layer on the inner wall of the slag tank, which significantly reduces the probability of steel and iron slag sticking to the tank.

[0010] 2. Without external force, the slag can falls naturally without sticking to the wall, achieving a 100% natural slag can turnover rate, maintaining a virtuous cycle in the production process, realizing high turnover efficiency of slag cans and improving the service life of slag cans.

[0011] 3. The functional structure of this coating layer is clear, with the reaction layer, transition layer, and gradient layer fulfilling their respective functions.

[0012] 4. The manufacturing cost of the spray coating (dry state) is less than 200 yuan / ton, compared with 800-1800 yuan / ton for the same function of spray coating on the market, which greatly reduces the cost of use. Attached Figure Description

[0013] The present invention will now be further described with reference to the accompanying drawings.

[0014] Figure 1 This is a process diagram for the production and use of the present invention.

[0015] Metering Screw Feeder: A type of weighing screw feeder, which is a production metering equipment for continuous conveying, dynamic metering, and controlled feeding of various powdery and granular materials. Detailed Implementation

[0016] The present invention aims to provide a low-cost slag tank insulation and separation spray coating and its production and application process, which facilitates slag turning, increases the turning rate, effectively reduces slag tank damage, and maintains a virtuous cycle in the production process.

[0017] This invention relates to a low-cost slag pot insulation and separation spray coating formulation and its production process. The main raw materials used are fly ash, flue gas desulfurization gypsum, dolomite ore dust, and limestone ore dust, all industrial solid wastes. Compared to using refractory materials, this significantly reduces raw material costs. The formulation is as follows: 30-40w% flue gas desulfurization gypsum, 15-25w% fly ash, 10-20w% dolomite ore dust, 20-30w% limestone ore dust, 3-5w% graphite dust, 3-5w% industrial cassava starch, and 200-350w% water. The spray coating slurry is applied manually using a spraying machine, forming a strong, high-temperature resistant, and slag-corrosion-resistant coating layer on the inner wall of the slag pot, significantly reducing the probability of steel and iron slag sticking to the pot. Without external force, the pot falls naturally without sticking to the wall, achieving a 100% natural pot-turning rate, maintaining a virtuous cycle in the production process, achieving high turnover efficiency of the slag pot, and improving its service life. Its preferred main components are shown in the table below.

[0018]

[0019] Flue gas desulfurization gypsum: the raw material of wet limestone / gypsum method is limestone or lime, which is made into slurry with water, pumped into the absorption tower and mixed with flue gas. Sulfur dioxide in the flue gas reacts with calcium hydroxide in the slurry and air to form calcium sulfate and calcium sulfite. When the saturation degree reaches a certain degree, it is discharged from the absorption tower, then concentrated, dehydrated, and finally crystallized to form a mixture of dihydrate gypsum and calcium sulfite. The main components are as follows.

[0020]

[0021] Dolomite mine dust: fine dust collected from the environmental protection dust collector during the mining, crushing and processing of dolomite mine. The main components are as follows.

[0022]

[0023] Limestone mine dust: fine dust collected from the environmental protection dust collector during the mining, crushing and processing of limestone mine. The main components are as follows.

[0024]

[0025] Graphite dust: fine dust collected from the environmental protection dust collector during the processing of graphite. The main components are as follows.

[0026]

[0027] Fly ash: fine dust collected from the environmental protection dust collector of coal-fired boiler.

[0028]

[0029] The slag tank heat insulation separation coating material involved in the present application has the following functional characteristics: (1) In the low temperature section (0-300℃), industrial tapioca starch paste is added to provide wall adhesion strength and adhesion, to ensure the relative uniform distribution and adhesion of the coating material, and the coating material can form a solid heat-resistant coating layer on the inner wall of the slag tank.

[0030] (2) During the injection of liquid molten slag into the slag tank, dolomite dust generates gas at 690-1100℃, and limestone dust generates gas at 890-1400℃. A large amount of gas makes the structure of the reaction zone loose, facilitating slag turning.

[0031] (3) After the injection of liquid molten slag into the slag tank, at a high temperature of 1200-1400℃, the desulfurization gypsum undergoes dehydration and high-temperature calcination under the action of high-temperature steel slag, and the desulfurization gypsum loses two crystal waters to become half a crystal water, forming mature gypsum. This process expands the volume, promoting the natural separation of the slag tank and the steel slag.

[0032] (4) The main role of graphite dust removal ash is to prevent slag from invading the coating and improve the corrosion resistance of the coating. The principle is that the contact angle of graphite and molten slag is > 90°, and the molten slag cannot enter the capillary of the coating to erode the coating.

[0033] (5) Fly ash is light in quality and poor in adhesion, which can improve the spreadability and fluidity of the thermal insulating agent as raw material, and improve the heat insulation effect; at the same time, the unburned carbon (high ignition point) in the fly ash slowly oxidizes under high-temperature steel slag operation to form gas filling and form a sintered layer of porous structure.

[0034] (6) All the solid products after reaction are high-melting-point products with good sintering performance, forming a structure containing a large amount of high-melting-point substances, which effectively ensures the high-temperature resistance of the coating.

[0035] The production method design for obtaining more than 200 purposes of slag tank heat insulation separation spraying material at low cost is as follows: (1) during production, the total weight of each component is recorded as 100 w%, and 200 w% of water is added in a stirrer in sequence, after stirring uniformly, stopping stirring and waiting for sedimentation, taking about 4 / 5 of the upper half of the flocculent mortar (thick) for standby; (2) the lower 1 / 5 mortar (containing sediment) is added with 100 w% of water for stirring, after stirring uniformly, stopping stirring and waiting for sedimentation, taking about 4 / 5 of the upper half of the flocculent mortar (thin) for standby again; (3) the lower 1 / 5 mortar (containing sediment) after the second time of taking mortar is continuously added with 50 w% of water, and the upper half of the flocculent mortar water is taken as raw material water for next time.

[0036] The whole production process does not need to use a grinding process, compared with the common spraying material crushing and grinding process, the production cost is greatly reduced.

[0037] The use method design of the slag tank heat insulation separation spraying material which is simple and convenient to operate is as follows: (1) during use, the stirrer is started first, and the obtained flocculent mortar (thick) is injected, after stirring uniformly, the mortar is tested; (2) according to the mortar test, the flocculent mortar (thin) obtained in claim 2 is added in batches for adjustment; (3) after the mortar test is qualified, the stirring is continued for more than 2 hours to obtain homogeneous spraying mortar; (4) the spraying mortar is sprayed on the inner wall of the slag tank by a manual spraying machine for 1-2 times to form a firm high-temperature-resistant and slag-erosion-resistant coating layer; (5) after a period of time, the stirring is carried out for more than 5 minutes before spraying, and then the spraying is used again.

[0038] The mortar for the mortar test can be relatively uniformly spread to be qualified.

[0039] Before the implementation of the present application, there are slag sticking wall and melting hole, after the implementation, the slag tank falls naturally without external force, does not stick to the wall, the natural turning rate is 100%, the functional structure of the coating layer is clear, and the reaction layer, the transition layer and the gradient layer realize the function of the slag tank.

[0040] Typical example one: the formula is: flue gas desulfurization gypsum 30w%, fly ash 15w%, dolomite dust 10w%, limestone dust 20w%, graphite dust 3w%, industrial cassava starch 3w% and 200w% water. The product test results are as follows.

[0041]

[0042] After implementation, the tank falls naturally without external force, does not stick to the wall, and the natural tank turnover rate is 100%; the functional structure of the coating layer is clear, and the reaction layer, transition layer and gradient layer realize the function effect.

[0043] Typical example two: the formula is: flue gas desulfurization gypsum 40w%, fly ash 25w%, dolomite dust 20w%, limestone dust 30w%, graphite dust 3w%, industrial cassava starch 3w% and 300w% water. The product test results are as follows.

[0044]

[0045] After implementation, the tank falls naturally without external force, does not stick to the wall, and the natural tank turnover rate is 100%; the functional structure of the coating layer is clear, and the reaction layer, transition layer and gradient layer realize the function effect.

[0046] Typical example three: the preferred formula is: flue gas desulfurization gypsum 34w%, fly ash 20w%, dolomite dust 15w%, limestone dust 25w%, graphite dust 3w%, industrial cassava starch 3w% and 250w% water. The product test results are as follows.

[0047]

[0048] After implementation, the tank falls naturally without external force, does not stick to the wall, and the natural tank turnover rate is 100%; the functional structure of the coating layer is clear, and the reaction layer, transition layer and gradient layer realize the function effect.

[0049] The above only describes specific embodiments of the present application, but the structural features of the scope of protection of the present application are not limited to this, any changes or modifications made by those skilled in the art within the scope of the present application are covered by the patent scope of the present application.

Claims

1. A low cost ladle insulation and separation coating characterized by: The raw materials are flue gas desulfurization gypsum, fly ash, dolomite dust, limestone dust, graphite dust, industrial cassava starch, and water. The raw material ratio is: flue gas desulfurization gypsum 30-40w%, fly ash 15-25w%, dolomite dust 10-20w%, limestone dust 20-30w%, graphite dust 3-5w%, industrial cassava starch 3-5w%, and water 200-350w%. The total weight of each solid raw material component is 100w%. The chemical composition mass percentage is: CaO: 8.0-9.0%, MgO: 1.0-2.0%, Al2O3: 1.0-2.0% Fe2O3: 0.4-0.6%, SiO2: 2.5-3.5%, SO2: 3.5-5.0%, CO2: 4.5-5.5%, H2O: 71.0-73.0%, C: 1.0-1.5%, and the rest is unavoidable impurities.

2. A method of producing a low-cost, slag-tap-insulated, separate, sprayable coating for a slag pot according to claim 1, characterized in that: The steps include: Step one: First stirring and taking slurry: During production, the total weight of each solid raw material component is 100w%, and 200w% of water is added in the stirrer in sequence. After stirring evenly, stop stirring and wait for 20-40 minutes for complete settlement. Take the upper 70-90% of the flocculent mortar and reserve it for use. Step two: Second stirring and taking slurry: After the first stirring and taking slurry, the remaining mortar with sediment in the lower layer is added with 100w% water and stirred. After stirring evenly, stop stirring and wait for 20-40 minutes for complete settlement. Take the upper 70-90% of the flocculent mortar again and reserve it for use. Step three: Third stirring and taking slurry: After the second stirring and taking slurry, the remaining mortar with sediment in the lower layer is continuously added with 50w% water. Stop stirring and wait for 20-40 minutes for complete settlement. Take the upper 70-90% of the flocculent mortar again and reserve it for use as the water for the next batch of raw materials.

3. The method of claim 1, wherein the method further comprises: applying a low cost slag pot insulating coating to the slag pot. The steps include: ​ Step one: When in use, first start the stirrer and inject the obtained flocculent mortar. After stirring evenly, conduct a hanging slurry test. Step two: According to the results of the hanging slurry test in step one, add 3-5w% of the obtained flocculent mortar for adjustment. Add 2-3 batches, and conduct a hanging slurry test after adding the flocculent mortar each time. After the hanging slurry test is qualified, stop adding the flocculent mortar. The qualified standard for the hanging slurry test is that the mortar can spread evenly on the wall. Step three: After the hanging slurry test is qualified, continue stirring for 1-2 hours to obtain the sprayable mortar. Step four: The sprayable mortar is sprayed on the inner wall of the slag tank for 2-3 times to form a coating layer. If the sprayable mortar is placed for more than 10 minutes before spraying, it needs to be stirred for 5-10 minutes before use.

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