阅读说明：本技术 一种水泥窑用耐高温材料抗结皮性能评价方法 (Method for evaluating anti-skinning performance of high-temperature-resistant material for cement kiln ) 是由 王林俊 苏玉柱 陈旭峰 温晓庆 李燕京 陈昌峰 李寅明 战佳宇 魏丹 冯杰 高长 于 2020-05-11 设计创作，主要内容包括：本发明涉及一种水泥窑用耐高温材料抗结皮性能评价方法,将结皮料饼置于耐高温材料样品的表面,在高温下进行烧成,得到抗结皮样品；采用压缩气体对所述抗结皮样品进行喷吹,对剩余抗结皮样品进行称重,然后对耐高温材料抗结皮性能进行评价。本发明提供的耐高温材料抗结皮性能评价方法具有可重复性高、受环境因素影响小、操作简单,能很好的评价耐高温材料的抗结皮性能。(The invention relates to a method for evaluating the anti-skinning performance of a high-temperature resistant material for a cement kiln, which comprises the steps of placing a skinning material cake on the surface of a high-temperature resistant material sample, and sintering at a high temperature to obtain an anti-skinning sample; and blowing the anti-skinning sample by using compressed gas, weighing the rest anti-skinning sample, and evaluating the anti-skinning performance of the high-temperature resistant material. The method for evaluating the anti-skinning performance of the high-temperature resistant material provided by the invention has the advantages of high repeatability, small influence of environmental factors, simplicity in operation and capability of well evaluating the anti-skinning performance of the high-temperature resistant material.)

1. A method for evaluating the anti-skinning performance of a high-temperature resistant material for a cement kiln is characterized in that a skinning material cake is placed on the surface of a high-temperature resistant material sample and is sintered at high temperature to obtain an anti-skinning sample; and then, blowing the anti-skinning sample by adopting compressed gas, weighing the rest anti-skinning sample, and then evaluating the anti-skinning performance of the high-temperature resistant material.

2. The method of claim 1, comprising the steps of:

step 1), preparing a high-temperature resistant material sample and a crusted cake: providing a high-temperature-resistant material sample and a crusting cake, and weighing the high-temperature-resistant material sample and the crusting cake:

step 2), sintering an anti-skinning sample: placing the crusting material cake on the surface of the high-temperature-resistant material sample, and sintering at high temperature to obtain an anti-crusting sample;

step 3), anti-skinning sample injection treatment: blowing the anti-skinning sample in the step 2) by using compressed gas, and weighing the rest anti-skinning sample;

and 4), evaluating the anti-skinning performance of the high-temperature resistant material according to the following formula:

in the formula, m₁Is the mass of the refractory material sample, m₂M is the mass of the crust cake₃The mass of the remaining anti-skinning sample is and J is the skinning rate.

3. The method as claimed in claim 2, wherein in the step 1), the crusted cake is prepared from the following raw materials in percentage by mass: 50% of cement raw material, CaSO₄20％，Na₂SO₄10% and KCl 20%; the raw materials are mixed and then kept for 2-5 min under the pressure of 3-10 MPa, and more preferably kept for 3min under the pressure of 6 MPa.

4. A method according to claim 2 or 3, characterized in that in step 1), the diameter of the crusted cake is 20-50 mm, preferably 30 mm; and/or the mass of the crusting cake is 30-60 g, preferably 50 g.

5. The method according to claim 4, wherein in step 1), the sample size of the refractory material is 100mm x 30 mm; and/or drying the high-temperature-resistant material sample before weighing.

6. The method according to claim 5, wherein in step 2), the crust cake is placed on a central portion of the surface of the refractory material sample; preferably, the high temperature resistant material sample is placed on the surface central part of one side of 100mm multiplied by 100 mm.

7. The method according to any one of claims 2 to 6, wherein in step 2), the firing conditions are: the temperature is quickly recorded according to the temperature rise of 5 ℃/min, the temperature is heated to 1100 ℃, and the temperature is kept for 3 h.

8. The method according to claims 2-7, characterized in that in step 3) compressed air is blown at a pressure of 300 to 800kPa, preferably 500 kPa; and/or the diameter of the outlet of the nozzle is 2.36-2.44 mm.

9. The method according to claim 8, wherein in step 3), the distance between the nozzle and the combined part of the crust cake and the refractory material is 30-50 mm, preferably 40 mm; the included angle between the blowing direction of the nozzle and the high-temperature resistant material sample is 30-60 degrees, and preferably 45 degrees.

10. The method according to claim 9, characterized in that in step 3), blowing is performed along the circumference of the crust cake for 3-8 min, preferably 4 min.

Technical Field

The invention relates to the technical field of high-temperature resistant material evaluation, in particular to a method for evaluating the anti-skinning performance of a high-temperature resistant material for a cement kiln.

Background

High-temperature resistant materials at the high-temperature section of the suspension preheater, the precalciner and the smoke chamber of the rotary cement kiln are easy to crust, and the normal operation of the rotary cement kiln is influenced.

The currently adopted anti-skinning detection method is appendix A of an anti-skinning refractory castable anti-skinning test method in Black metallurgy industry Standard YB/T4193-2009 anti-skinning refractory castable. The method judges the anti-skinning performance of the refractory castable by judging the inclination angle of the calcined cake after inclination and the falling-off of the refractory castable, can only carry out qualitative judgment, cannot carry out quantitative comparison, and cannot well evaluate the anti-skinning performance of the high-temperature resistant material.

Disclosure of Invention

In order to accurately and quantitatively evaluate the anti-skinning performance of the high-temperature resistant material and overcome human and environmental interference factors in the evaluation process of the anti-skinning performance of the high-temperature resistant material, the invention provides a detection method of the anti-skinning performance of the high-temperature resistant material.

The invention provides a method for evaluating the anti-skinning performance of a high-temperature resistant material for a cement kiln, which comprises the steps of placing a skinning material cake on the surface of a high-temperature resistant material sample, and sintering at a high temperature to obtain an anti-skinning sample; and then, blowing the anti-skinning sample by adopting compressed gas, weighing the rest anti-skinning sample, and then evaluating the anti-skinning performance of the high-temperature resistant material.

According to some preferred embodiments of the invention, the method comprises the steps of:

step 1), preparing a high-temperature resistant material sample and a crusted cake: providing a high-temperature-resistant material sample and a crusting cake, and weighing the high-temperature-resistant material sample and the crusting cake:

step 2), sintering an anti-skinning sample: placing the crusting material cake on the surface of the high-temperature-resistant material sample, and sintering at high temperature to obtain an anti-crusting sample;

step 3), anti-skinning sample injection treatment: blowing the anti-skinning sample in the step 2) by using compressed gas, and weighing the rest anti-skinning sample;

and 4), evaluating the anti-skinning performance of the high-temperature resistant material according to the following formula:

in the formula, m₁Is the mass of the refractory material sample, m₂M is the mass of the crust cake₃The mass of the remaining anti-skinning sample is and J is the skinning rate.

According to some preferred embodiments of the present invention, in step 1), the crusted cake is prepared from the following raw materials in percentage by mass: 50% of cement raw material, CaSO₄ 20％，Na₂SO₄10% and KCl 20%; will be provided withAfter the raw materials are mixed, the raw materials are preferably kept for 2-5 min under the pressure of 3-10 MPa, and more preferably kept for 3min under the pressure of 6 MPa.

According to some preferred embodiments of the present invention, in step 1), the diameter of the crusted cake is 20-50 mm, preferably 30 mm; and/or the mass of the crusting cake is 30-60 g, preferably 50 g.

According to some preferred embodiments of the present invention, in step 1), the size of the refractory material sample is 100mm × 100mm × 30 mm; and/or drying the high-temperature-resistant material sample before weighing.

According to some preferred embodiments of the present invention, in the step 2), the skinned cake is placed on a surface center portion of the refractory material sample; preferably, the high temperature resistant material sample is placed on the surface central part of one side of 100mm multiplied by 100 mm.

According to some preferred embodiments of the invention, in step 2), the firing conditions are: the temperature is quickly recorded according to the temperature rise of 5 ℃/min, the temperature is heated to 1100 ℃, and the temperature is kept for 3 h.

According to some preferred embodiments of the invention, in step 3), compressed air at a pressure of 300 to 800kPa, preferably 500kPa, is blown; and/or the diameter of the outlet of the nozzle is 2.36-2.44 mm.

According to some preferred embodiments of the present invention, in the step 3), the distance between the nozzle and the combined part of the crust cake and the high temperature resistant material is 30-50 mm, preferably 40 mm; the included angle between the blowing direction of the nozzle and the high-temperature resistant material sample is 30-60 degrees, and preferably 45 degrees.

According to some preferred embodiments of the invention, in step 3), blowing is performed along the circumference of the crusted cake, and the blowing time is 3-8 min, preferably 4 min.

The invention has the beneficial effects that: according to the method for evaluating the anti-skinning performance of the high-temperature resistant material for the cement kiln, the skinning cake is blown under the rated pressure by compressed air, so that the skinning cake which is not adhered to the high-temperature resistant material is peeled, the influence of human and environmental factors is eliminated, the anti-skinning evaluation quantification is realized by detecting the quality change, and the method has the advantages of high repeatability, small influence of the environmental factors, simplicity in operation and capability of well evaluating the anti-skinning performance of the high-temperature resistant material.

Drawings

Fig. 1 is a schematic view of the refractory material (size) according to an embodiment of the present invention.

FIG. 2 is a schematic view of the position of the crust cake on the surface of the refractory material according to the embodiment of the present invention.

FIG. 3 is a schematic view of a compressed air blown crusted cake according to an embodiment of the present invention.

In the figure, 1 is a compressed air nozzle; 2 is a crusted material cake; 3 is a high temperature resistant material.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

The examples of the present invention do not include specific techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specification. The instruments, reagents and the like used are conventional products which are not known to manufacturers and can be purchased from regular distributors. The raw materials used in the invention can be conveniently bought in domestic product markets.

Some preferred embodiments of the invention provide a method for evaluating the anti-skinning performance of a high-temperature resistant material for a cement kiln, which comprises the following specific steps and parameters:

1. preparation of high temperature resistant material sample

The size of the high-temperature resistant material sample is 100mm multiplied by 30mm, and the surface of the high-temperature resistant material is flat; when the high-temperature resistant material sample is an unfired product (an unshaped high-temperature resistant material), preserving the heat at 800 ℃ for 1h and then naturally cooling for later use; when the material is a sintered product (a shaped high-temperature-resistant material), the material is cooled for standby after heat preservation at 110 ℃ for 24 hours.

2. Crust material preparation

The crusting cake weighs 50g and comprises the following components: 50% of cement raw material, CaSO₄ 20％，Na₂SO₄10 percent of KCl and 20 percent of cement raw materials, wherein the kiln materials are taken from the bottommost part of a preheater. And uniformly mixing the crusting material raw materials, and maintaining the pressure for 3min by using a powder tablet press under the pressure of 6MPa to prepare a crusting cake with the diameter of 30 mm.

3. Anti-skinning test sample experiment for high temperature resistant material

Weighing the mass m of a sample of a refractory material₁Weighing the mass m of the crusted material cake₂The crusting cake is placed at the central part of the surface of the high-temperature resistant material (100mm multiplied by 100mm side), is put into a high-temperature electric furnace, is heated to 1100 ℃ at the heating rate of 5 ℃/min, is kept at 1100 ℃ for 3h, and is naturally cooled.

4. Non-bonded skinning material removal

Standing the sample prepared by heat preservation at 1100 deg.C for 3h, and directly measuring the mass m of the high temperature resistant material if the crust material cake directly falls off and is not bonded₃Or after blowing, if the crusted cake is adhered to the high-temperature resistant material, the joint of the cake and the high-temperature resistant material is blown by compressed air with the pressure of 500kPa, and the diameter of the outlet of the nozzle is 2.36-2.44 mm. The distance between the nozzle and the combined part of the material cake and the high-temperature resistant material is 40mm, the included angle between the nozzle and the high-temperature resistant material is 45 degrees, the mass m of the high-temperature resistant material is measured after the high-temperature resistant material is sprayed for 4min along the circumference of the material cake at a constant speed₃。

5. Evaluation of high temperature resistant Material anti-skinning Property

Wherein J is the crust rate.

Example 1

1. Preparation of high temperature resistant material sample

Adopting an unshaped high-temperature resistant material, adding water according to the processing specification of the high-temperature resistant material, stirring, placing into a mold with the size of 100mm multiplied by 30mm, vibrating for molding, hardening, demolding, and then placing into a drying oven to dry for 24 hours at 110 ℃. The dried sample is sintered for 1h at 800 ℃ in an electric furnace to remove chemical water in the sample, and the mass m of the sample is measured₁Was 674 g. The dimensions of the refractory material samples are shown in figure 1.

2. Crust material cake preparation

The leather material is 50g, and the leather material comprises the following components: 50% of cement raw material, CaSO₄ 20％，Na₂SO₄ 10％，KCl 20％，

Obtaining cement raw material from actual use site of cement plantThe raw materials are dried in an oven at 110 ℃ for 24 hours. Weighing 25g of cement raw material and 10g of CaSO₄、5g Na₂SO₄And 10g of KCl, and placing the mixture into a corundum mortar, mixing for 10min, and then placing the mixture into a steel mold with the inner diameter of 30 mm. Pressing the crust material in the die into a cake by a powder tablet press, keeping the pressure at 6MPa for 3min, and measuring the mass m of the cake after demolding₂Was 50 g.

3. Anti-skinning sample firing

The crusting cake was placed in the middle of the surface (100 mm. times.100 mm) of the refractory (see FIG. 2), and the placed sample was placed flat in an electric furnace. The temperature of the electric furnace is raised to 1100 ℃ at the heating rate of 5 ℃/min, the temperature is preserved for 3h, and the sample is naturally cooled.

4. Anti-skinning sample blowing treatment

The naturally cooled anti-skinning sample was fixed with 30mm × 100mm as the bottom surface, and the anti-skinning sample was blown with compressed air at a pressure of 500 kPa. The diameter of the nozzle outlet is 2.36-2.44mm, and the compressed air nozzle 1 is 40mm away from the sample (the junction of the crust cake 2 and the refractory 3) and makes an angle of 45 degrees with the surface plane of the refractory (100mm x 100mm) (as shown in figure 3). Nozzles (compressed air nozzles) blown the crust cake circumferentially for 4min to ensure that all parts of the cake were completely blown through by the compressed air. Measuring mass m of the sample after blowing₃681 g.

5. Evaluation of anti-skinning Properties

Wherein J represents the skinning rate, and the smaller the J value is, the better the anti-skinning effect of the high-temperature resistant material is.

Example 2

The method and the skinning material used in the same example 1 were adopted, except that the formed refractory material was cut into rectangular samples of 100mm × 100mm × 30mm by a cutter, the rectangular samples were dried in a drying oven at 110 ℃ for 24 hours, and the mass m of the dried samples was measured₁692 g. Crust material weight m₂Was 50 g. After treatment, m₃Is 694 g. Then

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.