1. A preparation method of high-density periclase-forsterite composite refractory ceramic is characterized by comprising the following steps: magnesite tailings and polycrystalline silicon cutting waste are used as raw materials, are uniformly mixed after being pretreated, and are cooled along with a furnace after being formed, dried and sintered at high temperature.

2. The preparation method according to claim 1, comprising the following steps:

(1) pretreatment of raw materials: preprocessing magnesite tailings and polycrystalline silicon cutting waste respectively;

(2) mixing materials: mixing the pretreated magnesite tailings and the polycrystalline silicon cutting waste, and performing ball milling to form uniformly mixed raw materials;

(3) molding: adding a binder into the uniformly mixed raw materials in the step (2), and pressing a green body;

(4) and (3) drying: drying the pressed and formed green body;

(5) and (3) high-temperature sintering: and sintering the dried green body at 1250-1650 ℃, preserving heat for 2-4 h, and cooling along with the furnace to obtain the final product.

3. The preparation method according to claim 2, wherein the step (1) pretreatment process is: crushing and sieving magnesite tailings; calcining the polycrystalline silicon cutting waste for 2-4 hours at 400-600 ℃.

4. The preparation method according to claim 2, wherein the step (2) is carried out by mixing magnesite tailings and crystalline silicon cutting waste materials in a mass ratio of (85-95) to (5-15).

5. The method according to claim 2, wherein the binder used in step (3) is added in an amount of 2 to 5 wt% based on the raw material.

6. The preparation method of claim 5, wherein the binder is one or more of polyvinyl alcohol, liquid phenolic resin and water glass.

7. The preparation method according to claim 2, wherein the drying temperature in the step (4) is 100-120 ℃, and the drying time is 20-30 h.

8. The production method according to claim 1, wherein the temperature rise rate in the step (5) is 1 to 3 ℃/min within 900 ℃ and 5 to 10 ℃/min within 900 to 1650 ℃.

9. The high-density periclase-forsterite composite refractory ceramic prepared by the preparation method as claimed in any one of claims 1 to 8.

Background

Periclase has the advantages of high melting point (2800 ℃), large raw ore storage capacity and the like, but has large lattice energy, is difficult to sinter, and has poor thermal shock resistance due to large linear expansion coefficient. The forsterite has the advantages of small linear expansion coefficient, low heat conduction, good slag resistance and the like, but the forsterite has the problems of high impurity content, high porosity and the like, so that the refractoriness is low.

Periclase and forsterite are generally produced by sintering or electrically melting natural minerals such as magnesite, silica ore, talc ore, etc. Compared with the prior art, the sintering method has low density of products prepared at low treatment temperature (1450-1900 ℃), but has low cost; the product prepared by the electric melting method has good crystallinity and higher cost, and the treatment temperature is higher (more than 2800 ℃). Under the background of 'carbon peak reaching' and 'carbon neutralization', the sintering method with lower energy consumption is undoubtedly more promising, so how to improve the comprehensive performance of products prepared by the sintering method is a research difficulty to be solved urgently. The current common solution is to firstly lightly burn the raw materials at a lower temperature for one time and then re-burn the raw materials at a target temperature to obtain the final product. Although the performances such as the density and the like of the product can be improved to a certain extent through twice calcination, the cost is correspondingly increased along with the increase of the working procedures, and the extra energy consumption is increased through twice calcination.

On the other hand, with the development of extensive type in recent years, the price of high-grade ore is high due to continuous poor mining and excellent mining, and meanwhile, a large amount of tailings in a mining area are accumulated like a mountain, so that a serious environmental problem is caused. Therefore, if the tailings can be reasonably utilized again, the method has important significance for reducing the cost of the magnesia refractory materials including periclase-forsterite and relieving the pressure of the corresponding industry.

Disclosure of Invention

The invention aims to solve the problems in the prior art, aims to improve the comprehensive performance of the periclase-forsterite composite refractory ceramic material on the basis of reducing the preparation cost of the periclase-forsterite composite refractory ceramic material, and particularly provides a low-cost high-density periclase-forsterite composite refractory ceramic and a preparation method thereof. The invention prepares the periclase-forsterite composite refractory ceramic material with excellent comprehensive performance by taking reverse flotation magnesite tailings as a raw material, taking polycrystalline silicon cutting waste as a supplementary silicon source and adopting a solid-phase reaction method in a pre-prepared proportion.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a preparation method of high-density periclase-forsterite composite refractory ceramic, which comprises the following steps: magnesite tailings and polycrystalline silicon cutting waste are used as raw materials, are uniformly mixed after being pretreated, and are cooled along with a furnace after being formed, dried and sintered at high temperature.

Preferably, the preparation method specifically comprises the following steps:

(1) pretreatment of raw materials: preprocessing magnesite tailings and polycrystalline silicon cutting waste respectively;

(2) mixing materials: mixing the pretreated magnesite tailings and the polycrystalline silicon cutting waste, and performing ball milling to form uniformly mixed raw materials;

(3) molding: adding a binder into the uniformly mixed raw materials in the step (2), and pressing a green body;

(4) and (3) drying: drying the pressed and formed green body;

(5) and (3) high-temperature sintering: and sintering the dried green body at 1250-1650 ℃, preserving heat for 2-4 h, and cooling along with the furnace to obtain the final product.

Preferably, the step (1) pretreatment process is as follows: crushing and sieving magnesite tailings; and calcining the polycrystalline silicon cutting waste for 2-4 hours at 400-600 ℃, wherein the aim of calcining is to remove polyethylene glycol and water in the polycrystalline silicon cutting waste.

Preferably, the magnesite tailings in the step (1) are high-silicon tailings produced by a reverse separation process, and the magnesite tailings have chemical compositions of 40 wt% -45 wt% of MgO and SiO₂4-8 wt% and the loss on ignition is 47-50%.

Preferably, the polycrystalline silicon cutting waste in the step (1) is waste generated by a silicon carbide slurry cutting method, and the chemical composition of Si is 45 wt% -55 wt%, and SiC is 42 wt% -52 wt%.

Preferably, the magnesite tailings and the crystalline silicon cutting waste are mixed according to the mass ratio of (85-95) to (5-15) in the step (2). The proportion of the raw materials directly influences the final phase proportion in the sample, and on one hand, the phase proportion influences various properties of the material; on the other hand, the phase transformation process is accompanied by volume expansion effect, and if the degree of expansion cannot be well controlled, secondary defects are easily formed in the sample due to excessive volume expansion.

Preferably, the ball milling medium in the ball milling process in the step (2) is ethanol, the ball milling rotating speed is 200-300 r/min, and the ball milling time is 5-10 h.

Preferably, the addition amount of the binder in the step (3) is 2 to 5 weight percent of the raw material. The molding pressure in the step (3) is 50 to 200 MPa.

Preferably, the binder is one or a combination of polyvinyl alcohol, liquid phenolic resin and water glass.

Preferably, the drying temperature in the step (4) is 100-120 ℃, and the drying time is 20-30 h.

Preferably, the heating rate in the step (5) is 1-3 ℃/min within 900 ℃, and 5-10 ℃/min within 900-1650 ℃. The temperature rise rate mainly affects the decomposition process of magnesium carbonate in the raw materials, and if the temperature rise rate is too fast, the decomposition is too fast, and a large amount of generated gas can cause defects such as sample surface cracking and the like. The sintering temperature is the most important factor directly influencing the overall sintering effect and performance of the sample. The temperature is too low, the sample is not sintered sufficiently, the green body is not compact enough, and the performance is poor. The temperature is too high, on one hand, energy consumption is wasted, and the cost is increased; on the other hand, over-firing phenomena such as excessive grain growth and partial performance deterioration can also occur.

The invention also provides the high-density periclase-forsterite composite refractory ceramic prepared by the preparation method.

The invention discloses the following technical effects:

the magnesite tailings and the polycrystalline silicon cutting waste which are used as raw materials for preparing the high-density periclase-forsterite composite refractory ceramic have obvious advantages compared with conventionally selected magnesite, silica, quartz powder and other industrial raw materials, so that the high raw material cost is saved, and the environmental pressure caused by the accumulation of the tailings and the waste is relieved. In addition, a brand new idea of 'supplementing wastes with wastes' is provided, crystalline silicon cutting wastes are firstly used as a supplementary silicon source to be introduced into the preparation process of forsterite, and the method is beneficial toThe unique occurrence state of Si in the waste material can generate beneficial promotion to the sintering process of the material, and the prepared product has higher densification degree and better comprehensive performance. The performance indexes of the periclase-forsterite refractory material prepared by the invention are as follows: the apparent porosity is 0.69-3.18%, and the volume density is 3.12-3.35 g/cm^-3The relative density is 93.72-96.31%, the normal-temperature compressive strength is 351-656 MPa, the normal-temperature flexural strength is 39-73 MPa, and the residual strength retention rate after two times of air cooling at 1100 ℃ is 86-92%.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is an SEM image of a high-density periclase-forsterite composite refractory ceramic prepared in example 1;

FIG. 2 is an XRD pattern of the high-denseness periclase-forsterite composite refractory ceramic prepared in example 1;

FIG. 3 is an SEM photograph of a highly densified periclase-forsterite composite refractory ceramic prepared in example 2.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

In the embodiment of the invention, the magnesite tailings are high-silicon tailings produced by a reverse separation process, and the magnesite tailings comprise 40-45 wt% of MgO and SiO₂4-8 wt% and the loss on ignition is 47-50%.

In the embodiment of the invention, the polycrystalline silicon cutting waste is waste generated by a silicon carbide slurry cutting method, and the chemical components of the polycrystalline silicon cutting waste are 45-55 wt% of Si and 42-52 wt% of SiC.

The detection standard of the low-cost high-density periclase-forsterite composite refractory ceramic material prepared by the invention is as follows: according to the corresponding national standard: measuring the volume density, apparent porosity and true porosity of the compact and shaped refractory product according to GB/T2997-2015; according to GB/T5072-2008, the normal-temperature compressive strength of the refractory material is measured; testing the normal-temperature rupture strength method of the refractory material according to GB/T3001-2017; the thermal shock resistance of the refractory material is tested according to GB/T30873-.

Example 1

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder, and calcining the polycrystalline silicon cutting waste at 500 ℃ for 2 hours to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of magnesite tailings to crystalline silicon cutting waste of 95: 5, and then ball-milling for 5 hours in a high-energy planetary ball mill at the rotating speed of 300r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 5 wt% of polyvinyl alcohol binder into the raw materials which are subjected to uniform ball milling, and pressing the raw materials into green bodies under the pressure of 100 MPa;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln at 120 ℃ for 24 hours;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1400 ℃ in a high-temperature furnace according to different batches, keeping the temperature for 3h, wherein the heating rate within 900 ℃ is 2 ℃/min, the heating rate within 1400 ℃ is 5 ℃/min, and cooling along with the furnace to obtain the final product.

The SEM diagram and XRD diagram of the high-density periclase-forsterite composite refractory ceramic material prepared in the embodiment are shown in the figure 1 and 2 respectively. Through detection, the high-density periclase-forsterite composite refractory ceramic material prepared in the embodiment has the following performance indexes: MgO content 71.5%, Mg₂SiO₄The content is 28.5%, the apparent porosity is 2.12%, and the bulk density is 3.19g/cm^-3The relative density is 94.67%, the normal-temperature compressive strength is 479MPa, the normal-temperature flexural strength is 43MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 87%.

Example 2

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, and sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder; calcining the polycrystalline silicon cutting waste at 500 ℃ for 2h to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of magnesite tailings to crystalline silicon cutting waste of 90: 10, and then ball-milling for 5 hours in a high-energy planetary ball mill at the rotating speed of 300r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 5 wt% of polyvinyl alcohol binder into the raw materials which are subjected to uniform ball milling, and pressing the raw materials into green bodies under the pressure of 100 MPa;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln at 120 ℃ for 24 hours;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1300 ℃ in a high-temperature furnace according to different batches, keeping the temperature for 3h, wherein the heating rate within 900 ℃ is 3 ℃/min, the heating rate within 1300 ℃ is 7 ℃/min, and cooling along with the furnace to obtain the final product.

An SEM image of the high-density periclase-forsterite composite refractory ceramic material prepared in the example is shown in FIG. 3. Through detection, the performance indexes of the magnesium stone-forsterite composite refractory material prepared by the embodiment are as follows: MgO content 52.6%, Mg₂SiO₄47.4 percent of the content, 1.88 percent of apparent porosity and 3.21g/cm of volume density^-3The relative density is 94.87%, the normal-temperature compressive strength is 567MPa, the normal-temperature flexural strength is 52MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 89%.

Example 3

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, and sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder; calcining the polycrystalline silicon cutting waste at 600 ℃ for 2h to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of magnesite tailings to crystalline silicon cutting waste of 95: 5, and then ball-milling the raw materials for 10 hours in a high-energy planetary ball mill at the rotating speed of 200r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 5 wt% of liquid phenolic resin binder into the raw materials which are subjected to uniform ball milling, and pressing the raw materials into green bodies under the pressure of 50 MPa;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln for 30 hours at 100 ℃;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1250 ℃ in a high-temperature furnace according to different batches, preserving heat for 2h, wherein the heating rate within 900 ℃ is 1 ℃/min, the heating rate within 1250 ℃ is 7 ℃/min, and cooling along with the furnace to obtain the final product.

Through detection, the performance indexes of the magnesium stone-forsterite composite refractory ceramic material prepared by the embodiment are as follows: MgO content 72.2%, Mg₂SiO₄The content is 27.8%, the apparent porosity is 3.18%, and the bulk density is 3.27g/cm^-3The relative density is 93.72%, the normal-temperature compressive strength is 351MPa, the normal-temperature flexural strength is 39MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 86%.

Example 4

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, and sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder; calcining the polycrystalline silicon cutting waste at 400 ℃ for 4h to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of the magnesite tailings to the crystalline silicon cutting waste of 85: 15, and then ball-milling the raw materials for 8 hours in a high-energy planetary ball mill at the rotating speed of 250r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 2 wt% of water glass binder into the raw materials which are subjected to uniform ball milling, and pressing under 150MPa to prepare green bodies;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln at 120 ℃ for 20 hours;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1450 ℃ in a high-temperature furnace according to different batches, keeping the temperature for 4h, wherein the heating rate within 900 ℃ is 3 ℃/min, the heating rate within 1450 ℃ is 10 ℃/min, and cooling along with the furnace to obtain the final product.

Through detection, the performance indexes of the magnesium stone-forsterite composite refractory material prepared by the embodiment are as follows: MgO content of 30.3%, Mg₂SiO₄The content is 69.7%, the apparent porosity is 1.25%, and the bulk density is 3.12g/cm^-3The relative density is 95.36%, the normal-temperature compressive strength is 558MPa, the normal-temperature flexural strength is 65MPa, and the retention rate of the residual strength after two air-cooling at 1100 ℃ is 92%.

Example 5

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, and sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder; calcining the polycrystalline silicon cutting waste at 500 ℃ for 4h to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of the magnesite tailings to the crystalline silicon cutting waste of 85: 15, and then ball-milling the raw materials for 8 hours in a high-energy planetary ball mill at the rotating speed of 250r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 3 wt% of polyvinyl alcohol binder into the raw materials which are subjected to uniform ball milling, and pressing the raw materials into green bodies under the pressure of 200 MPa;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln at 120 ℃ for 25 hours;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1550 ℃ in a high-temperature furnace according to different batches, keeping the temperature for 4h, wherein the heating rate within 900 ℃ is 2 ℃/min, the heating rate within 1550 ℃ is 8 ℃/min, and cooling along with the furnace to obtain the final product.

Through detection, the performance indexes of the magnesium stone-forsterite composite refractory ceramic material prepared by the embodiment are as follows: MgO content of 30.9%, Mg₂SiO₄The content is 69.1%, the apparent porosity is 0.69%, and the bulk density is 3.22g/cm^-3Relative density of96.31 percent, the normal-temperature compressive strength is 656MPa, the normal-temperature flexural strength is 73MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 91 percent.

Example 6

A preparation method of a low-cost high-density periclase-forsterite composite refractory ceramic material comprises the following specific operation steps:

(1) pretreatment of raw materials: fully crushing magnesite tailings, and sieving the crushed magnesite tailings with a 200-mesh sieve to obtain fine powder; calcining the polycrystalline silicon cutting waste at 600 ℃ for 2h to remove polyethylene glycol and water;

(2) mixing materials: weighing the processed raw materials according to the mass ratio of magnesite tailings to crystalline silicon cutting waste of 90: 10, and then ball-milling the raw materials for 8 hours in a high-energy planetary ball mill at the rotating speed of 200r/min by using ethanol as a ball-milling medium to form uniformly mixed raw materials;

(3) molding: respectively adding 5 wt% of water glass binder into the raw materials which are subjected to uniform ball milling, and pressing the raw materials into green bodies under the pressure of 200 MPa;

(4) and (3) drying: fully drying the pressed and formed green bodies in batches in a hot air drying box or a tunnel drying kiln at 120 ℃ for 30 hours;

(5) and (3) high-temperature sintering: and heating the dried green bodies to 1650 ℃ in a high-temperature furnace according to different batches, keeping the temperature for 3h, wherein the heating rate within 900 ℃ is 3 ℃/min, the heating rate within 1650 ℃ is 10 ℃/min, and cooling along with the furnace to obtain the final product.

Through detection, the performance indexes of the magnesium stone-forsterite composite refractory material prepared by the embodiment are as follows: MgO content 51.2%, Mg₂SiO₄The content is 48.8%, the apparent porosity is 1.78%, and the bulk density is 3.35g/cm^-3The relative density is 95.82%, the normal-temperature compressive strength is 596MPa, the normal-temperature flexural strength is 69MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 87%.

Comparative example 1

The difference from example 2 is only that in step (5), the temperature rise rate is 6 ℃/min at 900 ℃ or lower and 20 ℃/min at 1300 ℃ or lower.

Through detection, the high-density periclase-forsterite composite refractory ceramic material prepared by the comparative exampleThe performance indexes of the material are as follows: MgO content 52.1%, Mg₂SiO₄47.9 percent of the total content, 6.24 percent of apparent porosity and 3.04g/cm of volume density^-3The relative density is 89.24%, the normal-temperature compressive strength is 318MPa, the normal-temperature flexural strength is 26MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 88%.

Comparative example 2

The only difference from example 2 is that the temperature increase rate in step (5) was 2 ℃/min.

Through detection, the high-density periclase-forsterite composite refractory ceramic material prepared by the comparative example has the following performance indexes: MgO content 52.3%, Mg₂SiO₄47.7 percent of the total content, 2.18 percent of apparent porosity and 3.14g/cm of volume density^-3The relative density is 92.15%, the normal-temperature compressive strength is 502MPa, the normal-temperature flexural strength is 45MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 86%.

Comparative example 3

The difference is the same as the example 2, only in that the step (2) is weighed according to the mass ratio of the magnesite tailings to the crystalline silicon cutting waste material of 1: 1.

Through detection, the high-density periclase-forsterite composite refractory ceramic material prepared by the comparative example has the following performance indexes: MgO content 52.7%, Mg₂SiO₄47.3 percent of the total content, 4.85 percent of apparent porosity and 3.08g/cm of volume density^-3The relative density is 90.38%, the normal-temperature compressive strength is 437MPa, the normal-temperature flexural strength is 32MPa, and the residual strength retention rate after two air-cooling at 1100 ℃ is 88%.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.