Scraping device and coal slagging property test method

Abstract

The invention relates to the technical field of image enhancement, in particular to a scraping device and a coal slagging property test method.The scraping device comprises an operation assembly which comprises a base, a moving part arranged at the center axis position of the top of the base, a support arranged at the top of the base and a slag scraping tool arranged at the bottom of the support; and the sensors are arranged on the moving part and the slag scraping cutter. The method has the beneficial effects that the slag-bonding property of the coal type is evaluated according to the acting force of the slag scraping cutter and the displacement of the slag scraping cutter relative to the slag rod clamping groove, the judgment influence caused by human subjectivity is effectively avoided, and the method has important significance on safe combustion selection of the coal type, particularly selection of a high-sodium coal blending combustion proportion, and has the characteristics of quick and accurate test and high efficiency. And the method can be widely applied to coal-fired power plants.

Description

Technical Field

[0001] The invention relates to the technical field of coal slagging property testing, in particular to a scraping device and a method for testing the slagging property of chemical coal. Background Art

[0002] As the main characteristic parameter of coal combustion, the slagging characteristics of coal types play a vital reference role in boiler selection, transformation and safe operation. With the continuous enrichment of domestic power coal, the accurate judgment of its slagging characteristics directly affects the safety and economy of the unit. However, in the calculation process of the slagging index of ash slag, it is necessary to assign a quantitative value to the slagging source. This step is based on human subjective experience, which may lead to a maximum error of 100%. Different slag grades only represent relative degrees, which is relatively rough. The difference gradient and the equivalent relationship between slag grade and slag type assignment cannot be determined. More and more power coals have serious slagging problems. The slag type is the same as molten, so the slag type assignment is the same when judging, and the slag source cannot be judged more accurately. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a scraping device and a test method for the slagging property of coal, which can solve the problems mentioned in the background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] The present invention provides a scraping device, comprising an operating assembly, including a base, a moving part arranged at the central axis position of the top of the base, a bracket arranged at the top of the base, a scraping tool arranged at the bottom of the bracket, and sensors arranged on the moving part and the scraping tool.

[0008] As a preferred solution of the scraping device of the present invention, the moving part includes a progressive motor arranged on the top of the base, one end of the progressive motor is connected to a screw rod through an output shaft, a slider is slidably installed on the screw rod, the other end of the screw rod is embedded in a fixed plate, the fixed plate is welded to one end of the top of the base, a slag rod groove is provided on the top of the slider, the slider is slidably installed inside a slide rail, and the slide rail is opened on the top of the base.

[0009] As a preferred solution of the scraping device of the present invention, the sensor includes a pressure sensor and a displacement sensor.

[0010] As a preferred solution of the scraping device of the present invention, wherein: the pressure sensor is arranged between the scraping tool and the bracket; the displacement sensor is arranged on the fixed plate.

[0011] In order to solve the above technical problems, the present invention also provides the following technical solutions: a method for testing the slagging property of chemical coal, comprising collecting target data in real time through a target device and evaluating the slagging property of the coal;

[0012] The work W done by the ash stripping process during the target data scraping is calculated by using integral operation;

[0013] The slagging index Sm is calculated based on the slagging properties combined with other parameters.

[0014] As a preferred solution of the method for testing the slagging properties of chemical coal species of the present invention, the target device includes a pressure sensor and a displacement sensor.

[0015] As a preferred solution of the method for testing the slagging property of chemical coal of the present invention, the target data includes the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod slot.

[0016] As a preferred embodiment of the method for testing the slagging property of chemical coal of the present invention, the target data is collected in real time by the target device, including:

[0017] The pressure sensor and the displacement sensor are used to respectively collect the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod slot in real time.

[0018] As a preferred embodiment of the method for testing the slagging properties of chemical coal species of the present invention, the other parameters include the slag type assignment Scm, the characterization temperature θ and the calorific value correction coefficient ζ.

[0019] As a preferred embodiment of the method for testing the slagging properties of chemical coal species of the present invention, the slag type assignment Scm includes five levels: molten, viscous, strongly cohesive, cohesive, and weakly cohesive.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the slagging property of the coal type is evaluated according to the force of the scraper tool and the displacement of the scraper tool relative to the slag rod slot, which effectively avoids the influence of human subjectivity on judgment, and is of great significance for the safe combustion selection of coal types, especially the selection of the blending ratio of high-sodium coal. The test is fast and accurate, with an accuracy rate of more than 85%, and can be widely used in coal-fired power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0022] Figure 1 It is a schematic diagram of the overall structure of the scraping device.

[0023] Figure 2 This is a working principle diagram of the scraping device.

[0024] Figure 3 Flow chart of the method for testing the slagging properties of chemical coal. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0028] Example 1

[0029] Reference Figure 1-2 , which is the first embodiment of the present invention, provides a scraping device,

[0030] It includes an operating assembly 100, including a base 101, a moving part 102 arranged at the central axis position of the top of the base 101, and the setting of the moving part 102 is convenient for driving the coal slag on the slag rod slot e to contact the slag scraping tool 104, and a bracket 103 arranged on the top of the base 101. The bracket 103 is a door-shaped bracket, and a telescopic structure is arranged inside. Through the setting of the telescopic structure, the bracket 103 can be lifted upward when the bottom scraping tool 104 is replaced, so that the staff can better replace the scraping tool 104. After the scraping tool 104 is replaced, it can be retracted downward to drive the scraping tool 1 04 moves downward synchronously, so that the scraper tool 104 can better contact the coal slag on the slag rod slot 102e. The scraper tool 104 arranged at the bottom of the bracket 103 can effectively and completely peel off the ash on the slag rod slot 102e and the bottom of the slag rod slot 102e through the setting of the scraper tool 104. The sensor 105 arranged on the moving part 102 and the scraper tool 104 can detect the force of the scraper tool 104 and the displacement of the scraper tool 104 relative to the slag rod slot 102e during the stripping process.

[0031] Preferably, the moving member 102 includes a progressive motor 102a arranged on the top of the base 101, one end of the progressive motor 102a is connected to a screw rod 102b through an output shaft, and a slider 102c is slidably installed on the screw rod 102b. When the screw rod 102b rotates under the rotation of the progressive motor 102a, the slider 102c slides left and right on the screw rod 102b, and the other end of the screw rod 102b is embedded in a fixed plate 102d, and the fixed plate 102d is welded to one end of the top of the base 101. A slag rod groove 102e is provided on the top of the slider 102c, and the slider 102c is slidably installed inside a slide rail 102f. The slide rail 102f is opened on the top of the base 101. Through the opening of the slide rail 102f, the slider 102c is effectively limited to ensure that the slider 102c will not be positionally offset while moving left and right horizontally when the screw rod 102b rotates.

[0032] Furthermore, the sensor 105 includes a pressure sensor 105a and a displacement sensor 105b. The pressure sensor 105a is arranged between the scraper tool 104 and the bracket 103; the displacement sensor 105b is arranged on the fixed plate 102d. Through the coordinated arrangement between the pressure sensor 105a and the displacement sensor 105b, the force of the scraper tool 104 and the displacement data of the scraper tool 104 relative to the slag rod slot 102e can be detected in real time during the ash stripping process, so as to facilitate the control system to better evaluate the slagging properties of the stripped ash.

[0033] When in use, first start the progressive motor 102a, and under the action of the progressive motor 102a, drive the screw rod 102b to rotate, and then drive the slider 102c on the screw rod 102b to move to a horizontal position, thereby driving the slag rod slot 102e on the top of the slider 102c to move horizontally synchronously, so that the slag on the slag rod slot 102e contacts the slag scraper tool 104, and the slag on the slag rod slot 102e can be smoothly detached from the slag rod slot 102e through the force of the scraper tool 104, and secondly, the force of the scraper tool 104 and the displacement data of the scraper tool 104 relative to the slag rod slot 102e are collected during the slag stripping process through the pressure sensor 105a and the displacement sensor 105b, and finally the slagging property of the slag is evaluated by calculation through the control system.

[0034] In summary, the beneficial effect of a method for testing the slagging property of chemical coal is to evaluate the slagging property of the coal according to the force of the scraper tool and the displacement of the scraper tool relative to the slag rod slot, effectively avoiding the influence of human subjectivity on judgment, which is of great significance for the safe combustion selection of coal, especially the selection of the blending ratio of high-sodium coal. It has the characteristics of fast and accurate testing with an accuracy rate of more than 85%, and can be widely used in coal-fired power plants.

[0035] Example 2

[0036] Reference Figure 3 , which is the second embodiment of the present invention, provides a method for testing the slagging property of a chemical coal, which comprises:

[0037] The target device collects the target data in real time and evaluates the slagging property of the coal;

[0038] The work W done by the ash stripping process during the target data scraping is calculated by using integral operation;

[0039] The slagging index Scm is calculated based on the slagging properties combined with other parameters.

[0040] It should be noted that, the speed of the slag rod clamping slot 2 is set to 1 cm / s, the displacement is 15 cm, and the slag index Scm is calculated as:

[0041] Scm=100ζNcm / (θ-1000)

[0042] Further, the target device includes a pressure sensor 105a and a displacement sensor 105b.

[0043] Furthermore, the target data includes the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod clamping groove.

[0044] Furthermore, the target data is collected in real time by the target device, including

[0045] The pressure sensor 105a and the displacement sensor 105b respectively collect the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod clamping groove in real time.

[0046] Furthermore, other parameters include slag type assignment Ncm, characterization temperature θ and calorific value correction coefficient ζ.

[0047] Furthermore, the slag type is assigned Ncm, including five levels: molten, viscous, strongly cohesive, cohesive, and weakly cohesive.

[0048] It should be noted that the slag type assignment Ncm is the ash slag deposited on the slagging source, which is divided into five levels from strong to weak according to its bonding tightness, namely, molten, sticky, strong cohesive, cohesive, and weak cohesive, and is assigned 0.25, 0.5, 1, 1.75, and 2 respectively;

[0049] The most serious slag characteristic value Ncm=Nmax+D

[0050] Common molten slag of boilers is divided into vitreous slag and non-vitreous slag according to its shape and severity: vitreous slag is distributed regularly on the slag rod at high temperature (1300℃), and is drop-shaped and has a glassy luster. The bottom of non-vitreous slag melts, and as the slag grows, non-vitreous slag adheres to the surface. In order to maintain consistency with the original standard, the basic strength value of vitreous slag is N1=3.0, the non-vitreous value is N2=2.5, and the basic values ​​of sticky slag and other slag types remain unchanged.

[0051] D represents the adhesion of ash to slag rod, thus ensuring that the value of Ncm has a good linear fit with the severity of ash. Through testing of different slag types, it is found that the value range of W, the work done by scraping ash, is usually 0-3.0 J, and its value is of the same order of magnitude as the slag type assignment (the slag type assignment itself has a certain linear relationship with the ash bonding strength). It is an effective way to distinguish between strong slag types and make Ncm have a good linear fit with the slag tendency, and the assignment D=W.

[0052] Further, characterizing the temperature θ includes,

[0053] When the ash melts, θ represents the initial melting temperature of the ash;

[0054] When there is no molten slag type, the value of θ remains unchanged.

[0055] It should be noted that in the test system, when the melting of ash is detected, a characteristic temperature (θ) needs to be determined. This temperature can be determined by measuring the lowest melting temperature (T0) of the ash in the molten slag rod slot. This means that in a series of temperature measurements, T0 is the lowest temperature value at which the ash begins to melt;

[0056] If no ash melting is observed during testing, the characterization temperature (θ) will remain unchanged. This may mean using a preset reference temperature or using other standard methods to determine this temperature.

[0057] Furthermore, the calorific value correction coefficient ζ includes a slagging index Scm corrected based on the theoretical combustion temperature of the coal.

[0058] It should be noted that ζ, as a correction of the theoretical combustion temperature of coal for the slagging index, takes into account the influence of the combustion characteristics of coal on the slagging property. When the combustion temperature in the furnace is higher than the ash melting point, the ash melts and the viscosity increases. A higher theoretical temperature means that the slagging temperature range of coal is wider and the slagging possibility is higher. Therefore, the slagging index Scm has the same change trend as the theoretical combustion temperature, and has an obvious positive linear correlation, ζ=f(t1).

[0059] In combustion science, the theoretical combustion temperature of coal indicates the highest temperature that the combustion products can reach when the chemical reactants in the coal are completely burned in an adiabatic system. The theoretical combustion temperature is:

[0060]

[0061] Among them, t1 is the theoretical combustion temperature of the fuel, Qd is the low-temperature calorific value of the fuel, Vn is the amount of combustion products generated, and C is the average volumetric specific heat of the combustion products from 0℃ to t.

[0062] Since the calculation of theoretical combustion temperature is complicated, the received base low calorific value Qnet,ar (in MJ / kg) in coal can be used instead of t1, that is, ζ=f(Qnet,ar). In order to ensure the order of magnitude of the Scm value, the coefficient ζ is taken as the ratio of the calorific value in coal to the average calorific value of high-sodium coal. The average calorific value of Xinjiang high-sodium coal calculated by the Thermal Engineering Institute's power coal database is Qnet,ar=21, so ζ=Qnet,ar / 21.

[0063] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A scraping device, characterized in that: include, An operating assembly (100) comprises a base (101), a moving member (102) arranged at a central axis position at the top of the base (101), a bracket (103) arranged at the top of the base (101), a scraping tool (104) arranged at the bottom of the bracket (103), and a sensor (105) arranged on the moving member (102) and the scraping tool (104).

2. The scraping device according to claim 1, characterized in that: The moving part (102) comprises a progressive motor (102a) arranged on the top of the base (101); one end of the progressive motor (102a) is connected to a screw rod (102b) via an output shaft; a slider (102c) is slidably mounted on the screw rod (102b); the other end of the screw rod (102b) is embedded in a fixed plate (102d); the fixed plate (102d) is welded to one end of the top of the base (101); a slag rod clamping groove (102e) is arranged on the top of the slider (102c); the slider (102c) is slidably mounted inside a slide rail (102f); and the slide rail (102f) is opened on the top of the base (101).

3. The scraping device according to claim 1, characterized in that: The sensor (105) includes a pressure sensor (105a) and a displacement sensor (105b).

4. The scraping device according to claim 3, characterized in that: The pressure sensor (105a) is arranged between the scraper tool (104) and the bracket (103); and the displacement sensor (105b) is arranged on the fixing plate (102d).

5. A method for testing the slagging properties of chemical coal, applied to the scraping device as claimed in any one of claims 1 to 3, characterized in that: include, The target device collects the target data in real time and evaluates the slagging property of the coal; The work W done by the ash stripping process during the target data scraping is calculated by using integral operation; The slagging index Scm is calculated based on the slagging properties combined with other parameters.

6. The method for testing the slagging property of chemical coal according to claim 5, characterized in that: The target device includes a pressure sensor (105a) and a displacement sensor (105b).

7. The method for testing the slagging property of chemical coal according to claim 6, characterized in that: The target data include the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod clamping groove.

8. The method for testing the slagging property of chemical coal according to claim 7, characterized in that: The real-time acquisition of target data by the target device includes: The pressure sensor (105a) and the displacement sensor (105b) are used to respectively collect the force data of the scraping tool and the displacement data of the scraping tool relative to the slag rod clamping groove in real time.

9. The method for testing the slagging property of chemical coal according to any one of claims 6 to 8, characterized in that: The other parameters include slag type assignment Ncm, characterization temperature and calorific value correction factor ζ.

10. The method for testing the slagging property of chemical coal according to claim 9, characterized in that: The slag type assignment Ncm includes five levels: molten, viscous, strongly cohesive, cohesive, and weakly cohesive.

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