DE202023106595U1 - Coal-fired boilers with liquid slag discharge - Google Patents

Abstract

Coal-fired boiler with liquid slag discharge, characterized in that it comprises:
a boiler body comprising an upper firebox and a lower firebox,
wherein the upper firebox and the lower firebox are connected to each other, and the upper firebox is arranged above the lower firebox, the side wall of the upper firebox being provided with a sofa wind nozzle, a burner and an oil spray nozzle in the top-down direction, wherein the oil spray nozzle is disposed close to the lower firebox, the burner is disposed between the couch tuyere and the oil spray nozzle, the burner and the couch tuyere are spaced apart by a first predetermined distance, and the burner and the oil spray nozzle are spaced apart by a second predetermined distance are, wherein the second predetermined distance is greater than the first predetermined distance; and wherein a slag discharge opening is provided at the bottom of the lower firebox.

Description

TECHNICAL FIELD

The present application relates to the technical field of boilers, in particular to a coal-fired boiler with liquid slag discharge.

STATE OF THE ART

China's Xinjiang has huge reserves of highly alkaline coal, This coal contains high levels of Na, K and other alkali and alkaline earth metals. At present, solid-state slag discharge is still mainly used for the operation of domestic coal-fired boilers. Solid slag boilers are prone to slagging and fouling when burning highly alkaline coals. The resulting serious slagging and fouling problems affect the long-term, safe and reliable operation of the boiler, thereby limiting the development and use of highly alkaline coal as thermal coal.

CONTENT OF THIS USER MODEL

The present application aims to solve, at least to some extent, one of the technical problems of the prior art.

For this purpose, the object of the present application is to propose a coal-fired boiler with liquid slag discharge, in which the side wall of the upper combustion chamber is provided with a sofa wind nozzle, a burner for the primary combustion of coal dust, and an oil spray nozzle arranged below the burner for spraying oil is, thereby forming a new flame center for the secondary combustion of liquid slag and unburned coal dust. Since the oil spray nozzle is located near the lower firebox, the temperature of the lower firebox can be effectively increased, so that a continuous and stable liquid slag film is formed on the inner wall surface of the lower firebox, which enables the liquid slag to be discharged.

In order to achieve the above object, the coal-fired liquid slag discharge boiler proposed by the present application includes a boiler body comprising an upper firebox and a lower firebox, the upper firebox and the lower firebox being connected to each other, and the upper Firebox is arranged above the lower firebox. The side wall of the upper firebox is provided with a sofa wind nozzle, a burner and an oil spray nozzle in the top-down direction, the oil spray nozzle is arranged close to the lower fire chamber, and the burner is arranged between the sofa wind nozzle and the oil spray nozzle. The burner and the sofa wind nozzle are spaced apart by a first predetermined distance. The burner and the oil spray nozzle are spaced apart a second predetermined distance, the second predetermined distance being greater than the first predetermined distance. A slag discharge opening is provided at the bottom of the lower firebox.

Further, it is stated that it further includes an oxygen spray opening provided on the side wall of the lower combustion chamber, wherein the oxygen spray opening is arranged between the oil spray nozzle and the slag discharge opening.

Furthermore, it is stated that it further comprises an oxygen supply device, the oxygen supply device being movably provided at the oxygen injection opening, the oxygen supply device having an oxygen supply position and a release position, the oxygen supply device partially protruding into the oxygen injection opening when the oxygen supply device is in the oxygen supply position, and the oxygen supply device is triggered from the oxygen injection opening when the oxygen supply device is in the trigger position.

Further, it is stated that the oxygen supply device includes: an oxygen tank; a gas delivery line having opposite first and second ends in its extension direction, the first end of the gas delivery line communicating with the oxygen tank; and a sprayer communicating with the second end of the gas delivery line, the sprayer being movably provided at the oxygen spray opening.

Further, it is designed that the sprayer is provided at the oxygen spray opening at a predetermined angle with respect to the wall surface of the lower combustion chamber.

Furthermore, it is designed that the sprayer comprises a spray pipe and a nozzle, with the spray pipe and the nozzle communicating with one another. The nozzle includes an expanded portion and a narrowed portion, the expanded portion and the narrowed portion communicating with each other and the inner diameter of the ver narrowed section is at least 1/2 smaller than the inner diameter of the expanded section.

Furthermore, it is designed that a valve and a check valve are provided within the jet pipe.

It is further configured to further include a controller, a plurality of temperature sensors being provided on the peripheral sidewalls of the lower firebox, each of the plurality of temperature sensors and the sprayer being electrically connected to the controller.

Furthermore, it is stated that the wall surface of the lower firebox is formed in an oblique structure and the inner diameter of the lower firebox progressively decreases in the direction from top to bottom.

Furthermore, it is stated that a plurality of oxygen spray openings are present, the plurality of oxygen spray openings being arranged at a distance in the side wall circumferential direction of the lower combustion chamber and the plurality of oxygen spray openings being arranged in the same horizontal plane.

Further aspects and advantages of the present application are partly mentioned in the following description, partly they arise from the following description or become known through the practice of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

• 1 ist eine schematische strukturelle Darstellung eines kohlebefeuerten Kessels mit Flüssigschlackenaustrag, der in einem Ausführungsbeispiel der vorliegenden Anmeldung vorgeschlagen wird;
• 2 ist eine schematische strukturelle Darstellung einer Sauerstoffzufuhrvorrichtung eines kohlebefeuerten Kessels mit Flüssigschlackenaustrag, der in einem anderen Ausführungsbeispiel der vorliegenden Anmeldung vorgeschlagen wird;
• 3 ist eine schematische strukturelle Darstellung eines Spritzers eines kohlebefeuerten Kessels mit Flüssigschlackenaustrag, der in einem anderen Ausführungsbeispiel der vorliegenden Anmeldung vorgeschlagen wird.

The above and/or additional aspects and advantages of the present application will be apparent and readily understood from the following description of embodiments taken in conjunction with the accompanying drawings, in which:

• 1 is a schematic structural representation of a coal-fired liquid slag discharge boiler proposed in an embodiment of the present application;
• 2 Fig. 10 is a schematic structural illustration of an oxygen supply device of a coal-fired liquid slag discharge boiler proposed in another embodiment of the present application;
• 3 is a schematic structural representation of a splasher of a coal-fired boiler with liquid slag discharge proposed in another embodiment of the present application.

DETAILED DESCRIPTION

Embodiments of the present application are described in detail below, and examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The exemplary embodiments described below with reference to the accompanying drawings are exemplary and serve only to explain the present application and are not to be understood as a limitation of the present application. Rather, the embodiments of the present application include all variations, modifications and equivalents that come within the spirit and meaning of the appended claims.

Referring to 1 until 3 a coal-fired boiler 100 with liquid slag discharge comprises a boiler body 1 which comprises an upper firebox 11 and a lower firebox 12, the upper firebox 11 and the lower firebox 12 being connected to one another, and the upper firebox 11 being arranged above the lower firebox 12; wherein the side wall of the upper firebox 11 is provided with a sofa wind nozzle 2, a burner 3 and an oil spray nozzle 4 in the top-down direction, the oil spray nozzle 4 is arranged close to the lower firebox 12, the burner 3 between the sofa wind nozzle 2 and the oil spray nozzle 4 are arranged, the burner 3 and the sofa wind nozzle 2 are spaced apart from one another by a first predetermined distance, the burner 3 and the oil spray nozzle 4 are spaced apart from one another by a second predetermined distance, the second predetermined distance being greater than the first predetermined distance Distance is, and a slag discharge opening 5 is provided at the bottom of the lower firebox 12.

The object of the present application is to propose a coal-fired boiler with liquid slag discharge, in which the side wall of the upper combustion chamber is provided with a sofa wind nozzle, a burner for the primary combustion of coal dust, and an oil spray nozzle is arranged below the burner for spraying oil , thereby forming a new flame center for the secondary combustion of liquid slag and unburned pulverized coal. Since the oil spray nozzle is located near the lower firebox, the temperature of the lower firebox can be effectively increased, so that a continuous and stable liquid slag film is formed on the inner wall surface of the lower firebox, which enables the liquid slag to be discharged.

A coal-fired boiler 100 with liquid slag discharge includes a boiler body 1, an oxygen spray opening 6 and an oxygen supply device 7.

The boiler body 1 includes an upper firebox 11 and a lower firebox 12, the upper firebox 11 and the lower firebox 12 being connected to each other, and the upper firebox 11 being arranged above the lower firebox 12; wherein the side wall of the upper firebox 11 is provided with a sofa wind nozzle 2, a burner 3 and an oil spray nozzle 4 in the top-down direction, the oil spray nozzle 4 is arranged close to the lower firebox 12, the burner 3 between the sofa wind nozzle 2 and the oil spray nozzle 4 are arranged, the burner 3 and the sofa wind nozzle 2 are spaced apart from one another by a first predetermined distance, the burner 3 and the oil spray nozzle 4 are spaced apart from one another by a second predetermined distance, the second predetermined distance being greater than the first predetermined distance Distance is, and a slag discharge opening 5 is provided at the bottom of the lower firebox 12.

In the present embodiment, the side wall of the upper firebox 11 is provided with a couch tuyere 2 and a burner 3 for the primary combustion of pulverized coal, and the burner 3 and the couch tuyere 2 are spaced apart from each other by a first predetermined distance, and the setting of the first predetermined distance is reduced by 40% with respect to the original vertical distance between the burner and the sofa wind nozzle, which helps improve combustion efficiency. The oil spray nozzle 4 is provided below the burner 2, the oil spray nozzle 4 is located near the lower combustion chamber 12, the second predetermined distance is greater than the first predetermined distance. The oil spray from the oil spray nozzle 4 can cause secondary combustion in the lower combustion chamber 12, so that the coal dust is sufficiently burned and the coal slag is liquefied. The liquefied coal slag can be discharged via the slag discharge opening 5.

In addition, the oxygen spray opening 6 is provided on the side wall of the lower combustion chamber 12, the oxygen spray opening 6 being arranged between the oil spray nozzle 4 and the slag discharge opening 5. The oxygen supply device 7 is movably provided at the oxygen injection port 6. The oxygen supply device 7 has an oxygen supply position and a release position, the oxygen supply device 7 partially protruding into the oxygen injection opening 6 when the oxygen supply device 7 is in the oxygen supply position, and the oxygen supply device 7 is triggered from the oxygen injection opening 6 when the oxygen supply device is in the release position is..

In order to sufficiently burn the oil spray from the oil spray nozzle, the oxygen supply device 7 is provided at the oxygen spray port 6 to supply oxygen to the lower firebox 12 so that a new flame center is formed in the lower firebox 12. This mixes the combustible material in the liquid slag and the sprayed oil droplets to form secondary combustion and enhance the wall-slinging effect of the liquid after mixing. In connection with the blowing off of the oxygen supply device 7, the liquid slag can fall down to the slag discharge opening 5, thereby preventing coking on the wall.

The oxygen supply device 7 further comprises an oxygen tank 71, a gas delivery line 72 and a sprayer 73.

The gas delivery line 72 has opposite first and second ends in its direction of extension, the first end of the gas delivery line communicating with the oxygen tank;

The sprayer 73 communicates with the second end of the gas delivery line 72, the sprayer 73 being movably provided at the oxygen spray opening 6.

The sprayer 6 is provided at the oxygen spray port 6 at a predetermined angle with respect to the wall surface of the lower firebox 12.

In the present embodiment, the sprayer 6 is disposed at an angle of 95°-100° with respect to the wall surface of the lower combustion chamber 12 at the oxygen spray port 6, and the oxygen ejected from the sprayer 73 and the oil injected from the sprayer are mixed and burned completely in the lower firebox 12. Thus, it is possible to effectively control the temperature of the liquid ash in the lower firebox 12 to keep it above 1200° C., which is higher than the slagging temperature of the highly alkaline coal. At the same time, the oxidative atmosphere in the lower firebox is maintained to let the unburned part of the ash burn out in the secondary combustion and improve the combustion efficiency of coal combustion.

The sprayer 73 includes a spray tube 731 and a nozzle 732, the spray tube 731 and the nozzle 732 communicating with each other, the nozzle 732 includes an expanded portion and a narrowed portion, the expanded portion and the narrowed portion communicate with each other, and the inner diameter of the narrowed portion is at least 1/2 smaller than the inner diameter of the expanded portion. The special nozzle design can make it possible to accelerate the speed of spraying the oxygen so that it can better blow off the inner wall of the lower firebox 12.

A valve 8 and a check valve 9 are provided within the spray pipe 731. The valve 8 is used to control the oxygen flow rate to allow easy adjustment and the check valve 9 prevents the oxygen from flowing back to increase safety.

The coal-fired boiler 100 with liquid slag discharge 100 further includes a controller, a plurality of temperature sensors being provided on the peripheral sidewalls of the lower combustion chamber 12, each of the plurality of temperature sensors and the splasher being electrically connected to the controller. In the present exemplary embodiment, the temperature sensors can be thermocouples with a large temperature measurement range. Specifically, thermocouples are provided on the wall surface of the lower firebox between the oil spray nozzle and the oxygen spray port and on the wall surface of the lower firebox between the oxygen spray port and the slag discharge port. The thermocouples are arranged on the wall surface of the lower firebox at a distance of 1 m, and the thermocouples extend 2 meters into the furnace room, and the temperature data measured by the thermocouples are input into the controller through the integration.

The wall surface of the lower firebox 12 is formed into an oblique structure, and the inner diameter of the lower firebox 12 progressively decreases in the top-down direction. The slag in the liquid state naturally flows downward due to gravity and is discharged from the slag discharge opening.

A plurality of oxygen spray openings 6 are provided, the plurality of oxygen spray openings 6 being spaced apart in the sidewall circumferential direction of the lower combustion chamber 12, and the plurality of oxygen spray openings 6 being arranged in the same horizontal plane. With such an arrangement, the oxygen expelled from the wall surface of the lower firebox 12 can form a new, strong reflux zone in the lower firebox 12, which can increase the wall-slinging effect of the liquid slag drops and increase the residence time of the high-temperature flue gases in the lower firebox.

It should be noted that in the description of the present application, the terms "first", "second" and the like are used for descriptive purposes only and are not to be understood as indicating or implying any relative meaning. Additionally, as used in the specification of this application, "a plurality of" means two or more unless otherwise stated.

Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment, or portion of code that includes one or more executable instructions for implementing the steps of a particular logical function or process, and the scope of the preferred embodiments of the present application includes additional implementations that may be implemented in a different order than shown or discussed. The embodiments of the present application may be executed in the same manner or in reverse order to perform the functions as it is should be understandable to those skilled in the art to which the embodiments of this application pertain.

As used in this specification, the terms “an embodiment,” “some embodiments,” “example,” “specific examples,” or “specific examples” refer to a particular feature, structure, material, or material Feature described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this description, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Additionally, the specific features, structures, materials, or properties described may be appropriately combined in one or more embodiments or examples.

Although embodiments of the present application have been shown and described above, the above embodiments are exemplary and not limiting of the present application, and those skilled in the art may make changes within the scope of the present application. Make modifications, substitutions and variations of the above embodiments.

Claims (10)

A coal-fired boiler with liquid slag discharge, characterized in that it comprises: a boiler body comprising an upper firebox and a lower firebox, the upper firebox and the lower firebox being connected to each other, and the upper firebox being arranged above the lower firebox, wherein the side wall of the upper firebox is provided with a sofa wind nozzle, a burner and an oil spray nozzle in the top-down direction, the oil spray nozzle is arranged close to the lower fire chamber, the burner is arranged between the sofa wind nozzle and the oil spray nozzle, the the burner and the couch wind nozzle are spaced apart by a first predetermined distance, and the burner and the oil spray nozzle are spaced apart by a second predetermined distance, the second predetermined distance being greater than the first predetermined distance; and wherein a slag discharge opening is provided at the bottom of the lower firebox. Coal-fired boiler with liquid slag discharge Claim 1 , characterized in that it further comprises an oxygen spray port provided on the side wall of the lower combustion chamber, the oxygen spray port being disposed between the oil spray nozzle and the slag discharge port. Coal-fired boiler with liquid slag discharge Claim 2 , characterized in that it further comprises an oxygen supply device, the oxygen supply device being movably provided at the oxygen injection port, and the oxygen supply device having an oxygen supply position and a release position, the oxygen supply device partially protruding into the oxygen injection opening when the oxygen supply device is in the oxygen supply position, and the oxygen supply device is triggered from the oxygen injection opening when the oxygen supply device is in the trigger position. Coal-fired boiler with liquid slag discharge Claim 3 , characterized in that the oxygen supply device comprises: an oxygen tank; a gas delivery line having opposite first and second ends in its extension direction, the first end of the gas delivery line communicating with the oxygen tank; and a sprayer communicating with the second end of the gas delivery line, the sprayer being movably provided at the oxygen spray opening. Coal-fired boiler with liquid slag discharge Claim 4 , characterized in that the sprayer is provided at the oxygen spray opening at a predetermined angle with respect to the wall surface of the lower combustion chamber. Coal-fired boiler with liquid slag discharge Claim 4 , characterized in that the sprayer comprises a spray tube and a nozzle, the spray tube and the nozzle communicating with each other, and wherein the nozzle comprises an expanded section and a narrowed section, the expanded section and the narrowed section communicate with each other and the inner diameter of the narrowed Section is at least 1/2 smaller than the inner diameter of the expanded section. Coal-fired boiler with liquid slag discharge Claim 6 , characterized in that a valve and a check valve are provided within the jet pipe. Coal-fired boiler with liquid slag discharge Claim 4 , characterized in that it further comprises a controller, a plurality of temperature sensors being provided on the peripheral side walls of the lower firebox, each of the plurality of temperature sensors and the sprayer being electrically connected to the controller. Coal-fired boiler with liquid slag discharge Claim 1 , characterized in that the wall surface of the lower firebox is formed in an oblique structure and the inner diameter of the lower firebox progressively decreases in the direction from top to bottom. Coal-fired boiler with liquid slag discharge Claim 2 , characterized in that there are a plurality of oxygen spray openings, the plurality of oxygen spray openings being spaced apart in the side wall circumferential direction of the lower combustion chamber, and the plurality of oxygen spray openings being arranged in the same horizontal plane.

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