Buried scraper coal feeder

Abstract

Disclosed is a buried scraper coal feeder, comprising: a housing (1), the housing (1) being provided with a coal inlet and a coal outlet; a hopper (5), a discharge port of the hopper (5) being in communication with the coal inlet of the housing (1); a weighing belt coal feeding device (2), the weighing belt coal feeding device (2) being arranged in the housing (1) and corresponding to the coal inlet in position; and a scraper-conveying coal feeding device (4), the scraper-conveying coal feeding device (4) being arranged corresponding to the coal outlet of the housing (1) and being used for conveying coal output from the coal outlet to a coal mill. By means of providing the housing (1), the coal feeder can effectively prevent the weighing belt coal feeding device (2) from being affected by high temperatures outside the housing (1), thereby achieving accurate measurement of coal feeding amount, and further avoiding ignition of weighing functional parts of the weighing belt coal feeding device (2).

Description

A type of buried scraper feeder Technical Field

[0001] The embodiments disclosed herein belong to the technical field of coal feeding equipment, specifically relating to a submerged scraper coal feeder. Background Technology

[0002] The operation of a fan mill requires a submerged scraper feeder, which is the main coal feeding equipment in the pulverizing system. It features uniform coal feeding and can continuously deliver coal (with stepless adjustment based on operating conditions) into the fan mill. The submerged scraper feeder can meet the requirements for feeding over long distances, and its sealed housing structure is suitable for operation under both positive and negative pressure conditions.

[0003] However, when a scraper feeder is paired with a fan mill, the air source for the fan mill is generally taken from the flue gas inside the boiler. With the addition of hot secondary air and cold flue gas, the internal ambient temperature of the mill reaches over 500℃, and the ambient temperature at the bottom of the feeder can reach up to 800℃. If the pulverizing system reverses pressure, it will cause high temperatures inside the feeder, which seriously affects the operation of the weighing module inside the scraper feeder. This results in a large error in the feeder's metering, which seriously affects the calculation of coal consumption for power supply and the inventory count within the plant.

[0004] Therefore, how to solve the above problems has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The embodiments disclosed herein are intended to at least address one of the technical problems existing in the prior art, and to provide a buried scraper feeder.

[0006] One aspect of the embodiments of this disclosure provides a buried scraper feeder, comprising: a housing having a coal inlet and a coal outlet;

[0007] The hopper has a discharge port that is connected to the coal inlet of the machine casing;

[0008] A weighing belt coal conveyor, wherein the weighing belt coal conveyor is installed inside the casing and corresponds to the position of the coal inlet;

[0009] A scraper-type coal feeding device is provided, which is correspondingly arranged with the coal outlet of the machine casing, and is used to transport the coal discharged from the coal outlet to the coal mill.

[0010] Furthermore, the coal feeder also includes an upper discharge pipe, the inlet end of which is connected to the discharge port of the hopper, and the outlet end of which is connected to the coal inlet of the machine casing.

[0011] Furthermore, the coal feeder also includes: a coal feeder upper plate, which is inserted into the upper discharge pipe and is used to adjust the discharge flow rate of the upper discharge pipe.

[0012] Furthermore, the coal feeder also includes a dropping pipe, the inlet end of which is connected to the coal outlet of the machine casing, and the outlet end of which corresponds to the position of the scraper-type coal feeding device. The dropping pipe guides coal to the scraper-type coal feeding device through its outlet end.

[0013] Furthermore, the coal feeder also includes a lower feeder plate, which is inserted into the lower feed pipe and is used to adjust the feed flow rate of the lower feed pipe.

[0014] Optionally, the weighing belt coal conveyor includes a weighing drive wheel and a weighing driven wheel that are spaced apart from each other in the housing, a weighing belt wound around the weighing drive wheel and the weighing driven wheel, and a pressure sensor disposed in the housing and in contact with the weighing belt for measuring the mass carried by the weighing belt.

[0015] Furthermore, the coal feeder also includes a chain cleaning device, which is disposed inside the machine casing and spaced apart from the weighing belt coal conveyor. The chain cleaning device is used to clean the coal falling off the bottom wall of the machine casing.

[0016] Optionally, the chain cleaning device includes a chain drive wheel and a chain driven wheel that are spaced apart within the housing, a chain that is wound around the chain drive wheel and the chain driven wheel, and a chain scraper that is disposed on the chain and contacts the bottom wall of the housing.

[0017] Optionally, the scraper-type coal feeding device includes a housing supporting the machine casing, a coal feeding drive wheel and a coal feeding driven wheel disposed opposite to each other within the housing, a scraper conveyor belt wound around the coal feeding drive wheel and the coal feeding driven wheel, and a scraper disposed on the scraper conveyor belt; the housing has a coal drop outlet communicating with the coal outlet of the machine casing, and a coal conveying outlet.

[0018] Furthermore, the coal feeder also includes: a coal conveying pipe and a coal feeding plate, wherein the inlet end of the coal conveying pipe is connected to the coal conveying port of the shell, and the outlet end of the coal conveying pipe is connected to the coal mill; the coal feeding plate is inserted into the coal conveying pipe and is used to adjust the coal conveying flow rate of the coal conveying pipe.

[0019] The beneficial effects of the embodiments of this disclosure include:

[0020] In this invention, by setting up a casing, the weighing belt coal conveyor installed inside the casing can be effectively protected from the influence of high temperature outside the casing. This not only enables accurate measurement of coal feed, but also prevents the weighing function of the weighing belt coal conveyor from catching fire. Attached Figure Description

[0021] Figure 1 is a structural schematic diagram of a buried scraper feeder according to an embodiment of the present disclosure.

[0022] 1. Casing; 2. Weighing belt coal feeding device; 3. Chain cleaning device; 4. Scraper conveyor coal feeding device; 5. Hopper; 6. Upper feed pipe; 7. Lower feed pipe; 8. Upper feeder plate; 9. Lower feeder plate; 10. Coal conveying pipe; 11. Coal feeder plate; 12. Support component; 21. Weighing drive wheel; 22. Weighing driven wheel; 23. Weighing belt; 24. Pressure sensor; 31. Chain drive wheel; 32. Chain driven wheel; 33. Chain; 34. Chain scraper; 41. Housing; 42. Coal feed drive wheel; 43. Coal feed driven wheel; 44. Scraper conveyor belt. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] The embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. The detailed descriptions and accompanying drawings of the following embodiments are used to exemplarily illustrate the principles of this application, but should not be used to limit the scope of this application; that is, this application is not limited to the described embodiments. In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicating orientation or positional relationships are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range.

[0025] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application depending on the specific circumstances.

[0026] As shown in Figure 1, a submerged scraper feeder includes a casing 1, a hopper 5, a weighing belt conveyor 2, and a scraper conveyor 4. The casing 1 has a coal inlet and a coal outlet. The discharge port of the hopper 5 is connected to the coal inlet of the casing 1. The weighing belt conveyor 2 is installed inside the casing 1 and corresponds to the position of the coal inlet. The scraper conveyor 4 is correspondingly installed to the coal outlet of the casing 1 and is used to transport the coal discharged from the coal outlet to the coal mill.

[0027] In this invention, by setting the housing 1, the weighing belt coal conveyor 2 installed inside the housing 1 can be effectively protected from the high temperature outside the housing 1. This not only enables accurate measurement of coal feed, but also prevents the weighing function of the weighing belt coal conveyor 2 from catching fire.

[0028] In some embodiments, the coal feeder also includes an upper discharge pipe 6, the inlet end of which is connected to the discharge port of the hopper 5, and the outlet end of which is connected to the coal inlet of the casing 1.

[0029] In some embodiments, the coal feeder also includes a coal feeder upper plate 8, which is inserted into the upper discharge pipe 6 and is used to adjust the discharge flow rate of the upper discharge pipe 6.

[0030] In some embodiments, the coal feeder also includes a drop pipe 7, the inlet end of which is connected to the coal outlet of the casing 1, and the outlet end of the drop pipe 7 is positioned corresponding to the scraper-type conveying coal feeder 4. The drop pipe 7 guides the coal to the scraper-type conveying coal feeder 4 through its outlet end.

[0031] In some embodiments, the coal feeder also includes a lower feeder plate 9, which is inserted into the lower feed pipe 7 and is used to adjust the discharge flow rate of the lower feed pipe 7.

[0032] In some embodiments, the weighing belt coal conveyor 2 includes a weighing drive wheel 21 and a weighing driven wheel 22 disposed relatively apart in the housing 1, a weighing belt 23 wound around the weighing drive wheel 21 and the weighing driven wheel 22, and a pressure sensor 24 disposed in the housing 1 and abutting against the weighing belt 23 for measuring the mass carried by the weighing belt 23.

[0033] In some embodiments, the coal feeder also includes a chain cleaning device 3, which is disposed inside the housing 1 and spaced apart from the weighing belt coal conveying device 2. The chain cleaning device 3 is used to clean the coal falling off the bottom wall of the housing 1.

[0034] In some embodiments, the chain cleaning device 3 is provided with a chain drive wheel 31 and a chain driven wheel 32 disposed at a distance from each other in the housing 1, a chain 33 wound around the chain drive wheel 31 and the chain driven wheel 32, and a chain scraper 34 disposed on the chain 33 and in contact with the bottom wall of the housing 1.

[0035] In some embodiments, the scraper-type coal feeding device 4 includes a housing 41 supporting the housing 1, a coal feeding drive wheel 42 and a coal feeding driven wheel 43 disposed opposite to each other within the housing 41, a scraper conveyor belt 44 wound around the coal feeding drive wheel 42 and the coal feeding driven wheel 43, and a scraper disposed on the scraper conveyor belt 44. The housing 41 has a coal drop port communicating with the coal outlet of the housing 1, and a coal conveying port.

[0036] In some embodiments, the coal feeder also includes a coal conveying pipe 10 and a coal feeding plate 11. The inlet end of the coal conveying pipe 10 is connected to the coal conveying port of the housing 41, and the outlet end of the coal conveying pipe 10 is connected to the coal mill. The coal feeding plate 11 is inserted into the coal conveying pipe 10 to adjust the coal conveying flow rate of the coal conveying pipe 10.

[0037] Specifically, the weighing belt conveyor 2 and the scraper conveyor 4 are distributed vertically and alternately within the casing 1. The hopper 5 has a diameter of 800-1000 mm, and the feeder is also equipped with weighing idlers that contact the weighing belt 23. The chain cleaning device 3 is equipped with a chain scraper 34 that contacts the bottom wall of the casing 1 to clean coal dust from the bottom wall of the casing 1.

[0038] The casing 1 has openings on both sides, and the openings are connected to the outlet pipes of the cold secondary air or micro-oil distribution fan, serving as the sealing air for the coal feeder.

[0039] The motors for the chain drive wheel 31 and the weighing drive wheel 21 are both variable frequency motors, and the motor frequency of the coal feeding drive wheel 42 is the same as that of the motors for the chain drive wheel 31 and the weighing drive wheel 21. The coal feeder also includes a coal flow indicator and a control box, and the pressure sensor 24, the coal flow indicator, and the control box are all electrically connected to the motors.

[0040] The raw coal in hopper 5 falls onto the upper part of weighing belt 23 (rubber belt) via the upper feeder plate 8 on the upper feed pipe 6. During the movement of weighing belt 23, the coal feed rate is measured in real time through the pressure sensor 24 signal and the speed signal of weighing belt 23. The raw coal enters the housing 41 directly through the lower feeder plate 9 on the lower feed pipe 7, and is then conveyed to the inside of the fan mill at the same frequency by the feed drive wheel 42 motor, completing the entire process.

[0041] The coal feeder control logic includes:

[0042] Enable permission:

[0043] The coal mill is operating with a scraper feeder embedded in it.

[0044] The ignition energy at this corner is sufficient;

[0045] The lower baffle plate of the coal feeder is opened;

[0046] The coal mill outlet temperature is suitable;

[0047] No tripping conditions.

[0048] Protection stop:

[0049] The coal mill tripped;

[0050] The lower baffle plate of the coal feeder is closed;

[0051] Boiler MFT;

[0052] Abnormal tripping;

[0053] Manual shutdown;

[0054] The buried scraper feeder is stopped;

[0055] The scraper feeder receives signals indicating coal shortage or chain breakage.

[0056] The control logic for the lower feeder plate includes:

[0057] Automatically open:

[0058] When the operation signal of the scraper feeder arrives, the lower plate of the feeder opens automatically.

[0059] Automatic shutdown:

[0060] When the chain break signal of the scraper feeder is received, the lower plate of the feeder will automatically close.

[0061] When a coal cut-off signal is received from a scraper feeder or a weighing belt conveyor, the lower plate of the feeder will automatically close.

[0062] When an overheating signal is received from the scraper feeder, the lower baffle of the feeder will automatically close.

[0063] When the stop signal for the scraper feeder arrives, the lower plate of the feeder will automatically close.

[0064] When the coal mill trips due to an abnormality, the lower baffle of the coal feeder automatically closes.

[0065] When the boiler MFT signal arrives, the lower baffle of the coal feeder automatically closes.

[0066] Other control logic includes:

[0067] The coal fire detection judgment condition is changed to the coal quantity signal from the weighing coal feeder with an added delay time, and then the fire detection is started. The micro-oil fire detection takes the micro-oil mode signal and is not associated with the coal feeder.

[0068] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.

Claims

An en masse coal feeder, characterized in that, include: A housing having a coal inlet and a coal outlet; The hopper has a discharge port that is connected to the coal inlet of the machine casing; A weighing belt coal conveyor, wherein the weighing belt coal conveyor is installed inside the casing and corresponds to the position of the coal inlet; A scraper-type coal feeding device is provided, which is correspondingly arranged with the coal outlet of the machine casing, and is used to transport the coal discharged from the coal outlet to the coal mill. The scraper-type coal feeder according to claim 1, characterized in that, The coal feeder further includes an upper discharge pipe, the inlet end of which is connected to the discharge port of the hopper, and the outlet end of which is connected to the coal inlet of the machine casing. The scraper-type coal feeder according to claim 2, characterized in that, The coal feeder also includes an upper feeder plate, which is inserted into the upper discharge pipe and is used to adjust the discharge flow rate of the upper discharge pipe. The scraper-type coal feeder according to claim 1, characterized in that, The coal feeder further includes a dropping pipe, the inlet end of which is connected to the coal outlet of the machine casing, and the outlet end of which corresponds to the position of the scraper-type coal feeding device. The dropping pipe guides coal to the scraper-type coal feeding device through its outlet end. The scraper-type coal feeder according to claim 4, characterized in that, The coal feeder further includes a lower feeder plate, which is inserted into the lower feed pipe and is used to adjust the feed flow rate of the lower feed pipe. The scraper-type coal feeder according to claim 1, characterized in that, The weighing belt coal conveyor includes a weighing drive wheel and a weighing driven wheel that are spaced apart from each other in the housing, a weighing belt that is wound around the weighing drive wheel and the weighing driven wheel, and a pressure sensor that is disposed in the housing and abuts against the weighing belt and is used to measure the load-bearing mass of the weighing belt. The scraper-type coal feeder according to claim 1, characterized in that, The coal feeder further includes a chain cleaning device, which is disposed inside the casing and spaced apart from the weighing belt coal conveyor. The chain cleaning device is used to clean the coal falling off the bottom wall of the casing. The en masse coal feeder according to claim 7, characterized in that, The chain cleaning device consists of a chain drive wheel and a chain driven wheel that are spaced apart within the housing, a chain that is wound around the chain drive wheel and the chain driven wheel, and a chain scraper that is disposed on the chain and contacts the bottom wall of the housing. The scraper-type coal feeder according to claim 1, characterized in that, The scraper-type coal feeding device includes a housing supporting the machine casing, a coal feeding drive wheel and a coal feeding driven wheel disposed opposite to each other within the housing, a scraper conveyor belt wound around the coal feeding drive wheel and the coal feeding driven wheel, and a scraper disposed on the scraper conveyor belt; the housing has a coal drop outlet communicating with the coal outlet of the machine casing, and a coal conveying outlet. The en masse coal feeder according to claim 9, characterized in that, The coal feeder further includes: a coal conveying pipe and a coal feeding plate. The inlet end of the coal conveying pipe is connected to the coal conveying port of the shell, and the outlet end of the coal conveying pipe is connected to the coal mill. The coal feeding plate is inserted into the coal conveying pipe and is used to adjust the coal conveying flow rate of the coal conveying pipe.

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