CN-122006877-A - Material recycling system and method for coal mill

CN122006877ACN 122006877 ACN122006877 ACN 122006877ACN-122006877-A

Abstract

The invention relates to the technical field of boilers and discloses a material recovery system and a material recovery method of a coal mill, wherein the material recovery system of the coal mill comprises a collecting assembly, a sorting assembly, a fan, a mixer and a recovery pipeline, the sorting assembly comprises a feed port, a first discharge port and a second discharge port, the feed port is connected with the collecting assembly, the sorting assembly is used for receiving a mixture from the collecting assembly and sorting the mixture, pebble coal is discharged from the first discharge port, combustible components are discharged from the second discharge port, an air inlet of the fan is communicated with the sorting assembly, the fan is used for driving the mixture to flow, both the air inlet and the air outlet can be communicated with the outside, and the mixer is used for receiving the combustible components of the second discharge port, mixing the combustible components with positive pressure airflow from the fan and conveying the combustible components back to the coal mill. The material recovery system of the coal mill can realize separation and return of the combustible effective raw coal in the pebble coal, improve the utilization rate of the raw coal and avoid damage of the coal mill.

Inventors

WANG YAN
YANG PEIJUN
YUAN PANFENG
LI ZHENDONG
GAO MINGYANG
ZHAO WEIDONG
LIU DINGPO

Assignees

西安西热锅炉环保工程有限公司

Dates

Publication Date: 20260512
Application Date: 20260209

Claims (10)

1. A coal pulverizer material recovery system, comprising: A collection assembly for receiving the mixture discharged from the coal mill; The sorting assembly comprises a feed inlet, a first discharge outlet and a second discharge outlet, the feed inlet is connected with the collecting assembly, the sorting assembly is used for receiving the mixture from the collecting assembly and sorting the mixture, so that the pebble coal is discharged from the first discharge outlet, and the combustible component is discharged from the second discharge outlet; The air inlet of the fan is communicated with the sorting assembly and is used for generating negative pressure air flow for driving the mixture to flow in the sorting assembly, and positive pressure air flow is formed at the air outlet of the fan after the negative pressure air flows through the fan, wherein the air inlet and the air outlet can be communicated with the outside; The mixer is communicated with the second discharging port of the sorting assembly and the air outlet of the fan, and is used for receiving the combustible components of the second discharging port and mixing the combustible components with positive pressure air flow from the fan; And the recovery pipeline is arranged between the mixer and the coal mill and is used for conveying the pulverized coal carried by the positive pressure air flow back to the coal mill.
2. The coal pulverizer material recovery system of claim 1, further comprising: The sorting assembly further comprises a suction port, and the suction port is communicated with the air inlet through the first pipeline; the air supplementing pipeline is communicated with the first pipeline and is used for being communicated with the outside; And the air supplementing valve is arranged on the air supplementing pipeline.
3. The coal pulverizer material recovery system of claim 2, further comprising: The second pipeline is communicated with the air outlet of the fan and the mixer; an exhaust duct communicating with the second duct, the exhaust duct being for communication with the outside, And the exhaust valve is arranged on the exhaust pipeline.
4. The coal pulverizer material recovery system of claim 3, wherein the sorting assembly further comprises: The first gathering part is arranged on one side close to the feed inlet, and the lower end of the first gathering part forms the first discharge outlet; The second gathering part is arranged at one side far away from the feed inlet, and the lower end of the second gathering part forms the second discharge hole; The gas-solid separator is arranged at the suction port and is used for separating combustible components carried in the negative pressure airflow, the separated combustible components flow towards the second discharge port under the dead weight, and the separated negative pressure airflow flows through the first pipeline and enters the fan.
5. The coal pulverizer material recovery system of claim 4, wherein the mixer comprises: A housing; The rotary distributor is arranged in the middle of the shell and is provided with a rotary shaft and a plurality of distributing bins circumferentially arranged around the rotary shaft; one end of the feeding pipeline is communicated with the second discharge port, and the other end of the feeding pipeline is arranged in the shell and is positioned above the rotary distributor; The material collecting barrel is provided with a first end and a second end along the axial direction, the material collecting barrel is communicated with the shell and is positioned below the rotary distributor, the rotary distributor rotates at a preset rotating speed, a plurality of material distributing bins sequentially receive combustible components conveyed by the feeding pipeline and transfer the combustible components into the material collecting barrel, and an air outlet of the fan is communicated with the first end of the material collecting barrel through the second pipeline; The negative pressure interface is arranged on the shell and is positioned above the rotary distributor, and the negative pressure interface is communicated with the sorting assembly through a pipeline, so that part of positive pressure airflow entering through the material collecting barrel can be introduced into the sorting assembly by the negative pressure airflow.
6. The coal pulverizer material recovery system of claim 5, wherein the recovery pipeline includes a main recovery pipeline and a plurality of recovery branch pipelines that communicate with the main recovery pipeline, the main recovery pipeline with the second end intercommunication of aggregate cylinder, a plurality of the recovery branch pipelines with a plurality of the coal inlet one-to-one of coal pulverizer is connected, be equipped with the recovery valve on the recovery branch pipeline.
7. The coal pulverizer material recovery system of claim 1, wherein, The collecting assembly is connected with at least one coal mill, or The collection components are multiple, and the collection components are connected with the coal mills in a one-to-one correspondence mode.
8. The coal pulverizer material recovery system of claim 1, wherein the collection assembly has a chamber and includes a feed end in communication with the chamber, an inlet end connected to the pulverizer slag discharge port via a conduit, and a discharge end connected to the separator assembly feed port, the inlet end for introducing air to compensate for an internal pressure differential of the aggregate unit and to provide auxiliary power to the flow of the mixture within the aggregate unit; The feeding end, the air inlet end and the discharging end are respectively provided with a feeding valve, an air inlet valve and a discharging valve.
9. The coal pulverizer material recovery system of claim 3, further comprising: a pressure sensor disposed on at least one of the second conduit and the sorting assembly; The control system is in communication connection with the fan, the air supplementing valve, the exhaust valve and the pressure sensor and is used for controlling the start and stop of the fan and controlling the opening and closing of the air supplementing valve and/or the exhaust valve according to signals or preset instructions of the pressure sensor.
10. A method of coal mill material recovery, characterized in that it is implemented with the coal mill material recovery system of any one of claims 1-9, comprising: The air inlet and the air outlet of the fan are communicated with the outside, the sorting assembly stops sorting, and the combustible components are stopped being conveyed to the coal mill; the separation state is that an air inlet of the fan is communicated with the separation assembly, and an air outlet of the fan is communicated with the outside so as to improve the kinetic energy of the negative pressure air flow and carry out the transportation and separation of the mixture; The recovery state is that the air inlet of the fan is communicated with the outside, and the air outlet is communicated with the mixer so as to improve the kinetic energy of the positive pressure air flow and convey the combustible components to the coal mill; And in a conventional state, an air inlet of the fan is communicated with the separation assembly, an air outlet of the fan is communicated with the mixer, the negative pressure air flow and the positive pressure air flow are balanced, and the mixture is conveyed and separated at the same time, and the combustible components are conveyed to the coal mill.

Description

Material recycling system and method for coal mill Technical Field The invention belongs to the technical field of boilers, and particularly relates to a material recovery system and method of a coal mill. Background The coal mill can produce stone coal during operation. The pebble coal mainly comprises gangue, crushed coal blocks, pebbles, pulverized coal and other sundries. Especially when the quality of raw coal is poor and the running condition of the coal mill is bad, the stone coal emission of the medium-speed coal mill is greatly increased, and the content of the raw coal in the stone coal is more. In the related art, stone coal is added into raw coal and then enters a coal mill again for grinding. However, the reentry of the coal mill tends to cause the continuous increase of the pebble coal quantity of the coal mill, and at the same time, the stone and ore contained in the pebble coal can increase the abrasion of the coal mill. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, the embodiment of the invention provides a coal mill material recovery system which can realize separation and return of combustible effective raw coal in pebble coal, improve the utilization rate of the raw coal and avoid damage of a coal mill. The embodiment of the invention also provides a material recovery method of the coal mill, which can realize operation in various modes such as idling, sorting, recovery, normal and the like, and meets the requirements under different use scenes. The coal mill material recovery system comprises a collection assembly, a separation assembly, a fan, a mixer and a recovery pipeline, wherein the collection assembly is used for receiving a mixture discharged from a coal mill, the separation assembly comprises a feed port, a first discharge port and a second discharge port, the feed port is connected with the collection assembly, the separation assembly is used for receiving the mixture from the collection assembly and separating the mixture, stone coal is discharged from the first discharge port, combustible components are discharged from the second discharge port, an air inlet of the fan is communicated with the separation assembly, the fan is used for generating a negative pressure air flow which drives the mixture to flow in the separation assembly, the negative pressure air flows through the fan and forms a positive pressure air flow at an air outlet of the fan, the air inlet and the air outlet can be communicated with the outside, the mixer is communicated with the second discharge port of the separation assembly and an air outlet of the fan, the mixer is used for receiving the combustible components of the second discharge port, the combustible components are discharged from the second discharge port, an air inlet of the fan is communicated with the separation assembly, and the combustible components are carried by the fan and the air flow is conveyed by the mixer and the positive pressure air flow is recycled by the fan. The material recovery system of the coal mill changes the traditional rough mode of directly blending all stone coal back. Through the combined design of negative pressure separation and positive pressure recovery, the method realizes the effective separation and selective recovery of pebble coal and combustible components (mainly pulverized coal and coal particles) in the mixture discharged from the coal mill for the first time. Only the separated combustible components are sent back to the coal mill, so that the fuel utilization rate is remarkably improved, hard impurities such as ores and gangue in pebble coal are thoroughly prevented from reentering the coal mill, and the cycle of aggravated abrasion and malignant increase of slag discharge amount of equipment is avoided. In some embodiments, the coal pulverizer material recovery system further comprises a first pipeline, an air supplementing pipeline and an air supplementing valve, the sorting assembly further comprises a suction port, the suction port is communicated with the air inlet through the first pipeline, the air supplementing pipeline is communicated with the first pipeline, the air supplementing pipeline is used for being communicated with the outside, and the air supplementing valve is arranged on the air supplementing pipeline. In some embodiments, the coal pulverizer material recovery system further comprises a second pipeline, an exhaust pipeline and an exhaust valve, wherein the second pipeline is communicated with the air outlet of the fan and the mixer, the exhaust pipeline is communicated with the second pipeline, the exhaust pipeline is used for being communicated with the outside, and the exhaust valve is arranged on the exhaust pipeline. In some embodiments, the sorting assembly further comprises a first gathering part, a second gathering part and a gas-solid separator, the first gathering part is