Coal pulverizing system capable of improving coal pulverizing efficiency

Abstract

The invention belongs to the field of metallurgical coal, and relates to a coal pulverizing system capable of improving coal pulverizing efficiency, interconnection and intercommunication of the coal pulverizing systems are indirectly achieved by connecting coal pulverizing system outlet pipelines of the coal pulverizing systems, valves are arranged at multiple positions of the pipelines, and the coal pulverizing efficiency can be improved by switching the on-off states of the different valves according to production requirements. And high-efficiency utilization of the coal grinding system in each coal pulverizing system is realized. When any coal pulverizing system stops production and is overhauled, the corresponding idle coal pulverizing system can be fully utilized to share the coal pulverizing load or provide coal powder for other online running coal pulverizing systems, and the use efficiency of the coal pulverizing systems is effectively improved. And meanwhile, when the coal grinding system of any coal pulverizing system breaks down, the coal grinding systems in other coal pulverizing systems can be effectively replaced, production halt of the coal pulverizing systems is avoided, and finally balanced allocation and efficient utilization of the coal grinding systems in all the coal pulverizing systems are achieved.

Description

Technical Field

[0001] The invention belongs to the field of metallurgical coal and relates to a pulverizing system capable of improving coal grinding efficiency. Background Art

[0002] At present, the ironmaking process in steel enterprises generally has multiple coal powder preparation systems. The main task of the pulverizing system is to grind and dry the raw coal into coal powder with qualified particle size and moisture, and then inject it into the blast furnace through the coal powder injection system. The whole system is fully negative pressure operation, and the suction force is mainly provided by the coal powder fan. The whole pulverizing system is divided into three subsystems, namely the drying gas system, the coal grinding system and the pulverizing system. Among them, the main function of the pulverizing system is to grind the raw coal stored in the coal supply system. After the raw coal enters the pulverizing system from the coal supply system, it is fully contacted with the dry gas entering the pulverizing system, and the two tasks of moisture drying and grinding are completed in the pulverizing system. Since the pulverizing systems in each pulverizing system are independent of each other, there are the following problems in the daily production process: ① When the pulverizing system of a pulverizing system is under maintenance, its corresponding pulverizing system will be forced to idle and cannot share the load of the pulverizing system in other pulverizing systems. In particular, when the quality of raw coal decreases (low grindability, high moisture content, etc.) or other coal grinding systems are not in good working condition, the efficiency of a single pulverizing system in grinding raw coal will be greatly reduced, which will eventually lead to insufficient coal powder supply or substandard quality of ground coal powder, affecting the stable coal injection of blast furnaces and other unfavorable situations. ② When the coal grinding system of a pulverizing system fails and cannot grind coal powder, and the coal grinding systems of other pulverizing systems cannot be replaced, the corresponding pulverizing system will be forced to stop production. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a pulverizing system capable of improving coal grinding efficiency, and to indirectly realize the interconnection of the pulverizing systems by connecting the coal grinding system outlet pipelines of each pulverizing system.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a pulverizing system capable of improving coal grinding efficiency, comprising a hot blast furnace system, a drying gas system, a coal grinding system, and a powder collecting system which are connected in sequence, the hot blast furnace system being used to provide hot air to the blast furnace tuyere and produce hot blast furnace exhaust gas, a coal powder blower being provided at the end of the powder collecting system to provide negative pressure for the entire system, the coal grinding system being connected to a coal supply system to supply raw coal to the pulverizing system, the drying gas system being used to provide the pulverizing system with drying gas required for drying the raw coal, and the powder collecting system being used to collect coal powder ground by the coal grinding system; multiple sets of drying gas systems, coal grinding systems and powder collecting systems are provided, each set of the systems is connected to the hot blast furnace system in parallel, the various systems are connected through connecting pipes, and a valve is provided at the end of the connecting pipe accessing the system.

[0005] Optionally, a chimney is provided between the drying gas system and the hot blast furnace system to discharge surplus hot blast furnace exhaust gas.

[0006] Optionally, the drying gas system includes a drying furnace and a vent valve arranged on the drying furnace, the drying furnace is used to burn blast furnace gas and mix it with blast furnace hot blast furnace exhaust gas to produce mixed flue gas required by the powder making system, when the drying gas system is not in operation, the vent valve releases the residual gas and heat in the drying furnace; an exhaust gas regulating valve and an exhaust gas induced draft fan are also arranged in sequence between the drying furnace and the chimney, the exhaust gas regulating valve adjusts the amount of exhaust gas entering the powder making system according to the production needs of the powder making system, and the exhaust gas induced draft fan is used to introduce blast furnace hot blast furnace exhaust gas into the powder making system; the top of the drying furnace is connected with gas and combustion-supporting air pipelines, the combustion-supporting air pipeline is provided with a combustion-supporting fan and a combustion-supporting air regulating valve, and the gas pipeline is provided with a gas regulating valve.

[0007] Optionally, a hot air valve is provided between the drying furnace and the coal grinding system.

[0008] The beneficial effects of the present invention are as follows: the present invention indirectly realizes the interconnection of the pulverizing systems by connecting the outlet pipelines of the coal grinding systems of each pulverizing system, and valves are arranged at multiple locations on the pipelines. According to production needs, by switching the switch states of different valves, efficient utilization of the coal grinding systems in each pulverizing system is realized. When any pulverizing system is shut down for maintenance, the corresponding idle coal grinding system can be fully utilized to share the coal grinding load or provide coal powder for other online pulverizing systems, effectively improving the utilization efficiency of the coal grinding system. At the same time, it can also ensure that when the coal grinding system of any pulverizing system fails, the coal grinding system in other pulverizing systems can be effectively replaced to avoid shutdown of the pulverizing system, and finally achieve balanced allocation and efficient utilization of the coal grinding systems in all pulverizing systems.

[0009] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0011] Figure 1 It is a schematic diagram of the overall system of the present invention.

[0012] Figure numerals: hot blast furnace system 1, chimney 2, exhaust gas regulating valve 3, exhaust gas induced draft fan 4, dry gas system 5, drying furnace 501, vent valve 502, combustion-supporting fan 503, combustion-supporting air regulating valve 504, gas regulating valve 505, hot blast valve 506, coal grinding system 6, coal supply system 7, powder collection system 8, coal powder fan 9, first valve 10, second valve 11, third valve 12, fourth valve 13, fifth valve 14, sixth valve 15, seventh valve 16, eighth valve 17, ninth valve 18. DETAILED DESCRIPTION

[0013] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0014] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0015] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0016] See also Figure 1, is a pulverizing system capable of improving coal grinding efficiency, comprising a hot blast furnace system 1, a drying gas system 5, a coal grinding system 6, and a powder collecting system 8 which are connected in sequence, the hot blast furnace system 1 is used to provide hot air for the blast furnace tuyere and produce hot blast furnace exhaust gas, a coal powder fan 9 is arranged at the end of the powder collecting system 8 to provide negative pressure for the whole system, the coal grinding system 6 is connected with a coal supply system 7 to supply raw coal to the pulverizing system, the drying gas system 5 is used to provide the pulverizing system with the drying gas required for drying the raw coal, and the powder collecting system 8 is used to collect the coal powder ground by the coal grinding system 6; the drying gas system 5, the coal grinding system 6 and the powder collecting system 8 are provided with multiple sets, each set of the system is connected with the hot blast furnace system 1 in parallel, and each system is connected through a connecting pipe, and a valve is arranged at the end of the connecting pipe access system, a chimney 2 is arranged between the drying gas system 5 and the hot blast furnace system 1 to discharge the surplus hot blast furnace exhaust gas, and the drying gas The system 5 comprises a drying furnace 501 and a vent valve 502 arranged on the drying furnace 501. The drying furnace 501 is used to burn blast furnace gas and mix it with the exhaust gas from the blast furnace hot blast furnace to produce the mixed flue gas required by the powder making system. When the drying gas system 5 is not in operation, the vent valve 502 releases the residual gas and heat in the drying furnace 501. An exhaust gas regulating valve 3 and an exhaust gas induced draft fan 4 are arranged in sequence between the drying furnace 501 and the chimney 2. The exhaust gas regulating valve 3 adjusts the amount of exhaust gas entering the powder making system according to the production needs of the powder making system. The exhaust gas induced draft fan 4 is used to introduce the exhaust gas from the blast furnace hot blast furnace into the powder making system. The top of the drying furnace 501 is connected with a gas and combustion-supporting air pipeline. A combustion-supporting fan 503 and a combustion-supporting air regulating valve 504 are arranged on the combustion-supporting air pipeline. A gas regulating valve 505 is arranged on the gas pipeline. A hot air valve 506 is arranged between the drying furnace 501 and the coal grinding system 6.

[0017] Specific embodiment 1,

[0018] In this embodiment, three systems are provided, namely, system one, system two and system three which are connected in parallel; a second valve 11 is provided between the coal grinding system 6 and the powder collecting system 8 of system one, a sixth valve 15 is provided between the coal grinding system 6 and the powder collecting system 8 of system two, a ninth valve 18 is provided between the coal grinding system 6 and the powder collecting system 8 of system three, and a third valve 12, a fifth valve 14 and an eighth valve 17 which are connected in parallel with the second valve 11, the sixth valve 15 and the ninth valve 18 are provided on the connecting pipelines respectively; a first valve 10, a fourth valve 13 and a seventh valve 16 which are connected with the system one, the system two and the system three are provided on the connecting pipelines between the systems respectively.

[0019] In this embodiment, when any pulverizing system is shut down for maintenance, the corresponding idle coal grinding system 6 is fully utilized to share the coal grinding load or provide coal powder for other online pulverizing systems, thereby effectively improving the utilization efficiency of the coal grinding system 6; at the same time, it is ensured that when the coal grinding system 6 of any pulverizing system fails, the coal grinding system 6 in other pulverizing systems can be effectively replaced to avoid shutdown of the pulverizing system, and ultimately achieve balanced deployment and efficient utilization of the coal grinding systems 6 in all pulverizing systems.

[0020] Normal operation process of the coal grinding system 6 (the coal grinding system 6 that does not replace other pulverizing systems nor share the coal grinding load of other pulverizing systems) (taking one system as an example): close the first valve 10 and the third valve 12, open the second valve 11, and one system uses its own coal grinding system 6 for pulverizing.

[0021] The "one-to-one" operation mode of the coal grinding system 6 (i.e., the coal grinding system 6 of one pulverizing system replaces the coal grinding system 6 of another pulverizing system) (taking one system replacing two systems as an example): close the second valve 11, the third valve 12, the fourth valve 13, the sixth valve 15, the seventh valve 16, and the eighth valve 17, and open the first valve 10 and the fifth valve 14.

[0022] The coal grinding system 6 is in a "one-to-many" operation mode (i.e., the coal grinding system 6 of one pulverizing system shares the coal grinding load of multiple other pulverizing systems at the same time) (taking one system sharing the load of two or three systems at the same time as an example): close the third valve 12, the fourth valve 13, and the seventh valve 16, and open the first valve 10, the fifth valve 14, and the eighth valve 17;

[0023] The "many-to-one" operation mode of the coal grinding system 6 (i.e., the coal grinding systems 6 of multiple pulverizing systems share the coal grinding load of one pulverizing system) (taking two and three systems sharing one system as an example): close the first valve 10, the fifth valve 14, and the eighth valve 17, and open the third valve 12, the fourth valve 13, and the seventh valve 16.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution 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 solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A pulverizing system capable of improving coal grinding efficiency, characterized in that: It includes a hot blast furnace system, a drying gas system, a coal grinding system, and a powder collecting system which are connected in sequence. The hot blast furnace system is used to provide hot air to the blast furnace tuyere and produce hot blast furnace exhaust gas. A coal powder fan is provided at the end of the powder collecting system to provide negative pressure for the entire system. The coal grinding system is connected to a coal supply system to supply raw coal to the pulverizing system. The drying gas system is used to provide the pulverizing system with drying gas required for drying the raw coal. The powder collecting system is used to collect the coal powder ground by the coal grinding system. There are multiple sets of drying gas system, coal grinding system and powder collecting system, each system is connected with the hot air furnace system in parallel, and each system is connected through connecting pipes, and multiple valves are arranged on the connecting pipes.

2. A pulverizing system capable of improving coal grinding efficiency according to claim 1, characterized in that: A chimney is provided between the drying gas system and the hot blast furnace system to discharge the surplus hot blast furnace exhaust gas.

3. A pulverizing system capable of improving coal grinding efficiency according to claim 2, characterized in that: The drying gas system includes a drying furnace and a relief valve arranged on the drying furnace. The drying furnace is used to burn blast furnace gas and mix it with the exhaust gas of the blast furnace hot blast furnace to produce the mixed flue gas required by the powder making system. When the drying gas system is not in operation, the relief valve releases the residual gas and heat in the drying furnace. An exhaust gas regulating valve and an exhaust gas induced draft fan are arranged in sequence between the drying furnace and the chimney. The exhaust gas regulating valve adjusts the amount of exhaust gas entering the powder making system according to the production needs of the powder making system. The exhaust gas induced draft fan is used to introduce the exhaust gas of the blast furnace hot blast furnace into the powder making system. The top of the drying furnace is connected with gas and combustion-supporting air pipelines, the combustion-supporting air pipeline is provided with a combustion-supporting fan and a combustion-supporting air regulating valve, and the gas pipeline is provided with a gas regulating valve.

4. A pulverizing system capable of improving coal grinding efficiency according to claim 3, characterized in that: A hot air valve is installed between the drying furnace and the coal grinding system.

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