CN203540665U - Safe efficient coal powder preparation system - Google Patents
Safe efficient coal powder preparation system Download PDFInfo
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- CN203540665U CN203540665U CN201320486539.3U CN201320486539U CN203540665U CN 203540665 U CN203540665 U CN 203540665U CN 201320486539 U CN201320486539 U CN 201320486539U CN 203540665 U CN203540665 U CN 203540665U
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Abstract
The utility model provides a safe efficient coal powder preparation system which comprises a coal dressing system, a coal grinding system, a separating system and an overheat steam generation system, wherein the coal grinding system is provided with a raw material inlet, an overheat steam inlet, a coal powder outlet and a dust hot steam outlet; an outlet of the coal dressing system is communicated with the raw material inlet of the coal grinding system; an outlet of the overheat steam generation system is communicated with the overheat steam inlet of the coal grinding system; the dust hot steam outlet of the coal grinding system is communicated with an inlet of the separating system; the separating system is provided with a coal powder outlet and a hot steam outlet; the hot steam outlet of the separating system is communicated with a circulating steam inlet of the overheat steam generation system. According to the coal powder preparation system, overheat steam is taken as protection gas, so that the problem of safety in a coal powder preparation process is solved; all overheat steam protection mediums basically can be cyclically utilized, so that the problems of pollutant discharge and heat waste are solved; coal powder is dried by the overheat steam in a coal grinder, so that a drying process is removed, a technological process is simplified, and the raw material processing cost is reduced.
Description
Technical field
The utility model belongs to coal processing field, relates to the pulverized coal preparation technology take feed coal, semicoke or petroleum coke as raw material, relates in particular to one coal dust preparation system safely and efficiently.
Background technology
China is world's first coal power, is also the big country of consumption of coal.It is at the forefront in the world that Chinese coal is verified recoverable reserves, the whole industry year coal mining amount reach nearly 1,000,000,000 tons.China has determined that take coal as main general layout necessary employing is clean, coal processing and utilization mode solves energy problem efficiently.
Pulverized coal preparation is the normal Coal dressing mode adopting of the industries such as electric power, chemical industry, metallurgy, and pulverized coal preparation is generally divided into wet method preparation process and dry preparation process.Wherein to prepare security good for wet method, is widely used in water-coal-slurry preparation technology, but has the problems such as grinding efficiency is low, range of application is narrow, cost of transportation is high; Dry method powder process can be widely used in various industries, has advantages of that grinding efficiency is high, cost of transportation is low, but exist, dust pollution is serious, the easy spontaneous combustion blast of coal dust.
In order to prevent the security hidden trouble in dry method pulverized coal preparation, conventionally take inert gas to protect as nitrogen or flue gas, Fig. 1 is shown in its technological process.Concrete technology is that feed coal utilizes high-temperature flue gas or pre-hot nitrogen to be dried after fragmentation, dried coal grain enters in coal pulverizer and grinds, gas carries part dust and directly discharges, in coal pulverizer, coal grain grinds into coal dust and enters separator, coal dust is as output of products, and gas is directly outer to be arranged or through condenser, remove the follow-up continuous Heating Cyclic of anhydrating and use.The subject matter that this technique exists is: (1) exhaust emissions amount is large, has caused environmental pollution and energy waste; (2) complex procedures, equipment investment cost is higher; (3) coal pulverizer outlet protective gas recycles, and all needs to carry out condensation and removes moisture and reheat intensification, and operating cost is higher, and the internal circulating load of protective gas is below 80%, causes a large amount of energy losses.
Utility model content
The utility model object is to solve prior art defect one coal dust preparation system and method is safely and efficiently provided, and has solved gas discharging in existing dry process coal dust process and has caused serious heat loss and the serious problem of environmental pollution.
For achieving the above object, the utility model is by the following technical solutions:
One is coal dust preparation system safely and efficiently, comprises that Recognition Applied in Coal Preparation System, coal mill system, piece-rate system and superheated steam produce system; Recognition Applied in Coal Preparation System comprises batcher, coal mill system comprises the coal pulverizer that is provided with feed(raw material)inlet, gas access, discharge and gas vent, piece-rate system comprises separator, superheated steam generation system comprises that being provided with steam supplements the heater of entrance, water steam entrance and water steam outlet, described batcher outlet is communicated with coal pulverizer feed(raw material)inlet, the water steam outlet of heater is communicated with coal pulverizer gas access, coal pulverizer gas vent is communicated with separator entrance, and separator gas vent is connected with the water steam entrance of heater.
Described Recognition Applied in Coal Preparation System comprises successively and exports with batcher the disintegrating machine and the separator that are connected, and separator outlet is divided into coarse granule material outlet and fine grained material outlet; Described coal pulverizer comprises coarse granule coal pulverizer and fine grained coal pulverizer; Separator coarse granule material outlet is communicated with coarse granule coal pulverizer feed(raw material)inlet, separator fine grained material outlet is communicated with fine grained coal pulverizer feed(raw material)inlet, coarse granule coal pulverizer gas access is communicated with the water steam outlet of heater, coarse granule coal pulverizer gas vent is communicated with fine grained coal pulverizer gas access, and fine grained coal pulverizer gas vent is communicated with separator entrance.
Described Recognition Applied in Coal Preparation System comprises successively and exports with batcher the disintegrating machine and the separator that are connected, and separator outlet is divided into coarse granule material outlet and fine grained material outlet; Described coal pulverizer comprises coarse granule coal pulverizer and fine grained coal pulverizer; Separator coarse granule material outlet is communicated with coarse granule coal pulverizer feed(raw material)inlet, separator fine grained material outlet is communicated with fine grained coal pulverizer feed(raw material)inlet, coarse granule coal pulverizer and fine grained coal pulverizer gas access are communicated with the water steam outlet of heater respectively, and coarse granule coal pulverizer and fine grained coal pulverizer gas vent are communicated with separator entrance.
Described coal mill system comprises additive adding apparatus, and coarse granule coal pulverizer and fine grained coal pulverizer are equipped with additive entrance, and additive adding apparatus is connected with fine grained coal pulverizer additive entrance with coarse granule coal pulverizer respectively.
Described separator comprises cyclone separator and sack cleaner, cyclone inlet is communicated with coal pulverizer gas vent, the outlet of cyclone separator dusty gas is communicated with sack cleaner entrance, and sack cleaner gas vent is connected with the water steam entrance of heater.
Described superheated steam generation system comprises coal-burning boiler, and the outlet of coal-burning boiler superheated steam is communicated with heater water steam entrance, and the discharge of separator is connected with coal-fired boiler fuel entrance.
The utlity model has following beneficial effect:
The utility model coal pulverizer is connected with superheated vapor generation system, superheated steam passes in coal pulverizer as protective gas, and raw material is heated, not only solved the safety problem in pulverized coal preparation, and superheated steam can realize complete alternation utilization as protective medium, gas need not outer row and condensation process thoroughly solved pollutant emission and heat waste problem; Meanwhile, superheated steam is dried coal dust in coal pulverizer, has saved the drying process of prior art, has not only simplified technological process, and has reduced Raw material processing cost.
Further, also have the following advantages;
(1) different coal grains enter in different coal pulverizers and grind, and have improved coal pulverizer production capacity;
(2) coal dust of the different-grain diameters such as the coal dust made, coal dust is as product or produce the boiler raw material of superheated steam, has realized the clean and effective utilization of coal resources;
(3) the coal dust product of different-grain diameter can utilize separately, also can mix utilization, easily realizes coal powder size grating;
(4) in coal dust, add additive to have certain wetting action to feed coal, can extenuate the problem that coal pulverizer weares and teares, airborne dust is large.
Accompanying drawing explanation
Fig. 1 is the pulverized coal preparation process flow diagram of prior art nitrogen or flue gas protection.
Fig. 2 is the schematic diagram of the utility model coal dust preparation system.
1 - Feeder 2 - Crusher 3 - sorting machine 4 - additive device,5 -1- coarse mill 5-2 - fine particles of coal pulverizer, 6 - cyclone 7 - baghouse, 8 - coal-fired boiler, 9 - heater, 10 - materials, 11 - materials measured after 12 - crushing coal, 13 - 3mm of coal particles larger than 14 - less than 3mm of coal particles 15 - additives 16 - mixed superheated steam, 17 - coarse coal, 18 - level superheated steam, 19 - fine coal, 20 - two of superheated steam, 21 - pulverized powder separator spin after 22 - after the cyclone water vapor, 23 - pulverized coal dust bag after 24 - steam cycle 25 - dust particles, 26 - superheated steam, 27 - supplementary superheated steam, 28 - product superheated steam, 29 - water, A-Separation System , B-coal grinding system, C-separation system, D-superheated steam generation system.
The specific embodiment
Below in conjunction with accompanying drawing, the utility model is described in detail:
As shown in Figure 1, the utility model comprises 4 systems, and A is Recognition Applied in Coal Preparation System, and B is coal mill system, and C is piece-rate system, and D is that superheated steam produces system.Recognition Applied in Coal Preparation System A comprises batcher 1, disintegrating machine 2 and separator 3; Coal mill system B comprises additive adding apparatus 4, coarse granule coal pulverizer 5-1 and fine grained coal pulverizer 5-2; Piece-rate system C comprises cyclone separator 6 and sack cleaner 7; Superheated steam produces system D and comprises coal-burning boiler 8 and heater 9.
In Recognition Applied in Coal Preparation System A, batcher 1 outlet is connected with disintegrating machine 2 entrances, and disintegrating machine 2 outlets are connected with separator 3 entrances.In coal mill system B, additive adding apparatus 4 exports respectively and is connected with the additive entrance of fine grained coal pulverizer 5-2 with coarse granule coal pulverizer 5-1, coarse granule coal pulverizer 5-1 has two outlets, wherein 18 outlets of one-level superheated steam are connected with fine grained coal pulverizer 5-2 entrance, and coarse granule coal pulverizer 5-1 outlet at bottom is directly discharged rough coal powder 17; Fine grained coal pulverizer 5-2 is provided with two outlets, and wherein outlet at bottom is directly discharged fine breeze 19, and another outlet is secondary superheated steam 20.In piece-rate system C, cyclone separator 6 outlet at bottoms separate rear coal dust 21 for revolving powder, and top exit is connected with sack cleaner 7 entrances, and the top exit of sack cleaner 7 is recirculated water steam 24, and outlet at bottom is the coal dust 23 after bag-type dust.Superheated steam produces in system D; coal-burning boiler 8 outlets are superheated steam 26; in superheated steam 26, extract part and supplement superheated steam 27 as protective medium, all the other are directly exported as product superheated steam 28, and heater 9 entrances are connected with supplementary superheated steam 27 pipelines.
Separator 3 in Recognition Applied in Coal Preparation System A has two outlets, and wherein separator 3 is greater than the outlet of 3mm coal grain 13 and is connected with coarse granule coal pulverizer 5-1 feed(raw material)inlet in coal mill system B; Coal grain 14 outlets that are less than or equal to 3mm are connected with fine grained coal pulverizer 5-2 feed(raw material)inlet in coal mill system B.In coal mill system B, mixing superheated steam 16 entrances of coarse granule coal pulverizer 5-1 are connected with heater 9 outlets in superheated steam generation system D; In coal mill system B, 20 outlets of fine grained coal pulverizer 5-2 secondary superheated steam are connected with cyclone separator 6 entrances in piece-rate system C.Coal Dust 25 after coal dust 21 in piece-rate system C after cyclonic separation merges with the coal dust after bag-type dust 23 is connected with coal-burning boiler 8 fuel inlets that superheated steam produces in system D; Recirculated water steam 24 in piece-rate system C produces heater 9 entrances in system D with superheated steam and is connected.
The utility model pulverized coal preparation method is specific as follows:
First raw material 10 enters in batcher 1, and raw material can be coal or semicoke or petroleum coke, through batcher 1, is delivered to disintegrating machine 2, and raw material is sent to separator 3 be broken into granule in disintegrating machine 2 after; By the coal grain of different-grain diameter separately, the coal grain 13 that is wherein greater than 3mm is sent in coarse granule coal pulverizer 5-1 separator 3, and the coal grain 14 that is less than or equal to 3mm is sent in fine grained coal pulverizer 5-2;
In coarse granule coal pulverizer 5-1, by additive feeding device 4, add the additive 15 of mass ratio 0-5%, and pass into mix superheated steam 16, superheated steam not only can be dried raw coal, and can protect the coal-grinding security of coarse granule coal pulverizer, pulverized coal particle particle diameter after coarse granule coal pulverizer 5-1 grinds is 20-300 μ m, coarse granule coal pulverizer 5-1 has two outlets, the wherein direct output products rough coal of outlet at bottom powder 17, the one-level superheated steam 18 of another outlet is sent in fine grained coal pulverizer 5-2, for the security of dry coal dust and protection fine grained coal pulverizer coal-grinding; In fine grained coal pulverizer 5-2, by additive feeding device 4, add the additive 15 of mass ratio 0-5%, fine grained coal pulverizer 5-2 has two outlets, wherein outlet at bottom is directly produced product fine breeze, and the secondary superheated steam 20 of another outlet is sent in cyclone separator 6; Through cyclone separator 6, coal dust and gas are carried out to initial gross separation, the coal dust 21 after the cyclonic separation of the outlet at bottom after separation, top exit is the steam 22 after cyclonic separation;
Be below the specific embodiment of the utility model pulverized coal preparation method:
By granularity, be that 0-200mm raw material is sent in disintegrating machine broken after batcher metering, raw material can be bituminous coal or semicoke or petroleum coke, coal grain after fragmentation carries out sorting through separator, the coal grain that is wherein greater than 3mm is sent in rod mill, the coal grain that is less than or equal to 3mm is sent in ball mill, in rod mill, pass into superheated steam protection system safety, superheat steam temperature 240-350 ℃, pressure 0.1-0.3MPa, additive 1%(wt%) adds in ball mill with dry powder or vaporific form, additive can be alkylbenzenesulfonate, alkylsulfonate, one or more in alkylnaphthalene sulfonate and lignosulfonates, rough coal powder after rod mill grinds is directly discharged as product, coarse grained particle size distribution is 30-300 μ m, wherein the particle of <75 μ m accounts for more than 50%, the one-level superheated steam outlet of rod mill is directly connected with ball mill entrance, play the effect of protection system safety, additive 1%(wt%) adds in ball mill with dry powder or vaporific form, additive can be alkylbenzenesulfonate, alkylsulfonate, one or more in alkylnaphthalene sulfonate and lignosulfonates, product fine breeze is directly discharged in ball mill bottom, fine breeze granularity <45 μ m, wherein the particle of <20 μ m accounts for more than 40%, the secondary superheated steam of ball mill is successively through cyclone separator, sack cleaner is separation with superheated steam by coal dust, coal dust after coal dust and bag-type dust after cyclonic separation is produced superheated steam as boiler raw material, part superheated steam superheated steam as a supplement wherein, all the other are directly exported as product, recirculated water steam after bag-type dust and supplementary superheated steam mix to heat up and are converted into qualified superheated steam and continue to recycle in heater, rough coal powder in technique and fine breeze product can be directly used in water-coal-slurry processed or burning or gasification or iron-smelting process or materials processing, also can packed and transported, superheated steam product can be used as heat transferring medium, heating source or for steam turbine power generation.
By the rough coal powder in embodiment 1 and the fine breeze ratio of 9:1-1:9 in mass ratio, by grain size distribution, prepare high-concentration coal-water slurry, first taking rough coal powder in embodiment 1 slowly adds water and is uniformly mixed and obtain the primary water coal slurry that concentration is 50%-65%, next fine breeze taking in embodiment 1 adds in above-mentioned primary water coal slurry, through high-speed stirred, mix, obtain the high-concentration coal-water slurry product of 60%-85%.
In the utility model for high ash content and/high-sulfur raw material, at separator, can suitably add certain deliming agent or desulfurizing agent to carry out deliming and desulfurization processing.One or more coal pulverizers can be set in the utility model as required in coal mill system B, and coarse granule coal pulverizer and fine grained coal pulverizer can parallel connection or serial operations; The additive adding in coarse granule coal pulverizer and fine grained coal pulverizer in the utility model can be the same or different.
In coal pulverizer in the utility model coal mill system B, pass into superheated steam and additive can improve coal dust surface property, reduce the diffusion of coal pulverizer wearing and tearing and airborne dust, also can not doping in Mill Systems for grinding the raw coal that index is higher.
Claims (6)
1. a coal dust preparation system safely and efficiently, is characterized in that: comprise that Recognition Applied in Coal Preparation System (A), coal mill system (B), piece-rate system (C) and superheated steam produce system (D), Recognition Applied in Coal Preparation System (A) comprises batcher (1), coal mill system (B) comprises coal pulverizer, piece-rate system (C) comprises separator, superheated steam produces system (D) and comprises that being provided with steam supplements entrance, the heater (9) of water steam entrance and water steam outlet, described batcher (1) outlet is communicated with coal pulverizer feed(raw material)inlet, coal pulverizer is provided with gas access and gas vent, the water steam outlet of heater (9) is communicated with coal pulverizer gas access, coal pulverizer gas vent is communicated with separator entrance, separator gas vent is connected with the water steam entrance of heater (9).
2. coal dust preparation system safely and efficiently according to claim 1, it is characterized in that: described Recognition Applied in Coal Preparation System (A) comprises successively and export with batcher (1) disintegrating machine (2) and the separator (3) that are connected, separator (3) outlet is divided into coarse granule material outlet and fine grained material outlet; Described coal pulverizer comprises coarse granule coal pulverizer (5-1) and fine grained coal pulverizer (5-2); Separator (3) coarse granule material outlet is communicated with coarse granule coal pulverizer (5-1) feed(raw material)inlet, separator (3) fine grained material outlet is communicated with fine grained coal pulverizer (5-2) feed(raw material)inlet, coarse granule coal pulverizer (5-1) gas access is communicated with the water steam outlet of heater (9), coarse granule coal pulverizer (5-1) gas vent is communicated with fine grained coal pulverizer (5-2) gas access, and fine grained coal pulverizer (5-2) gas vent is communicated with separator entrance.
3. coal dust preparation system safely and efficiently according to claim 1, it is characterized in that: described Recognition Applied in Coal Preparation System (A) comprises successively and export with batcher (1) disintegrating machine (2) and the separator (3) that are connected, separator (3) outlet is divided into coarse granule material outlet and fine grained material outlet; Described coal pulverizer comprises coarse granule coal pulverizer (5-1) and fine grained coal pulverizer (5-2); Separator (3) coarse granule material outlet is communicated with coarse granule coal pulverizer (5-1) feed(raw material)inlet, separator (3) fine grained material outlet is communicated with fine grained coal pulverizer (5-2) feed(raw material)inlet, coarse granule coal pulverizer (5-1) and fine grained coal pulverizer (5-2) gas access are communicated with the water steam outlet of heater (9) respectively, and coarse granule coal pulverizer (5-1) and fine grained coal pulverizer (5-2) gas vent are communicated with separator entrance.
4. according to the coal dust preparation system safely and efficiently described in claim 2 or 3, it is characterized in that: described coal mill system comprises additive adding apparatus (4), coarse granule coal pulverizer (5-1) and fine grained coal pulverizer (5-2) are equipped with additive entrance, and additive adding apparatus (4) is connected with fine grained coal pulverizer (5-2) additive entrance with coarse granule coal pulverizer (5-1) respectively.
5. coal dust preparation system safely and efficiently according to claim 4, it is characterized in that: described separator comprises cyclone separator (6) and sack cleaner (7), cyclone separator (6) entrance is communicated with coal pulverizer gas vent, the outlet of cyclone separator (6) dusty gas is communicated with sack cleaner (7) entrance, and sack cleaner (7) gas vent is connected with the water steam entrance of heater (9).
6. coal dust preparation system safely and efficiently according to claim 4, it is characterized in that: described superheated steam generation system comprises coal-burning boiler (8), the outlet of coal-burning boiler (8) superheated steam is communicated with heater (9) water steam entrance, and the discharge of separator is connected with coal-burning boiler (8) fuel inlet.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320486539.3U CN203540665U (en) | 2013-08-09 | 2013-08-09 | Safe efficient coal powder preparation system |
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| CN201320486539.3U CN203540665U (en) | 2013-08-09 | 2013-08-09 | Safe efficient coal powder preparation system |
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| CN203540665U true CN203540665U (en) | 2014-04-16 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103447137A (en) * | 2013-08-09 | 2013-12-18 | 陕西煤业化工技术研究院有限责任公司 | Safe and efficient system and safe and efficient method for preparing powdered coal |
| CN114308274A (en) * | 2021-11-08 | 2022-04-12 | 广西投资集团北海发电有限公司 | Safe operation method for BBD4060 double-inlet and double-outlet direct-blowing type steel ball-milling lignite |
-
2013
- 2013-08-09 CN CN201320486539.3U patent/CN203540665U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103447137A (en) * | 2013-08-09 | 2013-12-18 | 陕西煤业化工技术研究院有限责任公司 | Safe and efficient system and safe and efficient method for preparing powdered coal |
| CN114308274A (en) * | 2021-11-08 | 2022-04-12 | 广西投资集团北海发电有限公司 | Safe operation method for BBD4060 double-inlet and double-outlet direct-blowing type steel ball-milling lignite |
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