CN106010607A - Coal pyrolysis and gasification coupling technology and device - Google Patents

Abstract

The invention provides a coal pyrolysis and gasification coupling technology and device. According to the technology, hot coal gas generated through coal gasification makes direct contact with dry coal, and the dry coal is subjected to dry distillation with the high-temperature sensible heat of the hot coal gas so that on one hand, the high-temperature sensible heat of the hot coal gas can be fully utilized, the heat exchange efficiency can be improved, and thus the energy consumption of the whole technology can be greatly reduced; on the other head, due to the fact that hydrogen in the gasified hot coal gas is high in content and concentration, the yield of tar can be increased through the hydrogen-rice atmosphere; furthermore, only large particle size raw coal is subjected to dry distillation, and thus the quality of the tar is improved; besides, in the technology, raw material coal is screened to be divided into small particle size pulverized coal and large particle size raw coal, and then gasification and dry distillation treatment are carried out on the pulverized coal and the raw coal respectively, so that the raw material coal within the full particle size range can be treated with the technology, and full particle size feeding of the raw material coal is achieved. According to the device, a purification device for the hot coal gas does not need to be independently arranged, and thus the energy consumption of the system can be easily reduced.

Description

A kind of coal pyrolytic gasified coupling technique and device

Technical field

The present invention relates to technical field of coal chemical industry, particularly relate to the coupling technique of a kind of pyrolysis of coal and gasification And device.

Background technology

China is an oil starvation few gas, the country of coal resources relative abundance, and coal occupies primary energy More than 65%, the coal production of current China and the total quantity consumed Jun Lie world are the first, and coal production Still in ascendant trend year by year.But, having more than half in the existing coal resources of China is low-order coal, Owing to low-order coal is generally of the features such as elevated oxygen level, high-moisture, poor stability and calorific value are low, thus It is difficult to as large-scale industrial gasification raw material, is more the power fuel being solely for some areas, But the discharge of the produced a large amount of pollutant of low-order coal burning, causes present stage China to be faced with the energy Supply security and the dual-pressure of environmental conservation, therefore, research and development clean coal technology is very urgent.

Up to now, the high effect cleaning transformation technology of low-order coal is the core of clean coal technology, also will It it is following developing direction.Low-order coal changed into the semicoke of high heating value by pyrolysis, obtains heat simultaneously The improving quality of coal by pyrolysis technique solving coal gas and tar is to realize the effective way that low-order coal cleaning converts, but mesh Front the most not mature enough to the research majority of low order improving quality of coal by pyrolysis technology, still it is in test or shows Model stage, such as Chinese patent literature CN104762097A disclose a kind of low order pulverized coal pyrolysis upgrading Method, the raw material fine coal of granularity≤30mm is sent in the rotary drying stove of band dedusting function by the method, The coal dust of granularity ＜ 0.5mm, granularity in fine coal is removed in the lump while to raw material fine coal heat drying Moisture-free coal for 0.5-30mm occurs pyrolytic reaction to generate upgraded coal and height in external-heating revolving pyrolysis oven Temperature oil gas, high-temperature oil gas obtains pyrolyzing coal air and heat Xie Shui and coal tar after gas recovery system for oil processes, Wherein pyrolysis coal gas is back to turn round in pyrolysis oven after being heated to 150-450 DEG C；Rotary drying fire grate goes out The separated coal dust of dry gas, lowered temperature reclamation be dried water etc. process after, the most pressurized, heat up and return To rotary drying stove；The coal dust of granularity ＜ 0.5mm enters gas generating system after supplementing fine coal and turns Chemical conversion fuel gas, then produce 800-1000 DEG C of flue gas through air stove, as external-heating revolving pyrolysis oven Thermal source.

Raw material fine coal, by using the rotary drying stove of band dedusting function, is being dried by above-mentioned technology While can remove the coal dust of granularity ＜ 0.5mm in fine coal such that it is able to reduce enter pyrolysis oven coal The amount of dirt, so that the coal powder content in coai-tar product is few, improves the quality of coal tar.But This technology yet suffers from following deficiency: one, can only process the fine coal of granularity≤30mm, and cannot be real The wholegrain footpath charging of existing feed coal so that above-mentioned method for upgrading has significant limitation；Its two, right For the fine coal of granularity≤30mm, the coal dust of granularity ＜ 0.5mm accounts for 3～15%, these coal dust gas The heat of coal gas produced by changing not be enough to the moisture-free coal pyrolysis making granularity be 0.5-30mm, thus Also need to make it be converted into high-temperature flue gas gasification gas burning, recycle this high-temperature flue gas as external-heat The thermal source of pyrolysis oven, it is seen that above-mentioned technology can not directly utilize the high temperature sensible heat of gasification gas, also exists The defect that heat exchange efficiency is poor, efficiency is low；Its three, owing to pyrolysis coal gas originally be exactly from pyrolysis oven discharge , thus this process that pyrolysis coal gas is recycled to pyrolysis oven again can't significantly change in pyrolysis oven Density of hydrogen, the coal tar yield of institute's method described above is difficult to improve.In consideration of it, how to existing Pyrolysis of coal improves to overcome above-mentioned deficiency, for those skilled in the art with the coupling technique of gasification For remain a technical barrier urgently to be resolved hurrily.

Summary of the invention

Present invention solves the technical problem that and be to overcome existing for existing coal pyrolytic gasified coupling technique Energy consumption is high, coal tar yield is low and poor quality, the defect of wholegrain degree feed coal of cannot being applicable to, and then There is provided that a kind of energy consumption is little, coal tar yield high and quality better, the coal of feed coal wholegrain footpath charging can be realized Pyrolytic gasification coupling technique and device.

To this end, the technical scheme that the present invention realizes above-mentioned purpose is:

A kind of coal pyrolytic gasified coupling technique, comprises the steps:

(1) feed coal is sieved, obtain granularity<fine coal of 6mm and the raw coal of granularity>=6mm；

(2) by described granularity, < coal gasification of 6mm forms heating gas, after described heating gas removing dust It is purified coal gas；

(3) raw coal to described granularity >=6mm is dried and processes to obtain moisture-free coal, described moisture-free coal with Purification coal gas in step (2) directly contacts to utilize described purification coal gas to do described moisture-free coal Evaporate process, produce semicoke and pyrolysis gas.

The heat smoke of 150～350 DEG C is used to drop as the thermal source of dry link, dried flue gas removing dust Temperature processes, and is purified cooled flue gas and coal dust；

Step (2) also obtain coal dust while obtaining described purification coal gas.

Gasifying described coal dust to produce heating gas, described heating gas is used as the thermal source of dry distilling link.

Described purification cooled flue gas and the semicoke generation heat exchange in step (3), with by described semicoke Temperature is reduced to less than 100 DEG C and obtains heat smoke, and described heat smoke is recycled to described dry link In.

Described pyrolysis gas is carried out cooling and purifying process, obtains tar, cooled coal gas and coke breeze.

Described cooled coal gas is back to after the flue gas that burning produces mixes with the heat smoke in heat exchange link In described dry link.

By described coke breeze gasification to produce heating gas, as the thermal source of described dry distilling link.

A kind of coal pyrolytic gasified coupling device, including:

Screening plant, its be provided with the first outlet and second outlet, described first outlet be used for discharging grain <fine coal of 6mm, described second outlet is for discharging the raw coal of granularity>=6mm for degree；

Gasification furnace, its import is connected setting, the outlet of described gasification furnace and high temperature with described first outlet Dust arrester is connected；

Fixed-bed pyrolysis stove, it is internally provided with dryer section, retort section and the cooling section being sequentially communicated, Described dryer section is connected setting, described retort section and described high-temperature dust removing device with described second outlet Gas outlet is connected, and is additionally provided with pyrolysis gas outlet and semicoke outlet in described retort section.

Described dryer section is provided with gas approach and exhanst gas outlet, is connected setting with described exhanst gas outlet Dedusting heat sink, the gas outlet of described dedusting heat sink is had to be connected with described cooling section；

Described cooling section is additionally provided with heat smoke outlet, the outlet of described heat smoke and the cigarette of described dryer section Gas import is connected.

Being provided with and communicated with cooling purifying device with described pyrolysis gas outlet, described cooling purifying device is arranged There are the outlet of tar outlet, cooled coal gas and coke breeze outlet；

The outlet of described coke breeze, the coal dust outlet of described high-temperature dust removing device and described dedusting heat sink Coal dust outlet import with described gasification furnace respectively is connected；

It is connected with burner, the gas outlet of described burner and institute with the outlet of described cooled coal gas State heat smoke outlet to be connected.

The technique scheme of the present invention has the advantage that

1, coal pyrolytic gasified coupling technique of the present invention, utilizes produced by coal gasification initiatively Heating gas is as the thermal source of dry distilling link, by directly being contacted with moisture-free coal by heating gas, to utilize heat The high temperature sensible heat of coal gas carries out dry distilling process to moisture-free coal so that moisture-free coal occur pyrolysis produce semicoke and Pyrolysis gas.With the thermal source that the heating gas produced flue gas of burning is used as external-heat pyrolysis oven by prior art Comparing, the technique of the present invention uses the mode that heating gas directly contacts with moisture-free coal, on the one hand can be abundant Utilize the high temperature sensible heat of heating gas, be simultaneously also beneficial to improve heat exchange efficiency, thus significantly reduce whole The energy consumption of individual technique, the energy consumption of technique of the present invention compared with prior art can decline 10%；Another Aspect is owing to the hydrogen content in heat of gasification coal gas is high, concentration is big, and this hydrogen-rich atmosphere may advantageously facilitate Tar release in retort process, thus it is remarkably improved the yield of tar, compared with prior art, The productivity that the technique of the present invention is coal-tar middle oil adds about 10%.The present invention is only to granularity >=6mm in addition Raw coal carry out dry distilling process, thus decrease the coal dust content in raw coal so that in retorted product Dust Capacity falls sharply, and thus also improves the quality of tar.

Further, the technique of the present invention by feed coal screening be classified as granularity < fine coal of 6mm and The raw coal of granularity >=6mm, more above-mentioned fine coal and raw coal are gasified respectively and dry distilling process, thus make The technique obtaining the present invention can process the feed coal of full particle size range, can only process granularity with prior art Fine coal at below 30mm is compared, and the technique of the present invention achieves the wholegrain footpath charging of feed coal, because of And it is very suitable for large-scale promotion and application.

2, coal pyrolytic gasified coupling technique of the present invention, is dried the raw coal of granularity >=6mm Process, through dedusting cooling, the purification cooled flue gas formed after row outside the heat smoke used during process can use In cooling semicoke, thus obtained heat smoke may return to be dried link as dry thermal source so that The technique of the present invention is capable of being dried, cooling down the flue gas recirculation of link and utilizes, thus reduces further The system energy consumption of whole technique.

3, coal pyrolytic gasified coupling technique of the present invention, also can be to the dedusting isolated coal of link Dirt and the pyrolysis gas isolated coke breeze of purge segment carry out gasification process, technique itself to be produced Raw garbage recycling and be converted into heating gas, not only solve coal dust and coke breeze be difficult by asks Topic, it is often more important that farthest reduce system energy consumption so that the technique efficiency of the present invention reaches The highest.

4, coal pyrolytic gasified coupling device of the present invention, by removing the outlet of gasification furnace with high temperature Dirt device is connected, then the gas outlet of high-temperature dust removing device is connected setting with retort section, so Just can be directly entered retort section after the heating gas removing dust of autopneumatolysis stove, and finally enter together with pyrolysis gas Enter cooling purifying device, so that the coupling device of the present invention need not be separately provided the purification of heating gas Device, thus save equipment investment and floor space, reduce system energy consumption.

Accompanying drawing explanation

In order to be illustrated more clearly that the specific embodiment of the invention or technical scheme of the prior art, under The accompanying drawing used required in detailed description of the invention or description of the prior art will be briefly described by face, It should be evident that the accompanying drawing in describing below is some embodiments of the present invention, general for this area From the point of view of logical technical staff, on the premise of not paying creative work, it is also possible to obtain according to these accompanying drawings Obtain other accompanying drawing.

Fig. 1 is the process chart of coal pyrolytic gasified coupling technique of the present invention；

Fig. 2 is the structural representation of coal pyrolytic gasified coupling device of the present invention；

Wherein, reference is as follows:

1-screening plant；2-gasification furnace；3-high-temperature dust removing device；4-fixed-bed pyrolysis stove；41-dryer section； 42-retort section；43-cooling section；5-dedusting heat sink；6-cooling purifying device.

Detailed description of the invention

Below in conjunction with accompanying drawing, technical scheme is clearly and completely described, it is clear that Described embodiment is a part of embodiment of the present invention rather than whole embodiments.Based on this Embodiment in bright, those of ordinary skill in the art are obtained under not making creative work premise Every other embodiment, broadly fall into the scope of protection of the invention.

In describing the invention, unless otherwise clearly defined and limited, term " be connected ", " connection " Should be interpreted broadly, connect for example, it may be fixing, it is also possible to be to removably connect, or integratedly Connect；Can be to be joined directly together, or be indirectly connected to by intermediary, it is also possible in being two elements The connection in portion.For the ordinary skill in the art, above-mentioned term can be understood with concrete condition Concrete meaning in the present invention.Additionally, it is involved in invention described below difference embodiment As long as and technical characteristic each other do not constitute conflict just can be combined with each other.

Embodiment 1

As it is shown in figure 1, the coal pyrolytic gasified coupling technique described in the present embodiment, comprise the steps:

Feed coal is sieved, is divided into granularity<fine coal of 6mm and the raw coal of granularity>=6mm； Wherein:

< fine coal of 6mm enters in gasification furnace generating gasification under the effect of gasifying agent to described granularity, obtains Heating gas, is purified coal gas after described heating gas removing dust, in the present embodiment, and described gasification furnace For circle fluidized-bed gasification furnace, gasifying agent used is air, the most also can root According to needing the gaseous mixture selecting to use oxygen rich gas, oxygen or oxygen and steam as gasifying agent；

The raw coal of described granularity >=6mm enters in fixed-bed pyrolysis stove, being dried at fixed-bed pyrolysis stove Section, uses the heat smoke of 150～350 DEG C that described raw coal is dried process, obtains moisture-free coal and contain Water vapour and the dried flue gas of a small amount of coal dust；Dried flue gas removing dust cooling processes, and separates It is purified cooled flue gas and coal dust；Described moisture-free coal then enters the retort section of fixed-bed pyrolysis stove, Directly contact with the purification coal gas from gasification furnace, utilize the high temperature sensible heat purifying coal gas to be dried described Coal carries out dry distilling process so that moisture-free coal is pyrolyzed, and produces semicoke and pyrolysis gas, described pyrolysis gas warp Cooling and purifying processes and obtains tar, cooled coal gas and coke breeze, described semicoke with from dryer section described only Change cooled flue gas generation heat exchange, be reduced to less than 100 DEG C using the temperature by described semicoke and produce as semicoke Product discharge pyrolysis oven, and the heat smoke of about 250 DEG C is also obtained simultaneously.

Coal pyrolytic gasified coupling technique described in the present embodiment, utilizes produced by coal gasification initiatively Heating gas is as the thermal source of dry distilling link, by directly being contacted with moisture-free coal by heating gas, to utilize heat The high temperature sensible heat of coal gas carries out dry distilling process to moisture-free coal so that moisture-free coal occur pyrolysis produce semicoke and Pyrolysis gas.With the thermal source that the heating gas produced flue gas of burning is used as external-heat pyrolysis oven by prior art Comparing, the technique of the present embodiment uses the mode that heating gas directly contacts with moisture-free coal, on the one hand can fill Divide the high temperature sensible heat utilizing heating gas, be simultaneously also beneficial to improve heat exchange efficiency, thus significantly reduce The energy consumption of whole technique, the energy consumption of technique described in the present embodiment compared with prior art can decline 10%； On the other hand owing to the hydrogen content in heat of gasification coal gas is high, concentration is big, this hydrogen-rich atmosphere is conducive to Promote tar release in retort process, thus be remarkably improved the yield of tar, with prior art Comparing, the productivity that the technique of the present embodiment is coal-tar middle oil adds about 10%.The present embodiment is only in addition The raw coal of granularity >=6mm is carried out dry distilling process, thus decreases the coal dust content in raw coal so that be dry The Dust Capacity evaporated in product falls sharply, and thus also improves the quality of tar.Further, the work of the present embodiment Skill by feed coal screening be classified as granularity<fine coal of 6mm and the raw coal of granularity>=6mm, then Above-mentioned fine coal and raw coal are gasified respectively and dry distilling processes, so that the technique energy of the present embodiment Enough process the feed coal of full particle size range, the granularity powder at below 30mm can only be processed with prior art Coal facies ratio, the technique of the present embodiment achieves the wholegrain footpath charging of feed coal, thus is very suitable for advising greatly Mould is promoted and application.

For reducing the system energy consumption of whole technique as much as possible, as preferred embodiment, can be by solid The heat smoke that the cooling section of fixed bed pyrolysis oven produces is fed through dryer section, it is possible to burnt by above-mentioned cooled coal gas To produce high-temperature flue gas, then it is mixed after 350 DEG C entrance dryer section as dry link with heat smoke Circulation thermal source；Meanwhile, also the dedusting link isolated coal dust of institute and pyrolysis gas can be purified The isolated coke breeze of link institute is sent in gasification furnace and is carried out gasification process, so that technique itself is produced Garbage recycling and be converted into heating gas, not only solve coal dust and problem that coke breeze is difficult by, The more important thing is and farthest reduce system energy consumption so that the technique efficiency of the present invention reaches the highest.

Embodiment 2

As in figure 2 it is shown, the coal pyrolytic gasified coupling device described in the present embodiment includes:

Screening plant 1, its be provided with the first outlet and second outlet, described first outlet be used for discharging grain <fine coal of 6mm, described second outlet is for discharging the raw coal of granularity>=6mm for degree；

Gasification furnace 2, its import is connected setting with described first outlet, and the outlet of described gasification furnace 2 is with high Temperature dust arrester 3 is connected；

Fixed-bed pyrolysis stove 4, it is internally provided with dryer section 41, the retort section 42 and cold being sequentially communicated But section 43, described dryer section 41 is connected setting with described second outlet, and described retort section 42 is with described The gas outlet of high-temperature dust removing device 3 is connected, and is additionally provided with pyrolysis gas outlet in described retort section 42 Export with semicoke.

Coal pyrolytic gasified coupling device described in the present embodiment, by removing the outlet of gasification furnace with high temperature Dirt device is connected, then the gas outlet of high-temperature dust removing device is connected setting with retort section, so Just can be directly entered retort section after the heating gas removing dust of autopneumatolysis stove, and finally enter together with pyrolysis gas Enter cooling purifying device, so that the coupling device in the present embodiment need not be separately provided heating gas Purifier, thus save equipment investment and floor space, reduce system energy consumption.

As selectable embodiment, for reducing the system energy consumption of whole device as much as possible, at this In embodiment, described dryer section 41 is provided with gas approach and exhanst gas outlet, with described exhanst gas outlet even Connect and be provided with dedusting heat sink 5, the gas outlet of described dedusting heat sink 5 and described cooling section 43 are connected；Described cooling section 43 is additionally provided with heat smoke outlet, and the outlet of described heat smoke is dry with described The gas approach of dry section 41 is connected；It is provided with and communicated with cooling purifying device 6 with described pyrolysis gas outlet, Described cooling purifying device 6 is provided with tar outlet, cooled coal gas outlet and coke breeze outlet；Described coke breeze Outlet, the coal dust outlet of described high-temperature dust removing device 3 and the coal dust outlet of described dedusting heat sink 5 Import with described gasification furnace 2 is connected respectively；It is connected with burning dress with the outlet of described cooled coal gas Putting (not shown in Fig. 2), the gas outlet of described burner is connected with the outlet of described heat smoke.

Obviously, above-described embodiment is only for clearly demonstrating example, and not to embodiment party The restriction of formula.For those of ordinary skill in the field, the most also may be used To make other changes in different forms.Here without also all of embodiment being given With exhaustive.And the obvious change thus extended out or variation are still in the guarantor of the invention Protect among scope.

Claims (10)

1. a coal pyrolytic gasified coupling technique, comprises the steps:

(1) feed coal is sieved, obtain granularity<fine coal of 6mm and the raw coal of granularity>=6mm；

(2) by described granularity, < coal gasification of 6mm forms heating gas, after described heating gas removing dust It is purified coal gas；

(3) raw coal to described granularity >=6mm is dried and processes to obtain moisture-free coal, described moisture-free coal with Purification coal gas in step (2) directly contacts to utilize described purification coal gas to do described moisture-free coal Evaporate process, produce semicoke and pyrolysis gas.

Coal pyrolytic gasified coupling technique the most according to claim 1, it is characterised in that use The heat smoke of 150～350 DEG C processes as the thermal source of dry link, dried flue gas removing dust cooling, It is purified cooled flue gas and coal dust；

Step (2) also obtain coal dust while obtaining described purification coal gas.

Coal pyrolytic gasified coupling technique the most according to claim 2, it is characterised in that by described coal Dust and gas is to produce heating gas, and described heating gas is used as the thermal source of dry distilling link.

4. according to the coal pyrolytic gasified coupling technique described in Claims 2 or 3, it is characterised in that described Purify cooled flue gas and the semicoke generation heat exchange in step (3), the temperature of described semicoke to be reduced To less than 100 DEG C and obtain heat smoke, described heat smoke is recycled in described dry link.

5. according to the coal pyrolytic gasified coupling technique described in any one of claim 1-4, it is characterised in that Described pyrolysis gas is carried out cooling and purifying process, obtains tar, cooled coal gas and coke breeze.

Coal pyrolytic gasified coupling technique the most according to claim 5, it is characterised in that described cold coal Gas is back to described dry link after the flue gas that burning produces mixes with the heat smoke in heat exchange link In.

7. according to the coal pyrolytic gasified coupling technique described in claim 5 or 6, it is characterised in that by institute State coke breeze gasification to produce heating gas, as the thermal source of described dry distilling link.

8. a coal pyrolytic gasified coupling device, including:

Screening plant (1), its be provided with the first outlet and second outlet, described first outlet be used for arranging <fine coal of 6mm, described second outlet is for discharging the raw coal of granularity>=6mm to go out granularity；

Gasification furnace (2), its import is connected setting, going out of described gasification furnace (2) with described first outlet Mouth is connected with high-temperature dust removing device (3)；

Fixed-bed pyrolysis stove (4), it is internally provided with dryer section (41), the retort section (42) being sequentially communicated With cooling section (43), described dryer section (41) is connected setting, described retort section with described second outlet (42) gas outlet with described high-temperature dust removing device (3) is connected, in described retort section (42) It is additionally provided with pyrolysis gas outlet and semicoke outlet.

Coal pyrolytic gasified coupling device the most according to claim 8, it is characterised in that described dry Dry section (41) are provided with gas approach and exhanst gas outlet, are connected with dedusting with described exhanst gas outlet Heat sink (5), the gas outlet of described dedusting heat sink (5) and described cooling section (43) phase Connection；

Described cooling section (43) is additionally provided with heat smoke outlet, and the outlet of described heat smoke is dried with described The gas approach of section (41) is connected.

Coal pyrolytic gasified coupling device the most according to claim 8 or claim 9, it is characterised in that with Described pyrolysis gas outlet is provided with and communicated with cooling purifying device (6), and described cooling purifying device (6) sets It is equipped with tar outlet, cooled coal gas outlet and coke breeze outlet；

The outlet of described coke breeze, the coal dust outlet of described high-temperature dust removing device (3) and described dedusting cooling dress The coal dust outlet import with described gasification furnace (2) respectively putting (5) is connected；

It is connected with burner, the gas outlet of described burner and institute with the outlet of described cooled coal gas State heat smoke outlet to be connected.