CN103788975A - Method for microwave pyrolysis utilization of lignite - Google Patents
Method for microwave pyrolysis utilization of lignite Download PDFInfo
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- CN103788975A CN103788975A CN201410028331.6A CN201410028331A CN103788975A CN 103788975 A CN103788975 A CN 103788975A CN 201410028331 A CN201410028331 A CN 201410028331A CN 103788975 A CN103788975 A CN 103788975A
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Abstract
The invention discloses a method for microwave pyrolysis utilization of lignite. The method comprises the steps of (1) smashing lignite to form powdered raw materials, and conveying the raw materials into a drying device for drying to obtain dried powdered raw materials; (2) heating the dried powdered raw materials in the step (1) to 400-600 DEG C by taking microwaves as a heat source, and preserving the heat for 20-60 minutes to obtain a semi-coked product and oil gas mixture; and (3) separating out tar and pyrolysis gas from the obtained oil gas mixture through a condenser, conveying the pyrolysis gas into a combustion device for combustion to generate flue gas, and conveying the flue gas into the drying device in the step (1) to be used as a drying medium. The method has the advantages of simple technology, high processing efficiency, short flow, easiness in operation and the like and can improve the comprehensive utilization efficiency of lignite.
Description
Technical field
The present invention relates to a kind of method that brown coal utilize, particularly relate to a kind of method that brown coal microwave-heating utilizes.
Background technology
Brown coal, have another name called bavin coal, are the pit coals that degree of coalification is minimum, are a kind of brownish black, lacklustre grizzles between peat and pitch coal, it is characterized by Gao Shui, hyperoxia, high-volatile, middle ash, low fixed carbon and lower calorific value etc.Brown coal chemical reactivity is strong, and easily weathering in air is difficult for storing and fortune far away.
Nineteen ninety-five is verified 1,303 hundred million tons of brown coal retained reserves by China, account for the whole world and verify 15% left and right of coal retained reserve, predicting the newly-increased amount of verifying in 2015 is 2,600 hundred million tons, planning the year two thousand twenty whole nation produces 21.5 hundred million tons, brown coal raw coal, almost all be distributed in industrial under-developed area, maximum with the Inner Mongol, northeast and Yunnan Province.
At present global energy is increasingly under intense situation, and the with low cost and relevant processing technology of brown coal is progressively paid attention to by world energy sources circle again.Brown coal are mainly as the fuel in power station, both can make industrial chemicals, sorbent material, support of the catalyst and purify waste water etc., also can directly be used as the raw material of industrial heat resources, gasification, low-temperature pyrolysis etc.But after brown coal drying, the special properties such as the efflorescence of easily chapping, poor heat stability, burning-point is low, reactive behavior is strong, oxidizable spontaneous combustion, make its processed and applied be subject to certain limitation.
The Upgrading Processes of brown coal mainly comprises brown coal solid heat carrier pyrolysis (ETCH1-175) technique of German Lurgi-Ruhrgas pyrolytic process, USSR (Union of Soviet Socialist Republics), gentleness gasification (Encoal) technology of the U.S., Development of Coal Flash Pyrolysis Process, brown coal solid thermal carriers destructive distillation Poly-generation (DG) technique of Dalian University of Technology's research and development and the multistage rotary kiln pyrolytic process of Beijing Coal Chemical Industry branch research and development etc. of Japan.Due to brown coal bad adhesion, when pyrolysis, do not produce plastic mass, common pyrolysis installation all adopts internal heat type.The at present main pyrolysis type of furnace as thermal source that is same producer gas with air as thermal source or employing pyrolysis char adopting.Wherein, the former is owing to containing a large amount of nitrogen in air, and in discharged producer gas, nitrogen content is higher, causes that coal is large-minded, calorific value is low, is follow-uply difficult to comprehensive utilization, causes the significant wastage of resource; The latter adopts solid thermal carriers type of heating, the heat and mass transfer process more complicated of its system own, and process control is more difficult.Tradition pyrolysis adopts electric heating or high-temperature medium type of heating, heat imports inside into from material surface, gas-phase product is from inside to outside diffusion, its heat and mass opposite direction, easily cause the second pyrolysis of product, and heating rate is little, lack of homogeneity, the tar rate of recovery is low, can not obtain the pyrolysis furnace gas with better utility value.For overcoming above shortcoming, researchist has proposed the rapid pyrolysis method such as fluidized-bed, plasma body, but exists material to need the shortcomings such as fragmentation, current consumption are large, and its basic heat and mass mode does not change.
Microwave heating is a kind of new type of heating, there is the features such as rate of heating is fast, calorific loss is little, easy to operate, and carbon is a kind of good microwave absorption, can be heated by selectivity, and carbon-coating surface can generate stability microwave plasma slab under microwave irradiation, form hot localised points, thus the heat-processed of strengthening W-response.Compared with traditional pyrolysis, microwave-heating has unique heat and mass rule and better heating uniformity, more easily regulating and controlling temperature and pyrolytic process.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of method that brown coal microwave-heating utilizes.The present invention is by carrying out microwave-heating to brown coal, the shortcoming that can solve that the temperature that prior art exists is high, energy consumption is large, utilization ratio is low etc., and have that technique is simple, working (machining) efficiency is high, flow process is short, easy handling, can improve the advantage such as comprehensive utilization ratio of brown coal.
For solving the problems of the technologies described above, the method that brown coal microwave-heating of the present invention utilizes, comprises step:
1) brown coal are pulverized, formed powder stock, and send into drying installation and be dried, obtain dried powder raw material;
2) take microwave as thermal source, by dried powder heating raw materials to 400～600 ℃ of step 1), and keep certain residence time, as keep 20～60min, make the complete pyrolysis of raw material, obtain semicoke product and gas-oil mixture;
3) by step 2) gas-oil mixture that obtains isolates tar and pyrolysis gas (being that gas-oil mixture is to be made up of tar and pyrolysis gas) through condenser, this pyrolysis gas send into combustion unit burn produce flue gas, and the drying installation that this flue gas is sent into step 1) is as drying medium, is back to combustion heat supplying by pyrolysis gas.
In described step 1), the water content of brown coal is 20～60%(weight percent); The particle diameter of powder stock is 0.5～2mm; Dry temperature is 120～200 ℃; The water content of dried powder raw material is 1～10%(weight percent).
Described step 2) in, semicoke product and gas-oil mixture are all semicoke product and the gas-oil mixtures of high-carbon content (>80%).
In described step 3), the condensed temperature of pyrolysis gas is controlled at below 80 ℃; The temperature of flue gas is controlled at 120～200 ℃ (being that the flue-gas temperature from combustion unit that drying installation uses is 120～200 ℃).
In the present invention, semicoke product is the ature of coal mixture of high-carbon content, and tar is the mixture of phenol and hydrocarbon.
The present invention is that a kind of clean, efficient brown coal utilize method, and its concrete beneficial effect is as follows:
1) microwave-heating can improve pyrolysis rate greatly, and Reaction time shorten improves plant efficiency.
2) existence in microwave plasma district can reduce pyrolysis reaction temperature, gaseous product CO
2under microwave exposure, can there is at a lower temperature reforming reaction, improve H
2with CO equal size, increase gas heating value.
3) combustion and pyrolysis gas is brown coal drying complementary heating, realizes energy partly self-supporting, and the dried recovered of water has reduced the discharge of waste water after pyrolysis simultaneously.
4) shorter, the environmental friendliness of simple and convenient, the short easy handling of flow process of technique of the present invention, production cycle, security of system are reliable.
Accompanying drawing explanation
Below in conjunction with accompanying drawing and embodiment, the present invention is further detailed explanation:
Fig. 1 is the device schematic diagram that method of the present invention adopts.Wherein, 1 is pulverizer, and 2 is moisture eliminator, and 3 is microwave reactor, and 4 is semicoke collector, and 5 is condenser, and 6 is tar well, and 7 is combustion unit.
Embodiment
Operating process in following examples is as follows:
It is the particle of particle diameter 0.5～2mm that brown coal raw material is delivered in pulverizer 1 by pulverizing by feed bin, then is delivered to moisture eliminator 2, in electrically heated and to be dried to moisture content under by following 120～200 ℃ of produced flue gas heating be 1～10%.Dried brown coal particle is admitted in microwave reactor 3, and microwave heating, to required pyrolysis temperature, is carried out pyrolysis, obtains semicoke product and gas-oil mixture.
Wherein, semicoke product introduction semicoke collector 4; Gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas (flammable pyrolysis gas).Tar products enters tar well 6.The condensed temperature of pyrolysis gas is controlled at below 80 ℃, and by pyrolysis gas send into combustion unit 7 burn produce flue gas, control flue-gas temperature be 120～200 ℃, flue gas enters moisture eliminator 2 and contacts and take away moisture with brown coal.Calculate semicoke and tar yield after pyrolysis, and measure pyrolysis gas composition.
Now with specific embodiment, the method that brown coal microwave-heating utilizes is described.
Embodiment 1
Be 20%(weight percent by water content) brown coal powder be broken into after the powder of 0.5mm, be delivered to moisture eliminator 2, being dried to moisture content is 5%(weight percent), take microwave as thermal source, brown coal are heated to 600 ℃, keep after 20min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
The brown coal powder that is 30% by water content is broken into after the powder of 1.5mm, is delivered to moisture eliminator 2, and being dried to moisture content is 1%, take microwave as thermal source, brown coal is heated to 500 ℃, keeps after 30min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
Embodiment 3
The brown coal powder that is 40% by water content is delivered to moisture eliminator 2 after being broken into the powder of 2.0mm, and being dried to moisture content is 10%, take microwave as thermal source, brown coal is heated to 400 ℃, keeps after 60min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
The brown coal powder that is 40% by water content is delivered to moisture eliminator 2 after being broken into the powder of 1.0mm, and being dried to moisture content is 6%, take microwave as thermal source, brown coal is heated to 450 ℃, keeps after 50min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
The brown coal powder that is 50% by water content is delivered to moisture eliminator after being broken into the powder of 1.5mm, and being dried to moisture content is 5%, take microwave as thermal source, brown coal is heated to 550 ℃, keeps after 35min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
The brown coal powder that is 60% by water content is delivered to moisture eliminator after being broken into the powder of 1.0mm, and being dried to moisture content is 10%, take microwave as thermal source, brown coal is heated to 500 ℃, keeps after 40min cooling semicoke product and the gas-oil mixture of obtaining.This gas-oil mixture, through condenser 5 condensations, is isolated tar products and pyrolysis gas.With this pyrolysis gas of gas chromatographic detection composition (Ar is carrier gas for Shimadzu 2014C, TCD detector, TDX-1 packed column, post case temperature is 100 ℃).
After brown coal pyrolysis, the results are shown in Table 1.
The pyrolytic reaction result of table 1 embodiment
65% left and right (mass percent) known through above-described embodiment, after brown coal microwave-heating, gained semicoke is raw material, 10～15% left and right (mass percent) that tar is raw material, the H in pyrolysis gas
2account for 66～80%(molar percentage of total tolerance with CO sum), the overall utilization rate of brown coal is higher.
Finally, it is also to be noted that, what more than enumerate is only several specific embodiments of the present invention.Obviously, the invention is not restricted to above embodiment, can also have many distortion.All distortion that those of ordinary skill in the art can directly derive or associate from content disclosed by the invention, all should think protection scope of the present invention.
Claims (7)
1. the method that brown coal microwave-heating utilizes, is characterized in that, comprises step:
1) brown coal are pulverized, formed powder stock, and send into drying installation and be dried, obtain dried powder raw material;
2) take microwave as thermal source, by dried powder heating raw materials to 400～600 ℃ of step 1), and keep 20～60min, obtain semicoke product and gas-oil mixture;
3) by step 2) gas-oil mixture that obtains isolates tar and pyrolysis gas through condenser, and this pyrolysis gas is sent into combustion unit and is burnt and produce flue gas, and the drying installation that this flue gas is sent into step 1) is as drying medium.
2. the method for claim 1, is characterized in that: in described step 1), the water content of brown coal is 20～60%.
3. the method for claim 1, is characterized in that: in described step 1), the particle diameter of powder stock is 0.5～2mm.
4. the method for claim 1, is characterized in that: in described step 1), dry temperature is 120～200 ℃.
5. the method for claim 1, is characterized in that: in described step 1), the water content of dried powder raw material is 1～10%.
6. the method for claim 1, is characterized in that: in described step 3), the condensed temperature of pyrolysis gas is controlled at below 80 ℃.
7. the method for claim 1, is characterized in that: in described step 3), the temperature of flue gas is controlled at 120～200 ℃.
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Cited By (6)
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| CN105843287A (en) * | 2016-03-22 | 2016-08-10 | 中国科学院上海高等研究院 | Microwave pyrolysis biomass real-time panoramic temperature monitoring, regulation and control system and method |
| CN106016971A (en) * | 2016-05-18 | 2016-10-12 | 内蒙古工业大学 | Gradient upgrading method for lignite |
| CN107858164A (en) * | 2017-11-23 | 2018-03-30 | 神雾环保技术股份有限公司 | A kind of coal sub-prime utilizes the system and method for preparing oil product and acetylene |
| CN108251140A (en) * | 2018-02-08 | 2018-07-06 | 淮阴师范学院 | A kind of method using microwave catalysis pyrolysis biomass orientation production biomass carbon |
| CN108955095A (en) * | 2018-08-09 | 2018-12-07 | 太原理工大学 | A kind of lignite microwave drying process |
| WO2022016800A1 (en) * | 2020-07-23 | 2022-01-27 | 东南大学 | Biomass pyrolysis device and method with optimized matching of thermal energy and microwave energy |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105843287A (en) * | 2016-03-22 | 2016-08-10 | 中国科学院上海高等研究院 | Microwave pyrolysis biomass real-time panoramic temperature monitoring, regulation and control system and method |
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| CN107858164A (en) * | 2017-11-23 | 2018-03-30 | 神雾环保技术股份有限公司 | A kind of coal sub-prime utilizes the system and method for preparing oil product and acetylene |
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| WO2022016800A1 (en) * | 2020-07-23 | 2022-01-27 | 东南大学 | Biomass pyrolysis device and method with optimized matching of thermal energy and microwave energy |
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Inventor after: Sun Yuhan Inventor after: Li Jinping Inventor after: Xiao Yaning Inventor after: Luo Hu Inventor after: Kong Lingzhao Inventor after: Tang Zhiyong Inventor after: Miao Gai Inventor after: Wei Weiqi Inventor after: Liu Bin Inventor before: Sun Yuhan Inventor before: Luo Hu Inventor before: Kong Lingzhao Inventor before: Tang Zhiyong Inventor before: Miao Gai Inventor before: Wei Weiqi Inventor before: Li Jinping Inventor before: Xiao Yaning Inventor before: Liu Bin |
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