CN107010852B - A kind of light calcined magnesia production method - Google Patents

A kind of light calcined magnesia production method Download PDF

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Publication number
CN107010852B
CN107010852B CN201710260723.9A CN201710260723A CN107010852B CN 107010852 B CN107010852 B CN 107010852B CN 201710260723 A CN201710260723 A CN 201710260723A CN 107010852 B CN107010852 B CN 107010852B
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magnesite
light
microwave
calcined magnesia
silicon carbide
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CN107010852A (en
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郭玉香
曲殿利
彭强
王春新
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University of Science and Technology Liaoning USTL
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2/00—Lime, magnesia or dolomite
    • C04B2/10—Preheating, burning calcining or cooling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/40—Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
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Abstract

The present invention relates to metallurgical technology field more particularly to a kind of light calcined magnesia production methods.Using the magnesite for being less than 30mm granularity as raw material, it is passed in rotary microwave roaster and is mixed with re-crystallized silicon carbide ball；Light calcined magnesia is produced using re-crystallized silicon carbide ball as microwave coupling agent indirect heating magnesite, magnesite is coupled agent re-crystallized silicon carbide ball grinding into high activity light-magnesite powder while being calcination into light calcined magnesia, while high efficiency, low cost recycles magnesium carbonate and decomposes the high concentration CO generated2Gas.The resource for being capable of processing existing technique not is effectively utilized；Magnesite while being calcination into light calcined magnesia by grinding at high activity light-magnesite powder, increase the activity of product, improve the quality of product, eliminate crushing link, simplify process, production process is easily controllable；Using the method for on-fuel combustion heating calcined magnesite, CO is realized2High efficiency, low cost recycling, alleviates environmental pollution.

Description

A kind of light calcined magnesia production method
Technical field
The present invention relates to metallurgical technology field more particularly to a kind of light calcined magnesia production methods.
Background technique
Magnesite is one of the Dominant Mineral Resources in China, more than 30 hundred million tons of gross reserves, accounts for four points of world's magnesite ore reserves One of, it occupies first of the world.The light-magnesite powder that magnesite is sintered into is metallurgy, refractory material, building materials, chemical industry, papermaking, rubber The indispensable raw mineral materials in the fields such as glue, plastics, coating, medicine, chemical fertilizer, development and application are quickly grown and increasingly extensive.
China generally uses reflecting kiln to calcine by the active light calcined magnesia of magnesite production at present, and production technology existing 70~ 80 years history.Giobertite is added by reflecting kiln kiln top, is heated to 1000 DEG C of decomposition through Semi-gas burning mode in kiln, is decomposed Material enters kiln bottom feed bin afterwards, and manually splicing trolley shifts 400~800 DEG C of high-temperature materials onto stock ground to topple over ground naturally cold But blocky light calcined magnesia, then through artificial heat choosing is obtained, obtains light-magnesite powder after milling equipment is ground.Reflecting kiln can only Lump ore (50~300mm) raw material is roasted, and is simply equipped, backward in technique, production efficiency is low, and energy consumption is high, and Product Activity is low, matter Poor, serious waste of resources is measured, labor operation condition is poor, and dust pollution is serious.
The main component of magnesite is magnesium carbonate (MgCO3), theory group becomes MgO47.81%, CO252.19%, in water chestnut In the calcination process of magnesium mine, MgCO3Decompose the CO for generating about 5l% or so2Gas.By calculating it is found that 1 ton of light-burned oxidation of production Magnesium powder need to averagely use 2.3 tons of level-one magnesite ore, consume 0.3 ton of standard coal.It is decomposed by magnesite per ton and generates 0.51 ton CO2Gas, C burning generates 3.4 tons of CO in coal per ton2Gas calculates, and 1 ton of light-magnesite powder of every production will generate 2.19 tons CO2Gas.China's light calcined magnesia annual capacity will generate nearly 22,000,000 tons of CO at 10,000,000 tons or more every year2, these CO2With it is anti- The flue gas that fuel combustion generates in kiln to be penetrated to mix, concentration is very low, generally 10%~20%, it is difficult Collection utilization, These mixed gas are discharged into atmosphere, cause serious environmental pollution.Some magnesite processing enterprises, China taste in recent years Examination recycles CO from the exhaust gas being discharged in magnesite calcination process2, increase recycling during magnesite produces light calcined magnesia Device, by the CO of outlet2Gas recycling.However, exhaust gas flow is extremely unstable, and exhaust gas is not easy due to reflecting kiln list kiln small scale It collects, especially exhausted air quantity is big, wherein CO2The concentration of gas is low, causes CO2Reclaimer investment is big, and operating cost is excessively high, raw Enterprise is produced to be difficult to receive.The trial of these enterprises has failed and has come to an end, and causes very huge economic loss.
Summary of the invention
The present invention provides a kind of light calcined magnesia production method, using the magnesite of 0~30mm granularity as raw material, using tying again Crystalline substance carbonization silicon ball produces light calcined magnesia as microwave coupling agent indirect heating magnesite, and magnesite is calcination into light-burned oxidation It is coupled agent re-crystallized silicon carbide ball grinding while magnesium into high activity light-magnesite powder, improves the activity of product, saves Crushing link, simplifies process flow, so that magnesium carbonate decomposes the high concentration CO generated2Gas is able to high efficiency, low cost and returns It receives and utilizes.
In order to achieve the above object, the present invention is implemented with the following technical solutions:
A kind of light calcined magnesia production method, using re-crystallized silicon carbide ball as microwave coupling agent indirect heating magnesite Produce light calcined magnesia, magnesite be coupled while being calcination into light calcined magnesia agent re-crystallized silicon carbide ball grinding at High activity light-magnesite powder, while high efficiency, low cost recycles magnesium carbonate and decomposes the high concentration CO 2 gas generated, it is specific to wrap Include following steps:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed into rotary microwave roaster with roasting furnace chamber Partial size be 1~120mm re-crystallized silicon carbide ball uniformly mix；Magnesite mass percentage is 10%~80%, then is tied Crystalline substance carbonization silicon ball mass percentage is 20%~90%.
(2) rotary microwave roaster uses frequency to be used as heat for the microwave that 900~3000MHZ industrial microwave source generates Source, re-crystallized silicon carbide ball are warming up to 650~1000 DEG C as microwave coupling agent and microwave efficient coupling, in 1~20min；
(3) under the action of couplant, it is light that magnesite, which is indirectly heated to 600~950 DEG C of progress decomposition reaction calcinings, Burned magnesium oxide, while generating the CO that concentration is 90%~98%2。
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 50~1500mm Under, material is impacted and is ground, magnesite while being calcination into light calcined magnesia by grinding at granularity be 0~ The high activity light-magnesite powder of 1mm.
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.
Compared with prior art, the beneficial effects of the present invention are:
1) to be less than 30mm muck as raw material, the resource for being capable of processing existing technique not is effectively utilized；
2) magnesite while being calcination into light calcined magnesia by grinding at high activity light-magnesite powder, increase The activity of product improves the quality of product, eliminates crushing link, simplifies process, so that production process is easily controllable；
3) method for using on-fuel combustion heating calcined magnesite generates flue gas, magnesite calcining without fuel combustion It decomposes and generates high concentration CO2, realize CO2High efficiency, low cost recycling, alleviates environmental pollution.
Specific embodiment
Specific embodiments of the present invention will be further explained below:
A kind of light calcined magnesia production method, using re-crystallized silicon carbide ball as microwave coupling agent indirect heating magnesite Produce light calcined magnesia, magnesite be coupled while being calcination into light calcined magnesia agent re-crystallized silicon carbide ball grinding at High activity light-magnesite powder, while high efficiency, low cost recycles magnesium carbonate and decomposes the high concentration CO generated2Gas, it is specific to wrap Include following steps:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed into rotary microwave roaster with roasting furnace chamber Partial size be 1~120mm re-crystallized silicon carbide ball uniformly mix；Magnesite mass percentage is 10%~80%, then is tied Crystalline substance carbonization silicon ball mass percentage is 20%~90%.
To be less than the broken magnesite of 30mm as raw material, the resource for being capable of processing existing technique not is effectively utilized the present invention.
(2) rotary microwave roaster uses frequency to be used as heat for the microwave that 900~3000MHZ industrial microwave source generates Source, re-crystallized silicon carbide ball are warming up to 650~1000 DEG C as microwave coupling agent and microwave efficient coupling, in 1~20min.
Microwave heating is a kind of completely new heat energy technology, and heating does not need external heat source, is to utilize microwave and substance Interaction directly heats the thermal energy that microwave energy is substance to material.Compared with traditional technology, microwave technology also has Following advantage: the instantaneity 1. heated, microwave equipment plug and play, without preheating is without waste heat, flexible and convenient operation, convenient for control. 2. the globality heated, microwave is a kind of electromagnetic wave that penetration power is strong, and when handling material, each position of material is uniform simultaneously Heating, temperature gradient is small, is a kind of " body heat source ".3. the selectivity heated can use the selectivity of microwave heating to mixing The different parts of each component or part in material carry out selective heating.4. the high efficiency of energy utilization, additional energy damage Consume small, thermal efficiency height.5. have controllability, for the degree of microwave heating material can by adjust microwave irradiation time come into Row control, it is easy to operate.
(3) under the action of couplant, it is light that magnesite, which is indirectly heated to 600~950 DEG C of progress decomposition reaction calcinings, Burned magnesium oxide, while generating the CO that concentration is 90%~98%2。
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 50~1500mm Under, material is impacted and is ground, magnesite while being calcination into light calcined magnesia by grinding at granularity be 0~ The high activity light-magnesite powder of 1mm.
Magnesite while being calcination into light calcined magnesia by grinding at high activity light-magnesite powder, increase production The activity of product improves the quality of product, eliminates crushing link, simplifies process, so that production process is easily controllable.
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.CO after the recovery2 It can be made into the technical grade liquid or solid CO that purity is 99.5%2The food-class CO that (dry ice) or purity are 99.9%2。
Using the method for on-fuel combustion heating calcined magnesite, flue gas, magnesite calcining point are generated without fuel combustion Solution generates high concentration CO2, it can be achieved that high efficiency, low cost recycles, environmental pollution is alleviated.
Embodiment 1:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed into rotary microwave roaster with roasting furnace chamber Partial size be 20~50mm re-crystallized silicon carbide ball uniformly mix；Magnesite mass percentage is 30%, recrystallization carbonization Silicon ball mass percentage is 70%.
(2) microwave that rotary microwave roaster uses frequency to generate for 915MHZ industrial microwave source is as heat source, then ties Crystalline substance carbonization silicon ball is warming up to 750 DEG C in 10min as microwave coupling agent and microwave efficient coupling.
(3) under the action of couplant, it is light-burned oxidation that magnesite, which is indirectly heated to 700 DEG C of progress decomposition reaction calcinings, Magnesium, while generating the CO that concentration is 90%~98%2。
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 150mm, to object Material is impacted and is ground, and magnesite at granularity is 0~0.088mm by grinding while being calcination into light calcined magnesia High activity light-magnesite powder.
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.
Embodiment 2:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed into rotary microwave roaster with roasting furnace chamber Partial size be 30~80mm re-crystallized silicon carbide ball uniformly mix；Magnesite mass percentage is 35%, recrystallization carbonization Silicon ball mass percentage is 65%.
(2) microwave that rotary microwave roaster uses frequency to generate for 2450MHZ industrial microwave source is as heat source.It ties again Crystalline substance carbonization silicon ball is warming up to 900 DEG C in 15min as microwave coupling agent and microwave efficient coupling.
(3) under the action of couplant, it is light-burned oxidation that magnesite, which is indirectly heated to 850 DEG C of progress decomposition reaction calcinings, Magnesium, while generating the CO that concentration is 90%~98%2。
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 300mm, to object Material is impacted and is ground, the height that magnesite is 0~0.5mm at granularity by grinding while being calcination into light calcined magnesia Active light-magnesite powder.
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.
Embodiment 3:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed into rotary microwave roaster with roasting furnace chamber Partial size be 40~100mm re-crystallized silicon carbide ball uniformly mix；Magnesite mass percentage is 40%, recrystallization carbonization Silicon ball mass percentage is 60%.
(2) microwave that rotary microwave roaster uses frequency to generate for 915MHZ industrial microwave source is as heat source.It ties again Crystalline substance carbonization silicon ball is warming up to 950 DEG C in 18min as microwave coupling agent and microwave efficient coupling.
(3) under the action of couplant, it is light-burned oxidation that magnesite, which is indirectly heated to 900 DEG C of progress decomposition reaction calcinings, Magnesium, while generating the CO that concentration is 90%~95%2。
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 500mm, to object Material is impacted and is ground, and magnesite is lived by grinding at the height that granularity is 0~1mm while being calcination into light calcined magnesia Property light-magnesite powder.
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.

Claims (2)

1. a kind of light calcined magnesia production method, which is characterized in that indirect as microwave coupling agent using re-crystallized silicon carbide ball It heats magnesite and produces light calcined magnesia, magnesite is coupled agent recrystallization carbonization while being calcination into light calcined magnesia Silicon ball grinding is at high activity light-magnesite powder, while high efficiency, low cost recycles magnesium carbonate and decomposes the high concentration CO generated2 Gas specifically comprises the following steps:
(1) the magnesite feedstock transportation of 0~30mm granularity is placed again into rotary microwave roaster with roasting furnace chamber Crystalline silicon carbide silicon ball uniformly mixes；
Magnesite mass percentage is 10%~80%, and re-crystallized silicon carbide ball mass percentage is 20%~90%；
(2) microwave that rotary microwave roaster uses frequency to generate for 900~3000MHZ industrial microwave source is as heat source, then Crystalline silicon carbide silicon ball is warming up to 650~1000 DEG C as microwave coupling agent and microwave efficient coupling, in 1~20min；
(3) under the action of couplant, it is light-burned oxygen that magnesite, which is indirectly heated to 600~950 DEG C of progress decomposition reaction calcinings, Change magnesium, while generating the CO that concentration is 90%~98%2；
(4) in calcination process, with the rotation of roaster, re-crystallized silicon carbide ball is fallen after being elevated 50~1500mm, right Material is impacted and is ground, the height that magnesite is 0~1mm at granularity by grinding while being calcination into light calcined magnesia Active light-magnesite powder；
(5) magnesite is decomposed to the CO that the concentration generated is 90%~98%2It is recycled by recyclable device.
2. a kind of light calcined magnesia production method according to claim 1, which is characterized in that step (1) recrystallization The partial size for the silicon ball that is carbonized is 1~120mm.
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Publication number Priority date Publication date Assignee Title
CN108249786B (en) * 2018-01-23 2020-07-03 辽宁瀚海工业机电设备有限公司 Method for continuously producing active magnesium oxide and recovering carbon dioxide by heating magnesite with microwaves

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1884170A (en) * 2006-06-28 2006-12-27 满意 Method for sintering and soft burning magnesia in tunnel kiln by using magnesite powder and particles
CN102020250A (en) * 2009-09-18 2011-04-20 昆明理工大学 New method for producing sulphuric acid and generation joint product cement by decomposing phosphogypsum through microwave reduction
CN102230223A (en) * 2011-06-16 2011-11-02 申偲伯 Method for preparing magnesium potassium titanate by directly utilizing magnesium oxide
CN104071993A (en) * 2014-06-26 2014-10-01 郑州德朗能微波技术有限公司 Magnesite/dolomite microwave light-burning device and method
CN203923022U (en) * 2014-06-26 2014-11-05 郑州德朗能微波技术有限公司 The device of a kind of microwave light-calcined magnesite, rhombspar
CN106186737A (en) * 2016-07-12 2016-12-07 海城市恒镁科技有限公司 A kind of method of the eco-friendly light-burned good quality magnesium oxide of magnesite concentrate

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1884170A (en) * 2006-06-28 2006-12-27 满意 Method for sintering and soft burning magnesia in tunnel kiln by using magnesite powder and particles
CN102020250A (en) * 2009-09-18 2011-04-20 昆明理工大学 New method for producing sulphuric acid and generation joint product cement by decomposing phosphogypsum through microwave reduction
CN102230223A (en) * 2011-06-16 2011-11-02 申偲伯 Method for preparing magnesium potassium titanate by directly utilizing magnesium oxide
CN104071993A (en) * 2014-06-26 2014-10-01 郑州德朗能微波技术有限公司 Magnesite/dolomite microwave light-burning device and method
CN203923022U (en) * 2014-06-26 2014-11-05 郑州德朗能微波技术有限公司 The device of a kind of microwave light-calcined magnesite, rhombspar
CN106186737A (en) * 2016-07-12 2016-12-07 海城市恒镁科技有限公司 A kind of method of the eco-friendly light-burned good quality magnesium oxide of magnesite concentrate

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