CN103058245B - Equipment and technology of calcium oxide producing with calcium sulfate - Google Patents

Equipment and technology of calcium oxide producing with calcium sulfate Download PDF

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Publication number
CN103058245B
CN103058245B CN201210564848.8A CN201210564848A CN103058245B CN 103058245 B CN103058245 B CN 103058245B CN 201210564848 A CN201210564848 A CN 201210564848A CN 103058245 B CN103058245 B CN 103058245B
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digestion chamber
kiln
calcium
filter screen
calcium oxide
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CN103058245A (en
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刘立文
刘珍如
宁爱民
宁勇
宁江天
刘勇
鲁纪鸣
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Hunan Fu Xiang New Type Building Material Co Ltd
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/10Process efficiency
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/10Process efficiency
    • Y02P20/129Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines

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  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

The invention provides equipment and technology of calcium oxide producing with calcium sulfate. The equipment comprises a calcining kiln, a digestion chamber and a secondary calcining kiln, wherein the calcining kiln is communicated with a feed port at the top of the digestion chamber through a discharge port I at the bottom of the calcining kiln, the digestion chamber is divided into two layers which are separated through a filter screen I in the middle. A carbon dioxide inlet pipeline is arranged on the side wall of the digestion chamber and leads to the bottom of the digestion chamber, a discharge port II is arranged at the bottom of the digestion chamber and is provided with a filter screen II and a separating hopper, the filter screen II is in an inclined structure, a heat exchanger is arranged outside the wall of the digestion chamber, the separating hopper directly leads into a drying chamber with an open structure, the drying chamber is communicated with the secondary calcining kiln, the heat exchanger is connected with a heater, a condenser and a circulating pump in a closed mode in sequence through pipelines, and the heater is positioned at the bottom of the drying chamber. The invention further includes the technology of waste heat recovering with the equipment. Energy consumption is reduced by 10% or more, meanwhile purity and production efficiency of the calcium oxide product can be improved.

Description

A kind of calcium sulfate produces the equipment and technology of calcium oxide
Technical field
The present invention relates to a kind of equipment and technology producing calcium oxide, especially relate to the equipment and technology that a kind of calcium sulfate produces calcium oxide.
Background technology
Calcium oxide is widely used in and manufactures calcium carbide, soda ash, chlorinated lime, refractory materials, as siccative and soil improvement agent; As analytical reagent, the fusing assistant manufacturing fluorescent material; For process hides, purification of waste water; As material of construction, metallurgical fusing assistant; It is the main raw material of hydrogen manufacturing calcium oxide and various calcium cpd.
Traditional calcium oxide production method is mainly raw material with Wingdale, and calcining process adopts shaft furnace, Wingdale and solid fuel is mixed or layering loads in kiln and burns.Also utilizing calcium sulfate to carry out calcining as raw material in recent years more and more and prepare calcium oxide, in order to prepare the high calcium oxide of purity, often needing to purify to product.Its main technique is, is dropped into by mixture in water and calcium oxide is digested, and generates calcium hydroxide, calcium hydroxide is water-soluble, and elimination impurity, obtains aqua calcis, then in aqua calcis, carbonic acid gas is passed into, reaction generates calcium carbonate, by calcination of calcium carbonate, namely obtains the calcium oxide that purity is higher, in the process, the digestion of calcium oxide is a heat-producing chemical reaction process, and the heat wherein produced is appreciable, and fully these heats of recycling are vital tasks in this technique.But the heat that this process produces is not again high especially, recovery difficult is large, therefore most of manufacturer does not reclaim the low temperature exhaust heat in this process, simultaneously in order to ensure that certain temperature of reaction needs again to pass into circulating water and carries out heat exchange cooling to reactor, do like this, not only low temperature exhaust heat is not used, and also needs to use a large amount of cold water, has not only wasted energy but also waste water resource.
Chinese invention patent application 200510022528.X discloses the novel method of Waste Heat Reuse in fluidizing furnace in a kind of sulphuric acid process, heating water will be used for or air realizes providing hot water and heating installation to user respectively from flue gas out in fluidizing furnace, but this application is subject to region and environmental limit, the feasibility of application is also little.
Chinese utility model patent 200820019657.2 discloses a kind of closed residual heat of sulfuric acid production that utilizes and carries out the device heated, it carrys out water in heating pipe to user's heat supply using acid cooler as medium, but user must be separated by comparatively near with equipment, otherwise application performance is bad.
Summary of the invention
The technical problem to be solved in the present invention is, overcome equipment low temperature exhaust heat waste in existing calcium oxide production process serious, and affect a difficult problem for speed of reaction, provide one to utilize low temperature exhaust heat, reduce energy expenditure, the equipment and technology producing calcium oxide with calcium sulfate of enhancing productivity.
The technical scheme that the present invention solves the employing of its technical problem is:
The equipment producing calcium oxide with calcium sulfate of the present invention, comprise calcining kiln, digestion chamber, secondary clacining kiln, described calcining kiln is communicated with digestion chamber's its top feed mouth by bottom discharge mouth I, and described digestion chamber is divided into two-layer, and centre is separated by filter screen I; Digestion chamber's sidewall is also provided with and passes into pipeline towards the carbonic acid gas bottom digestion chamber, the discharge port II of band filter screen II and separating bucket is provided with bottom digestion chamber, described filter screen II is incline structure, be 10-60 degree with horizontal angle, one end that filter screen II is lower maintains an equal level with the lower end being separated quarrel, digestion locular wall peripheral hardware has interchanger, separating bucket directly passes in the kiln of open design, described kiln communicates with secondary clacining kiln, and described interchanger is formed with well heater, condenser, recycle pump successively to close by pipeline and is connected; Described well heater is positioned at the bottom of kiln.
Further, described filter screen II is 45 degree with horizontal angle.
Further, the order number of described filter screen I and filter screen II is 1500-4000 order (preferably 3000 orders).
The equipment work process of producing calcium oxide with calcium sulfate of the present invention, i.e. the technique of producing calcium oxide with calcium sulfate of the present invention, comprises following two-part step:
Material production process: generation calcium oxide is decomposed in calcium sulfate high-temperature calcination in calcining kiln, blended solid powder in calcining kiln is successively by the discharge port I bottom calcining kiln, digestion chamber's its top feed mouth enters digestion chamber, in digestion chamber, digested reaction generates calcium hydroxide to calcium oxide, and produce amount of heat, calcium hydroxide is water-soluble and other impurity is water insoluble, filtered by the filter screen I being positioned at the 1500-4000 order (preferably 3000 orders) in the middle of digestion chamber, upper strata, digestion chamber is the mixture of calcium hydroxide and impurity, lower floor is aqua calcis, pass into pipeline by the carbonic acid gas of digestion chamber's sidewall simultaneously and pass into carbon dioxide in calcium hydroxide aqueous solution, generate precipitation of calcium carbonate, after the filtration of digestion chamber's bottom screen II, filter screen II top is the calcium carbonate powders containing moisture, calcium carbonate powders containing moisture is transported to kiln through separating bucket, and (filter screen II is incline structure on the one hand, the operation of particle can be promoted, on the other hand, the carbonic acid gas led to can make liquid turbulization, oscillation action is produced to filter screen II, promote the descending of material), filtrate is discharged through discharge port II lower end, calcium carbonate powders is after kiln drying, send into the calcining of secondary clacining kiln, the calcium oxide that purity is higher can be obtained.
Filter screen I filters in dissolution process not have dissolved impurity, and through filter screen I filtration is aqua calcis; Pass in calcium hydroxide aqueous solution after carbonic acid gas, might not react completely and generate precipitation of calcium carbonate, and the effect of filter screen II is the precipitation isolating generation, the calcium hydroxide aqueous solution of non-complete reaction is prevented too much to enter kiln and secondary clacining kiln along with precipitation, be converted into calcium hydroxide solid impurity, affect purity, thus reduce the foreign matter content of the finished product.
Recycle heat process: the digestion of digestion chamber's calcium oxide can discharge a large amount of heat, be fixed on the interior logical high temperature heat conductive oil (high-temperature heat-conductive oil flash point >=320 DEG C) of interchanger of digestion chamber's outer wall, high temperature heat conductive oil absorbs heat, and flowing is passed to the well heater be positioned at bottom kiln, and provide heat with drying calcium carbonate powder for moisture eliminator, high-temperature heat-conductive oil temperature through well heater reduces, through condenser cooling, (temperature of the object Shi Shi digestion chamber of cooling reduces again, increase solubleness, improve the speed and efficiency of reacting and carrying out), high-temperature heat-conductive oil temperature reduces, and recycled by recycle pump feeding interchanger.
Calcium sulfate is produced the low temperature exhaust heat in calcium oxide process by the present invention, for the production of the drying of subsequent material in process, the Efficient Cycle finally realizing heat utilizes, calcium sulfate can be avoided to produce the waste of calcium oxide process middle-low temperature heat, reduce energy expenditure more than 10%, increase purity and the production efficiency of product calcium oxide simultaneously.
Accompanying drawing explanation
Fig. 1 is the apparatus embodiments structural representation producing calcium oxide with calcium sulfate of the present invention.
Embodiment
Below in conjunction with drawings and Examples, the present invention is described in further detail.
The equipment producing calcium oxide with calcium sulfate of the present embodiment, comprise calcining kiln 1, digestion chamber 2, secondary clacining kiln 10, described calcining kiln 1 is communicated with digestion chamber 2 its top feed mouth 12 by bottom discharge mouth I 11, and described digestion chamber 2 is divided into two-layer, and centre is separated by 3000 object filter screens I 13; Digestion chamber 2 sidewall is also provided with and passes into pipeline 15 towards the carbonic acid gas bottom digestion chamber 2, the discharge port II 14 of band filter screen II 6 and separating bucket 7 is provided with bottom digestion chamber 2, described filter screen II 6 is incline structure, it is 45 degree with horizontal angle, the lower end of one end that filter screen II 6 is lower and separating bucket 7 mouthfuls maintains an equal level, interchanger 3 is provided with outside digestion chamber 2 wall, separating bucket 7 directly passes in the kiln 8 of open design, described kiln 8 communicates with secondary clacining kiln 10, and described interchanger 3 is formed with well heater 9, condenser 5, recycle pump 4 successively to close by pipeline and is connected; Described well heater 9 is positioned at the bottom of kiln 8; Described filter screen II 6 is 3000 orders.
The equipment work process of producing calcium oxide with calcium sulfate of the present embodiment, the i.e. technique of producing calcium oxide with calcium sulfate of the present embodiment, comprise following two-part step:
Material production process: generation calcium oxide is decomposed in calcium sulfate high-temperature calcination in calcining kiln 1, blended solid powder in calcining kiln 1 is successively by the discharge port I 11 bottom calcining kiln, digestion chamber 2 its top feed mouth 12 enters digestion chamber 2, in digestion chamber 2, digested reaction generates calcium hydroxide to calcium oxide, and produce amount of heat, calcium hydroxide is water-soluble and other impurity is water insoluble, by being positioned at the filtration of 3000 object filter screens I 13 in the middle of digestion chamber, upper strata, digestion chamber 2 is the mixture of calcium hydroxide and impurity, lower floor is aqua calcis, pass into pipeline 15 by the carbonic acid gas of digestion chamber 2 sidewall simultaneously and pass into carbon dioxide in calcium hydroxide aqueous solution, generate precipitation of calcium carbonate, after the filtration of digestion chamber 2 bottom screen II 6, filter screen II 6 top is the calcium carbonate powders containing moisture, calcium carbonate powders containing moisture is transported to kiln 8 through separating bucket 7, filtrate is discharged through discharge port II 14 lower end, calcium carbonate powders is after kiln 8 drying, send into secondary clacining kiln 10 to calcine, the calcium oxide that purity is 99wt% can be obtained.
Recycle heat process: the digestion of digestion chamber 2 calcium oxide can discharge a large amount of heat, be fixed on the interior logical high temperature heat conductive oil of interchanger 3 of digestion chamber 2 outer wall, high temperature heat conductive oil absorbs heat, and flowing is passed to the well heater 9 be positioned at bottom kiln 8, and providing heat with drying calcium carbonate powder for kiln 8, the high-temperature heat-conductive oil temperature through well heater 9 reduces, then cools through condenser 5, high-temperature heat-conductive oil temperature reduces, and sends into interchanger 3 by recycle pump 4 and recycle.
Calcium sulfate is produced the low temperature exhaust heat in calcium oxide process by the present invention, for the production of the drying of subsequent material in process, the Efficient Cycle finally realizing heat utilizes, calcium sulfate can be avoided to produce the waste of calcium oxide process middle-low temperature heat, reduce energy expenditure 12%, increase purity and the production efficiency of product calcium oxide simultaneously.

Claims (5)

1. produce an equipment for calcium oxide with calcium sulfate, comprise calcining kiln, digestion chamber, secondary clacining kiln, described calcining kiln is communicated with digestion chamber's its top feed mouth by bottom discharge mouth I, and described digestion chamber is divided into two-layer, and centre is separated by filter screen I; Digestion chamber's sidewall is also provided with and passes into pipeline towards the carbonic acid gas bottom digestion chamber, the discharge port II of band filter screen II and separating bucket is provided with bottom digestion chamber, described filter screen II is incline structure, be 10-60 degree with horizontal angle, one end that filter screen II is lower maintains an equal level with the lower end being separated quarrel, it is characterized in that, digestion locular wall peripheral hardware has interchanger, separating bucket directly passes in the kiln of open design, described kiln communicates with secondary clacining kiln, and described interchanger is formed with well heater, condenser, recycle pump successively to close by pipeline and is connected; Described well heater is positioned at the bottom of kiln.
2. calcium sulfate according to claim 1 produces the equipment of calcium oxide, it is characterized in that, filter screen II and horizontal angle are 45 degree.
3. calcium sulfate according to claim 1 and 2 produces the equipment of calcium oxide, and it is characterized in that, the order number of described filter screen I and filter screen II is 1500-4000 order.
4. calcium sulfate according to claim 3 produces the equipment of calcium oxide, and it is characterized in that, the order number of described filter screen I and filter screen II is 3000 orders.
5. use a technique for the equipment recovery waste heat producing calcium oxide as described in one of claim 1-4 with calcium sulfate, it is characterized in that, comprise the following steps:
Material production process: generation calcium oxide is decomposed in calcium sulfate high-temperature calcination in calcining kiln, blended solid powder in calcining kiln is successively by the discharge port I bottom calcining kiln, digestion chamber's its top feed mouth enters digestion chamber, in digestion chamber, digested reaction generates calcium hydroxide to calcium oxide, and produce amount of heat, calcium hydroxide is water-soluble and other impurity is water insoluble, by being positioned at 1500-4000 object filter screen I filtration in the middle of digestion chamber, upper strata, digestion chamber is the mixture of calcium hydroxide and impurity, lower floor is aqua calcis, pass into pipeline by the carbonic acid gas of digestion chamber's sidewall simultaneously and pass into carbon dioxide in calcium hydroxide aqueous solution, generate precipitation of calcium carbonate, after the filtration of digestion chamber's bottom screen II, filter screen II top is the calcium carbonate powders containing moisture, calcium carbonate powders containing moisture is transported to kiln through separating bucket, filtrate is discharged through discharge port II lower end, calcium carbonate powders is after kiln drying, send into the calcining of secondary clacining kiln, the calcium oxide that purity is higher can be obtained,
Recycle heat process: the digestion of digestion chamber's calcium oxide can discharge a large amount of heat, the high temperature heat conductive oil of logical flash-point >=320 DEG C in the interchanger being fixed on digestion chamber's outer wall, high temperature heat conductive oil absorbs heat, and flowing is passed to the well heater be positioned at bottom kiln, and providing heat with drying calcium carbonate powder for moisture eliminator, the high-temperature heat-conductive oil temperature through well heater reduces, then cools through condenser, high-temperature heat-conductive oil temperature reduces, and is recycled by recycle pump feeding interchanger.
CN201210564848.8A 2012-12-24 2012-12-24 Equipment and technology of calcium oxide producing with calcium sulfate Active CN103058245B (en)

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Publication number Priority date Publication date Assignee Title
CN110590193B (en) * 2019-11-04 2023-04-14 建德市泰合新材料有限公司 High-purity calcium oxide calcining kiln car
CN117123031B (en) * 2023-08-25 2024-05-24 宁可益(云南)环境科技有限责任公司 Carbon fixing structure

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1109024A (en) * 1994-03-19 1995-09-27 颜寿地 Method and apparatus for producing lightweight calcium carbonate
WO2004087601A1 (en) * 2003-02-24 2004-10-14 Posco METHOD AND BURNER APPARATUS FOR INJECTING A PULVERIZED COAL INTO ROTARY KILNS, METHOD AND APPARATUS FOR PRODUCING CaO USING THEM
CN1644507A (en) * 2004-12-16 2005-07-27 山东海化集团有限公司 Production of light calcium carbonate
RU2367604C1 (en) * 2008-01-09 2009-09-20 Государственное образовательное учреждение высшего профессионального образования Дальневосточный государственный технический университет (ДВПИ им. В.В. Куйбышева) Method for treatment of carbon-carbonate mineral raw materials
CN202968147U (en) * 2012-12-24 2013-06-05 刘立文 Equipment for producing calcium oxide through calcium sulfate

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1109024A (en) * 1994-03-19 1995-09-27 颜寿地 Method and apparatus for producing lightweight calcium carbonate
WO2004087601A1 (en) * 2003-02-24 2004-10-14 Posco METHOD AND BURNER APPARATUS FOR INJECTING A PULVERIZED COAL INTO ROTARY KILNS, METHOD AND APPARATUS FOR PRODUCING CaO USING THEM
CN1644507A (en) * 2004-12-16 2005-07-27 山东海化集团有限公司 Production of light calcium carbonate
RU2367604C1 (en) * 2008-01-09 2009-09-20 Государственное образовательное учреждение высшего профессионального образования Дальневосточный государственный технический университет (ДВПИ им. В.В. Куйбышева) Method for treatment of carbon-carbonate mineral raw materials
CN202968147U (en) * 2012-12-24 2013-06-05 刘立文 Equipment for producing calcium oxide through calcium sulfate

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Effective date of registration: 20160823

Address after: An Industrial Park Economic Development Zone, Changde City, Hunan province Linli County 415200

Patentee after: Hunan Fu Xiang new type building material Co., Ltd.

Address before: 410005, 12 floor, Haidong mansion, Furong Road, Changsha, Hunan

Patentee before: Liu Liwen