CN102092751B - Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization - Google Patents

Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization Download PDF

Info

Publication number
CN102092751B
CN102092751B CN 201010554860 CN201010554860A CN102092751B CN 102092751 B CN102092751 B CN 102092751B CN 201010554860 CN201010554860 CN 201010554860 CN 201010554860 A CN201010554860 A CN 201010554860A CN 102092751 B CN102092751 B CN 102092751B
Authority
CN
China
Prior art keywords
chloride hexahydrate
aluminum chloride
aluminum oxide
hydrochloric acid
crystallization
Prior art date
Application number
CN 201010554860
Other languages
Chinese (zh)
Other versions
CN102092751A (en
Inventor
何建祥
魏超
杨扬
Original Assignee
西安三瑞实业有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 西安三瑞实业有限公司 filed Critical 西安三瑞实业有限公司
Priority to CN 201010554860 priority Critical patent/CN102092751B/en
Publication of CN102092751A publication Critical patent/CN102092751A/en
Application granted granted Critical
Publication of CN102092751B publication Critical patent/CN102092751B/en

Links

Abstract

The invention provides a method for preparing aluminum oxide and co-producing hydrochloric acid from crystallized aluminum chloride hexahydrate through pyrolysis crystallization. The method comprises the following steps: sending crystallized aluminum chloride hexahydrate used as a raw material to a pyrolyzing furnace to perform intramolecular dehydration and thermal cracking reaction at 140-900 DEG C and generate the product-aluminum oxide, and using a tail gas treatment system to absorb pyrolytic tail gas and generate the hydrochloric acid byproduct. By adopting the method in the invention, the comprehensive utilization industrial chain of fly ash can be extended, the environmental pollution problem that a lot of fly ash is stored up can be solved, strategic metal resources can be effectively recycled and great economic benefits can be created. The technological process in the invention has the single reactant, concise and clear main process, adequate and stable raw material supply and low production cost; and the emission of three wastes reaches the standard completely, the method in the invention belongs to the comprehensive utilization project of resources and meets the national industrial policy.

Description

A kind of pyrolysis crystallization Aluminum Chloride Hexahydrate is produced the method for aluminum oxide and by-product hydrochloric acid

Technical field

The present invention relates to a kind ofly make the crystallization Aluminum Chloride Hexahydrate at high temperature decompose to obtain the method for higher-grade aluminium sesquioxide and by-product hydrochloric acid by calcining.

Background technology

Crystallization Aluminum Chloride Hexahydrate (or claiming crystal aluminum chloride, Aluminum Chloride Hexahydrate) molecular formula is AlCl 36H 2O, a kind of product that obtains for the aluminum chloride aqueous solution condensing crystal, can be used as water treatment agent, casting stiffening agent, wood preservative, paper-making sizing precipitation agent etc., in addition, the crystallization Aluminum Chloride Hexahydrate can be used for also that wool is refining, production, polymerize aluminum chloride production and the medicine industry etc. of aluminum hydroxide gel production, oil chlorination cracking catalyst monomer.

Comprehensive utilization flyash or coal gangue can reclaim wherein the aluminium form with the crystallization Aluminum Chloride Hexahydrate, flyash is as fuel take coal, receive the thin ash catch from flue gas, its content accounts for 5%~20% of coal-fired total amount, one of main solid waste of discharging for the coal-burning power plant.

Utilize research and the production status of the further production derived product of crystallization Aluminum Chloride Hexahydrate mostly to be at present production polymerize aluminum chloride etc., produce the alumina product that can be used for electrolysis of aluminum and in pertinent literature, rarely have report.

Aluminum oxide (or claiming aluminium sesquioxide, alumina) molecular formula is Al 2O 3, can be used as abrasive, aluminium metallurgy raw material, and for the manufacture of the products such as aluminium hydroxide of crucible, porcelain, refractory materials, hard mass, different crystal forms.

Along with the Application Areas of aluminium and alloy product thereof is increasingly extensive, the situation that supply falls short of demand appears continuing in metallic aluminium market, for the imbalance between supply and demand of alleviating the aluminum metal resource, optimize the structure of production, for different character raw materials, use multiple recovery method, select that flexibly product form comprehensive utilization is various to contain bauxite resource and waste is imperative.

Summary of the invention

The purpose of this invention is to provide the method that a kind of pyrolysis crystallization Aluminum Chloride Hexahydrate is produced aluminum oxide and passed through the tail gas absorbing system by-product hydrochloric acid.

The production method of aluminum oxide of the present invention and hydrochloric acid comprises the following steps:

(1) AlCl 36H 2O (crystallization Aluminum Chloride Hexahydrate) delivers to the raw material feed bin, by sending into calcining furnace after the metering, temperature of charge is at 140~900 ℃ of lower reaction 30min~180min, and thermo-cracking obtains aluminum oxide, hydrogenchloride and water vapour, keep little positive/negative-pressure in the rotary reaction furnace, force value is controlled at 50~-50mmH 2O.

(2) alumina product is discharged body of heater from the calcining furnace tail, is cooled to 50~120 ℃ through cooling apparatus, sends into subsequent processing or is packaged as the finished product aluminum oxide; The hydrogenchloride that reaction generates and water vapour cool off, absorb the hydrochloric acid of by-product technical grade through dedusting; Do not absorb completely HCl tail gas and enter the absorption that neutralizes of alkali cleaning equipment and sig water, realize qualified discharge.

The main chemical reactions equation is as follows:

2AlCl 3·6H 2O→Al 2O 3+9H 2O+6HCl

HCl+NaOH→NaCl+H 2O

The present invention has extended the industrial chain of total utilization of PCA, has not only solved the problem of environmental pollution that flyash is stored up in a large number, and efficient recovery strategy metal resource, can create huge economic benefit.The hydrochloric acid of this technique by-product can reach the technical grade standard, and the reaction acid as Aluminum Chloride Hexahydrate in the flyash refines reaches the recycle of resource.

This project technological process reactant is single, main technique simple and clear, and raw material supply is sufficient stable, low production cost, " three wastes " are qualified discharge all, belongs to the comprehensive utilization of resources project, meets the industry policy that country advocates.

Description of drawings

Fig. 1 is the pyrolytic process schema.

Fig. 2 is the vent gas treatment schema.

Embodiment

A kind of pyrolysis crystallization Aluminum Chloride Hexahydrate of the present invention produces aluminum oxide and the embodiment by the tail gas absorbing system by-product hydrochloric acid comprises:

(1) the crystallization Aluminum Chloride Hexahydrate is delivered to the raw material feed bin, by sending into calcining furnace after the metering.Can select any commercially available prod for the material crystal Aluminum Chloride Hexahydrate, preferred, use the total utilization of PCA product; Can select the methods well known in the art such as quantitative conveying feeding machine, Weightlessness balance, weighing belt for metering method, preferred, use weighing belt to measure; Can select method well known in the art for carrying method, preferred, use worm conveyor to carry.

(2) the crystallization Aluminum Chloride Hexahydrate after will measuring is sent into calcining furnace, temperature of charge is at 140~900 ℃ of lower reaction 30min~180min, thermo-cracking obtains aluminum oxide, hydrogenchloride and water vapour, keeps little positive/negative-pressure in the rotary reaction furnace, and force value is controlled at 50~-50mmH 2O.For calciner, can select vertical calcining furnace, rotary calcining stove, oscillatory type calcining furnace, tunnel like calcining furnace etc., preferred, use the rotary calcining stove.For the calciner type of heating, can select external-heat or internal heat type.

The main chemical reactions equation is as follows:

2AlCl 3·6H 2O→Al 2O 3+9H 2O+6HCl

(3) alumina product is discharged body of heater from the calcining furnace tail, is cooled to 50~120 ℃ through cooling apparatus, sends into subsequent processing or is packaged as the finished product aluminum oxide.The discharging carrying method can be selected method well known in the art, and is preferred, uses worm conveyor to carry out discharging.

(4) hydrogenchloride of reaction generation and water vapour are at first removed the dust in the gas, through cooling off and partially absorbing, and after absorbing via two-stage HCl resorber again, by-product hydrochloric acid.For dust removal installation, can select the equipment well known in the art such as gravity settling chamber, sack cleaner, electric dust-catching and cleaning equipment, preferred, use tornado dust collector or strainer to carry out dedusting; For cooling and absorbing equipment, can select equipment well known in the art, preferred, use tower to carry out cooling and absorbing; For follow-up absorption equipment, can select equipment well known in the art, preferred, use graphite falling film absorber.

(5) unabsorbed HCl tail gas enters the absorption that neutralizes of alkali cleaning equipment and sig water, realizes qualified discharge.For alkali cleaning equipment, can select equipment well known in the art, preferred, use tower; For alkali lye, can select material well known in the art, preferred, use sodium hydroxide.

The main chemical reactions equation is as follows:

HCl+NaOH→NaCl+H 2O

There is no particular restriction in the present invention for employed material crystal Aluminum Chloride Hexahydrate, preferentially selects the total utilization of PCA product, and the present invention is applicable to any commercially available crystallization Aluminum Chloride Hexahydrate product too.The granularity of Aluminum Chloride Hexahydrate can be 0.2~1.2mm, and the granularity of preferred Aluminum Chloride Hexahydrate is 0.3~0.8mm, and the granularity of preferred Aluminum Chloride Hexahydrate is 0.3~0.5mm.For the purity of Aluminum Chloride Hexahydrate, be preferably 85% or higher, preferred purity is 95% or higher, most preferred purity is 98% or higher.

See also Fig. 1, the crystallization Aluminum Chloride Hexahydrate is sent into and is carried out pyrolysis in the rotary kiln, pyrolysis is temperature required to be provided by hot-air system, hot blast conducts heat by outer wall to be provided heat or directly brings rotary kiln into by the inertia heat-carrying gas in stove, can obtain meeting from the stove tail alumina product of relevant criterion after the calcining, tail gas send tail gas absorbing system through after the dedusting.

See also Fig. 2, pyrolysis tail gas at first by quenching column via from the absorption liquid high efficiency cooling of hydrogenchloride one-level resorber and partially absorb, absorption liquid is sent into the dilute hydrochloric acid storage tank, tail gas enters hydrogenchloride one-level resorber again and is partially absorbed by the absorption liquid from the hydrogenchloride secondary absorber, enter again the hydrogenchloride secondary absorber and partially absorbed by the absorption liquid from scrubber tower, enter again scrubber tower and partially absorb the rear soda-wash tower that finally enters by process water and realize qualified discharge after by alkali liquor absorption.

Embodiment 1

(1) takes by weighing 40kg crystallization Aluminum Chloride Hexahydrate and deliver to crystallization Aluminum Chloride Hexahydrate feed bin through handling equipment, in feed bin, by valve powder material is entered in the weighing belt after the accurate measurement, send in the lower elephant trunk, send into the feed auger of crystallization Aluminum Chloride Hexahydrate calcining furnace by blanking device, feed auger is sent into material in the crystallization Aluminum Chloride Hexahydrate calcining furnace and is calcined.

Material crystal Aluminum Chloride Hexahydrate bulk density is 0.819g/cm 3, particle size range 0.6~1.2mm, main chemical constitution is as shown in the table:

Component ??AlCl 3.6H 2O ??KCl ??NaCl ??CaCl 2.2H 2O ??H 2O Content ??93~95% ??0.05~0.1% ??0.05~0.1% ??0.1~0.5% ??3~5%

(2) the calcining furnace type of heating is taked external-heat, and the external heat air temperature is controlled between 850~1050 ℃, and temperature of charge is at 650~850 ℃ in the stove.The crystallization Aluminum Chloride Hexahydrate carries out interior dehydration and heat scission reaction in calcining furnace, the residence time of material in calcining furnace is about 60min, the reaction product aluminum oxide enters the feed box of calcining furnace, by star-shaped feeder continuous aluminum oxide is sent into cooler by elephant trunk, be cooled to about 80 ℃, collect altogether approximately 8.42kg of alumina product.

Transformation efficiency through calculating crystallization Aluminum Chloride Hexahydrate is 99.608%, pyrolysis gained alumina product particle size range 178~420 μ m, and bulk density is 0.464g/cm 3.

(3) hydrogen chloride gas and the water vapour that generate of heat scission reaction at first enters tornado dust collector, removes most dust in the gas, and then enters strainer and remove remaining dust.Gas after the dedusting is sent into next operation and is absorbed.

In the whole dust removal process, gas temperature remains on more than 180 ℃, generates hcl corrosion equipment and pipeline to prevent hydrogen chloride gas and vapor dew.Whole system pressure maintains-moves under little condition of negative pressure of 200Pa, and the negative pressure of system is provided by the negative-pressure air fan of follow-up system, ensures in the operational process that sour gas does not leak.

(4) calcination system institute heat requirement is all provided by hot air circulating system.Heavy oil directly enters the passage between body of heater and the chuck after fully burning in roasting kiln, body of heater is carried out radiation and convective heating simultaneously.

Embodiment 2

(1) takes by weighing 40kg crystallization Aluminum Chloride Hexahydrate and deliver to crystallization Aluminum Chloride Hexahydrate feed bin through handling equipment, in feed bin, by valve powder material is entered in the weighing belt after the accurate measurement, send in the lower elephant trunk, send into the feed auger of crystallization Aluminum Chloride Hexahydrate calcining furnace by blanking device, feed auger is sent into material in the crystallization Aluminum Chloride Hexahydrate calcining furnace and is calcined.

Material crystal Aluminum Chloride Hexahydrate bulk density is 0.819g/cm 3, particle size range 0.3~0.5mm, main chemical constitution is as shown in the table:

Component ??AlCl 3.6H 2O ??KCl ??NaCl ??CaCl 2.2H 2O ??H 2O Content ??93~95% ??0.05~0.1% ??0.05~0.1% ??0.1~0.5% ??3~5%

(2) the Sweet natural gas heat-carrying high-temperature gas that produces that burns in roasting kiln enters in the stove from rotary kiln stove tail, and move to the stokehold, the thermograde that formation is successively decreased from the stove tail to burner, temperature of reaction is controlled between 850~1050 ℃, the crystallization Aluminum Chloride Hexahydrate raw material that enters calcining furnace constantly moves to the body of heater back segment in stove, carry out interior dehydration and heat scission reaction, the residence time of material in calcining furnace is about 70min.The reaction product aluminum oxide enters the feed box of calcining furnace, by blanking device continuous aluminum oxide is sent into cooler by elephant trunk, be cooled to about 70 ℃, collect altogether approximately 8.43kg of alumina product.

Transformation efficiency through calculating crystallization Aluminum Chloride Hexahydrate is 99.80%, pyrolysis gained alumina product particle diameter 〉=45 μ m.

(3) hydrogen chloride gas and water vapour that the hot blast after temperature reduces and heat scission reaction generate at first enter tornado dust collector, remove most dust in the gas, and then enter strainer and remove remaining dust.Gas after the dedusting is sent into next operation and is absorbed after further removing outer other water-soluble gas of hydrogenchloride.

In the whole dust removal process, gas temperature remains on more than 180 ℃, generates hcl corrosion equipment and pipeline to prevent hydrogen chloride gas and vapor dew.Whole dust-removal system is moved under little condition of negative pressure of-300Pa, and the negative pressure of system is provided by the negative-pressure air fan of follow-up system, ensures in the operational process that sour gas does not leak.

(4) the hot cigarette wind that produces after by Sweet natural gas perfect combustion of calcination system institute heat requirement provides.

Above method to pyrolysis crystallization Aluminum Chloride Hexahydrate production aluminum oxide provided by the present invention is described in detail.Used specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof.Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention, can also carry out some improvement and modification to the present invention, these improvement and modification also fall in the protection domain of claim of the present invention.

Claims (1)

1. a pyrolysis crystallization Aluminum Chloride Hexahydrate is produced the method for aluminum oxide and by-product hydrochloric acid, it is characterized in that with particle size range being that 0.2~1.2mm and purity are delivered to the raw material feed bin more than or equal to 95% crystallization Aluminum Chloride Hexahydrate, by sending into the rotary calcining stove after the metering, temperature of charge is at 600~850 ℃ of lower reaction 30min~180min, thermo-cracking obtains aluminum oxide, hydrogenchloride and water vapour, keep little positive/negative-pressure in the rotary calcining stove, force value is controlled at 50~-50mmH 2O; Rotary calcining stove type of heating is selected external-heat; Aluminum oxide is discharged body of heater from rotary calcining stove tail, is cooled to 50~120 ℃ through cooling apparatus, sends into subsequent processing or is packaged as the finished product aluminum oxide; The hydrogenchloride that reaction generates and water vapour are through dedusting, cooling, absorption, the hydrochloric acid of by-product technical grade; Do not absorb completely hydrogen chloride tail gas and enter the absorption that neutralizes of alkali cleaning equipment and sig water, realize qualified discharge.
CN 201010554860 2010-11-19 2010-11-19 Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization CN102092751B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 201010554860 CN102092751B (en) 2010-11-19 2010-11-19 Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 201010554860 CN102092751B (en) 2010-11-19 2010-11-19 Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization

Publications (2)

Publication Number Publication Date
CN102092751A CN102092751A (en) 2011-06-15
CN102092751B true CN102092751B (en) 2013-04-03

Family

ID=44126042

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 201010554860 CN102092751B (en) 2010-11-19 2010-11-19 Method for preparing aluminum oxide and co-producing hydrochloric acid from aluminum chloride hexahydrate through pyrolytic crystallization

Country Status (1)

Country Link
CN (1) CN102092751B (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104730210A (en) * 2013-12-24 2015-06-24 贵阳铝镁设计研究院有限公司 Testing device for extracting aluminum oxide from aluminum chloride crystal
CN104058436B (en) * 2014-06-12 2016-06-01 北京航天动力研究所 A kind of rotary kiln baking six water crystallization aluminum chloride prepares the device and method of aluminum oxide
CN105084400A (en) * 2015-09-18 2015-11-25 东北大学 Device and method for preparing activated aluminum oxide
CN106241845B (en) * 2016-08-29 2017-12-22 何顺爱 A kind of ultrapure ball-aluminium oxide powder preparation method
CN108002416B (en) * 2017-11-27 2019-04-26 沈阳东大东科干燥煅烧工程技术有限公司 A kind of drying and calcining processing technology and equipment crystallizing Aluminum Chloride Hexahydrate
CN108862344A (en) * 2018-07-27 2018-11-23 东北大学 A kind of method of the crystal aluminum chloride preparing alumina by hydrolysis of controllable crystal form

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101234774A (en) * 2008-03-04 2008-08-06 华东理工大学 Method for preparing aluminum oxide from coal series kaolinite rock or coal gangue
CN101450811A (en) * 2008-10-23 2009-06-10 长春市超威新材料科技有限公司 Method for extracting alumina from coal gangue
CN201508106U (en) * 2009-09-04 2010-06-16 西安三瑞实业有限公司 Rotary calciner for producing alumina
CN101811712A (en) * 2010-04-27 2010-08-25 中国神华能源股份有限公司 Method for preparing metallurgical-grade aluminum oxide by using fluid-bed fly ash
CN101838000A (en) * 2010-04-27 2010-09-22 中国神华能源股份有限公司 Method for producing metallurgical aluminum oxide by using iron-containing solution of aluminum chloride

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101234774A (en) * 2008-03-04 2008-08-06 华东理工大学 Method for preparing aluminum oxide from coal series kaolinite rock or coal gangue
CN101450811A (en) * 2008-10-23 2009-06-10 长春市超威新材料科技有限公司 Method for extracting alumina from coal gangue
CN201508106U (en) * 2009-09-04 2010-06-16 西安三瑞实业有限公司 Rotary calciner for producing alumina
CN101811712A (en) * 2010-04-27 2010-08-25 中国神华能源股份有限公司 Method for preparing metallurgical-grade aluminum oxide by using fluid-bed fly ash
CN101838000A (en) * 2010-04-27 2010-09-22 中国神华能源股份有限公司 Method for producing metallurgical aluminum oxide by using iron-containing solution of aluminum chloride

Also Published As

Publication number Publication date
CN102092751A (en) 2011-06-15

Similar Documents

Publication Publication Date Title
CN102061350B (en) Short-process comprehensive red mud utilization method and equipment
CN104556036A (en) Method for preparing solid calcium carbide
CN102297566B (en) Production method for drying and upgrading lignite
CN103980912B (en) A kind of brown coal method for destructive distillation and device
CN103421525B (en) A kind of low-rank coal method for upgrading and system
CN101726167B (en) Smoke semi-closed circulating lignite straight pipe type airflow drying method
CN102942943B (en) Oil shale gas-solid heat carrier dry distillation and semicoke combustion electricity generation integral process
CN101234762B (en) Physical method energy-saving cleaning technique for manufacturing active carbon
US10005669B2 (en) Method for mass production of phosphoric acid with rotary kiln
CN101597658B (en) Coal gasification system and method of blast furnace slags
CN203144295U (en) Heat accumulating type dividing-wall heating rotary lime kiln
CN102965170B (en) Energy-conserving and environment-protective brown coal briquette preparation technology and system
CN202008279U (en) Material drying tower, material drying system and coking coal humidifying system
CN202465830U (en) Residual heat reclaiming system for pellets and sintered ores
CN103304157B (en) Energy-conservation and emission-reduction type active lime calcination method and apparatus
CN102442650B (en) Method for producing sulfuric acid and co-producing calcium carbide by phosphogypsum
CN103708515B (en) A kind of is that raw material adopts predecomposition explained hereafter α-Al with aluminium hydroxide 2o 3method
CN201598180U (en) Calcium carbide furnace discharging cooling system
JP2018538445A (en) Recovery of lithium from silicate minerals
CN102417822A (en) Method for performing solid heat carrier pyrolysis on coal by using self-return revolving furnace
CN101580727A (en) Cleaning, pyrolysis and oil extracting methods of low-rank coal by internal heat rolling bed
CN204824725U (en) High -efficient, prevent chute blockage and carry matter gyration reacting furnace
CN102363837B (en) A kind of powdery manganese oxide ore fluidization low-temperature reduction method
CN202203950U (en) Organic solid waste pyrolyzation and gasification device
CN103776270A (en) Calcium carbide sensible heat recovery equipment and method for calcium carbide furnace

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model