CN209128054U - A kind of titanium dioxide calcining dry method dust collecting system - Google Patents

Abstract

The utility model discloses a kind of titanium dioxides to calcine dry method dust collecting system, belong to field of titanium dioxide production, its key points of the technical solution are that, including sequentially connected pretreatment unit, calcine pretreating device, calcine dust-extraction unit and calcining after-treatment device, calcining dust-extraction unit includes rotary kiln, the rotary kiln is connected with dry collector, the dry collector includes cabinet, air inlet, air outlet, injection tube, the ash bucket of filter core and back taper, the filter core by stainless steel fibre felt at, the ash bucket lower end is connected with horizontally disposed conveying equipment, the conveying equipment includes feeding pipe and the spiral feeding shaft that is installed in feeding pipe, the spiral conveying axis connection has driving motor.The utility model is collected suitable for high-temp waste gas defective material.

Description

A kind of titanium dioxide calcining dry method dust collecting system

Technical field

The utility model relates to dry method to gather dust, in particular to a kind of titanium dioxide calcines dry method dust collecting system.

Background technique

Titanium dioxide, i.e. titanium dioxide are a kind of important inorganic chemical products, coating, ink, papermaking, plastic, rubber, There is important use in the industry such as chemical fibre, ceramics.The production method of titanium dioxide has sulfuric acid process and two kinds of chloridising, the former material of sulfuric acid process Expect cheap, production technology is more mature, but production procedure is long and the discharge amount of the three wastes is larger；The production process of chloridising The deficiencies of more environmentally friendly, product quality is relatively high, big but there is also up-front investments, and the device is complicated and product is single.At present The titanium white production of China 90% still uses Production By Sulfuric Acid Process.

In the actual production process, it is needed hydrated titanium dioxide in sulfuric acid process in 900 DEG C of -1250 DEG C of temperature lower calcinations, Remove moisture removal and remaining sulfur trioxide, calcination stage can generate exhaust gas, in addition to sulfur trioxide and sulfuric acid mist in exhaust gas, also deposit In some subtle titanium dioxide granules.Titanium dioxide granule in exhaust gas can remove grinding from and be directly entered subsequent handling High quality titanium dioxide granule, and need for exhaust gas to be passed through Venturi scrubber in traditional handicraft and carry out gas washing, titanium dioxide Grain is difficult to recycle after mixing with liquid, causes the waste of material.

Utility model content

The purpose of the utility model is to provide a kind of titanium dioxides to calcine dry method dust collecting system, has and improves titanium dioxide unit original The advantages of expecting yield.

The above-mentioned technical purpose of the utility model has the technical scheme that

A kind of titanium dioxide calcines dry method dust collecting system, including sequentially connected pretreatment unit, calcining pretreating device, forges Burning dust cleaning apparatus and calcining after-treatment device, calcining dust-extraction unit includes rotary kiln, and the rotary kiln is connected with dry collector, The dry collector includes the ash bucket of cabinet, air inlet and outlet, injection tube, filter core and back taper, and the filter core is by stainless Steel fibre felt is at being connected with horizontally disposed conveying equipment, the conveying equipment between the ash bucket lower end and encapsulation tool Including feeding pipe and the spiral feeding shaft being installed in feeding pipe, the spiral conveying axis connection has driving motor.

By using above-mentioned technical proposal, the ore raw materials for making titanium dioxide is generated in pretreatment unit with sulfuric acid reaction First peptide liquid, and the titanium liquid required for normal concentration is concentrated.Peptide liquid first passes through reactor in high temperature ring in processing unit before calcination Reaction generates metatitanic acid in border, and metatitanic acid is by removal of impurities and salt treatment process, and finally squeezing forms filter cake in filter cake molding machine, Filter cake enters the calcining of rotary kiln high temperature, and the reaction of dehydration, desulfurization, crystalline transformation and grain growth occurs in rotary kiln for filter cake Enter calcining after-treatment device afterwards, the physical characteristic of the titanium dioxide formed after calcining is poor, and there are a large amount of aggregation and burnings Knot body needs to crush by grinding machine, then improves physics and chemical characteristic through encapsulation tool, most afterwards through flashing apparatus expansion drying Become qualified titanium dioxide product afterwards.When filter cake is calcined in rotary kiln, it can generate largely useless containing titanium dioxide dust Gas, the exhaust gas of calcined by rotary kiln output is generally at 400 DEG C or more, and the sulfuric acid components mixed in process containing before, dry type are removed Dirt device select stainless steel fibre felt made of filter core, can the exhaust gas directly to high temperature and highly corrosive be dusted, reduce Cooling process to be carried out in advance to exhaust gas in traditional handicraft, it is possible to reduce the use of cooling equipment, reduction are set in traditional handicraft Standby whole occupied area simultaneously reduces economic cost.Meanwhile the titanium dioxide dust in exhaust gas granular size meet directly into Enter the requirement of encapsulation tool, injection tube sprays compressed air and blows off the dust for being attached to cartridge surface into ash bucket, and conveying is set Standby can directly be conveyed into the titanium dioxide dust in ash bucket in encapsulation tool is handled, and reduces the waste of product simultaneously Improve the unit raw material output of titanium dioxide.

Further, it is equipped in the ash bucket and forces to fall grey structure, it includes that shaft and shaft are solid that the pressure, which falls grey structure, Surely the cross bar connected and the scraper plate positioned at cross bar both ends, the scraper plate are abutted with the inner surface of ash bucket, and the shaft passes through cone tooth The connection of the output end of wheel group and driving motor.

By using above-mentioned technical proposal, titanium dioxide dust may bond in ash bucket inner surface and lead to specific yield Decline, pressure, which falls grey structure, can scrape the titanium dioxide dust of ash bucket inner surface and collect into conveying equipment, reduce The waste of material.It forces the setting for falling grey structure and conveying equipment common drive motor that can also save equipment to be taken up space.

Further, buffering pipe is equipped between the ash bucket lower end and conveying equipment, the shaft surface is located at buffering Pipeline inner part is fixedly connected with spice impeller.

By using above-mentioned technical proposal, buffering pipe can be played temporarily the titanium dioxide dust for entering conveying equipment The effect of storage, in deduster titanium dioxide dust fall collection be it is interim, be easy to cause material heap in conveying equipment Product is excessive and damages driving motor, and buffering pipe may be implemented material and at the uniform velocity supply in conveying equipment, to protect driving electricity Machine.The setting of spice impeller also may make that titanium white powder particles are further stirred, so that titanium white powder particles blanking is more equal It is even, it is not easy to deposit.

Further, the titanium dioxide calcining dry method dust collecting system includes waste liquid concentrator, the waste liquid concentrator It is connect between the air outlet of dry collector by level-one return air duct.

By using above-mentioned technical proposal, it is useless that a large amount of sulfuric acid can be generated during manufacturing titanium dioxide using sulfuric acid process Liquid in sulfuric acid waste and will generate laterite in traditional handicraft, and a large amount of laterite, which exists, to be taken up a large area and reluctant problem, This titanium dioxide calcines dry method dust collecting system by the way of waste liquid concentration, directly can be concentrated waste liquid high temperature to form sulphuric acid production Object recycles reaction material, more environmentally-friendly.It is Celsius that the exhaust gas temperature of dry collector air outlet can reach 200 Degree or more, heat contained in exhaust gas belongs to low-quality thermal energy, therefore portion is passed through in waste liquid concentrator, on the one hand Sulfuric acid components in exhaust gas can be dissolved in the yield that waste liquid concentration is improved in waste liquid, it on the other hand can be to waste liquid concentrator It is preheated, reduces the energy loss that external heating generates in concentration process.

Further, the rotary kiln includes kiln hood, and the air outlet of the dry collector and the kiln hood of rotary kiln pass through The connection of second level return air duct.

By using above-mentioned technical proposal, the exhaust gas of air outlet can preheat kiln hood, reduce and calcine combustion in rotary kiln The usage amount of material, while the entrance of exhaust gas also has the function of tonifying Qi, and more air can be made to participate in calcination process, Improve burning quality.

Further, the second level return air duct is equipped with volume control damper, and the second level return air duct is at kiln hood Equipped with airflow meter.

By using above-mentioned technical proposal, the adjustable exhausted air quantity into rotary kiln of setting of volume control damper, work Personnel can adjust volume control damper according to calcining demand, so that air compensation rises or falls, to further increase rotary kiln Interior burning quality.

Further, the air inlet of the dry collector is equipped with level-one temperature measurer, is equipped with second level at the air outlet Temperature measurer, the level-one temperature measurer and second level temperature measurer are electrically connected with PLC controller.

By using above-mentioned technical proposal, level-one temperature measurer and second level temperature measurer can be respectively to before calcining and calcined Exhaust gas temperature is monitored, if the not up to defined standard of exhaust gas temperature, refers to for operator to deposit in discovering device The problem of.In addition, sulfuric acid solution is vaporized in 230 degrees centigrades, therefore is wanted due in the method for the production titanium dioxide Guarantee that minimum temperature in dust removal process, i.e. temperature at air outlet are higher than 230 degrees Celsius, filter core can be effectively reduced and other are dry Formula dust remover component receives the degree of corrosion, extends dry collector service life.The setting of PLC controller can make exhaust gas When temperature is lower than standard value, automatic control equipment is shut down, and reduces the damage that dry collector is subject to, and operator is facilitated to overhaul Maintenance.

Further, the air inlet of the dry collector is equipped with level-one air gauge, is equipped with second level at the air outlet Air gauge, the level-one air gauge and second level air gauge are electrically connected with PLC controller, the PLC controller and injection tube electricity Connection.

By using above-mentioned technical proposal, when gas reaches air outlet from the air inlet of dry collector, can through filtration core, The Dust Capacity of filter core its surface aggregation in dust removal process can be continuously increased, so that resistance when gas is through filtration core increases Greatly, the air pressure at air outlet is caused to reduce.It is critical as defined in reaching when the draught head between level-one air gauge and second level air gauge When value, then show that the dust saved bit by bit on filter core is excessive and has influenced proper flow of the gas in deduster.PLC at this time Controller receives signal and controls injection tube starting blowing, and the dust on filter core is blown off into ash bucket.

In conclusion the utility model has the following beneficial effects:

1. passing through the setting of dry collector and conveying equipment, can play the titanium dioxide granule recycling in exhaust gas again The effect utilized；

2. passing through the setting of level-one return air duct and second level return air duct, can play the heat recovery in exhaust gas is sharp again Effect；

3. passing through the setting of level-one temperature measurer, second level temperature measurer and PLC controller, real-time monitoring dust removal process can be played In exhaust gas temperature to extend dry collector service life effect.

Detailed description of the invention

Fig. 1 is the process flow diagram that titanium dioxide manufactures in the present embodiment, before embodying pretreatment unit, calcining It manages device, calcining dust-extraction unit and calcines the connection relationship between after-treatment device；

Fig. 2 is the overall structure diagram of dry method dust collecting system in the present embodiment, and for embodying rotary kiln, waste liquid concentration is set Connection relationship between standby, dry collector and conveying equipment；

Fig. 3 is the integrally-built diagrammatic cross-section of dry method dust collecting system in the present embodiment, for embody dry collector and The internal structure of conveying equipment；

Fig. 4 is the enlarged diagram in the portion A in Fig. 3, for embody shaft, cross bar, scraper plate, spice impeller and bevel gear set it Between connection relationship.

In figure, 1, pretreatment unit；11, air swept mill；12, acidification reaction pond；13, settling tank；14, disk filter；15, Inspissator；2, pretreating device is calcined；21, reactor；22, Primary diaphragm filter press；23, bleaching machine；24, secondary diaphragm filters pressing Machine；25, salt treatment furnace；26, filter cake molding machine；3, dust-extraction unit is calcined；31, rotary kiln；311, kiln hood；312, second level backwind tube Road；313, volume control damper；314, airflow meter；32, dry collector；321, cabinet；322, air inlet；3221, level-one thermometric Instrument；3222, level-one air gauge；323, air outlet；3231, second level temperature measurer；3232, second level air gauge；324, spray head；325, it filters Core；326, ash bucket；327, buffering pipe；33, conveying equipment；331, feeding pipe；332, spiral feeding shaft；333, driving electricity Machine；34, PLC controller；4, after-treatment device is calcined；41, waste liquid concentrator；411, level-one return air duct；5, it forces to fall ash Structure；51, shaft；511, cross bar；512, scraper plate；513, spice impeller；52, bevel gear set.

Specific embodiment

The utility model is described in further detail below in conjunction with attached drawing.

Wherein identical components are presented with like reference characters.It should be noted that word used in the following description Language "front", "rear", "left", "right", "up" and "down" refer to the direction in attached drawing, word " bottom surface " and " top surface ", "inner" and "outside" refers respectively to the direction towards or away from geometric center of specific component.

Embodiment: a kind of titanium dioxide calcining dry method dust collecting system, as shown in Figure 1, including sequentially connected pretreatment unit 1, pretreating device 2, calcining dust-extraction unit 3 and calcining after-treatment device 4 are calcined, pretreatment unit 1 includes sequentially connected wind Sweep mill 11, acidification reaction pond 12, settling tank 13, disk filter 14 and inspissator 15.Air swept mill 11 for grinding titanium mineral It is milled broken, then after the drying titanium mineral after grinding mix with sour mine, reaction generation peptide liquid, peptide liquid in acidification reaction pond 12 Main component be titanium sulfate, titanyl sulfate and ferrous sulfate, in peptide liquid the complete impurity of unreacted in settling tank 13 by Gravity and settle, the supernatant liquor in settling tank 13 obtains clear peptide liquid after heat filtering again.It is soluble in peptide liquid Iron ion can not be removed by heat filtering, after ferrous sulfate is precipitated in peptide liquid decrease temperature and pressure, then pass through disk filter 14 Ferrous sulfate is separated from peptide liquid.Filtered peptide liquid is concentrated into the concentration needed in subsequent handling in inspissator 15.

As shown in Figure 1, calcining pretreating device 2 includes sequentially connected reactor 21, Primary diaphragm filter press 22, bleaching Machine 23, secondary diaphragm filter press 24, salt treatment furnace 25 and filter cake molding machine 26, the peptide liquid after concentration carry out instead in reactor 21 It answers, soluble titanium sulfate and titanyl sulfate are converted into hydrated titanium dioxide precipitating not soluble in water during the reaction, i.e., partially Metatitanic acid.Through Primary diaphragm filter press 22, once washing removes ferrous ion impurity to metatitanic acid again, then will be in reaction through bleaching machine 23 The a small amount of ferric ion generated is reduced to ferrous ion, then washes away through 24 secondary water of secondary diaphragm filter press except ferrous ion Impurity, then through salt treatment furnace 25 physical and chemical properties of metatitanic acid are improved.Metatitanic acid after improvement is passed through into filter 26 filters pressing of cake molding machine can save natural gas and at the filter cake for reaching the requirement of regulation technique convenient for feeding to rotary kiln 31.Instead Answering device 21 is the main source that waste liquid generates in titanium dioxide manufacturing process.

As shown in Figure 1, calcining dust-extraction unit 3 includes sequentially connected rotary kiln 31, dry collector 32 and conveying equipment 33(is referring to fig. 2).Filter cake undergoes the physical changes such as dehydration, desulfurization, crystal transfer and grain growth in rotary kiln 31, generates two Titan oxide particles.A large amount of exhaust gas can be generated in calcination process, exhaust gas is passed through into dry collector 32, and dry collector 32 is received The dust of collection is passed through into conveying equipment 33.

As shown in Figure 1, calcining after-treatment device 4 is mainly used to carry out at surface the titanium dioxide granule that calcining is completed Reason, enhances the physical and chemical performance of titanium dioxide granule, so that titanium dioxide wants particle to be able to satisfy the various demands in practical application, And the waste liquid generated in titanium dioxide granule production process is handled.Calcining after-treatment device 4 includes waste liquid through useless Liquid concentrator 41, the waste liquid generated in production process reach emission request after the processing of waste liquid concentrator 41.

As shown in figure 3, dry collector 32 includes cabinet 321, air inlet 322, air outlet 323, injection tube 324, filter core 325 and back taper ash bucket 326, filter core 325 by stainless steel fibre felt at.When filter cake is calcined in rotary kiln 31, it can generate Exhaust gas largely containing titanium dioxide dust, rotary kiln 31 calcine the exhaust gas of output generally at 400 DEG C or more, and before containing The sulfuric acid components mixed in process, dry collector 32 select filter core 325 made of stainless steel fibre felt, can be directly to high temperature It is dusted with the exhaust gas of highly corrosive, cooling process will be carried out to exhaust gas in advance by reducing in traditional handicraft, it is possible to reduce The use of cooling equipment, reduces the whole occupied area of equipment and reduces economic cost.326 lower end of ash bucket is connected with horizontally disposed Conveying equipment 33, conveying equipment 33 includes feeding pipe 331 and the spiral feeding shaft 332 that is installed in feeding pipe 331, spiral shell Rotation feeding shaft 332 is connected with driving motor 333.

Force to fall grey structure 5(referring to Fig. 3 as shown in figure 4, being equipped in ash bucket 326), it includes shaft that pressure, which falls grey structure 5, 51, the cross bar 511 being fixedly connected with shaft 51 and the scraper plate 512 positioned at 511 both ends of cross bar, the interior table of scraper plate 512 and ash bucket 326 Face abuts, and shaft 51 is connect by bevel gear set 52 with the output end of driving motor 333.Titanium dioxide dust may be in ash bucket 326 inner surfaces bond and specific yield are caused to decline, and pressure falls grey structure 5 can be by the titanium dioxide powder of 326 inner surface of ash bucket Dirt is scraped and is collected into conveying equipment 33, reduces the waste of material.Pressure falls grey structure 5 and 33 common drive of conveying equipment The setting of motor 333 can also save equipment and be taken up space.Buffering pipe 327 is equipped between 326 lower end of ash bucket and conveying equipment 33, 51 surface of shaft is located at 327 inner part of buffering pipe and is fixedly connected with spice impeller 513.Buffering pipe 327 can be defeated to entering The titanium dioxide dust of material equipment 33 plays the role of temporarily storing, and titanium dioxide dust falls collection in dry collector 32 Be it is interim, be easy to cause in conveying equipment 33 material accumulation excessive and damage driving motor 333, buffering pipe 327 can be with Realize that material at the uniform velocity supplies in conveying equipment 33, to protect driving motor 333.The setting of spice impeller 513 also may make Titanium white powder particles are further stirred, so that titanium white powder particles blanking is more uniform, are not easy to deposit.

As shown in Fig. 2, passing through level-one return air duct between waste liquid concentrator 41 and the air outlet 323 of dry collector 32 411 connections, can generate a large amount of sulfuric acid waste during manufacturing titanium dioxide using sulfuric acid process, by sulfuric acid waste in traditional handicraft It neutralizes and generates laterite, a large amount of laterite presence takes up a large area and reluctant problem, this titanium dioxide calcining dry method, which is gathered dust, is System directly can be concentrated waste liquid high temperature to form sulfuric acid product, reaction material is recycled by the way of waste liquid concentration It utilizes, it is more environmentally-friendly.The exhaust gas temperature of 32 air outlet 323 of dry collector can reach 200 degrees Celsius or more, contained in exhaust gas Heat belongs to low-quality thermal energy, therefore portion is passed through in waste liquid concentrator 41, on the one hand can be by the sulphur in exhaust gas Sour component is dissolved in the yield that waste liquid concentration is improved in waste liquid, on the other hand can preheat to waste liquid concentrator 41, reduces The energy loss that external heating generates in concentration process.Rotary kiln 31 includes kiln hood 311, the air outlet 323 of dry collector 32 It is connect with the kiln hood 311 of rotary kiln 31 by second level return air duct 312, second level return air duct 312 is equipped with volume control damper 313, second level return air duct 312 is equipped with airflow meter 314 at kiln hood 311.The exhaust gas of air outlet 323 can carry out kiln hood 311 Preheating reduces the usage amount of calcinating fuel in rotary kiln 31, while the entrance of exhaust gas also has the function of tonifying Qi, can make more More air participate in calcination process, improve burning quality.The setting of volume control damper 313 is adjustable to enter rotary kiln 31 Exhausted air quantity, staff can according to calcining demand adjust volume control damper so that air compensation rises or falls, thus into one Step improves the burning quality in rotary kiln, and the setting of airflow meter 314 can be convenient operator and be monitored to exhaust gas inlet.

As shown in Fig. 2, being equipped with level-one temperature measurer 3221 at the air inlet 322 of dry collector 32, it is equipped at air outlet 323 Second level temperature measurer 3231, level-one temperature measurer 3221 and second level temperature measurer 3231 are electrically connected with PLC controller 34.Level-one temperature measurer 3221 and second level temperature measurer 3231 can respectively to calcining before and calcined exhaust gas temperature be monitored, if exhaust gas temperature does not reach To defined standard, PLC controller 34 receives signal can control equipment downtime in time, for depositing in operator's discovering device The problem of and carry out repair and maintenance.In addition, sulfuric acid solution is being lower than 230 degrees Celsius due in the method for the production titanium dioxide When can liquefy, therefore to guarantee minimum temperature in dust removal process, i.e., the temperature at air outlet 323 is higher than 230 degrees Celsius, can The degree of corrosion is received to effectively reduce filter core 325 and other 32 components of dry collector, extends dry collector 32 and uses the longevity Life.

As shown in Fig. 2, being equipped with level-one air gauge 3222 at the air inlet 322 of dry collector 32, it is equipped at air outlet 323 Second level air gauge 3232, level-one air gauge 3222 and second level air gauge 3232 are electrically connected with PLC controller 34, PLC controller 34 are electrically connected with injection tube 324.It, can be through filtration core when gas reaches air outlet 323 from the air inlet 322 of dry collector 32 325, the Dust Capacity of its surface aggregation in dust removal process of filter core 325 can be continuously increased, so that when gas is through filtration core 325 Resistance increase, cause the air pressure at air outlet 323 to reduce.Gas between level-one air gauge 3222 and second level air gauge 3232 When pressure difference reaches defined critical value, then show that the dust saved bit by bit on filter core 325 is excessive and has influenced gas in dry type Proper flow in deduster 32.PLC controller 34 receives signal and controls the starting blowing of injection tube 324 at this time, by filter core Dust on 325 is blown off into ash bucket 326.

Specific implementation process: the heat that exhaust gas generates in 32 dust removal process of dry collector can be to waste liquid concentrator 41 It is preheated with rotary kiln 31, reduces the use of the energy for heat production.The titanium dioxide granule that dry collector 32 is collected is received It can be directly entered processing in subsequent technique after collection and generate titanium dioxide product, reduce wastage of material and improve yield.

This specific embodiment is only the explanation to the utility model, is not limitations of the present invention, ability Field technique personnel can according to need the modification that not creative contribution is made to the present embodiment after reading this specification, but As long as all by the protection of Patent Law in the scope of the claims of the utility model.

Claims (8)

1. a kind of titanium dioxide calcines dry method dust collecting system, including sequentially connected pretreatment unit (1), calcining pretreating device (2), dust-extraction unit (3) and calcining after-treatment device (4) are calcined, calcining dust-extraction unit (3) includes rotary kiln (31), and feature exists In: the rotary kiln (31) is connected with dry collector (32), and the dry collector (32) includes cabinet (321), air inlet (322), the ash bucket (326) of air outlet (323), injection tube (324), filter core (325) and back taper, the filter core (325) is not by Steel fibre felt of becoming rusty is at ash bucket (326) lower end is connected with horizontally disposed conveying equipment (33), the conveying equipment (33) Including feeding pipe (331) and the spiral feeding shaft (332) being installed in feeding pipe (331), the spiral feeding shaft (332) It is connected with driving motor (333).

2. a kind of titanium dioxide according to claim 1 calcines dry method dust collecting system, it is characterised in that: the ash bucket (326) Interior be equipped with forces to fall grey structure (5), and the pressure falls the cross that grey structure (5) includes shaft (51), is fixedly connected with shaft (51) Bar (511) and the scraper plate (512) for being located at cross bar (511) both ends, the scraper plate (512) abut with the inner surface of ash bucket (326), institute Shaft (51) are stated to connect by bevel gear set (52) with the output end of driving motor (333).

3. a kind of titanium dioxide according to claim 2 calcines dry method dust collecting system, it is characterised in that: the ash bucket (326) Buffering pipe (327) are equipped between lower end and conveying equipment (33), it is internal that shaft (51) surface is located at buffering pipe (327) Divide and is fixedly connected with spice impeller (513).

4. a kind of titanium dioxide calcining dry method dust collecting system stated according to claim 1, it is characterised in that: the titanium dioxide calcining is dry Method dust collecting system includes waste liquid concentrator (41), the air outlet of the waste liquid concentrator (41) and dry collector (32) (323) it is connected between by level-one return air duct (411).

5. a kind of titanium dioxide according to claim 4 calcines dry method dust collecting system, it is characterised in that: the rotary kiln (31) Including kiln hood (311), the air outlet (323) of the dry collector (32) and the kiln hood (311) of rotary kiln (31) pass through second level Return air duct (312) connection.

6. a kind of titanium dioxide according to claim 5 calcines dry method dust collecting system, it is characterised in that: the second level backwind tube Road (312) is equipped with volume control damper (313), and the second level return air duct (312) is equipped with airflow meter at kiln hood (311) (314)。

7. a kind of titanium dioxide according to claim 1 calcines dry method dust collecting system, it is characterised in that: the dry collector (32) level-one temperature measurer (3221) are equipped at air inlet (322), second level temperature measurer is equipped at the air outlet (323) (3231), the level-one temperature measurer (3221) and second level temperature measurer (3231) are electrically connected with PLC controller (34).

8. a kind of titanium dioxide according to claim 1 calcines dry method dust collecting system, it is characterised in that: the dry collector (32) level-one air gauge (3222) are equipped at air inlet (322), second level air gauge is equipped at the air outlet (323) (3232), the level-one air gauge (3222) and second level air gauge (3232) are electrically connected with PLC controller (34), the PLC Controller (34) is electrically connected with injection tube (324).