CN104084035A - Dry-process denitration process of rotary cement kiln and equipment - Google Patents
Dry-process denitration process of rotary cement kiln and equipment Download PDFInfo
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- CN104084035A CN104084035A CN201410366962.9A CN201410366962A CN104084035A CN 104084035 A CN104084035 A CN 104084035A CN 201410366962 A CN201410366962 A CN 201410366962A CN 104084035 A CN104084035 A CN 104084035A
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Abstract
The invention relates to a dry-process denitration process of a rotary cement kiln and equipment, belonging to the technical field of cement denitration. The dry-process denitration process is characterized by comprising the steps of forming a hole in one section of the kiln from parallel flues at the tail of a rotary cement kiln (20) to the lower part of a fifth-stage preheater (18) of fifth stages of cyclone preheaters and pneumatically conveying and urea particles into the hole, wherein the temperature of the hole position of the fifth-stage preheater is 850-950 DEG C, and the mol ratio of the adding amount of urea to NOx in flue gas of the fifth-stage preheater is (1-2.5) to 3. The equipment of the denitration process is characterized in that a blower pipe (10) is inserted into the hole formed in the lower part of the fifth-stage preheater (18), and is connected with a urea blowing device. The equipment is low in reconstruction investment, and completes denitration once; the dry-process denitration process is dry-process denitration, water content in the kiln is not increased, the atmosphere in the kiln is not affected, and heat loss is avoided. Reaction is thorough without causing ammonia escape.
Description
Technical field
Cement rotary kiln dry method denitrating technique and equipment thereof, belong to cement denitration technology field.
Background technology
The production process of cement kiln is supervened a large amount of oxynitrides, and this class nitrogen oxide is one of main atmosphere pollution.Traditional gas denitrifying technology is SCR technology and SNCR technology, and SCR technology denitration efficiency is high, but system complex, catalyst life is short, and operating cost is high.And SNCR technical operation cost is few, system is simple, but its denitration efficiency is low, can not reach the standard of present discharge.
Chinese patent CN 102512925 B < < cement kiln flue-gas denitration process and denitrification apparatus > > disclose after a kind of wet denitration the cement kiln denitration technology in conjunction with the denitration of SCR technology secondary again./ 2nd places that this technology is decomposed the tail flue gas pipeline of kiln at cement spray into reducing agent, the preferred 10m/s ~ 20m/s of the speed that sprays into of reducing agent.The reducing agent amount of spraying into is the NH in reducing agent
3with the mol ratio of NOx in flue gas be 1.1: 1 ~ 2.5: 1.Then flue gas enters SCR reactor again and utilizes catalyst to carry out secondary denitration.Wherein reducing agent used is one or more in liquefied ammonia, ammoniacal liquor or urea.This denitrating technique is applicable to cement kiln denitrating flue gas, and denitration efficiency is high.But larger to cement kiln change, technique is obviously imitated the denitration of coal-burning boiler, needs secondary denitration just can get a desired effect.And the mode that sprays into of its reducing agent is not broken away from the restriction of wet denitration, reducing agent need to be prepared as to solution or liquid could realization by flow velocity sprays into.Inflammable, explosive, perishable, difficult transportation that the reductant solution that this wet denitration is used exists, stores difficult shortcoming, and operating cost is high.Moreover spray denitrfying agent and contain large quantity of moisture, affect cement burning quality and kiln atmosphere, main is to cause cement kiln heat to run off, increase coal consumption.During operation, operation requirements is strict, and its excessive ammonia adding easily causes the escaping of ammonia, forms secondary pollution; Otherwise need to increase the exhaust treatment system of ammonia.Because its equipment energy characteristic also needs to be first prepared into urea liquid, the problem that the large quantity of moisture in urea liquid causes cement kiln heat to run off when using the carbamide reducing agent of unique convenient transportation.Urea to thermally labile, is heated to 80 ℃ and just can be decomposed into ammonia and carbon dioxide in the aqueous solution.Actual effect and ammoniacal liquor almost do not have difference.
Summary of the invention
The technical problem to be solved in the present invention is: overcome the deficiencies in the prior art, a kind of technological process is short, operating cost supports, the interior heat of cement kiln runs off little cement rotary kiln dry method denitrating technique and equipment thereof are provided.
The technical solution adopted for the present invention to solve the technical problems is: this cement rotary kiln dry method denitrating technique, it is characterized in that, processing step is: at the parallel flue of cement kiln rotary kiln to one section of kiln upper shed of the level V preheater bottom of five-stage cyclone preheater wind, send and be blown into urea granules; Described aperture position temperature is at 850 ℃ ~ 950 ℃, and urea thermal decomposition under this high temperature is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xgeneration non-catalytic reduction reacts, and reaches the effect of denitration; NO in the flue gas of the addition of urea and level V preheater wherein
xmol ratio be 1 ~ 2.5:3.
The particle diameter of described urea granules is 0.5mm ~ 2mm.
It is raw material that dry method denitration technology be take the urea of high reaction activity, and urea is as a kind of solid ammonia base reductant (NR
3) at 850 ℃ ~ 950 ℃, be blown in temperature range rapid and NO
xthere is reduction reaction and reach denitration object.The plurality of advantages such as it has transportation, stores conveniently, and power consumption is few.Utilizing urea to carry out dry method denitration technology is to utilize amino reductive (NR
3) in medium reaction temperature, without catalyst condition under with NO
xreact and reach denitration object.Dry method denitration technology is not introduced moisture in denitrification process, can not increase coal consumption because of reducing temperature, can not destroy kiln atmosphere yet.
Urea under drying condition at high temperature decomposes and produces ammonia and cyanic acid, and the nitrogen element in reduction-state exists with ammonia and two kinds of forms of cyanic acid, can not produce water and carbon dioxide and affect kiln atmosphere and cement burning quality in pyrolysis process.Ammonia and cyanic acid are at high temperature to NO
xcarry out denitration reaction, realize efficiently removing of low mol ratio.Cyanic acid is at high temperature as NO
xa kind of rapidly-decomposing, can there is 8HNCO+6NO
2=7N
2+ 8CO
2+ 4H
2the reaction of O.Due to ammonia and cyanic acid and NO
xdemand temperature during reaction is different, so the temperature range that in the present invention, the nitrogen element of reduction-state adapts to is wider, and can be to NO in five-stage cyclone preheater
xcarry out more thorough denitration.NO
xonce remove thoroughly, without secondary denitration, simplification of flowsheet, simplifies cement equipment and changes.Eliminated wet denitration because of denitration efficiency low, excess ammonia drop into can not with NO
xfully reflection causes the problem of the escaping of ammonia, or needs follow-up problem of carrying out ammonia vent gas treatment.
Simultaneously because urea of the present invention be blown into point selection at the parallel flue of rotary kiln to one section of kiln of the level V preheater bottom of five-stage cyclone preheater, flue dust in this section of kiln flows in whirlwind formation point the thermal decomposition product of urea is circulated in five-stage cyclone preheater, increased time of contact, sufficient and NO
xreact.In other positions, add urea because be not to form point in whirlwind, the nitrogen element of reduction-state all can not or can not all participate in circulating in five-stage cyclone preheater, and denitration efficiency reduces.
A kind of equipment of above-mentioned cement rotary kiln dry method denitrating technique, comprise five-stage cyclone preheater, the level V preheater of five-stage cyclone preheater is by parallel flue conjunctive decomposition kiln, level V preheater bottom connects rotary kiln, it is characterized in that: at the parallel flue of cement kiln rotary kiln, to one section of kiln upper shed of the level V preheater bottom of five-stage cyclone preheater, insert blower pipe, blower pipe connects urea blowing device.
Described urea blowing device comprises that urea lifting subassembly, urea store weigh assembly, airflow blow assembly, urea lifting subassembly is the bucket elevator that bottom is provided with hopper, urea stores the assembly of weighing and comprises feed bin and conveying worm, bucket elevator top is connected to feed bin top by feed-line, on feed bin, run through and be provided with loosening device, under bin bottom opening, connect conveying worm, the discharging opening of conveying worm connects airflow blow assembly and by blower pipe, urea is blowed to level V preheater.Mechanical feed and strength feeding associated form for this equipment Bian, the raw material Bian that puts in storage carries with elevator, enters raw material cabin, and denitrfying agent enters kiln Bian to be carried by strength, and Bian air compressor is wind-power, utilizes blast that denitrfying agent is sent in air channel.
Described loosening device comprises variable frequency reducer motor, agitator arm, agitating vane, and agitator arm runs through and protrudes from feed bin, and agitator arm top is connected with variable frequency reducer motor, and agitator arm bottom is connected to feed bin under shed, and agitating vane is spirally wound on agitator arm lower end.Can be by regulating agitating vane rotating speed tentatively to regulate the addition of urea.
Described conveying worm connects variable-frequency motor.Can be by regulating variable-frequency motor rotating speed to change in real time rotational speed regulation urea conveying capacity.
Described airflow blow assembly comprises air compressor and venturi-type eductors, the gas outlet of air compressor connects the air inlet of venturi-type eductors by compressor reducer pipeline, the charging aperture of venturi-type eductors connects the discharging opening of conveying worm, and the outlet that blows of venturi-type eductors connects blower pipe.
Described air compressor air inlet pipeline is connected with source of the gas tank.
Described feed bin side is provided with observation window.Can observe at any time the surplus of urea in feed bin.
In described level V preheater, be provided with NO
xcontent real-time detection apparatus, the in real time corresponding urea amount of being blown into of adjusting.In dry method flue gas denitration device design, adopt the mode regulating in real time, the nitrogen content of exhaust gas volumn, air quantity and coal dust by kiln, by the method for table ratio, adjusts the amount of being blown into of urea at any time, reaches required denitration treatment effect.
This device can Bian plc automatic control system, connects environmental protection online detection instrument port, can set NO
xcontrolled concentration, autofeed, is controlled by Central Control Room.
Because dry method flue gas denitration device adopts gas gas, mix, need only 850 ℃ of flue-gas temperature >, can reach the treatment effect of expection.Under the different load condition of cement kiln, the adaptability that gas gas mixes, stability, denitration efficiency are better in the interval internal ratio gas-liquid mixed of effective temperature, less on inner operating impact.
Dry method flue gas denitrfying agent (urea) is all gasifications when 850 ℃ of flue-gas temperature >, with the NO in flue gas
xreduction reaction occurs, and product is nitrogen, carbon dioxide and water, can not cause damage to kiln body.
Because dry method flue gas denitration raw material (urea) is packed, so use manual method that urea is dropped in hopper, by bucket elevator, be transported in feed bin; In feed bin, measure also blanking until wind is delivered in flue, whole process is implemented quantitatively control, regulate feeding amount, and environmental protection on-line detector shows whether denitration reaches discharging standards according to smoke dust discharge concentration and control concentration of emission.
Urea is the temperature that is blown into position as the topmost process choice of denitrfying agent.The optimum temperature point of namely selecting cement kiln flue dust to flow to because urea can decompose by heat of gasification 200 ℃ ~ 250 ℃ (I look into be 160 ℃) times, reaches reduction optimum efficiency in the time of 850 ℃ ~ 950 ℃, at this temperature, and catabolite and NO
xproduce chemical reaction, add the special cyclone structure of cement kiln preheater, the nitrogen of reduction-state and NO in catabolite
xin preheater, circulate, after five-stage cyclone preheater, will reach the denitration effect of expection successively, can not produce and escape and secondary pollution.
The shower nozzle that blower pipe inserts level V preheater is heat resisting pipe.
Cement plant need not increase and reforming technology, equipment, only need increase a set of urea blowing device kiln tail preheater is other.
Need not arrange professional production post, because this raw materials technology puts in storage, to require be Manual material feeding, can arrange disposable the feeding intake of workman put in storage according to the denitrfying agent use amount of every day, and device arrangement is patrolled and examined work regular visit.
Feed bin Bian electronics weighing; Frequency conversion spiral blanking for bin blanking Bian, controls and determines blanking-quantity according to computer, solves easily stifled problem of feed opening simultaneously; Under storehouse, carry Bian electronic scale, according to NOx concentration, automatically adjust denitrfying agent consumption at any time.
Compared with prior art, the beneficial effect that cement rotary kiln dry method denitrating technique of the present invention and equipment thereof have is: the technology of the present invention Bian is granular urea with denitration raw material, the factor of nontoxic, tasteless, the safety in production that has no effect, and transportation stores convenient.
The technology of the present invention unit change investment when practical application is little, and a denitration completes, and without increasing secondary denitration device, technological process is short.Without increasing urea melting equipment, equipment operating cost is low.This technology is dry method denitration, can not affect kiln atmosphere to increasing large quantity of moisture in kiln, can not cause heat to run off, and in cement kiln, heat runs off little.
The present invention reacts thoroughly can not cause the escaping of ammonia.Because Bian urea is denitration raw material, and mode of movement is machinery and strength hybrid mode, and feed bin, pipeline, auxiliary equipment all needn't use anti-corrosion material, have saved device fabrication cost and maintenance cost.
Accompanying drawing explanation
Fig. 1 is a kind of urea blowing device structural representation of cement rotary kiln dry method denitrating technique of the present invention.
Fig. 2 is that the urea of cement rotary kiln dry method denitrating technique of the present invention is blown into a mouthful position view.
Wherein: 1, hopper 2, bucket elevator 3, loosening device 4, feed bin 5, conveying worm 6, venturi-type eductors 7, air compressor 8, source of the gas tank 9, compressor reducer pipeline 10, blower pipe 11, variable frequency reducer motor 12, agitator arm 13, agitating vane 14, first order preheater 15, second level preheater 16, third level preheater 17, fourth stage preheater 18, level V preheater 19, decomposition kiln 20, rotary kiln.
The specific embodiment
Fig. 1 ~ 2nd, most preferred embodiment of the present invention, below in conjunction with accompanying drawing 1 ~ 2, the present invention will be further described.
With reference to accompanying drawing 1,2: the equipment of a kind of cement rotary kiln dry method denitrating technique of the present invention, comprise five-stage cyclone preheater, the level V preheater 18 of five-stage cyclone preheater is by flue conjunctive decomposition kiln 19, level V preheater 18 bottoms connect rotary kiln 20 by parallel flue, in level V preheater 18, are provided with NO
xcontent real-time detection apparatus, the in real time corresponding urea amount of being blown into of adjusting.In the parallel flue of rotary kiln 20 kiln tail to one section of kiln upper shed of level V preheater 18 bottoms, insert blower pipe 10, blower pipe 10 connects urea blowing device, urea is blown into the rear thermal decomposition of level V preheater 18, and thermal decomposition product is with flue gas successively process, fourth stage preheater 17, third level preheater 16, second level preheater 15,14 circulations of first order preheater and NO
xreaction; Urea blowing device comprises that bottom is provided with bucket elevator 2, feed bin 4, conveying worm 5 and the airflow blow assembly of hopper 1, bucket elevator 2 tops are connected to feed bin 4 tops by feed-line, on feed bin 4, run through loosening device 3 is set, loosening device 3 comprises variable frequency reducer motor 11, agitator arm 12, agitating vane 13, agitator arm 12 runs through and protrudes from feed bin 4, agitator arm 12 tops are connected with variable frequency reducer motor 11, agitator arm 12 bottoms are connected to feed bin 4 under sheds, and agitating vane 13 is spirally wound on agitator arm 12 lower ends; By regulating variable frequency reducer motor 11 rotating speeds can tentatively regulate urea addition; Under feed bin 4 bottom openings, connect conveying worm 5, conveying worm 5 drives by variable-frequency motor, can change in real time rotational speed regulation urea conveying capacity.The discharging opening of conveying worm 5 connects airflow blow assembly and by blower pipe 10, urea is blowed to level V preheater 18.Airflow blow assembly comprises air compressor 7 and venturi-type eductors 6, and air compressor 7 air inlet pipelines are connected with source of the gas tank 8.The gas outlet of air compressor 7 connects the air inlet of venturi-type eductors 6 by compressor reducer pipeline 9, the charging aperture of venturi-type eductors 6 connects the discharging opening of conveying worm 5, and the outlet that blows of venturi-type eductors 6 connects blower pipe 10.Wherein, hopper 1 is sent denitrfying agent into bucket elevator 2; Bucket elevator 2 rises to feed bin 4 by denitrfying agent; Loosening device 3 is evenly sent denitrfying agent into conveying worm 5 and is utilized variable frequency reducer motor 11 to realize elementary function of measuring, and loosening device 3 bottoms have agitating device to increase denitrfying agent mobility; Feed bin 4 is also provided with function of weighing mainly as denitrfying agent container, and conveying worm 5 is weighed and denitrfying agent is evenly sent into venturi-type eductors 6; Venturi-type eductors 6 utilizes Venturi effect after the supercharging of denitrfying agent urea, to spray into level V preheater 18.
Embodiment 1
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 1.5mm blows to the bottom of the level V preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2:3 is blown into urea.The aperture position urea of Real-Time Monitoring level V preheater is blown into front temperature at 900 ℃, and urea is blown into rear temperature at 899 ℃, before and after urea is blown into, does not occur the obvious temperature difference; Under the high temperature of urea in level V preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 40mg/m
3, the concentration of ammonia is 1.1ppm.
Embodiment 2
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 1.0mm ~ 2mm blows to the bottom of the level V preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 1.8:3 is blown into urea.The aperture position urea of Real-Time Monitoring level V preheater is blown into front temperature at 890 ℃, and urea is blown into rear temperature at 889 ℃, before and after urea is blown into, does not occur the obvious temperature difference; Under the high temperature of urea in level V preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 42mg/m
3, the concentration of ammonia is 1.2ppm.
Embodiment 3
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 2mm blows to the bottom of the level V preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.5:3 is blown into urea.The aperture position urea of Real-Time Monitoring level V preheater is blown into front temperature at 850 ℃, and urea is blown into rear temperature at 850 ℃, before and after urea is blown into, does not occur the obvious temperature difference; Under the high temperature of urea in level V preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 39mg/m
3, the concentration of ammonia is 1.0ppm.
Embodiment 4
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 2mm blows to the mouth that is blown on the parallel flue of cement kiln rotary kiln through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 1:3 is blown into urea.The aperture position urea of Real-Time Monitoring level V preheater is blown into front temperature at 950 ℃, and urea is blown into rear temperature at 949 ℃, before and after urea is blown into, does not occur the obvious temperature difference; Under the high temperature of urea in level V preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 47mg/m
3, the concentration of ammonia is 0.8ppm.
Comparative example 1 position
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 1.5mm blows to level V preheater and decomposes the flue centre position between kiln through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.0:3 is blown into urea.The aperture position urea of Real-Time Monitoring level V preheater is blown into front temperature at 900 ℃, and urea is blown into rear temperature at 900 ℃, does not occur the obvious temperature difference; Urea is decomposed into ammonia and cyanic acid in parallel flue, and the thermal decomposition product of part urea flows with flue gas recirculation in five-stage cyclone preheater, with NO in flue gas
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 91mg/m
3, the concentration of ammonia is 8ppm.
Comparative example 2 positions
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 1.5mm blows to the bottom of the fourth stage preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.0:3 is blown into urea.The aperture position urea of Real-Time Monitoring fourth stage preheater is blown into front temperature at 860 ℃, and urea is blown into rear temperature at 860 ℃, does not occur the obvious temperature difference; Under the high temperature of urea in fourth stage preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, with NO in flue gas
xthe reaction of generation non-catalytic reduction, the NO of first order preheater outlet
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 163mg/m
3, the concentration of ammonia is 17ppm.
Comparative example 3 temperature
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 1.5mm blows to the bottom of the level V preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.0:3 is blown into urea.The aperture position urea of controlling level V preheater is blown into front temperature at 750 ℃, and urea is blown into rear temperature at 749 ℃, does not occur the obvious temperature difference; Owing to there is no very first time thermal decomposition under the high temperature of urea in level V preheater, be ammonia and cyanic acid, the thermal decomposition product of part urea forms point at non-whirlwind and decomposes, and cannot all with flue gas recirculation, flow, with NO in flue gas
xthe reaction of generation non-catalytic reduction, the NO in first order preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 96mg/m
3, the concentration of ammonia is 9ppm.
Comparative example 4 temperature
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The particle diameter of particle is that the urea of 0.5mm ~ 1.5mm blows to the bottom of the level V preheater of cement kiln five-stage cyclone preheater and is blown into mouth through urea blowing device; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.0:3 is blown into urea.The aperture position urea of controlling level V preheater is blown into front temperature at 1100 ℃, and urea is blown into rear temperature at 1100 ℃, does not occur the obvious temperature difference; Under the high temperature of urea in level V preheater, thermal decomposition is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xthe reaction of generation non-catalytic reduction, the NO in first order preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 47mg/m
3, the concentration of ammonia is 1.2ppm.The further lifting of temperature does not obtain better denitration effect, increases in vain energy consumption, and even, because of excess Temperature, air-flow comparatively fast could not reach best denitration effect.
Comparative example 5 solution
NO in level V preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 800mg/m
3.The concentration bottom that to be 10% urea liquid spray into the level V preheater of cement kiln five-stage cyclone preheater with the speed of 15m/s is blown into mouth; With NO in the addition of urea and the flue gas of level V preheater
xmol ratio be that 2.0:3 sprays into urea.The aperture position urea of Real-Time Monitoring level V preheater sprays into front temperature at 900 ℃, and urea sprays into rear temperature at 800 ℃, produces the larger temperature difference, and produce a large amount of steam before and after urea sprays into; Increasing Coal-fired capacity makes the aperture position temperature of level V preheater return to 900 ℃.Under the high temperature of urea in level V preheater, reaction generates ammonia and carbon dioxide, NO in the ammonia of single reducing component and flue gas with steam
xthe reaction of generation non-catalytic reduction, the NO in first order preheater
xcontent real-time detection apparatus detects NO in flue gas
xconcentration is 189mg/m
3, the concentration of ammonia is 41ppm.Spray denitrfying agent and contain large quantity of moisture, affect cement burning quality and kiln atmosphere, main is to cause cement kiln heat to run off, and increases coal consumption.The adaptive temperature narrow range of the best reducing activity of the ammonia of single reducing component, cannot be in cyclic process fully and NO
xreaction.
The above, be only preferred embodiment of the present invention, is not the present invention to be done to the restriction of other form, and any those skilled in the art may utilize the technology contents of above-mentioned announcement to be changed or be modified as the equivalent embodiment of equivalent variations.But every technical solution of the present invention content that do not depart from, any simple modification, equivalent variations and the remodeling above embodiment done according to technical spirit of the present invention, still belong to the protection domain of technical solution of the present invention.
Claims (10)
1. a cement rotary kiln dry method denitrating technique, it is characterized in that, processing step is: at the parallel flue of cement kiln rotary kiln (20) kiln tail to one section of kiln upper shed of level V preheater (18) bottom of five-stage cyclone preheater wind, send and be blown into urea granules; Described aperture position temperature is at 850 ℃ ~ 950 ℃, and urea thermal decomposition under this high temperature is ammonia and cyanic acid, and the thermal decomposition product of urea flows with flue gas recirculation in five-stage cyclone preheater, in the process of passing through successively five-stage cyclone preheater with flue gas in NO
xgeneration non-catalytic reduction reacts, and reaches the effect of denitration; NO in the flue gas of the addition of urea and level V preheater (18) wherein
xmol ratio be 1 ~ 2.5:3.
2. cement rotary kiln dry method denitrating technique according to claim 1, is characterized in that: the particle diameter of described urea granules is 0.5mm ~ 2mm.
3. the equipment of cement rotary kiln dry method denitrating technique described in a claim 1, comprise five-stage cyclone preheater, the level V preheater (18) of five-stage cyclone preheater is by parallel flue conjunctive decomposition kiln (19), level V preheater (18) bottom connects rotary kiln (20), it is characterized in that: at the parallel flue of cement kiln rotary kiln (20) kiln tail, to one section of kiln upper shed of level V preheater (18) bottom of five-stage cyclone preheater, insert blower pipe (10), blower pipe (10) connects urea blowing device.
4. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 3, it is characterized in that: described urea blowing device comprises urea lifting subassembly, urea stores the assembly of weighing, airflow blow assembly, urea lifting subassembly is the bucket elevator (2) that bottom is provided with hopper (1), urea stores the assembly of weighing and comprises feed bin (4) and conveying worm (5), bucket elevator (2) top is connected to feed bin (4) top by feed-line, on feed bin (4), run through and be provided with loosening device (3), under feed bin (4) bottom opening, connect conveying worm (5), the discharging opening of conveying worm (5) connects airflow blow assembly and by blower pipe (10), urea is blowed to level V preheater (18).
5. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 4, it is characterized in that: described loosening device (3) comprises variable frequency reducer motor (11), agitator arm (12), agitating vane (13), agitator arm (12) runs through and protrudes from feed bin (4), agitator arm (12) top is connected with variable frequency reducer motor (11), agitator arm (12) bottom is connected to feed bin (4) under shed, and agitating vane (13) is spirally wound on agitator arm (12) lower end.
6. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 4, is characterized in that: described conveying worm (5) connects variable-frequency motor.
7. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 4, it is characterized in that: described airflow blow assembly comprises air compressor (7) and venturi-type eductors (6), the gas outlet of air compressor (7) connects the air inlet of venturi-type eductors (6) by compressor reducer pipeline (9), the charging aperture of venturi-type eductors (6) connects the discharging opening of conveying worm (5), and the outlet that blows of venturi-type eductors (6) connects blower pipe (10).
8. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 7, is characterized in that: described air compressor (7) air inlet pipeline is connected with source of the gas tank.
9. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 4, is characterized in that: described feed bin (4) side is provided with observation window.
10. the equipment of a kind of cement rotary kiln dry method denitrating technique according to claim 3, is characterized in that: in described level V preheater (18), be provided with NO
xcontent real-time detection apparatus, the in real time corresponding urea amount of being blown into of adjusting.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111514739A (en) * | 2019-02-02 | 2020-08-11 | 广东万引科技发展有限公司 | Novel composite biomass denitration powder for dry-process cement kiln, use method of composite biomass denitration powder and denitration system |
| CN112608049A (en) * | 2020-12-16 | 2021-04-06 | 天津水泥工业设计研究院有限公司 | Cyclic preheating low-energy-consumption carbon-enriched cement production system and method |
| CN113069909A (en) * | 2021-03-03 | 2021-07-06 | 内乡县泰隆建材有限公司 | Cement kiln denitrification facility |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1993003998A1 (en) * | 1991-08-26 | 1993-03-04 | Cummins Power Generation, Inc. | PROCESS AND APPARATUS FOR REMOVING NOx FROM EXHAUST GASES USING CYANURIC ACID__________________________________________________ |
| CN102512925A (en) * | 2011-12-07 | 2012-06-27 | 浙江天蓝环保技术股份有限公司 | Denitration process and denitration apparatus for cement kiln flue gas |
| CN103611411A (en) * | 2013-12-04 | 2014-03-05 | 无锡雪浪环境科技股份有限公司 | Dry denitration processing device in furnace |
| CN203971747U (en) * | 2014-07-30 | 2014-12-03 | 淄博联创环保科技有限公司 | Cement rotary kiln dry method denitration device |
-
2014
- 2014-07-30 CN CN201410366962.9A patent/CN104084035B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1993003998A1 (en) * | 1991-08-26 | 1993-03-04 | Cummins Power Generation, Inc. | PROCESS AND APPARATUS FOR REMOVING NOx FROM EXHAUST GASES USING CYANURIC ACID__________________________________________________ |
| CN102512925A (en) * | 2011-12-07 | 2012-06-27 | 浙江天蓝环保技术股份有限公司 | Denitration process and denitration apparatus for cement kiln flue gas |
| CN103611411A (en) * | 2013-12-04 | 2014-03-05 | 无锡雪浪环境科技股份有限公司 | Dry denitration processing device in furnace |
| CN203971747U (en) * | 2014-07-30 | 2014-12-03 | 淄博联创环保科技有限公司 | Cement rotary kiln dry method denitration device |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111514739A (en) * | 2019-02-02 | 2020-08-11 | 广东万引科技发展有限公司 | Novel composite biomass denitration powder for dry-process cement kiln, use method of composite biomass denitration powder and denitration system |
| CN112608049A (en) * | 2020-12-16 | 2021-04-06 | 天津水泥工业设计研究院有限公司 | Cyclic preheating low-energy-consumption carbon-enriched cement production system and method |
| CN113069909A (en) * | 2021-03-03 | 2021-07-06 | 内乡县泰隆建材有限公司 | Cement kiln denitrification facility |
| CN113069909B (en) * | 2021-03-03 | 2023-03-21 | 内乡县泰隆建材有限公司 | Cement kiln denitrification facility |
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| CN104084035B (en) | 2016-01-13 |
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