CN202169130U

CN202169130U - Tower top dust recovery device of urea prilling tower

Info

Publication number: CN202169130U
Application number: CN2011202634272U
Authority: CN
Inventors: 姚恒龙
Original assignee: ZHENJIANG HENGSHENGDA CHEMICAL INDUSTRY TECHNOLOGY Co Ltd
Current assignee: ZHENJIANG HENGSHENGDA CHEMICAL INDUSTRY TECHNOLOGY Co Ltd
Priority date: 2011-07-22
Filing date: 2011-07-22
Publication date: 2012-03-21
Anticipated expiration: 2021-07-22

Abstract

The utility model discloses a tower top dust recovery device of a urea prilling tower, which comprises a tower body of the prilling tower and a receiving disc arranged in the tower body, wherein a cylindrical dust recovery chamber is mounted at the top of the tower body; the diameter of the dust recovery chamber is larger than the diameter of an air outlet of a tower top; sprinklers are arranged at the upper end and the lower end of the dust recovery chamber; a packing dust collecting device formed by inclined clapboards is mounted between the sprinklers at the two ends of the dust recovery chamber; the bottom end of the receiving disc is connected with a material pipe and a filter; a material outlet of the filter is connected with a circulating pump via a material control valve; then an outlet of the circulating pump is connected with the sprinklers at the upper end and the lower end in the dust recovery chamber via pipelines; a branch pipe leading to an evaporator is connected between the filter and the material control valve; and a water supplementing branch pipe is arranged between the material control valve and the circulating pump. The tower top dust recovery device has the advantages that by adopting a tail gas filtering, washing and absorbing device of the urea prilling tower, the environment is protected, more importantly, the effective value is recovered, the waste of resources is reduced, and the investment in the device can be recovered very quickly.

Description

Carbamide granulation column overhead device for recovering powder

Technical field

This practical a kind of device for recovering powder and method of newly relating to, a kind of specifically carbamide granulation column overhead device for recovering powder and recovery method.

Background technology

In the present most of production of chemical fertilizer enterprise; Usually all be entrained with very important carbamide dust and ammonia in the tail gas of urea prilling tower; Carbamide dust soluble in water, ammonia and condensation product not soluble in water are arranged; Particularly present, most of producers expand the scale of production under the constant situation of original granulation tower.The producer that has is transformed into 200,000 tons of ∕ urea on the basis of 40,000 tons of ∕ urea, the nuisance quality such as dust of granulation tower discharging are along with the expansion of producing constantly increases, and tail gas contains dust concentration generally at 300-700 ㎎ ∕ Nm ³, environmental pollution is serious day by day; Generally speaking, producing 200000 tons of granulation towers per year can pollute the environment in the radius 6Km scope, forms the stronger atmospheric environment of corrosiveness.More existing production of chemical fertilizer enterprises are many employing watering dedustings in the cat head dedusting; But because dusty gas has higher temperature usually; Heat in the process of dedusting in the gas makes water evaporation, can evaporate a large amount of urea liquids simultaneously, causes efficiency of dust collection low; Energy utilization rate is not high, surrounding enviroment is produced pollute.

Practical fresh content

Originally practical new technical problem to be solved is, overcomes the shortcoming of prior art, and a kind of carbamide granulation column overhead device for recovering powder and recovery method are provided, and effectively improves the dust rate of recovery of granulation tower, and can reduce the pollution to environment.

In order to solve above technical problem, this is practical newly to provide a kind of carbamide granulation column overhead device for recovering powder, comprises granulation tower tower body and the receiving plate that is arranged in the tower body; At said tower body top cylindrical dust is installed and reclaims the chamber; Said dust reclaims the chamber diameter greater than said cat head venthole diameter, is provided with at the two ends up and down of said dust recovery chamber and spills the pouring device, and two ends are spilt to drench the filler dust exhaust apparatus of being made up of tilt clapboard is installed between the device; The tilt clapboard of said filler dust exhaust apparatus and the angle of horizontal plane are less than 90 °; The incline direction of said tilt clapboard is consistent, the flanging in the lower end of said tilt clapboard, and said flanging direction is vertical with horizontal plane; Said receiving plate bottom is connected to the material pipe and links to each other with filter, and the discharging opening of said filter connects circulating pump through the material controlling valve, through pipeline spilling of said circulating-pump outlet and the indoor two ends up and down of said dust recovery is drenched device again and links to each other; Be connected to arm and the concentration detection apparatus that leads to evaporimeter between said filter and the material controlling valve, be provided with the moisturizing arm between said material controlling valve and the said circulating pump.

At first, this practical newly reasonably being provided with in the recovered overhead chamber is spilt the pouring device up and down, and the lower end is spilt and drenched the water smoke that device sprays most particle in the dusty gas is absorbed, and gathers into heavy-fluid and drips the receiving plate that falls in the tower, forms " once absorbing "; Remaining fine dusts particle spills under the unrestrained water smoke effect of drenching device in the upper end, on the dust suction filler, fully absorbs once more, and the most dust in the gas are removed, and forms " secondary absorption "; This shows that this practical newly being provided with is cleverly spilt the pouring device up and down, absorb, make full use of the water smoke dust suction and reach the sufficient purpose of absorption thereby particle is formed secondary.

In addition, this practical new science be provided with the filler device of forming by tilt clapboard spilling up and down to drench between the device, the tilt clapboard that is provided with at interval is that air-flow rises passage is provided, and owing to being obliquely installed, more plays the effect of water conservancy diversion; In addition, the polylith tilt clapboard gives also that gas-liquid up and down is liquid-solid to provide sufficient mass-and heat-transfer area, increases time of contact, helps dust and absorbs; The flanging that is positioned at the dividing plate lower end more helps the rising of air-flow on the one hand; Strengthened the water conservancy diversion effect; Guide functions is provided for again on the other hand the drop that descends after the dust suction, model under the drop after helping absorbing, thus play " bidirectional guide " effect; Reduce flow resistance, reduce the load carried of power-equipment.

Moreover; Basis is practical newly to be provided with the arm that leads to vapo(u)rization system through the exit at filter; According to control material control valve, moisturizing manifold valve in the information of the concentration detection apparatus at mouth of pipe place and lead to vapo(u)rization system the arm valve unlatching or close; Can guarantee working well of whole system, and can timely the feed liquid that reclaims be recycled, reduce the secondary pollution that causes because of the evaporation of high concentration feed liquid.

This practical new technical scheme that further limits is: aforesaid carbamide granulation column overhead device for recovering powder; Said tilt clapboard and horizontal plane angle are 30 °～60 °; The distance between plates of said tilt clapboard is 200mm～300 mm; The drop that helps forming can trickle to tower smoothly fast, improves the absorptivity of dust.

Aforesaid carbamide granulation column overhead device for recovering powder, said tilt clapboard is fixedly mounted on said dust through the horizontal bar plate and reclaims on the chamber interior walls, has guaranteed tilt clapboard under the impact of air-flow, and it is mobile not deform, and makes mass-and heat-transfer efficient higher.

Aforesaid carbamide granulation column overhead device for recovering powder, said dust reclaim the chamber to spill the opening direction that drenches device relative at two ends up and down, reclaim the indoor atomized drop that is full of at dust, can combine with carbamide dust fully.

Further, aforesaid carbamide granulation column overhead device for recovering powder, said spilling drenched device and is uniformly distributed with by some spraying nozzles and combines.

The recovery method of aforementioned urea granulation tower cat head device for recovering powder; Comprise the steps: that (1) dusty gas is after the cat head venthole gets into said dust recovery chamber; Reclaiming the droplet that spills the ejection of pouring device in the lower end, chamber with said dust combines; Form drop and drop down onto the receiving plate in the said granulation tower body, the dust that does not combine with droplet is drift upwards; (2) the residue dusty gas reclaims the upper end, chamber with dust and spills and drench the droplet that device sprays and carry out mass-and heat-transfer on the said filler dust exhaust apparatus of being made up of tilt clapboard; The carbamide dust and the gas ammonia that absorb in the dusty gas form in the receiving plate in stream of liquid droplets to the granulation tower body, and on-condensible gas and inert gas reclaim top, chamber steam vent by said dust and discharge; (3) urea liquid in said receiving plate if urea concentration is higher than 18%, is then delivered to vapo(u)rization system by pipeline after pipeline flow to filter and filters, and closes or reduces the material controlling valve, opens the moisturizing arm simultaneously and supplies water to circulating pump; If the solution concentration after filter filters is not higher than 18%, then delivers to cat head and spill and drench device and absorb circulation by circulating pump.

This practical new beneficial effect is: this practical new construction is reasonable, simple to operate; Being employed in granulation tower top setting height(from bottom) is the dust recovery chamber about 3 meters; And the hot air outlet diameter that the design dust reclaims the chamber makes dust go out tower and just slows down greater than former tower hot air outlet diameter, and dust falls naturally; Alleviated the load of dust suction filler, made assimilation effect better; Dust-laden hot gas reclaims the chamber through dust, and the water smoke that spills pouring with top and the bottom on the dust suction filler carries out heat and mass, and carbamide dust and gas ammonia are absorbed fully, reaches the purpose of dedusting; No longer including a lot of atomized steam at the granulation tower top sheds; Even if the steam that distributes also only contains the urea liquid of very small amount; This is practical newly to greatly reduce the pollution to environment to the form recycling of urea with solution, and effective organic efficiency of this nested structure can reach more than 80 ﹪.

Description of drawings

Fig. 1 is this practical new embodiment schematic flow sheet.

Fig. 2 is this practical new tilt clapboard filler dust exhaust apparatus structural representation.

The specific embodiment

Embodiment 1

A kind of carbamide granulation column overhead device for recovering powder that present embodiment provides, structure is as shown in Figure 1, comprises granulation tower tower body 1 and the receiving plate 2 that is arranged in the tower body; At said tower body top cylindrical dust is installed and reclaims chamber 3, form the middle heat air chamber at cat head; Said dust reclaims the chamber diameter greater than said cat head venthole diameter, is provided with at the two ends up and down that said dust reclaims the chamber to be uniformly distributed with to combine to spill by some spraying nozzles to drench device 4, and the shower nozzle direction is oppositely arranged; Spill the filler dust exhaust apparatus 5 that installation is made up of tilt clapboard between the pouring device at two ends; The incline direction of said tilt clapboard is consistent, 6 flangings in the lower end of said tilt clapboard, and said flanging direction is vertical with horizontal plane; Tilt clapboard is fixedly mounted on said dust through horizontal bar plate 13 and reclaims on the inwall of chamber 3; Guaranteed tilt clapboard under the impact of air-flow, it is mobile not deform, and makes mass-and heat-transfer efficient higher; Said receiving plate 2 bottoms are connected to the material pipe and link to each other with filter 7, and the discharging opening of said filter connects circulating pump 9 through material controlling valve 8, through pipeline spilling of said circulating pump 9 outlets and the indoor two ends up and down of said dust recovery are drenched device 4 again and link to each other; Be connected to arm 10 and the concentration detection apparatus that leads to vapo(u)rization system between said filter 7 and the material controlling valve 8, be provided with moisturizing arm 11 between said material controlling valve 8 and the said circulating pump 9.

In the present embodiment,, designed the model of multiple tilt clapboard because the design relation of dust suction filler the success or failure of a whole set of device for recovering powder for this reason, as shown in Figure 2, through contrast and field experiment, take out one group of best model:

Sequence number	α	h	Result of use
				First group	90°	200mm	The mass transfer dust removing effects is very poor, and gas is through smooth
Second group	70°	200mm	The mass transfer dust removing effects is general, and gas is smooth through
				The 3rd group	60°	200mm	The mass transfer better dust removal effect, gas is smooth through very
The 4th group	45°	200mm	The mass transfer dust removing effects is fine, and gas is very smooth through also
				The 5th group	30°	200mm	The mass transfer better dust removal effect, gas is through smooth

Through contrasting the operating position of each group model in the table, selected 45 ° be the use angle of tilt clapboard, next sprays according to every kind of droplet again and the difference of the flowability of dusty gas mass-and heat-transfer confirms that it is 250mm that the distance between plates of tilt clapboard is selected h.

This is practical newly to be workflow: the dusty gas in the urea prilling tower gets into hot gas chamber 12; Oarse-grained carbamide dust drops on receiving plate 2 of bottom, hot gas chamber; All the other dust-laden hot gas continue rising and diffuse into dust recovery chamber 3 (dust recovery cross section, gas outlet, chamber is 2 times of cross section, gas outlet, hot gas chamber approximately); At this moment tail gas flow velocity will subtract doppio lunghezza di tempo, drop on dust under the part dust and reclaim 3 li of chambers, and dusty gas continues to rise again; The filler dust exhaust apparatus 5 that entering is made up of tilt clapboard; Hot gas spills the water that the water that drenches and bottom spills pouring to carry out heat and mass, carbamide dust and gas ammonia and thoroughly absorbs through filler dust exhaust apparatus 5 and top, and having dissolved carbamide dust and the water that has absorbed ammonia, to form the low aqueous solution continued of concentration past dirty, contacts with the dust of the deposition of 3 li of dust recovery chambers and dissolves; At the receiving plate 2 that flows into bottom, hot gas chamber; With the big dust particle contact lysis in receiving plate, just obtain the higher about 18-20% of concentration (weight ratio) urea liquid, flow to Urea Evaporation System and process finished product through the following liquid pipeline filter of flowing through; Pass through the circulating pump 9 under material controlling valve 8 and the pipeline entering granulation tower if solution concentration is low, process pressurization back is spilt the pouring device through the pipeline entering and is spilt pouring up and down, absorbs bottom, dust and ammonia inflow hot gas chamber, bottom again and forms the recovery that circulates; Moisturizing arm 11 can mend quantitative water in a bite of advancing of pump with the urea wastewater that contains certain pressure, to fill up the moisture of sending into vapo(u)rization system and losing, guarantees that systemic circulation can run well.

Except that the foregoing description, originally practical newly can also have other embodiments.All employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop on the protection domain of this practical new demand.

Claims

1. a carbamide granulation column overhead device for recovering powder comprises granulation tower tower body and the receiving plate that is arranged in the tower body; It is characterized in that: cylindrical dust is installed at said tower body top reclaims the chamber; Said dust reclaims the chamber diameter greater than said cat head venthole diameter; Be provided with at the two ends up and down that said dust reclaims the chamber and spill the pouring device; Two ends are spilt to drench the filler dust exhaust apparatus of being made up of tilt clapboard are installed between the device, and the tilt clapboard of said filler dust exhaust apparatus and the angle of horizontal plane are less than 90 °, and the incline direction of said tilt clapboard is consistent; The flanging in the lower end of said tilt clapboard, said flanging direction is vertical with horizontal plane; Said receiving plate bottom is connected to the material pipe and links to each other with filter, and the discharging opening of said filter connects circulating pump through the material controlling valve, through pipeline spilling of said circulating-pump outlet and the indoor two ends up and down of said dust recovery is drenched device again and links to each other; Be connected to arm and the concentration detection apparatus that leads to evaporimeter between said filter and the material controlling valve, be provided with the moisturizing arm between said material controlling valve and the said circulating pump.

2. carbamide granulation column overhead device for recovering powder according to claim 1 is characterized in that: said tilt clapboard and horizontal plane angle are 30 °～60 °, and the distance between plates of said tilt clapboard is 200mm～300 mm.

3. carbamide granulation column overhead device for recovering powder according to claim 2 is characterized in that: said tilt clapboard is fixedly mounted on said dust through the horizontal bar plate and reclaims on the chamber interior walls.

4. carbamide granulation column overhead device for recovering powder according to claim 1 is characterized in that: said dust reclaims the chamber, and to spill the opening direction that drenches device relative at two ends up and down.

5. carbamide granulation column overhead device for recovering powder according to claim 4 is characterized in that: said spilling drenched device and is uniformly distributed with by some spraying nozzles and combines.