CN218945003U - Urea prilling tower structure - Google Patents

Abstract

The utility model provides a urea prilling tower structure, which comprises an outer layer tower body, wherein the top part in the outer layer tower body is connected with a ventilating room, the top end of the ventilating room is provided with a dry dust removing device communicated with the ventilating room, the bottom end of the ventilating room is provided with a prilling room communicated with a urea particle forming collecting area at the bottom in the outer layer tower body, the wall of the ventilating room is provided with a plurality of top ventilation holes communicated with the urea particle forming collecting area, and the bottom of the prilling room is gradually contracted from top to bottom. According to the utility model, the ventilation structure and the inter-granulation structure of the granulation tower are optimized, so that the whole granulation tower is better in stress, and the inter-granulation spray liquid can exchange heat better in the granulation tower, thereby greatly reducing the waste of resources and realizing energy conservation and emission reduction under the condition of reaching the environmental protection standard.

Description

Urea prilling tower structure

Technical Field

The utility model belongs to the technical field of urea prilling towers, and particularly relates to a urea prilling tower structure.

Background

The existing urea and compound fertilizer granulating technology can be divided into two major types, namely a fluidized bed granulating technology and a tower granulating technology. Wherein the fluidized bed granulation technology has the dust concentration of the discharged dust reaching less than or equal to 10mg/Nm ³ But due to complex process flow, high investment and operation cost, common manufacturers rarely use the catalyst; most enterprises often adopt natural ventilation tower granulation technology with simple equipment, small investment and low operation cost.

Statistics indicate that: during 1953-2000, the urea powder and dust and ammonia analog of urea-based compound fertilizer prilling tower were substantially vented to atmosphere during production, with the dust emissions of natural ventilation urea and urea-based compound fertilizer prilling tower being about 150-350mg/Nm ³ The ammonia emission is about 80-150mg/Nm ³ . The produced atmospheric pollutants are ordered according to the urea granulation production technology type, and the atmospheric pollutants produced by the urea granulation tower with the natural ventilation structure are arranged first and the proportion of the produced atmospheric pollutants is very large. Therefore, along with the increase of environmental protection pressure, the upgrading and reconstruction of the environmental protection technology of the urea prilling tower aiming at a natural ventilation structure are gradually increased, and the upgrading and reconstruction of the environmental protection technology mainly comprises two technologies of washing dust removal, dry dust removal and the like. The prilling tower modified by the water washing dust removal technology still has the defects of very heavy tail smoke, serious exceeding of emission, serious apparent pollution and the like. The prilling tower modified by the dry dedusting technology has no visible pollutant, and the dust and ammonia emissions are all higher than the existing national standard and industry standard.

As shown in fig. 3, in the granulation tower adopting the dry dust removing device at present, the dry dust removing device is only added at the top of the granulation tower, the structure of the granulation tower is not correspondingly optimized, and after the dry dust removing device is assembled, the tower body is required to be thickened to meet the stress requirement due to poor stress of the tower body, so that a certain resource waste is caused. In addition, in the existing prilling tower, gaps between granulation room and outer tower wall are small, a large amount of wind directly flows upwards from the granulation room and tower wall, and dead angle is formed in a certain area around the urea liquid spraying device; when no wind passes through the dead angle, the heat transfer and exchange of the liquid drops can not be carried out at the dead angle, so that urea liquid drops can not form urea particles.

Disclosure of Invention

Based on the technical problems in the prior art, the utility model provides the urea prilling tower structure, which optimizes the ventilation structure and the inter-prilling structure, so that the whole stress of the urea prilling tower structure is better, and the inter-prilling spray liquid can exchange heat better in the urea prilling tower, thereby reducing energy consumption and reducing resource waste.

According to the technical scheme of the utility model, the utility model provides a urea prilling tower structure, which comprises an outer layer tower body, wherein the top in the outer layer tower body is connected with a ventilating room, the top end of the ventilating room is provided with a dry dust removing device communicated with the ventilating room, the bottom end of the ventilating room is provided with a prilling room communicated with a urea particle forming collecting area at the bottom in the outer layer tower body, the wall of the ventilating room is provided with a plurality of top vent holes communicated with the urea particle forming collecting area, and the bottom of the prilling room is gradually contracted from top to bottom; the fan at the top is arranged in the granulation room.

Preferably, the top vent hole is arranged on a wall body vertically arranged in the granulation room, the top vent hole is a round hole and/or a kidney-shaped hole, and the top vent hole is a window type vent hole without activity.

Preferably, the bottom of the granulation chamber is in an inverted truncated cone shape, a spraying device is arranged on the lower bottom surface of the inverted truncated cone-shaped bottom of the granulation chamber, a nozzle of the spraying device is arranged on the bottom side of the granulation chamber, and a maintenance space is reserved on the lower bottom surface.

Preferably, a collecting device is further arranged on the outer layer tower body at the bottom side of the urea particle forming collecting area, and a plurality of bottom ventilation holes are further arranged on the outer layer tower body at the upper side of the collecting device.

Preferably, the bottom vent is a circular hole and/or a kidney-shaped hole, and the bottom vent is a vent without movable window.

Preferably, the collecting device comprises a funnel-shaped material carrying disc, a scraping machine is arranged on the top side of the upper opening of the material carrying disc, and a conveying belt is arranged on the bottom side of the lower opening of the material carrying disc.

Preferably, the plurality of top vents or bottom vents are staggered in both the lateral or vertical directions.

Preferably, the dry dust collector comprises a filter bag dust collector at the top end of the plenum, and a suction fan at the top end of the filter bag dust collector in communication with the filter bag dust collector.

Compared with the prior art, the urea prilling tower structure has the following advantages:

1. the utility model cancels the rectangular shutter at the bottom of the outer wall body and the top of the inner wall body (at the ventilating room), changes into a plurality of smaller round or waist-shaped holes, and staggers the ventilating holes in the transverse and vertical directions on the premise of meeting the ventilation quantity, so as to optimize the stress structure of the outer wall and the inner wall of the urea prilling tower, thereby being capable of properly reducing the thickness of the outer wall of the tower, reducing the use amount of concrete, steel and the like, and arranging stress points of the dry dust removing device at the inner wall after the stress state of the inner wall of the tower is improved, correspondingly reducing the size of equipment, reducing the unnecessary steel consumption and saving a large amount of resources.

2. The utility model optimizes the structure between the granulating stations, so that the bottoms of the granulating stations are in an inverted truncated cone-shaped structure, the wind can conveniently flow through the urea liquid spraying device at the bottoms of the granulating stations, dead angles of heat transfer of original liquid drops are eliminated, the contact area between cooling wind from the bottom of the tower and urea liquid drops is enlarged, and more hot liquid drops can generate heat transfer and exchange with the cooling wind from the bottom of the tower at higher points relative to the ground. The effective travel height of urea liquid drops is increased, and the falling time of the urea liquid drops is prolonged, so that the temperature of granular urea falling to the bottom of the tower is effectively reduced.

Drawings

FIG. 1 is a schematic diagram of the structure of a urea prilling tower according to the present utility model.

Fig. 2 is a schematic structure of a urea prilling tower with a dry dust removal device according to the utility model.

Fig. 3 is a schematic structural diagram of a conventional urea prilling tower.

FIG. 4 is a schematic diagram of the air flow in a conventional urea prilling tower between prills.

Reference numerals in the drawings:

1 an outer layer tower body, 11 bottom ventilation holes; 2 ventilation spaces, 21 top ventilation holes; 3 a dry dust removing device, 31 a filter bag dust removing device, 32 a purifying device, 321 a blowing system and 33 a fan; 4, a granulating room, a 41 spraying device and a 42 overhaul space; 5 a collecting device, 51 a material carrying disc, 52 a scraping machine and 53 a conveying belt; 6, a shutter; 7, roof board; m urea granule shaping collecting zone, B urea sprays shaping district, C urea finished product collecting zone.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present utility model more apparent, the technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, for convenience of description, only the portions related to the present utility model are shown in the drawings. Embodiments of the utility model and features of the embodiments may be combined with each other without conflict.

It should be noted that the terms "first," "second," and the like herein are merely used for distinguishing between different devices, modules, or units and not for limiting the order or interdependence of the functions performed by such devices, modules, or units.

It should be noted that references to "one", "a plurality" and "a plurality" in this disclosure are intended to be illustrative rather than limiting, and those skilled in the art will appreciate that "one or more" is intended to be construed as "one or more" unless the context clearly indicates otherwise.

The names of messages or information interacted between the devices in the embodiments of the present utility model are for illustrative purposes only and are not intended to limit the scope of such messages or information.

As shown in fig. 1, there is provided a urea prilling tower structure, comprising an outer tower body 1, a ventilation room 2 is connected to the top in the outer tower body 1, a dry dust removing device 3 communicating with the ventilation room 2 is arranged at the top end of the ventilation room 2, the dry dust removing device 3 comprises a filter bag dust removing device 31 positioned at the top end of the ventilation room 2, and a suction fan 33 positioned at the top end of the filter bag dust removing device 31 and communicating with the filter bag dust removing device 31. And the bottom end of the ventilation room 2 is provided with a granulation room 4 communicated with a urea granule forming and collecting area M at the inner bottom of the outer tower body 1, wherein, for convenience of description, the urea granule forming and collecting area M is a heat exchange area at the bottom of the granulation room 4, and comprises a urea spray forming area B near the top and a urea finished product collecting area C near the bottom.

The wall body of the ventilation room 2 is provided with a plurality of top ventilation holes 21 communicated with the urea particle forming collecting area M, the top ventilation holes 21 are arranged on the wall body of the granulation room 4 in a vertical mode, the top ventilation holes 21 are round holes and/or kidney-shaped holes, namely, can be round holes, kidney-shaped holes or combination of the round holes and the kidney-shaped holes, and the top ventilation holes 21 are vent holes without movable windows, namely, common ventilation holes, and a shutter does not need to be installed. Similarly, a collecting device 5 is further arranged on the outer layer tower body 1 at the bottom side of the urea particle forming collecting area M, and a plurality of bottom ventilation holes 11 are further arranged on the outer layer tower body 1 at the upper side of the collecting device 5. The collecting device 5 comprises a funnel-shaped material tray 51, a scraper 52 arranged on the top side of the upper mouth of the material tray 51, and a conveyor belt 53 arranged on the bottom side of the lower mouth of the material tray 51. The bottom vent 11 is a circular hole and/or a kidney-shaped hole, and the bottom vent 11 is a vent without movable window, which is the same as the design principle of the top vent. The plurality of top vent holes 21 or bottom vent holes 11 are arranged in a staggered manner in the lateral or vertical direction.

That is, as shown in fig. 1, the louver 6 at the original top plenum 2 and at the bottom of the outer tower body 1 shown in fig. 3 is removed, and is changed into a smaller round or kidney-shaped vent without movable window. The reason is that the natural ventilation urea prilling tower before the dry dust collector 3 is additionally arranged adjusts the air inlet quantity according to the ambient temperature and the output by adjusting the angle of the louver 6. However, after the dry dust collector 3 is additionally installed on the top, the forced ventilation mode of the fan 33 is adopted, and the quantity of the running fans 33 is adjusted according to the ambient temperature and the yield to adjust the air inlet quantity. The original top louver 6 and bottom louver 6 are therefore functionally redundant after the dry dust removal device 3 is used.

Wherein, the top shutter 6 is provided with a plurality of holes on the wall in the tower body for installing the fixed shutter 6, which has great influence on the bearing capacity of the inner wall. When the dry dust collector 3 is added, the strength of the tower body can not meet the requirement of the weight of newly installed equipment; the stress points are required to be arranged at the outer wall, so that a large amount of unnecessary steel is added to the dry dust removing device 3, and the waste of resources is caused. And, the bottom louver 6 needs to open a plurality of holes at the bottom of the outer layer tower body 1, the outer layer tower body 1 is a bearing wall body of the tower, so that the overall stress condition of the tower is greatly affected, and when the louver 6 is installed by opening large rectangular holes, the bearing capacity of the tower needs to be improved by increasing the thickness of the tower body and other modes; and the weight of the shutter 6 also has a certain influence on the stress condition of the tower body, so that the thickness of the tower body is increased to improve the stress of the tower body, and a great amount of resource waste can be caused.

Therefore in this scheme, as shown in fig. 3, top shutter 6 and bottom shutter 6 have been cancelled, the rectangular hole of original installation shutter 6 is changed into smaller circular or kidney-shaped hole, only need satisfy basic intake can, single trompil area and trompil total area all reduce before, can improve the atress condition of tower body, and further, the mode that staggers the arrangement in horizontal or vertical is adopted in a plurality of top ventilation holes 21 that will set up in this scheme and bottom ventilation hole 11, in order to prevent that the trompil is too much in a direction of tower body, can further improve the atress condition of tower body, improve the bulk strength of tower. On one hand, the thickness of the tower wall can be reduced, and the use amount of concrete, steel and the like can be reduced; on the other hand, the inner wall of the ventilation room 2 has better bearing capacity, the dry dust removing device 3 can be arranged on the inner wall, the size of the equipment is correspondingly reduced, the unnecessary steel consumption is reduced, and a large amount of resources are saved.

And as shown in fig. 1, the bottom of the granulation chamber 4 is gradually contracted from top to bottom. Preferably, the bottom of the granulation chamber 4 is in an inverted truncated cone shape, a spraying device 41 is arranged on the lower bottom surface of the inverted truncated cone-shaped bottom of the granulation chamber 4, a nozzle of the spraying device 41 is arranged on the bottom side of the granulation chamber 4, and an overhaul space 42 is reserved on the lower bottom surface.

In the urea production process, it is known that in order to produce granular urea, the urea solution is concentrated to 99.7 mass% and then pumped via the molten urea to the urea liquid spray device 41 at the top of the urea prilling tower. During granulation, molten urine (132 ℃) is thrown out from the upper section of the urea granulation tower in a tangential direction under the action of centrifugal force by a urea liquid spray device 41, and the higher the rotating speed is, the larger the aperture is, and the farther the throwing distance is. The urine thrown out is naturally segmented by air in the descending process under the pulling action of cooling air, molten liquid drops are formed at the upper part of the tower body, and the thermal liquid drops and the cooling air from the tower bottom generate mass and heat transfer exchange; the gradually cooled surface of the liquid drop is contracted and naturally forms a sphere, and meanwhile, the cooling air is heated up.

The falling speed is far lower than the free falling speed at the upper position of the tower due to the typical 'hot ball' effect, the falling speed gradually increases along with the falling of the 'hot ball' temperature, and finally the falling speed is stable (about 9-12 m/s) due to the air resistance and the boundary effect of the particle surface. The urea prilling tower is naturally ventilated, and the effective height is about 50-60 m. The granular urea falling to the bottom of the tower is sent to an automatic weighing machine through a rotary scraper 52 to a conveyer belt 53, and finally sent to a urea warehouse.

Therefore, in the conventional urea prilling tower structure, as shown in fig. 4, the bottom of the urea prilling tower is flat, the gap between the bottom and the outer wall of the tower body is small, a large amount of wind directly flows upward between the prilling room 4 and the outer layer tower body 1, dead angles are formed in a certain area around the spraying device 41, and no wind flows, so that heat transfer exchange of liquid drops cannot be performed.

In this embodiment, as shown in fig. 1, the bottom of the granulation room 4 is optimized into an inverted truncated cone shape with a wide upper part and a narrow lower part, and a minimum size maintenance space 42 required for maintenance and the like is left in addition to the shower device 41 provided on the bottom lower surface. The optimized structure can enlarge the flowing area of the air flow, greatly reduce dead angle areas around the urea liquid spraying device 41, enlarge the contact area of cooling air from the bottom of the tower and urea liquid drops, and enable more hot liquid drops to generate heat transfer exchange with the cooling air from the bottom of the tower at a higher point relative to the ground. The effective travel height is increased for the liquid drops, which is beneficial to delaying the drop time, so that the temperature of the granular urea falling to the bottom of the tower is effectively reduced. Therefore, the required ventilation quantity can be greatly reduced under the condition of keeping the temperature of the granular urea at the bottom of the tower unchanged, the number of corresponding running fans 33 can be reduced, and the energy consumption is reduced.

And, in order to further improve the stress condition of the inner wall body at the position of the ventilation room 2 and reduce the resource waste. As shown in FIG. 2, the top fan 33 can be arranged in the grain-making room 4 and communicated with the top ventilation hole 21 on the ventilation room 2 to introduce air, so that the influence of resistance caused by a filter bag when the fan 33 is arranged at the top of the dry dust removing device 3 is avoided, the running power of the fan 33 can be greatly reduced, the energy consumption is saved, meanwhile, the fan 33 with a lower power consumption and a smaller model can be selected, and the stress condition of a wall body can be correspondingly improved. In addition, as shown in fig. 2, after the fan 33 at the top of the dry dust removing device 3 is arranged in the ventilation room 2, the original purifying device 32 of the dry dust removing device 3 is released, the dry dust removing device can be modified into an open type, the pattern plate of the original sealing purifying device 32 is removed, only one layer of pattern plate at the top is reserved for hanging and fixing the filter bag, the filter bag is placed under the influence of rain and snow, and a foldable roof 7 is arranged at the top of the pattern plate for shielding the rain and snow. A blowing system 321 is provided between the pattern plate and the ceiling 7 for cleaning the filter bag.

According to the optimized urea prilling tower, after the dry dust removal device is additionally arranged, the environment is protected, the standard is reached (far higher than the existing national standard), the waste of resources can be greatly reduced, the energy consumption is reduced, and the energy conservation, the emission reduction and the environmental protection are realized.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims (8)

1. The utility model provides a urea prilling tower structure, it includes outer tower body (1), the top connection in this outer tower body (1) is provided with ventilation room (2), characterized in that, the top of ventilation room (2) is provided with dry dust collector (3) with this ventilation room (2) intercommunication, and the bottom of this ventilation room (2) is provided with the grain room (4) with urea granule shaping collection zone (M) intercommunication of the inner bottom of outer tower body (1), be provided with a plurality of top ventilation holes (21) with urea granule shaping collection zone (M) intercommunication on the wall body of this ventilation room (2), and the bottom of this granulation room (4) is from top to bottom shrink gradually; the fan at the top is arranged in the granulation room.

2. Urea prilling tower structure according to claim 1, characterized in that the top vent (21) is a circular hole and/or a kidney-shaped hole, and the top vent (21) is a vent without movable window.

3. Urea prilling tower structure according to claim 1, characterized in that the bottom of the prilling room (4) is of inverted circular-cone shape, a spraying device (41) is arranged on the lower bottom surface of the inverted circular-cone-shaped bottom of the prilling room (4), the nozzle of the spraying device (41) is arranged at the bottom side of the prilling room (4), and an overhaul space (42) is reserved on the lower bottom surface.

4. A urea prilling tower structure according to claim 1, characterized in that the outer tower body (1) at the bottom side of the urea granule forming and collecting zone (M) is provided with a collecting device (5), and the outer tower body (1) at the upper side of the collecting device (5) is further provided with a plurality of bottom ventilation holes (11).

5. A urea prilling tower structure according to claim 4, characterized in that the bottom vent (11) is a circular hole and/or a kidney-shaped hole, and the bottom vent (11) is a vent without movable window.

6. Urea prilling tower structure according to claim 5, characterized in that the collecting device (5) comprises a funnel-shaped receiving disc (51), a scraper (52) being arranged at the top side of the upper mouth of the receiving disc (51), and a conveyor belt (53) being arranged at the bottom side of the lower mouth of the receiving disc (51).

7. A urea prilling tower structure according to any of claims 1, 2, 4 and 5, characterized in that the top vents (21) or the bottom vents (11) are staggered in the lateral or vertical direction.

8. A urea prilling tower structure according to claim 1, characterized in that the dry dust removal device (3) comprises a filter bag dust removal device (31) at the top end of the plenum (2), and a suction fan (33) at the top end of the filter bag dust removal device (31) in communication with the filter bag dust removal device (31).

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