CN106377968A - Dust removing and recycling system for granulation column - Google Patents

Abstract

The present invention is mainly applied to the field of multi-purpose granulation tower top dust recovery device and recovery method, and particularly relates to a granulation tower dust removal and reuse device, including a liquid collection circulation system and a dust recovery chamber, and the liquid collection circulation system includes a liquid collection tank , the liquid collection tank is located below the secondary spray atomization absorption device, the bottom of the liquid collection tank is provided with a feeding pipe, and the feeding pipe is respectively connected to the ammonium nitrate circulation tank and the nitro fertilizer circulation tank through a tee, and the ammonium nitrate circulation tank and the nitro fertilizer The bottom of the circulation tank is connected with the discharge pipe, and the discharge pipe is connected with the circulation pump and the temperature-adjusting heat exchanger in sequence according to the discharge direction. The upper part and the bottom of the nitro fertilizer circulation tank are connected with the liquid pipe of the nitro fertilizer. Both the upper and the bottom of the tank are connected with the ammonium nitrate lower liquid pipe, and the replenishment spray device is respectively connected with the upper water pipe and the discharge pipe through the tee. The invention has simple technological process and convenient operation, and the dust removal rate can reach more than 92%, which can greatly reduce the influence of the carried out dust on the surrounding environment.

Description

Pelletizing Tower Dust Recycling Device

technical field

The invention relates to a dust removal and recycling device for a granulation tower, which is mainly used in the field of a dust recovery device and a recycling method at the top of a multipurpose granulation tower.

Background technique

After the State Council General Office (2002) No. 52 "Notice on Further Strengthening the Safety Management of Civilian Explosives" was issued, the production and sales of agricultural ammonium nitrate products were stopped. The demand for ammonium nitrate has been greatly reduced, forcing ammonium nitrate production enterprises to seize the time to modify ammonium nitrate. Most enterprises have built multi-purpose granulation towers that can be used for both ammonium nitrate granulation and nitro compound fertilizer granulation. One tower It is multi-purpose, and can produce ammonium nitrate or nitro compound fertilizer in stages according to market needs.

Whether it is to produce ammonium nitrate, nitro compound fertilizer or other compound fertilizers, the concentrated ammonium nitrate solution is firstly pumped to the melting tank, and then sent from the melting tank to the porous nozzle or differential nozzle on the upper part of the prilling tower. Granulate. There is a 3m-high natural air duct between the vertical section of the tower and the lower funnel. The molten liquid is gradually cooled by the pressure difference sprayed from the nozzle and the gravity descending and rising air to form 2-4mm particles, which fall into the funnel to the belt. It is sent to the packaging section through the belt. There is a spraying device at 79m of the tower. When one product is replaced by another product, the spraying device can be turned on to clean the shell with clean water. After cleaning, turn off the spray device, and then air dry for use.

In the production process of the multi-purpose prilling tower, although the treatment of the tail gas of the prilling tower is not the main production link, the pros and cons of its process equipment and equipment operation have a great impact on the output, operation rate, material recovery rate, energy consumption level and environmental protection of the device. All have great influence. With many large and medium-sized nitro fertilizer enterprises expanding capacity and changing production on a large scale, environmental protection issues in the production process of nitro fertilizer have become increasingly prominent.

At present, the treatment method for the tail gas of the prilling tower is to use the circulating liquid to contact the exhaust gas of the prilling tower containing the granulated molten dust, so as to absorb the dust in the circulating liquid, and when the concentration reaches about 10%, it is recycled to the production system for further processing. Reuse. This treatment method has the following problems: firstly, after the dust is absorbed by water for one time, the dust content of the tower exhaust gas is still high, which does not meet the environmental protection standard, and it also causes a lot of material loss, resulting in waste of resources; secondly, it cannot Adjustment, respectively recovering ammonium nitrate and nitro fertilizer washing solution; the solution concentration of recycled materials is low, and the water content is high, and the water content of the nitro fertilizer product will be adversely affected after being reused in the production system.

Contents of the invention

The technical problem to be solved by the present invention is to provide a prilling tower dust removal recycling device with simple process flow, convenient operation, improved dust removal rate, and can greatly reduce the impact of the carried out dust on the surrounding environment.

The dust removal and recycling device of the granulation tower according to the present invention includes a liquid collection circulation system and a dust recovery room located on the upper part of the liquid collection circulation system. Cross-flow droplet collection and separation packing, primary jet atomization absorption device, baffle device and secondary jet atomization absorption device, liquid collection circulation system includes liquid collection tank, liquid collection tank is located in the secondary jet atomization absorption device Below, the bottom of the liquid collection tank is provided with a feeding pipe. The feeding pipe is respectively connected to the ammonium nitrate circulation tank and the nitro fertilizer circulation tank through a tee. Both the ammonium nitrate circulation tank and the bottom of the nitro fertilizer circulation tank are connected to the discharge pipe. The top is connected with the circulating pump and the temperature-adjusting heat exchanger in sequence according to the discharge direction. The upper part and the bottom of the nitro fertilizer circulation tank are connected with the lower liquid pipe of the nitro fertilizer, and the upper part and the bottom of the ammonium nitrate circulating tank are connected with the lower liquid pipe of the ammonium nitrate. The liquid replenishment spraying device is respectively connected with the upper water pipe and the discharge pipe through the tee, and the discharge pipe is respectively connected with the primary spray atomization absorption device and the secondary spray atomization absorption device.

The anti-drip protective wire mesh, baffle device and cross-flow droplet capture all play a role in filtering the exhaust gas.

The dust recovery chamber is set as a cylindrical dust recovery chamber.

The liquid replenishment spraying device includes a plurality of spraying pipes, and a plurality of spiral water curtain nozzles are installed on each spraying pipe.

The first-stage jet atomization absorption device and the second-stage jet atomization absorption device both include a plurality of water pipes, and each water pipe is equipped with a plurality of flat-mouth right-angle nozzles, and all water pipes are connected to the outlet pipe of the temperature-regulating heat exchanger.

The bottoms of the ammonium nitrate circulation tank and the nitro fertilizer circulation tank are respectively provided with concentration detection devices.

The bottom of the liquid collection tank is provided with a feeding pipe, and the lower end of the feeding pipe is respectively extended into the ammonium nitrate circulation tank and the nitro fertilizer circulation tank through a tee. and a concentration detection device, a circulating pump is installed on the discharge pipe of the circulating tank; the cylindrical dust recovery room is set on the top air outlet of the multi-purpose prilling tower, and the protective screen is removed from top to bottom in the recovery room , rehydration spray device, cross-flow droplet capture and separation packing, primary jet atomization absorption device, baffle device, secondary jet atomization absorption device, process waste liquid generated by rehydration spray device and main production device or The new supplementary water is connected, and it is connected with the temperature-regulating heat exchanger through the tee, the first and second-stage spray atomization absorption devices are connected with the temperature-regulating heat exchanger, and the temperature-regulating heat exchanger is connected with the outlet of the circulating pump; The shower pipe is connected with the process waste liquid or new supplementary water generated by the main production device through the water pipe. On-off valves can be set on each pipeline to facilitate the control of the connection and closure of each pipeline.

The exhaust gas of the multi-purpose granulation tower is discharged from the top of the tower and discharged into the atmosphere through the dust recovery room. The dust recovery device starts to work in the dust recovery room. When the multi-purpose granulation tower is used for nitro fertilizer granulation in the previous working condition, it is now ready When used for ammonium nitrate granulation, at the initial stage of work, there is no liquid or the liquid level is insufficient in the circulation tank. At this time, fresh water is supplied from the upper water pipe to the replenishment spraying device for spraying. The spraying of the replenishment spraying device can clean each separation packing layer And the spray device can also wash the exhaust gas. The fresh water for washing is collected by the liquid collection tank and discharged into the nitro fertilizer circulation tank through the tee of the feeding pipe; Spraying, collected by the liquid collection tank, and discharged into the ammonium nitrate circulation tank through the tee of the feeding pipe, the circulation pump starts to work to supply the spray liquid to the primary and secondary spray atomization absorption devices. When it rises to the set value, close the upper water pipe to stop the liquid supply to the replenishment spray device, the primary and secondary spray atomization absorption devices are all supplied by the circulation pump, forming a liquid replenishment spray device, primary and secondary spray atomization absorption devices , the liquid collection tank, the discharge pipe, and the internal circulation of the ammonium nitrate circulation tank; when the liquid in the ammonium nitrate circulation tank contains a high amount of ammonium nitrate, the liquid is discharged from the device through the ammonium nitrate lower liquid pipe, and the upper water pipe supplies liquid again .

When the multi-purpose prilling tower was used for ammonium nitrate granulation in the previous working condition, and now it is ready to be used for nitro fertilizer granulation, after washing the ammonium nitrate circulation tank, the waste liquid collected from the liquid collection tank is discharged into the ammonium nitrate circulation tank , Complete ammonium nitrate collection.

The beneficial effects of the present invention are:

1. The interior of the circulation tank is divided into two parts by a partition, namely the ammonium nitrate solution circulation tank and the nitro fertilizer solution circulation tank. According to the production adjustment, the ammonium nitrate and the dust in the tail gas of the nitro fertilizer can be recovered respectively;

2. Apply the three-stage absorption and three-stage separation process to ensure the dust removal effect and gas-water separation, and avoid the atomized washing liquid from being carried out of the prilling tower, causing secondary pollution;

3. When the circulating absorption liquid reaches a certain concentration, it is regularly recycled to the solution tank or evaporation system, which has little impact on the original production system and obvious recovery benefits;

4. The technological process is simple, the operation is convenient, and the dust removal rate can reach more than 92%, which can greatly reduce the impact of the dust brought out on the surrounding environment.

Description of drawings

Fig. 1 is a schematic structural view of the present invention.

In the figure: 1. Drip removal protection screen; 2. Primary jet atomization absorption device; 3. Baffle device; 4. Secondary jet atomization absorption device; 5. Feed pipe; 6. Ammonium nitrate circulation tank; 7. Nitro fertilizer circulation tank; 8. Nitro fertilizer lower liquid pipe; 9. Ammonium nitrate lower liquid pipe; 10. Discharge pipe; 11. Circulating pump; 12. Upper water pipe; 15. Fluid replenishment spray device; 16. Fluid collection tank.

detailed description

The present invention will be further described below in conjunction with accompanying drawing:

As shown in Figure 1, the dust removal and recycling device of the prilling tower according to the present invention is characterized in that it includes a liquid collection circulation system and a dust recovery chamber located on the upper part of the liquid collection circulation system, and the dust recovery chamber is sequentially arranged from top to bottom. Drop protection wire mesh 1, replenishment spray device 15, cross-flow droplet capture and separation packing 14, primary jet atomization absorption device 2, baffle device 3 and secondary jet atomization absorption device 4, liquid collection circulation system includes The liquid collecting tank 16, the liquid collecting tank 16 is positioned at the below of the secondary jet atomization absorbing device 4, the bottom of the liquid collecting tank 16 is provided with a feeding pipe 5, and the feeding pipe 5 is respectively connected to the ammonium nitrate circulation tank 6 and the nitro fertilizer circulation through a tee. Groove 7 is communicated, and the bottom of ammonium nitrate circulation tank 6 and nitrofertilizer circulation tank 7 is all communicated with discharge pipe, and discharge pipe 10 is connected with circulation pump 11 and temperature-regulating heat exchanger 13 successively according to the discharge direction, and nitrofertilizer circulation tank 7 The top and bottom of the tank are connected with the liquid pipe 8 of the nitro fertilizer, the top and the bottom of the ammonium nitrate circulation tank 6 are connected with the liquid pipe 9 of the ammonium nitrate, and the liquid replenishing spray device 15 is respectively connected with the upper water pipe 12 and the discharge pipe through a tee 10, and the discharge pipe 10 communicates with the primary jet atomization absorption device 2 and the secondary jet atomization absorption device 4 respectively. The dust recovery chamber is set as a cylindrical dust recovery chamber. The liquid replenishing spraying device 15 includes a plurality of spraying pipes, and a plurality of spiral water curtain nozzles are installed on each spraying pipe. The first-stage jet atomization absorption device 2 and the second-stage jet atomization absorption device 4 both include a plurality of water pipes, each of which is equipped with a plurality of flat-mouth right-angle nozzles, and all water pipes are connected with the temperature-regulating heat exchanger 13 outlet pipes. The bottoms of the ammonium nitrate circulation tank 6 and the nitro fertilizer circulation tank 7 are respectively provided with concentration detection devices.

The exhaust gas of the multi-purpose granulation tower is discharged from the top of the tower and discharged into the atmosphere through the dust recovery room. The dust recovery device starts to work in the dust recovery room. When the multi-purpose granulation tower is used for nitro fertilizer granulation in the previous working condition, it is now ready When used for ammonium nitrate granulation, at the initial stage of work, there is no liquid or the liquid level is insufficient in the circulation tank. At this time, fresh water is supplied from the upper water pipe 12 to the replenishment spraying device 15 for spraying. The spraying of the replenishment spraying device 15 can clean each Separating the packing layer and spraying device can also wash the exhaust gas. The fresh water for washing is collected by the liquid collection tank 16 and discharged into the nitro fertilizer circulation tank 7 through the tee of the feeding pipe; 12 Supply liquid replenishment spraying device 15 for spraying, collect by liquid collection tank 16, and discharge into ammonium nitrate circulation tank 6 respectively through the three-way connection of the feeding pipe, and circulation pump 11 starts to work for the first-level spray atomization absorption device 2, the second The first-stage spray atomization absorption device 4 supplies spray liquid. When the liquid level of the ammonium nitrate circulation tank 6 rises to the set value, the upper water pipe 12 is closed to stop the liquid supply to the replenishment spray device 15, the first-stage spray atomization absorption device 2, The secondary spray atomization absorption device 4 is all supplied with liquid by the circulation pump 11, forming a liquid replacement spray device 15, a primary spray atomization absorption device 2, a secondary spray atomization absorption device 4, a liquid collection tank 16, and a discharge pipe 10 , the internal circulation of the ammonium nitrate circulation tank 6; when the liquid in the ammonium nitrate circulation tank 6 contained ammonium nitrate amount was higher, the liquid was discharged from the device by the ammonium nitrate lower liquid pipe 9, and the upper water pipe 12 supplied liquid again simultaneously.

Claims (5)

1. a kind of granulation tower dedusting reclamation set it is characterised in that：Including collection fluid circulation with collection fluid circulation The dust recovery chamber in portion, in dust recovery chamber from top to bottom set gradually except drip protection silk screen (1), fluid infusion spray equipment (15), Cross-flow liquid droplet capture separation filler (14), one-level jet atomization absorption plant (2), baffle means (3) and two-stage injection atomization are inhaled Receiving apparatus (4), collection fluid circulation includes collecting tank (16), and collecting tank (16) is located at two-stage injection atomization absorption device (4) Lower section, collecting tank (16) bottom setting tremie pipe (5), it is fertile respectively at ammonium nitrate circulating slot (6), nitro that tremie pipe (5) passes through threeway Circulating slot (7) connects, and ammonium nitrate circulating slot (6) is all connected with discharge nozzle (10) with nitro fertilizer circulating slot (7) bottom, discharge nozzle (10) On be sequentially communicated circulating pump (11) and trim heat exchanger (13) according to discharging direction, the top of nitro fertilizer circulating slot (7) and bottom All fertile with nitro lower liquid pipe (8) connects, and the top of ammonium nitrate circulating slot (6) is all connected with liquid pipe under ammonium nitrate (9) with bottom, and fluid infusion is sprayed Shower device (15) is connected with upper hose (12), discharge nozzle (10) respectively by threeway, and discharge nozzle (10) sprays mist with one-level respectively Change absorption plant (2), two-stage injection atomization absorption device (4) connection.

2. granulation tower dedusting reclamation set according to claim 1 it is characterised in that：Dust recovery chamber is set to cylinder Dust recovery chamber.

3. granulation tower dedusting reclamation set according to claim 1 it is characterised in that：Fluid infusion spray equipment (15) includes many Root shower, every shower is installed multiple spiral drenchers.

4. granulation tower dedusting reclamation set according to claim 1 it is characterised in that：One-level jet atomization absorption plant (2), two-stage injection atomization absorption device (4) all includes many water pipes, and every water pipe is respectively mounted multiple flat mouth right angles shower nozzle, institute Water pipe is had all to be connected with trim heat exchanger (13) outlet.

5. granulation tower dedusting reclamation set according to claim 1 it is characterised in that：Ammonium nitrate circulating slot (6), nitro fertilizer follow Annular groove (7) inner bottom part is respectively provided with concentration detection apparatus.