Sulfur foam treatment system

Abstract

The utility model discloses a sulfur foam treatment system and belongs to the technical field of sulfur foam treatment. The device comprises a foam tank, a centrifugal machine, a sulfur melting kettle, a sulfur tank, a clear liquid tank, a spray cooling tower and a tail gas treatment device, a sulfur foam outlet of the foam tank is connected with an inlet of the centrifugal machine through a pump; a liquid outlet of the centrifugal machine is connected with the clear liquid tank, and a slag outlet is connected with an inlet of the sulfur melting kettle; a sulfur outlet of the sulfur melting kettle is connected with a sulfur tank, and an exhaust port is connected with an air inlet in the lower part of the spray cooling tower; gas outlets of the foam tank, the sulfur tank, the clear liquid tank and the spray cooling tower are connected with a tail gas treatment device through a fan. The device has the advantages of being stable and continuous in operation, reducing waste gas emission and improving the utilization rate of water resources.

Description

Technical Field

[0001] The utility model belongs to the technical field of sulfur foam treatment, and more specifically relates to a sulfur foam treatment system. Background Art

[0002] At present, the coking industry generally adopts ammonia wet oxidation desulfurization process with HPF, PDS and other catalysts to remove hydrogen sulfide and hydrogen cyanide in coke oven gas. The ammonia wet oxidation desulfurization and decyanation process will produce desulfurization waste liquid and sulfur foam containing ammonium thiocyanate and ammonium thiosulfate. How to improve the coking desulfurization effect, reduce the hydrogen sulfide content in coal gas, reduce sulfur emissions, and deal with desulfurization waste liquid and sulfur foam has always been an environmental problem that has plagued coking enterprises.

[0003] The water content of the sulfur foam generated at the top of the desulfurization regeneration tower is generally above 95%, and it needs to be concentrated to recover the desulfurization clear liquid containing ammonia and catalyst, and the suspended sulfur is concentrated into a sulfur paste with a certain water content. The sulfur paste is difficult to use directly and needs further treatment. At present, the sulfur foam treatment methods include plate and frame filter press + intermittent sulfur melting and sulfur melting kettle directly into the sulfur foam sulfur melting.

[0004] Among them, the plate and frame filter press + intermittent sulfur melting method has the disadvantages of discontinuous production operation, high labor intensity of material transfer, and strong odor of ammonia-containing waste gas on site. In the method of directly feeding sulfur foam into the sulfur melting kettle, since the room temperature sulfur foam is heated by steam, the clear liquid must be cooled to room temperature, which will waste a lot of steam and cooling water. At the same time, the suspended sulfur particles contained in the clear liquid returning to the system have been heated into mature sulfur particles, and sulfur foam can no longer be formed in the regeneration tower, which is very easy to block the equipment and the packing in the tower. In addition, when the molten sulfur is collected, cooled and the clear liquid is discharged, a large amount of ammonia-containing waste gas will be emitted, causing pollution to the atmosphere and the surrounding environment.

[0005] For example, the Chinese patent application number is CN201010192711.5, and the publication date is December 7, 2011, which discloses a method and equipment for producing molten sulfur from sulfur foam. In this method, sulfur foam is sent into a sulfur melting device through a delivery pump, and after being preheated and heated in the upper heat exchange section, it enters the middle sedimentation section for sedimentation and separation into desulfurization liquid and concentrated sulfur paste. The high-temperature desulfurization liquid returns to the desulfurization system after heat exchange and cooling upward, and the separated concentrated sulfur paste is discharged after being heated to form molten sulfur. The equipment consists of a delivery pump and a sulfur melting device, and the sulfur melting device includes an upper heat exchange section and a lower heating section, and a sedimentation and separation section is also provided between the two. The sulfur melting device is provided with a desulfurization liquid output pipeline and a heating medium pipeline, and a sulfur discharge valve is installed at the bottom of the heating section. This scheme is the aforementioned method of directly feeding sulfur foam into the sulfur melting kettle for sulfur melting, which has problems such as waste of steam and cooling water, blockage, and emission of waste gas.

[0006] For example, the Chinese patent application number is: CN202020933851.2, and the patent document with the publication date of January 29, 2021, discloses an intelligent intermittent sulfur melting and waste gas treatment integrated system, which is designed in the field of desulfurization technology, including a sulfur melting kettle, and the feed port at the upper end of the sulfur melting kettle is connected to the sulfur paste funnel, and the upper end of the sulfur paste funnel is connected to the discharge end of the plate and frame filter press, and the feed port of the plate and frame filter press is connected to the foam tank, the lower end of the sulfur melting kettle is connected to the exhaust gas collecting hood, and the upper end of the exhaust gas collecting hood is connected to the exhaust gas absorption tower, and the upper end of the sulfur melting kettle is also connected to the exhaust gas absorption tower, and a sulfur trolley is provided below the discharge end of the exhaust gas collecting hood. The utility model uses automated remote technology to realize the interlocking of the sulfur foam liquid level in the foam tank with the foam pump switch, and controls the automatic feeding of sulfur foam; the foam pump, the plate and frame filter press feed switch, and the clear liquid reflux are interlocked to control the plate and frame filter press filtration; sulfur emission and waste gas emission are interlocked with the waste gas treatment device to ensure that the waste gas treatment gas emission meets the standard, and realize the automation of the sulfur melting process and waste gas treatment. This solution is the plate and frame filter press + intermittent sulfur melting method mentioned above, which has the disadvantages of discontinuous production operation, high labor intensity of material transfer, and strong odor of ammonia-containing waste gas on site. Summary of the invention

[0007] 1. Problems to be solved

[0008] In view of the problem that the treatment effect of the prior art on desulfurization waste liquid and sulfur foam is not ideal, the utility model provides a sulfur foam treatment system, which has the advantages of stable and continuous operation, reduced waste gas emissions and improved water resource utilization.

[0009] 2. Technical solution

[0010] To solve the above problems, the utility model adopts the following technical solutions.

[0011] A sulfur foam treatment system comprises a foam tank, a centrifuge, a sulfur melting kettle, a sulfur tank, a clear liquid tank, a spray cooling tower and a tail gas treatment device; the sulfur foam outlet of the foam tank is connected to the inlet of the centrifuge through a pump; the liquid discharge port of the centrifuge is connected to the clear liquid tank, and the slag discharge port is connected to the inlet of the sulfur melting kettle; the sulfur outlet of the sulfur melting kettle is connected to the sulfur tank, and the exhaust port is connected to the air inlet of the lower part of the spray cooling tower; the air outlets of the foam tank, the sulfur tank, the clear liquid tank and the spray cooling tower are connected to the tail gas treatment device through a fan.

[0012] As a further improvement of the technical solution, the water outlet of the clear liquid tank is connected to the spray device in the spray cooling tower through a pump, and the condensed water outlet of the spray cooling tower is connected to the water inlet of the clear liquid tank.

[0013] As a further improvement of the technical solution, the spray device in the spray cooling tower includes at least two rows of spray heads respectively arranged at the upper part and the middle part of the spray cooling tower.

[0014] As a further improvement of the technical solution, a cooling coil is arranged in the clear liquid tank, and the inlet and outlet of the cooling coil are respectively connected to a water source.

[0015] As a further improvement of the technical solution, a heating coil is provided in the sulfur melting kettle, and the heating coil is externally connected to a steam source.

[0016] As a further improvement of the technical solution, a jacket with a cavity is provided on the side wall of the molten sulfur kettle, and a steam inlet connected to an external steam source is provided on the jacket.

[0017] As a further improvement of the technical solution, the centrifuge is a horizontal screw centrifuge.

[0018] As a further improvement of the technical solution, the exhaust gas treatment device includes at least two spray dust reduction towers connected in sequence.

[0019] As a further improvement of the technical solution, the water outlet at the bottom of the spray dust reduction tower is connected to the spray device in the spray dust reduction tower through a pump.

[0020] As a further improvement of the technical solution, the spray device in the spray dust reduction tower includes at least three rows of nozzles respectively arranged at the upper part, middle part and lower part of the spray dust reduction tower.

[0021] 3. Beneficial effects

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] (1) The utility model provides a sulfur foam treatment system, which separates the sulfur foam into a clear liquid and a sulfur paste with a certain water content through a centrifuge. The sulfur paste has a certain fluidity and can be smoothly loaded into a sulfur melting kettle, so that the centrifuge pre-dehydration method has the advantages of stable and continuous operation. At the same time, due to the pre-dehydration of the sulfur foam, the waste of steam and cooling water in the sulfur melting kettle can be reduced. In addition, the tail gas treatment device can purify the tail gas by dust reduction, avoid the emission of secondary pollutant gases, and improve the environmental protection effect;

[0024] (2) The utility model provides a sulfur foam treatment system, in which the clear liquid in the clear liquid tank can be sprayed with cooling water of the cooling tower for recycling, thereby improving the utilization efficiency of water resources. By arranging a cooling coil in the clear liquid tank, the clear liquid temperature in the clear liquid tank can be reduced, thereby ensuring the cooling effect of the spray cooling tower on the exhaust gas of the molten sulfur kettle;

[0025] (3) The utility model provides a sulfur foam treatment system, in which a heating coil is arranged in the sulfur melting kettle, which can ensure the heating efficiency of the sulfur melting kettle, and a jacket through which steam can be introduced is arranged on the side wall of the sulfur melting kettle, so that the sulfur melting kettle can be kept warm after being heated to a certain temperature, ensuring that the sulfur paste in the sulfur melting kettle can be smoothly melted and layered;

[0026] (4) The utility model provides a sulfur foam treatment system, wherein the tail gas treatment device comprises at least two spray dust reduction towers connected in sequence, which can effectively improve the dust reduction and purification effect of the tail gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the processing system of the utility model;

[0028] In the figure: 1. Foam tank; 2. Centrifuge; 3. Molten sulfur kettle; 4. Sulfur tank; 5. Clear liquid tank; 6. Spray cooling tower; 7. Fan; 8. Spray dust suppression tower. DETAILED DESCRIPTION

[0029] Exemplary embodiments of the present invention are described in detail below. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to implement the present invention, it should be understood that other embodiments may be implemented and various changes may be made to the present invention without departing from the spirit and scope of the present invention. The more detailed description of the embodiments of the present invention below is not intended to limit the scope of the claimed present invention, but is merely for illustration and does not limit the description of the features and characteristics of the present invention, in order to propose the best way to perform the present invention, and is sufficient to enable those skilled in the art to implement the present invention. Therefore, the scope of the present invention is limited only by the appended claims.

[0030] Example 1

[0031] A sulfur foam treatment system is used in the coking desulfurization process to treat sulfur foam and produce sulfur. Its specific structure and working process are described in detail below.

[0032] like Figure 1 As shown, the system mainly includes a foam tank 1, a centrifuge 2, a molten sulfur kettle 3, a sulfur tank 4, a clear liquid tank 5, a spray cooling tower 6 and a tail gas treatment device. Among them, the sulfur foam outlet of the foam tank 1 is connected to the inlet of the centrifuge 2 through a pump, the discharge port of the centrifuge 2 is connected to the clear liquid tank 5, and the paste discharge port is connected to the inlet of the molten sulfur kettle 3. The sulfur outlet of the molten sulfur kettle 3 is connected to the sulfur tank 4, and the exhaust port is connected to the air inlet at the bottom of the spray cooling tower 6. The water outlet of the clear liquid tank 5 is connected to the spray device in the spray cooling tower 6 through a pump, and the condensed water outlet of the spray cooling tower 6 is connected to the water inlet of the clear liquid tank 5, which improves the utilization efficiency of water resources. At the same time, the air outlets of the foam tank 1, the sulfur tank 4, the clear liquid tank 5 and the spray cooling tower 6 are connected to the tail gas treatment device through the fan 7.

[0033] The sulfur foam is separated into a clear liquid and a sulfur paste with a certain water content by a centrifuge 2. The sulfur paste has a certain fluidity and can be smoothly loaded into the sulfur melting kettle, so that the pre-dehydration method of the centrifuge 2 has the advantages of stable and continuous operation. At the same time, due to the pre-dehydration of the sulfur foam, the waste of steam and cooling water in the sulfur melting kettle 3 can be reduced. The tail gas treatment device can purify the tail gas by dust reduction, avoid the emission of secondary pollutant gases, and improve the environmental protection effect.

[0034] Specifically, the tail gas treatment device includes at least two spray dust reduction towers 8 connected in sequence, and in this embodiment, there are two, and the water outlet at the bottom of the spray dust reduction tower 8 is connected to the spray device in the spray dust reduction tower 8 through a pump. This multi-stage tail gas dust reduction purification device can effectively improve the dust reduction purification effect of the tail gas, and the circulation and spraying of the clean water in the spray dust reduction tower 8 improves the utilization efficiency of water resources of the whole system.

[0035] In this embodiment, in order to ensure the cooling effect of the spray cooling tower 6 and the exhaust gas purification effect of the spray dust tower 8, the spray device in the spray cooling tower 6 includes at least two rows of nozzles respectively arranged at the upper and middle parts of the spray cooling tower 6, and in this embodiment, one row of nozzles is respectively arranged at the upper and middle parts, and the spray device in the spray dust tower 8 includes at least three rows of nozzles respectively arranged at the upper, middle and lower parts of the spray dust tower 8, and in this embodiment, one row of nozzles is respectively arranged at the upper, middle and lower parts. At the same time, a cooling coil is arranged in the clear liquid tank 5, and the inlet and outlet of the cooling coil are respectively connected to the water source, that is, the temperature of the clear liquid in the clear liquid tank 5 is reduced by circulating cooling water in the cooling coil, thereby further ensuring the cooling effect of the spray cooling tower 6.

[0036] In addition, a heating coil is provided in the sulfur melting kettle 3, and the heating coil is connected to an external steam source. At the same time, a jacket with a cavity is provided on the side wall of the sulfur melting kettle 3, and a steam inlet connected to an external steam source is provided on the jacket. The heating coil is passed with steam to ensure the heating efficiency of the sulfur melting kettle, and the steam is passed into the outer jacket of the sulfur melting kettle 3, so that the sulfur melting kettle 3 can be heated to a certain temperature and kept warm, so as to ensure that the sulfur paste in the sulfur melting kettle 3 can be smoothly melted and layered.

[0037] like Figure 1 As shown, the specific working process of the system is as follows.

[0038] Step 1, centrifuge 2 is used for centrifugal dehydration to process sulfur foam to produce sulfur paste. In this embodiment, centrifuge 2 is a conventional horizontal screw centrifuge on the market, which utilizes the different densities of suspended sulfur and clear liquid in sulfur foam to separate the clear liquid and suspended sulfur in centrifuge 2 in layers to achieve the purpose of separation.

[0039] The specific operation is to transport the sulfur foam in the sulfur foam tank 1 to the drum of the centrifuge 2 with a set flow rate by a foam pump, and the tail gas of the foam tank 1 is discharged from the top and connected to the inlet of the fan 7 in front of the tail gas treatment device. After the drum rotates, due to the high density of the suspended sulfur, the centrifugal force generated is also large, and the centrifugal force forces the suspended sulfur to quickly deposit on the drum, while the clear liquid stays in the center of the drum. The nearly solid sulfur paste deposited on the inner wall of the drum is scraped off by the spiral scraper in the drum and transported to the slag discharge port for discharge. The clear liquid is controlled by the support baffle at the other end of the centrifuge 2 and discharged from the overflow port to the clear liquid tank 5.

[0040] In the centrifuge 2, the operation of the drum is driven by the main motor, and the operation of the spiral scraper is driven by the differential motor. The moisture content of the sulfur paste can be adjusted by adjusting the speed and the height of the overflow baffle. The speed adjustment of the horizontal screw centrifuge is controlled by a frequency converter, and the moisture content of the sulfur paste is adjusted to about 40%. The centrifuge enters the clear liquid tank 5.

[0041] Step 2, the sulfur paste with a moisture content of 40% produced by centrifuge 2 is loaded into the sulfur melting kettle 3 through a pipeline. The heating coil in the sulfur melting kettle 3 is heated with 0.6Mp low-pressure steam, and the outer jacket is kept warm by steam. It is heated to 140°C by indirect steam and kept warm for 4 hours. After the sulfur paste in the kettle is melted and stratified, the gas and water vapor generated are discharged from the upper part of the sulfur melting kettle 3, and the crude sulfur produced at the lower part is discharged into the sulfur tank 4. The sulfur tank 4 is equipped with a gas collecting pipe to collect the tail gas generated by the sulfur discharge and send it to the tail gas treatment device for treatment, without odor leakage.

[0042] Step 3, the water in the sulfur paste in the sulfur melting kettle 3 is heated to become steam, and is discharged to the spray cooling tower 6 through the exhaust valve of the sulfur melting kettle 3 with the non-condensable gas, and enters from the bottom of the spray cooling tower 6. The spray cooling tower 6 is provided with nozzles at the top and middle of the spray cooling tower 6. The clear liquid at about 35°C in the clear liquid tank 5 is transported to the top and middle of the spray cooling tower 6 by a circulating pump, and the clear liquid is transported to the top and middle of the spray cooling tower 6 for spraying, and is countercurrently contacted with the water vapor and non-condensable gas from the sulfur melting kettle 3, and the water vapor and non-condensable gas discharged from the sulfur melting kettle are cooled, and the impurities such as ash discharged with the gas are purified at the same time. The cooled water vapor condenses into clear liquid, and flows to the clear liquid tank 5 through the lower reflux pipe with the cooling water for recycling. The tail gas of the spray cooling tower 6 is discharged from the top and connected to the inlet of the fan 7 in front of the tail gas treatment device. The coil in the clear liquid tank 5 is cooled by circulating cooling water, maintained at 35°C, and a certain liquid level is maintained.

[0043] Step 4, the tail gas treatment device adopts a two-stage spray device, the first and second stage spray dust reduction towers 8 each use a pump for self-circulation spraying, and the spray tower adopts upper, middle and lower three rows of nozzles.

[0044] Step 5: Complete the treatment of sulfur foam and the production of sulfur.

[0045] In summary, the sulfur foam treatment system of this embodiment has the advantages of stable and continuous operation, reduced exhaust gas emissions and improved water resource utilization.

Claims

1. A sulfur foam treatment system, Features: The invention comprises a foam tank (1), a centrifuge (2), a molten sulfur kettle (3), a sulfur tank (4), a clear liquid tank (5), a spray cooling tower (6) and a tail gas treatment device; the sulfur foam outlet of the foam tank (1) is connected to the inlet of the centrifuge (2) through a pump; the liquid discharge port of the centrifuge (2) is connected to the clear liquid tank (5), and the slag discharge port is connected to the inlet of the molten sulfur kettle (3); the sulfur outlet of the molten sulfur kettle (3) is connected to the sulfur tank (4), and the exhaust port is connected to the air inlet of the lower part of the spray cooling tower (6); the air outlets of the foam tank (1), the sulfur tank (4), the clear liquid tank (5) and the spray cooling tower (6) are connected to the tail gas treatment device through a fan (7).

2. A sulfur foam treatment system according to claim 1, Features: The water outlet of the clear liquid tank (5) is connected to a spray device in a spray cooling tower (6) via a pump, and the condensed water outlet of the spray cooling tower (6) is connected to the water inlet of the clear liquid tank (5).

3. A sulfur foam treatment system according to claim 2, Features: The spray device in the spray cooling tower (6) comprises at least two rows of spray heads respectively arranged at the upper part and the middle part of the spray cooling tower (6).

4. A sulfur foam treatment system according to claim 3, Features: A cooling coil is arranged in the clear liquid tank (5), and the inlet and outlet of the cooling coil are respectively connected to a water source.

5. A sulfur foam treatment system according to claim 1, Features: A heating coil is arranged in the sulfur melting kettle (3), and the heating coil is externally connected to a steam source.

6. A sulfur foam treatment system according to claim 5, Features: A jacket with a cavity is provided on the side wall of the molten sulfur kettle (3), and a steam inlet connected to an external steam source is provided on the jacket.

7. A sulfur foam treatment system according to any one of claims 1 to 6, Features: The centrifuge (2) is a horizontal screw centrifuge.

8. A sulfur foam treatment system according to any one of claims 1 to 6, Features: The tail gas treatment device comprises at least two spray dust reduction towers (8) connected in sequence.

9. A sulfur foam treatment system according to claim 8, Features: The water outlet at the bottom of the spray dust reduction tower (8) is connected to the spray device in the spray dust reduction tower (8) through a pump.

10. A sulfur foam treatment system according to claim 9, Features: The spray device in the spray dust reduction tower (8) comprises at least three rows of spray heads respectively arranged at the upper part, the middle part and the lower part of the spray dust reduction tower (8).

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