阅读说明：本技术 硫磺湿法成型造粒生产系统及生产工艺 (Wet-process sulfur forming granulation production system and production process ) 是由 余智敏 于 2019-11-21 设计创作，主要内容包括：本发明涉及硫磺造粒技术领域,具体涉及一种硫磺湿法成型造粒生产系统及生产工艺。所述的硫磺湿法成型造粒生产系统,包括依次设置的液硫过滤器、液硫分布器、造粒主机、产品脱水振动筛和产品输送装置,液硫分布器上端还设置有排气装置,产品脱水振动筛下端还设置有冷却水处理一体池；所述冷却水处理一体池包括依次设置的浓缩池、入水池、沉淀池和清水池,所述浓缩池内设置有细粒螺旋提升装置,所述清水池内设置有pH监控装置。本发明的硫磺湿法成型造粒生产系统和生产工艺,生产的硫磺固体颗粒产品形状为球形、表面光滑、粒度均匀、不含任何硫磺粉尘、散装运输和装袋运输都不易起尘、并且表面水分含量极低。(The invention relates to the technical field of sulfur granulation, in particular to a sulfur wet-process forming granulation production system and a production process. The sulfur wet forming granulation production system comprises a liquid sulfur filter, a liquid sulfur distributor, a granulation host, a product dehydration vibrating screen and a product conveying device which are sequentially arranged, wherein an exhaust device is further arranged at the upper end of the liquid sulfur distributor, and a cooling water treatment integrated pool is further arranged at the lower end of the product dehydration vibrating screen; the cooling water treatment integrated pool comprises a concentration pool, a water inlet pool, a sedimentation pool and a clean water pool which are sequentially arranged, wherein a fine grain spiral lifting device is arranged in the concentration pool, and a pH monitoring device is arranged in the clean water pool. According to the wet-process sulfur molding granulation production system and the production process, the produced sulfur solid particle product is spherical, has a smooth surface and uniform particle size, does not contain any sulfur dust, is not easy to generate dust during bulk transportation and bagging transportation, and has extremely low surface moisture content.)

1. The wet-process sulfur forming and granulating production system is characterized in that: the device comprises a liquid sulfur filter (2), a liquid sulfur distributor (5), a granulation main machine (7), a product dehydration vibrating screen (14) and a product conveying device (15) which are arranged in sequence, wherein an exhaust device (4) is further arranged at the upper end of the liquid sulfur distributor (5), and a cooling water treatment integrated pool (25) is further arranged at the lower end of the product dehydration vibrating screen (14); the cooling water treatment integrated pool (25) comprises a concentration pool (18), a water inlet pool (21), a sedimentation pool (22) and a clean water pool (23) which are sequentially arranged, a fine grain spiral lifting device (19) is arranged in the concentration pool (18), and a pH monitoring device (26) is arranged in the clean water pool (23).

2. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the liquid sulfur filter (2) is arranged on a liquid sulfur conveying pipe (3) connected with a heat preservation steam pipe (1), and the tail end of the liquid sulfur conveying pipe (3) is arranged above the liquid flow distributor (5).

3. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the liquid sulfur distributor (5) comprises one or more liquid flow distributor units (29); the liquid flow distributor unit (29) comprises a main distributor (30) and a pre-distributor (33) arranged in the main distributor, wherein a plurality of small holes (32) with the diameter of 10-15mm are distributed on the four sides of the bottom of the pre-distributor (33), a plurality of small holes (31) with the diameter of 1-4mm are distributed on the bottom of the main distributor (30), and the distance between the circle centers of the adjacent small holes (31) is 6-30 mm; the small hole (31) of the main distributor (30) is in a structure of an upper cylindrical shape and a lower inverted circular truncated cone shape.

4. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the granulation main machine (7) is provided with a water inlet (8), an overflow port (6), a discharge port (12) and a glass window (9);

the water inlet (8) leads the process cooling water in the clean water tank into the granulation main machine (7) through a water inlet pipe;

the overflow port (6) leads part of overflowing process cooling water into the clean water tank (23) through an overflow pipe;

the discharge outlet (12) leads the solid sulfur particles and part of the process cooling water into the product dehydration vibrating screen (14) through a discharge pipe;

an image gray scale recognition camera (11) is installed on the glass window (9), and the image gray scale recognition camera (11) is connected with a pneumatic electric control valve (13) and an alarm device (10) which are installed on a material discharging pipe.

5. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the distance from the bottom surface of the liquid sulfur distributor (5) to the process cooling water overflow surface of the granulation main machine (7) is 10-70 mm.

6. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the product dehydration vibration screen (14) adopts a linear vibration screen, and the part which is contacted with the sulfur particle product and the process cooling water adopts stainless steel 304, 316 or 316L material; the upper part of the product dehydration vibrating screen (14) discharges the sulfur particle products to a product conveying device (15), and the bottom part discharges the process cooling water to a water tank (21) through a pipeline.

7. The system for producing sulphur by wet forming and granulation according to claim 1, wherein: the water inlet tank (21) leads the process cooling water into the concentration cyclone (16) through a water inlet tank water pump (20), a discharge port at the lower end of the concentration cyclone (16) leads into a fine grain spiral lifting device (19) of the concentration tank (18), and the tail end of the fine grain spiral lifting device (19) leads into a sulfur fine grain collecting container (17); a water outlet at the upper end of the concentration cyclone (16) is introduced into a sedimentation tank (22), supernatant of the sedimentation tank (22) is introduced into a clean water tank (23) through an overflow wall, the clean water tank (23) introduces recovered cooling water into a heat exchanger (27) through a clean water tank water pump (24), and the recovered cooling water is introduced into a granulation main machine (7) after heat exchange; the cold source medium of the heat exchanger (27) is cooled by a cooling tower (28).

8. A production process of the sulphur wet-forming granulation production system as defined in any one of claims 1 to 7, wherein: the method comprises the following steps:

(1) removing solid impurities from liquid sulfur through a liquid sulfur filter (2), generating uniformly distributed liquid sulfur lines from the liquid sulfur through a liquid flow distributor (5), introducing the liquid sulfur into a granulation host (7), generating sulfur liquid drops in process cooling water, and gradually cooling and solidifying the sulfur liquid drops into spherical solid sulfur particles; a glass window (9) arranged on a granulation host (7) converts a sulfur material level image gray scale signal into an electric signal of 4-20mA by using an image gray scale identification camera (11), and automatically adjusts a pneumatic electric control valve (13) arranged on a discharge pipe at the bottom of the granulation host, thereby controlling the discharge flow of solid sulfur particles of the granulation host (7), simultaneously controlling an alarm device (10) connected with the granulation host, and giving an alarm when the material level is higher than the highest material level or lower than the lowest material level;

(2) during granulation, part of process cooling water is discharged from an overflow port (6) at the top of a main granulation machine (7) and enters a clean water tank (23) through an overflow pipe, the rest of process cooling water and solid sulfur particles are discharged into a product dehydration vibrating screen (14) together for dehydration, the dehydrated sulfur particle products are conveyed to a product storage bin or a product packaging machine through a product conveying device (15), the removed recovered cooling water is discharged to a water inlet tank (21), the water inlet tank (21) leads the process cooling water into a concentration cyclone (16) through a water inlet tank water pump (20), sulfur fine particles in the process cooling water are recovered and discharged into a fine particle spiral lifting device (19) in a concentration tank (18) through the bottom, the sulfur fine particles are lifted and dehydrated from the concentration tank (18) and then lifted to a machine head to be discharged into a sulfur fine particle collecting container (17), the sulfur fine grain product is obtained after the short-time accumulation dehydration or the further dehydration of a fine grain dehydration device;

(3) introducing water obtained after sulfur fine particles are recovered from a concentration cyclone (16) into a sedimentation tank (22) for sedimentation, precipitating the ultrafine sulfur particles at the bottom, introducing supernatant into a clean water tank (23) through an overflow wall, introducing process cooling water into a heat exchanger (27) through a clean water tank water pump (24) in the clean water tank (23), and introducing the process cooling water into a granulation host (7) for reuse after heat exchange, wherein a cold source medium of the heat exchanger (27) is cooled through a cooling tower (28), and the pH value of the cooling water is controlled to be maintained within the range of 5.5-8.5 by the clean water tank (23) through a pH monitoring device (26).

9. The production process of the sulphur wet forming granulation production system according to claim 8, wherein: the liquid sulfur liquid level in the liquid sulfur distributor (5) is 5-40 mm.

10. The production process of the sulphur wet forming granulation production system according to claim 8, wherein: the product dehydration vibration sieve (14) is a linear vibration sieve, the double amplitude is 6-15mm, the linear ejection angle is 30-60 degrees, and the excitation frequency is 700-.

Technical Field

The invention relates to the technical field of sulfur granulation, in particular to a sulfur wet-process forming granulation production system and a production process.

Background

Sulfur can be processed into a variety of industrial and agricultural products such as sulfuric acid, fertilizers, explosives, pesticides, bactericides, paper, textile and rubber products, and the like. Sulphur may be derived from natural sulphur minerals, but also from by-products of coal processing, natural gas purification and petroleum refining, the sulphur as a by-product often being discharged in liquid form from the various process equipment described above. The liquid sulfur can be transported to each user by a heated tank car, but the transportation of the liquid sulfur is usually high in cost and inconvenient for long-distance transportation, so that most of the liquid sulfur is transported to each user after being solidified and formed into blocks or granules. Since sulfur is an explosive substance, any open fire or electrostatic friction may cause explosion when its dust concentration is high to some extent. The massive sulfur or granular sulfur products with high dust content produced by sulfur molding plants with laggard process technologies in the past cause sulfur dust environment and often explode in pelleting plants and user sites, thus harming the health and life of workers. Therefore, with the increasing environmental protection and safety awareness of the global working environment in recent years, the increasing technology of the sulphur molding granulation process is also required and promoted in order to produce sulphur granule products which are dust-free and are not easy to break and dust in transportation.

At present, there are three main sulphur forming granulation processes in the world, namely sulphur wet underwater granulation, dry steel belt granulation and dry roller granulation. The invention belongs to sulfur wet-process underwater granulation, which is called sulfur wet-process granulation for short.

The patent in the field of sulphur wet granulation is not numerous, and us 3334159 proposes a very simple sulphur wet granulation apparatus, comprising a liquid sulphur distributor with a plurality of holes at the bottom and keeping a constant liquid level, and a cooling water granulation vessel carrying granulation cooling water and keeping a cooling water level, wherein solidified sulphur particles fall to the bottom of the cooling water granulation vessel, the solidified particles are discharged out of the vessel by a water pump nozzle type suction device, the discharged sulphur particles are dehydrated and dried by a mechanical shaking screen and a wind blowing device, and the cooling water heated in the granulation process is recycled after heat exchange and cooling by a tubular heat exchanger. The process method and the simple equipment device for the wet granulation of the sulfur mainly have no requirements on parameters of the granulation process and equipment parameters, so that the product quality is extremely poor, a large amount of dust is generated, and the process method and the simple equipment device cannot be applied to the modern sulfur granulation industry.

U.S. patent 4149837 also proposes a similar sulphur wet granulation process, and proposes some ideas for improving granulation equipment and parameters of the granulation process. The temperature of the granulating cooling water is higher than 150 DEG F and is as close to the melting point temperature of sulfur as possible, a large amount of particle bonding can be generated under the process condition, the sulfur product required by any modern industry can not be produced, the method for discharging the solidified and formed sulfur particles out of the cooling water container is changed into the method for discharging the sulfur particles out of the container bottom by gravity and dehydrating the product by using a dehydrating screen arranged at the bottom of the granulating container, and the dehydrated product can be dried by hot air. It does not suggest any other process parameters and equipment parameters for wet granulation.

Us patent 4133669 proposes wet granulation of bentonite-containing liquid sulphur using the same apparatus as in us patent 4149837, the target granulated product being a sulphur granulate product containing bentonite. However, this granulation process has not been very successful in this application because the surface water of the granulated product causes the sulphur granules containing bentonite to slowly differentiate and break.

A recent patent in wet sulphur granulation would be the sequential us patents 7638076, 8011911 and 8277209B2 of the same inventor. This continuous patent mainly describes the details of their sulphur wet granulation process and equipment but is not an inventive part thereof. They are claimed to consist essentially of a cooler cooling water (55-60F) injection ring mounted below the overflow surface of a sulphur granulation vessel containing cooling water (95-105F), the injection ring being drilled with a plurality of outlet orifices, and cooling water at a temperature lower than the bulk cooling water temperature in the granulation vessel being injected through the injection ring from the outlet orifices into the upper part of the granulator, such that liquid sulphur just entering the cooling water contacts the injected cooling water (55-60F) at a temperature lower than the bulk cooling water temperature (95-105F) to promote solidification of the liquid sulphur as soon as it enters the water. However, the process has no application value in theory and practice, and can cause great increase of production cost and increase of internal stress of sulfur products, and the sulfur products are easy to break to generate fine grains and dust in subsequent dehydration, treatment and transportation. Heated liquid sulphur drip trays (i.e. liquid sulphur distributors) are also in their claims, but have long been used in the sulphur granulation industry before this patent.

As the global industry at present requires the reliable operation of the sulfur granulation process and the environment-friendly and safe working environment, especially in the western and Chinese, the produced sulfur particle products are required to be dust-free and safe in a granulation plant, and the sulfur dust is not generated as far as possible in the transportation process so as to ensure the safety, health and environment protection of product users. In order to meet the requirements, the sulfur granule product needs to have smooth granules, uniform granularity and low product moisture, and the condition of continuous granules in the product is reduced, so that higher requirements are put on a sulfur granulation process and a system.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a sulfur wet-process forming granulation production system, the produced sulfur solid particle product is spherical, has smooth surface and uniform granularity, does not contain any sulfur dust, is not easy to dust during bulk transportation and bagging transportation, has extremely low surface moisture content, and has far better sphericity, surface smoothness, granularity uniformity and surface moisture than the sulfur particle products produced by various sulfur granulation methods in the world at present; the invention also provides a production process thereof.

The invention relates to a sulphur wet-process forming granulation production system, which comprises a liquid sulphur filter, a liquid sulphur distributor, a granulation host, a product dehydration vibrating screen and a product conveying device which are sequentially arranged, wherein the upper end of the liquid sulphur distributor is also provided with an exhaust device, and the lower end of the product dehydration vibrating screen is also provided with a cooling water treatment integrated pool; the cooling water treatment integrated pool comprises a concentration pool, a water inlet pool, a sedimentation pool and a clean water pool which are sequentially arranged, wherein a fine grain spiral lifting device is arranged in the concentration pool, and a pH monitoring device is arranged in the clean water pool.

The liquid sulfur filter is arranged on a liquid sulfur conveying pipe connected with a heat preservation steam pipe, and the tail end of the liquid sulfur conveying pipe is arranged above the liquid flow distributor.

The liquid sulfur distributor comprises one or more liquid flow distributor units; the liquid flow distributor unit comprises a main distributor and a pre-distributor arranged in the main distributor, wherein a plurality of holes with the diameter of 10-15mm are distributed on the four sides of the bottom of the pre-distributor, a plurality of small holes with the diameter of 1-4mm are distributed on the bottom of the main distributor, and the distance between the centers of circles of the adjacent small holes is 6-30 mm; the small hole structure of the main distributor is in a shape of a cylinder at the upper part and an inverted circular truncated cone at the lower part.

Preferably, the distance between the centers of the adjacent small holes at the bottom of the main distributor is 8-25 mm.

The granulation main machine is provided with a water inlet, an overflow port, a discharge port and a glass window;

the water inlet is used for introducing process cooling water in the clean water tank into the granulation main machine through a water inlet pipe;

the overflow port leads part of the overflowing process cooling water into the clean water tank through an overflow pipe;

the discharge port is used for introducing solid sulfur particles and part of process cooling water into the product dehydration vibrating screen through a discharge pipe;

an image gray scale recognition camera is installed on the glass window, and the image gray scale recognition camera is connected with a pneumatic electric control valve and an alarm device which are installed on a material discharging pipe.

The distance from the bottom surface of the liquid sulfur distributor to the process cooling water overflow surface of the granulation main machine is 10-70 mm. Preferably 15-60 mm.

The product dehydration vibrating screen adopts a linear vibrating screen, and the part which is contacted with the sulfur particle product and the process cooling water adopts stainless steel 304, 316 or 316L material; the sulfur particle product is discharged to a product conveying device at the upper part of the product dehydration vibrating screen, and the process cooling water is discharged to a water tank at the bottom part of the product dehydration vibrating screen through a pipeline.

Introducing process cooling water into a concentration cyclone through a water inlet tank water pump, introducing a discharge port at the lower end of the concentration cyclone into a fine grain spiral lifting device of the concentration tank, and introducing the tail end of the fine grain spiral lifting device into a sulfur fine grain collecting container; the upper water outlet of the concentration cyclone is introduced into a sedimentation tank, supernatant of the sedimentation tank is introduced into a clean water tank through an overflow wall, the clean water tank introduces recovered cooling water into a heat exchanger through a clean water tank water pump, and the recovered cooling water is introduced into a granulation main machine after heat exchange; and a cold source medium of the heat exchanger is cooled through a cooling tower.

The production process of the wet-process sulfur forming and granulating production system comprises the following steps:

(1) removing solid impurities from the liquid sulfur by a liquid sulfur filter, generating uniformly distributed liquid sulfur lines from the liquid sulfur by a liquid flow distributor, introducing the liquid sulfur into a granulation host, generating sulfur liquid drops in process cooling water, and gradually cooling and solidifying the sulfur liquid drops into spherical solid sulfur particles; converting a sulfur material level image gray scale signal into an electric signal of 4-20mA by using an image gray scale identification camera through a glass window arranged on a granulation host, automatically adjusting a pneumatic electric control valve arranged on a discharge pipe at the bottom of the granulation host, thereby controlling the discharge flow of solid sulfur particles of the granulation host, simultaneously controlling an alarm device connected with the granulation host, and giving an alarm when the material level is higher than the highest material level or lower than the lowest material level;

(2) during granulation, discharging a part of process cooling water from an overflow port at the top of a main granulation machine, feeding the part of process cooling water into a clean water tank through an overflow pipe, discharging the rest of process cooling water and solid sulfur particles into a product dehydration vibrating screen for dehydration, conveying the dehydrated sulfur particle product to a product storage bin or a product packaging machine through a product conveying device, discharging the removed recovered cooling water into the water tank, introducing the process cooling water into a concentration cyclone through a water inlet tank water pump in the water tank, recovering sulfur fine particles in the process cooling water, discharging the sulfur fine particles into a fine particle spiral lifting device in the concentration tank through the bottom, lifting the sulfur fine particles from the concentration tank, dehydrating, lifting the sulfur fine particles to a machine head, discharging the sulfur fine particles into a sulfur fine particle collecting container, and performing short-time accumulation dehydration or further dehydration through a fine particle dehydration device to obtain a sulfur fine particle;

(3) introducing water obtained after sulfur fine particles are recovered from a concentration cyclone into a sedimentation tank for sedimentation, precipitating the ultrafine sulfur particles at the bottom, introducing supernatant into a clean water tank through an overflow wall, introducing process cooling water into a heat exchanger through a clean water tank water pump, introducing the process cooling water into a granulation host for reuse after heat exchange, wherein a cold source medium of the heat exchanger is cooled through a cooling tower, and the pH value of the cooling water in the clean water tank is controlled to be maintained within the range of 5.5-8.5 through a pH monitoring device.

The size of the filter pores of the liquid sulfur filter is 20-150 meshes.

The liquid sulfur level in the liquid sulfur distributor is 5-40mm, preferably 8-25 mm.

The product dehydration vibrating screen is a linear vibrating screen, the double amplitude is 6-15mm, the linear ejection angle is 30-60 degrees, and the excitation frequency is 700-.

As a preferred scheme, the production system and the production process for wet forming and granulating the sulfur are as follows:

(1) the liquid sulfur filter is used for removing impurities in the liquid sulfur and preventing the liquid sulfur from blocking the holes of the liquid sulfur pre-distributor and the main distributor. The liquid sulfur filter is arranged on the liquid sulfur conveying pipe and can also be arranged at any position where the liquid sulfur passes before entering the pre-distributor. The liquid sulfur filter is internally provided with a filter screen, the mesh size of the filter screen is 20-150 meshes, and after a certain amount of impurities are deposited in the filter screen, the filter screen needs to be cleaned in time when the machine is switched or stopped, or the filter screen needs to be cleaned. The material of the filter screen can be stainless steel or other materials which can resist high temperature and liquid sulfur corrosion.

(2) The exhaust device is used for filtering smoke and odor emitted when the liquid sulfur enters the liquid sulfur distributor and discharging the smoke and odor out of the granulating chamber, and the discharged exhaust gas meets the international gas emission standard. The exhaust device comprises an exhaust hood, an exhaust fan and a liquid sulfur smoke and odor filter. The odor filter may be of various filtering devices that filter out liquid sulfur fumes and pass odors, such as filters with activated carbon, and the like.

(3) The liquid sulfur distributor has the function of enabling liquid sulfur to generate liquid sulfur lines which are uniformly distributed and stably enter water to generate liquid drops, the liquid sulfur drops are uniformly distributed in process cooling water of the main granulation machine and are gradually cooled and solidified into spherical solid sulfur particles, and the solid sulfur particles are settled to the conical bottom of the main granulation machine and are continuously discharged out of the machine. The discharge speed of the solid sulfur particles is controlled by an electrically controlled pneumatic valve arranged on a discharge pipe of the granulation main machine. The solid sulfur particles discharged from the main granulation machine and part of process cooling water enter a product dehydration vibrating screen together, a sulfur particle product is obtained through dehydration, and the sulfur particle product is conveyed to a product storage bin or a product packaging machine through a belt conveyor or other conveying devices. As the surface of the spherical solid sulfur particles is smooth and very hydrophobic, the product is easy to dehydrate, and the water content of the product dehydrated by the product dehydration vibrating screen is 0.5-1.5wt percent and is never more than 2 percent. The sulfur pellet product exiting the product dewatering shaker may also enter the product hopper of the packaging system.

(4) The process cooling water of the granulation main machine is a cooling source of sulfur liquid drops, one part of the process cooling water after heat absorption is discharged into a clean water tank from an overflow port at the top of the main machine, and the rest part of the process cooling water enters a product dehydration vibrating screen from a discharge port along with solid sulfur particles and flows into a water inlet tank through a bottom funnel as the bottom flow of the product dehydration vibrating screen. The part of the recovered cooling water is pumped into a concentrating cyclone by a water pump in a water tank, the concentrating cyclone has the function of recovering sulfur fine particles in the recovered cooling water into the underflow of the concentrating cyclone and discharging the sulfur fine particles into a concentrating pool, and a screw elevator lifts and dehydrates the sulfur fine particles from the concentrating pool and lifts the sulfur fine particles to a head to be discharged into sulfur fine particle materials. The sulfur fine material can be discharged into a container with a filtering screen at the bottom and is dehydrated into a sulfur fine product after being accumulated for a short time, the product amount is about 0.05-0.1 percent of the total treatment amount of the sulfur wet granulation process, the sulfur fine product is sold as a single product or mixed into a main sulfur granular product or is introduced into a liquid sulfur pool to be melted and then is re-granulated, other fine dehydration devices can be used for further dehydrating the fine material, and the fine dehydration devices can be high-frequency vibration dehydration screens, various filters (such as various vacuum belt filters, gravity filters, roller filters and the like), filter presses and other filtering dehydration devices. The sulphur fines product further dewatered by any of these dewatering devices may be sold as a separate product or mixed into the main sulphur granule product or introduced into a liquid sulphur pool to be melted and re-granulated.

(5) The overflow of the concentration cyclone is discharged into a sedimentation tank, the function of the sedimentation tank is to make the extremely fine sulfur particles in the overflow (recovered cooling water) of the concentration cyclone precipitate at the bottom of the sedimentation tank, and the cooling water is discharged from the top of the sedimentation tank into a clean water tank through an overflow wall after being clarified in the sedimentation tank. And cooling water in the pool is cooled by a clean water pool water pump arranged in the clean water pool through a heat exchanger and then pumped back to the granulation main machine for recycling. The function of the heat exchanger is to use a cold source provided by the cooling tower to exchange heat absorbed by the process cooling water in the process of sulphur granulation. If the refinery or natural gas purification plant can provide the circulating cooling water, the cooling tower can be omitted and the circulating cooling water provided by the refinery or natural gas purification plant can be used instead of the circulating cooling water provided by the cooling tower.

(6) The circulating cooling water provided by the cooling tower is partially evaporated and lost in the process of operation, so that fresh cooling water is periodically replenished into the cooling tower in the production process by using a water level automatic control system on the cooling tower. The process cooling water in the clean water reservoir is also partially lost during the sulphur granulation process due to surface entrainment and natural evaporation of the sulphur granule product, so that fresh cooling water is automatically and periodically replenished into the clean water reservoir by controlling the level of the process cooling water in the clean water reservoir.

(7) In order to ensure the continuous and stable granulation production and the low moisture of the product, the granulation process adopts the invented image level control system to automatically control and maintain the material level of bed layer particles in the host machine, and uses a camera with image gray level identification function to convert the gray level signal of the sulfur particle material level image obtained from the window into an electric signal of 4-20mA through a glass window arranged on the granulation host machine, so as to control a pneumatic electric control valve arranged on a discharge pipeline at the bottom of the granulation host machine, thereby controlling the discharge flow of the sulfur particle product to maintain the stable sulfur particle material level in the host machine. The images of the closed circuit television arranged in the factory can monitor the sulfur particle material level at the same time. The image material level control system can also be provided with a high-level and low-level alarm material level, when the material level of particles in the granulator is suddenly increased to reach the high level or suddenly reduced to reach the low level, the alarm device is driven to alarm, the production is abnormal, a discharge port is possibly blocked or a discharge system (such as a discharge control valve and the like) is out of control, and the like, and a sensor signal can automatically cut off a liquid sulfur feeding pump or a liquid sulfur feeding valve at the same time of alarming to inform an operator of the reason caused by inspection. Another CCTV television monitoring point (not shown) will be located at the product dewatering screen outlet. If the bed position is suddenly increased, the blockage accident of the discharge port can also be reflected on the dewatering screen, and no product material is discharged from the dewatering screen.

(8) The pH value of the granulating cooling water in the wet granulation has certain influence on the product quality, and the control and maintenance of the pH value of the granulating cooling water are also very important in the wet granulation.

The liquid sulfur distributor and the granulation host machine are main units of a wet-process sulfur granulation process, and the structures and the sizes of the liquid sulfur distributor and the granulation host machine are designed according to the specific unit processing capacity and the invention for producing high-quality sulfur granule products.

The structural shape of the small holes of the main distributor has great influence on the quality of the sulfur particle products, the holes of the distributor generally adopt a cylindrical structure, liquid sulfur can diffuse towards the bottom edge of the holes of the distributor when passing through the holes and flows to other holes along the bottom surface, and the produced sulfur particle products have more grain connection phenomena; the small hole of the main distributor is designed into a structure with the upper part cylindrical and the lower part inverted truncated cone, liquid sulfur cannot diffuse towards the edge of the bottom of the distributor hole and flow to other holes along the bottom surface when passing through the small hole, interference between adjacent liquid sulfur bundles is reduced, the edge of the generated liquid sulfur bundle is cleaner, and therefore the produced sulfur particle product has more single particles and fewer continuous particles.

In addition, through high-speed camera observation, the liquid sulfur distributor generates liquid sulfur beams, and the liquid sulfur beams enter process cooling water and automatically form spherical liquid drops due to high hydrophobicity of the surface of sulfur so as to be solidified into spherical sulfur particle products. The diameter of the small hole of the main distributor can be 1-4mm according to the size of the sulfur particle product to be produced. Too small a mesh diameter results in too small a particle produced, too small a granulation throughput and easy clogging of the mesh; too large an aperture may result in too large sulphur pellets being produced, sulphur droplets being prone to coalescence and sulphur pellet product being prone to breakage to produce sulphur dust. The circle center distance of the adjacent small holes has great influence on the quality of the sulfur granule product, and the distance is preferably 6-30mm, and most preferably 8-25 mm; too small a distance produces too many continuous sulfur pellet products, too poor an appearance, large fines content, brittle product pellets, and too high a product moisture; too large a distance results in too small a throughput of the pelletizing system.

The liquid sulfur level of the liquid sulfur distributor can also seriously affect the quality of the granulated product, and the liquid sulfur level S can be set to be 5-40mm, preferably 8-30mm according to the requirements of the granulation yield and the quality of the granulated product. Too low a liquid sulphur level reduces the processing capacity of the granulation and deteriorates the quality of the product; too high a liquid sulphur level may effectively increase the granulation process capacity but may deteriorate the quality of the granulated granules.

The process cooling water liquid level of the granulation main machine must keep a constant cooling water overflow liquid level. The distance between the liquid sulfur distributor and the cooling water overflow liquid level of the granulation main machine has great influence on the quality of the sulfur wet granulation product, and the qualified sulfur granule product cannot be manufactured by too large and too small distance. In order to ensure that the sulphur wet granulation process system produces high-quality sulphur granule products, the distance from the bottom surface of the liquid sulphur distributor to the cooling water overflow surface of the granulation main machine is set within the range of 10-70mm, and preferably set within the range of 15-60 mm.

The water supply amount and temperature of the cooling water of the granulator process must be reasonably matched and set, and the principle is to reduce the water supply amount of the cooling water as much as possible on the premise of ensuring the product quality and the water temperature of the cooling water so as to reduce the power consumption. The flow rate of the process cooling water can be adjusted by using a process water supply pump and matching a frequency converter, and the supply amount of the cooling water can be adjusted by adjusting the frequency of the frequency converter.

The invention also improves the sulfur solid particle discharge and control mode of the granulation main machine.

The product discharge process provided by the invention adopts an underflow large discharge method without product material level in the granulation host machine, and the discharge method has the advantages that the possibility of blockage of a discharge pipe at the bottom of the granulation host machine can be reduced, and an automatic control system of the material level is not required; but a large amount of process cooling water can be discharged at the same time, the load of the product dehydration vibrating screen is increased, and the consumption of the process cooling water is also increased.

The other product discharging process provided by the invention adopts a discharging method for maintaining a certain product material level in the main machine, and realizes the product material level monitoring in the granulation main machine and the control of the product discharging flow rate through an image material level automatic control system. The conventional discharging process is manually controlled, and the discharging method has the advantages that a discharging valve at the bottom is not required to be manually controlled, the discharging speed of the granular product is very uniform and stable, the water content of the product is reduced, and the quality of the product is improved; the maximum content of the granular materials in the discharged materials is low, so that the amount of cooling water discharged to the product dehydration vibrating screen can be greatly reduced, the load of the product dehydration vibrating screen is reduced, and the dehydration efficiency of the product dehydration vibrating screen is effectively improved; because the bottom water discharge is reduced, the injection amount of the process cooling water is also reduced, the power consumption of the water pump is reduced, and the granulation cost is reduced.

The invention adopts the linear vibrating screen as the product dewatering vibrating screen, and the process parameters are limited as key technologies. All previous inventions of sulphur wet granulation process and system equipment neglect the technical parameter which has the greatest influence on the moisture of sulphur wet granulation granule products. Dewatering screens are mostly mentioned in the past sulphur wet granulation inventions, but the dewatering screens and the vibrating screen used in the prior art can not effectively remove the water of sulphur wet granulation products, and can not meet the requirements of Chinese national standard (the water of sulphur products is less than or equal to 2%). The moisture of the sulfur granule product is one of the most important product quality indexes of the sulfur granule product internationally, and the moisture is the only index for measuring the quality of the sulfur granule product in China. A large number of tests prove that the linear vibrating screen can effectively reduce the moisture of the sulfur wet granulation product to 0.5-1.5 percent under the process parameters of 6-15mm of double amplitude, 30-60 degrees of linear ejection angle and 1000 times/minute of excitation frequency of 700-.

Compared with the prior art, the invention has the following beneficial effects:

(1) the sulfur solid particle product produced by the invention is spherical, has smooth surface and uniform granularity, does not contain any sulfur dust, is not easy to dust during bulk transportation and bagging transportation, and has extremely low surface moisture content, the dominant particle size fraction of 2.4-4.8mm in the sulfur particle product accounts for more than 92 percent of the total particle product, and the moisture content is 0.5-1.5 percent, which are all superior to the sulfur particle product produced by the existing sulfur wet granulation process;

(2) the liquid sulfur distributor adopts a two-stage distribution structure, so that the liquid sulfur beams are distributed more uniformly, small holes of the main distributor are designed into an upper cylindrical structure with an inverted truncated cone shape at the lower part, liquid sulfur cannot diffuse towards the edges of the bottoms of the holes of the distributor and flows along the bottom surface to other holes when passing through the small holes, the interference between adjacent liquid sulfur beams is reduced, the edges of the generated liquid sulfur beams are cleaner, and the produced sulfur particle products have more single particles and less continuous particles;

(3) according to the invention, the diameter sizes and adjacent sizes of the holes and the small holes of the liquid flow distributor are designed, so that sulfur liquid drops are not easy to merge, the holes are also ensured not to be blocked, the surface of the produced sulfur particle product is smooth, and sulfur dust is not contained;

(4) the granulating host machine improves the discharging and controlling mode of the sulfur solid particles, realizes the product material level monitoring and the product discharging flow control in the granulating host machine through the image material level automatic control system, does not need to manually control a discharging valve at the bottom, simultaneously ensures that the discharging speed of the particle products is very uniform and stable, reduces the water content of the products and improves the quality of the products; the maximum content of the granular materials in the discharged materials is low, so that the amount of cooling water discharged to the product dehydration vibrating screen can be greatly reduced, the load of the product dehydration vibrating screen is reduced, and the dehydration efficiency of the product dehydration vibrating screen is effectively improved; because the bottom drainage is reduced, the injection amount of process cooling water is also reduced, the power consumption of a water pump is reduced, and the granulation cost is reduced;

(5) the invention adopts the linear vibrating screen as the product dehydration vibrating screen, sets the technological parameters of the linear vibrating screen as double amplitude of 6-15mm, linear ejection angle of 30-60 degrees and excitation frequency of 700 times/minute, can effectively reduce the moisture of the sulfur wet granulation product to 0.5-1.5 percent, which is greatly lower than the requirement of China standard for the moisture of the sulfur product to be less than or equal to 2 percent.

Drawings

FIG. 1 is a schematic diagram of a sulphur wet-forming granulation production system according to the present invention;

FIG. 2 is a schematic view showing the structure of a liquid flow distribution unit of the liquid sulfur distributor according to the present invention;

FIG. 3 is a schematic structural view of a liquid sulfur distributor comprising four liquid flow distribution units according to the present invention;

FIG. 4 is a schematic longitudinal cross-sectional view of the cell structure of the flow distribution unit of the present invention;

in the figure: 1. a heat preservation steam pipe; 2. a liquid sulfur filter; 3. a liquid sulfur delivery pipe; 4. an exhaust device; 5; a liquid flow distributor; 6. an overflow port; 7. a granulation host machine; 8. a water inlet; 9. a glass window; 10. an alarm device; 11. an image gray scale recognition camera; 12. a discharge outlet; 13. a pneumatic electric control valve; 14. a product dehydration vibrating screen; 15. a product delivery device; 16. a concentrating cyclone; 17. a sulfur fines collection vessel; 18. a concentration tank; 19. a fines spiral lifting device; 20. a water pump entering the water tank; 21. entering a water pool; 22. a sedimentation tank; 23. a clean water tank; 24. a clean water tank water pump; 25. a cooling water treatment integrated pool; 26. a pH monitoring device; 27. a heat exchanger; 28. a cooling tower; 29. a liquid flow distributor unit; 30. a main distributor; 31. a small eyelet; 32. an eyelet; 33. a pre-distributor.

Detailed Description

The present invention is further illustrated by the following examples, but the scope of the present invention is not limited thereto, and modifications of the technical solutions of the present invention by those skilled in the art should be within the scope of the present invention.