Phosphogypsum recycling system

Abstract

The utility model provides an ardealite recycling system. The ardealite recycling system comprises a pickling tank, a clarifying tower and a reacting furnace, the pickling tank is provided with a raw material inlet and a washing liquid outlet; the clarifying tower is provided with a washing liquid feeding hole, a pickling slurry discharging hole and a pickling clear liquid discharging hole; the reaction furnace is provided with a crude product feed port, a fuel feed port, an acid gas discharge port and a product discharge port; the washing liquid discharge port is connected with the washing liquid feed port through a washing liquid pipeline, and the pickling slurry discharge port is connected with the crude product feed port. According to the device, a large amount of calcium oxide with a wide application range is generated while the waste residues are cleaned and treated, meanwhile, tail gas is ensured to meet the environmental protection standard and be discharged, sulfuric acid and steam are produced as byproducts, the waste residue phosphogypsum is properly treated, and meanwhile, certain economic value is generated.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of phosphogypsum recycling system. BACKGROUND

[0002] Phosphogypsum is an industrial waste residue generated in the production process of phosphate fertilizer, and its main component is calcium sulfate dihydrate (CaSO4·2H2O). Wet production of 1 ton of phosphoric acid (P2O5) emits about 5 tons of phosphogypsum. The world's annual phosphogypsum emissions are about 200 million tons, and China's annual emissions have exceeded 20 million tons, with a stockpile of more than 300 million tons, a utilization rate of only 30%. In addition to occupying a large amount of land, phosphogypsum stockpiling also causes dust, groundwater and soil pollution and other environmental problems.

[0003] With the continuous expansion of the scale of domestic and foreign wet-process phosphoric acid processing industry, the comprehensive utilization of phosphogypsum has become a common problem for the sustainable development of the industry. The main way of comprehensive utilization of phosphogypsum in China is to replace natural gypsum to produce cement retarder, prepare building materials, prepare soil conditioner, and co-produce cement with acid.

[0004] Although these methods have been applied in industry, they are not enough to solve the comprehensive utilization of phosphogypsum. For example, although the production of cement retarder is effective, it is limited by the scale of cement production and the number of manufacturers that replace natural gypsum with phosphogypsum. The preparation of building materials from phosphogypsum is also limited due to the influence of impurities on the performance of building materials. Phosphogypsum can be used to prepare soil conditioner for saline-alkali land and soil structure improvement, but there is still a long way to go in actual promotion. The co-production of cement with acid from phosphogypsum is still in its infancy, and the raw material configuration requires high-precision instruments and equipment. The operation control of the rotary kiln is difficult due to the narrow decomposition range of gypsum and the many side reactions, so the technology and operation of co-production of cement with acid from phosphogypsum still need to be innovated and improved. SUMMARY

[0005] The technical problem to be solved by the utility model is to overcome the defects of the prior art and provide a phosphogypsum recycling system.

[0006] The utility model solves the above technical problems by the following technical solutions:

[0007] The utility model provides a kind of phosphogypsum recycling system, it includes pickling tank, clarifying tower and reaction furnace;

[0008] The pickling tank is provided with a raw material inlet and a washing liquid outlet;The clarifying tower is provided with a washing liquid inlet, an acid washing slurry outlet and an acid washing clear liquid outlet;The reaction furnace is provided with a crude product inlet, a fuel inlet, an acid gas outlet and a product outlet;

[0009] The washing liquid outlet is connected with the washing liquid inlet through a washing liquid pipeline, and the pickling slurry outlet is connected with the crude product inlet;

[0010] The pickling clear liquid outlet is also connected with a pickling clear liquid treatment unit, and the pickling clear liquid treatment unit comprises a pickling clear liquid collecting tank provided with a clear liquid inlet, a treatment agent inlet and a treatment slurry outlet; the clear liquid outlet is connected with the clear liquid inlet;

[0011] The pickling clear liquid treatment unit further comprises a treatment slurry filter, and the treatment slurry filter comprises a treatment slurry inlet, a backflow filtrate outlet and a treatment filter cake outlet; the treatment slurry inlet is connected with the treatment slurry outlet through a treatment slurry pipeline.

[0012] In the utility model, the main component of phosphogypsum is dihydrate gypsum (CaSO4·2H2O), and in addition to the main component calcium sulfate, phosphogypsum also contains a small amount of phosphoric acid, silicon, fluorine, magnesium, iron, aluminum, organic impurities and the like, and the existence of these impurities causes great disturbance to the reuse of phosphogypsum, and these impurities are removed (dissolved in dilute acid) before the calcination section, so as to reduce the influence of impurities on the subsequent products CaO and acid gas. - In the solution, the solution cannot be discharged, so CaO is added in the liquid to make F - Exist in the form of CaF2, so as to collect and store.

[0013] In the utility model, the pickling tank can be provided with a stirring device.

[0014] In the utility model, a washing liquid pump can be arranged on the washing liquid pipeline.

[0015] In the utility model, the raw material inlet can comprise a phosphogypsum inlet and a dilute acid inlet.

[0016] In the utility model, a treatment slurry pump can be arranged on the treatment slurry pipeline. The pickling tank can also be provided with a filtrate backflow port, and the backflow filtrate outlet is connected with the filtrate backflow port through a backflow filtrate pipeline. A backflow filtrate pump can be arranged on the backflow filtrate pipeline. The treatment slurry filter can be a plate and frame filter.

[0017] In the utility model, according to the conventional, the height of the pickling slurry outlet is lower than the height of the pickling clear liquid outlet.

[0018] The utility model discloses a pickling slurry discharge port and the rough product feed port between still can be equipped with pickling slurry processing unit, pickling slurry processing unit includes pickling slurry filter and dryer, pickling slurry filter is equipped with pickling slurry feed port, pickling filtrate discharge port and pickling filter cake discharge port, the dryer is equipped with pickling filter cake feed port, rough product discharge port and tail gas outlet, pickling slurry feed port with pickling slurry discharge port connects, pickling filter cake discharge port with pickling filter cake feed port connects, rough product discharge port with rough product feed port connects.

[0019] Among them, the pickling slurry processing unit can further include a dryer dust collector, the dryer dust collector is equipped with a tail gas inlet, a second tail gas outlet and a second rough product discharge port, the tail gas inlet is connected with the tail gas outlet, and the second rough product discharge port is connected with the rough product feed port. The second tail gas outlet can be connected with the air inlet of the drying induced draft fan. The pickling slurry processing unit can further include a conveyor, the rough product discharge port is connected with the feed end of the conveyor, and the discharge end of the conveyor is connected with the rough product feed port. The dryer can be a drum dryer. The rotary drum of the drum dryer can be slightly inclined and can rotate. The rotary drum of the drum dryer can be provided with a forward direction scoop plate. The conveyor can include a belt conveyor and a bucket elevator connected in sequence. A pulverizer can be arranged between the discharge end of the conveyor and the rough product feed port. The pulverizer can be a vibration pulverizer. The pickling slurry filter can be a plate and frame filter.

[0020] In a specific embodiment of the utility model, the pickling slurry discharge port and the rough product feed port between still can be equipped with pickling slurry processing unit, pickling slurry processing unit includes pickling slurry filter, dryer, dryer dust collector, belt conveyor, bucket elevator and pulverizer;

[0021] The pickling slurry filter is equipped with a pickling slurry feed port, a pickling filtrate discharge port and a pickling filter cake discharge port; the dryer is equipped with a pickling filter cake feed port, a rough product discharge port and a tail gas outlet; the dryer dust collector is equipped with a tail gas inlet, a second tail gas outlet and a second rough product discharge port;

[0022] The pickling slurry feed port is connected with the pickling slurry discharge port, the pickling filtrate discharge port is connected with the clear liquid feed port through a clear liquid pipeline, a clear liquid pump is arranged on the clear liquid pipeline, the pickling filter cake discharge port is connected with the pickling filter cake feed port, the coarse product discharge port and the second coarse product discharge port are connected with the feeding end of the belt conveyor, the discharging end of the belt conveyor is connected with the feeding end of the bucket elevator, the discharging end of the bucket elevator is connected with the feeding end of the crusher, the discharging end of the crusher is connected with the coarse product feed port, the tail gas air inlet is connected with the tail gas air outlet, and the second tail gas air outlet is connected with the air inlet of the drying induced draft fan.

[0023] In the utility model, the acid gas discharge port and the product discharge port can be connected with a product processing unit, the product processing unit comprises an acid gas dust remover and a bin, the acid gas dust remover is equipped with an acid gas feed port, a second acid gas discharge port and a second product discharge port, the acid gas feed port is connected with the acid gas discharge port, and the second product discharge port and the product discharge port are connected with the feed port of the bin.

[0024] In the utility model, the reaction furnace can be a cross-shaped reaction furnace. The fuel feed port can be provided with two, and is located at the two sides of the reaction furnace respectively. The acid gas discharge port can be located at the top of the reaction furnace. The product discharge port can be located at the bottom of the reaction furnace.

[0025] In the utility model, the hearth of the reaction furnace can be made of refractory bricks.

[0026] The positive progress effect of the utility model is that:

[0027] (1) In the utility model, phosphogypsum is comprehensively utilized, the process is simpler, and the operability is stronger, and the process can be popularized in the industrial field, not only can the sulfur, calcium and other resources in the phosphogypsum be fully recycled, but also can the whole process be ensured to be free of waste water, waste residue and waste gas pollution, the problems of phosphogypsum storage, land occupation and pollution are solved, the problem of sulfur resource shortage in China is alleviated, waste is turned into treasure to realize sustainable development of resources, and the problems of industrial waste residue safe incineration, environmental protection standard reaching, energy saving and emission reduction are realized, the tail gas meets the environmental protection standard reaching emission, and sulfuric acid and steam are by-produced, not only the waste residue phosphogypsum is properly treated, but also certain economic value is generated.

[0028] (2) In the utility model, the operation is simple, the energy consumption is small, the operation is simple, the treatment cost is low, the environmental protection benefit is obvious, other harmful substances are not generated during the clean treatment of the waste residue, the product calcium oxide and the SO2-containing gas acidification have good economic benefits, and the purpose of safe incineration of industrial waste residue, environmental protection standard reaching, energy saving and emission reduction is finally realized, the tail gas meets the environmental protection standard reaching emission, and sulfuric acid and steam are by-produced, not only the waste residue phosphogypsum is properly treated, but also certain economic value is generated. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A phosphogypsum recycling system schematic diagram of Example 1;

[0030] Figure 2 A phosphogypsum recycling system schematic diagram of Example 2;

[0031] The figure shows: pickling tank V-101, pickling clear liquid collecting tank V-102, silo V-103, clarifying tower T-101, reaction furnace R-101, washing liquid pump P-101, clear liquid pump P-102, treatment slurry pump P-103, backflow filtrate pump P-104, pickling slurry filter F-101, treatment slurry filter F-102, dryer D-101, dryer dust collector X-101, pulverizer X-102, acid gas dust collector X-103, product pulverizer X-104, drying induced draft fan C-101, belt conveyor L-101, bucket elevator L-102. DETAILED DESCRIPTION

[0032] The preferred embodiments are described below in conjunction with the accompanying drawings, which more fully and completely illustrate the present application.

[0033] Example 1

[0034] A phosphogypsum recycling system, such as Figure 1 , includes pickling tank V-101, clarifying tower T-101 and reaction furnace R-101; pickling tank V-101 is provided with raw material feeding port, washing liquid discharge port and filtrate backflow port; clarifying tower T-101 is provided with washing liquid feeding port, pickling slurry discharge port and pickling clear liquid discharge port; reaction furnace R-101 is provided with coarse product feeding port, fuel feeding port, acid gas discharge port and product discharge port; washing liquid discharge port is connected with washing liquid feeding port through washing liquid pipeline.

[0035] In this embodiment, the raw material feeding port includes phosphogypsum feeding port and dilute acid feeding port. In this embodiment, pickling tank V-101 is provided with stirring device. In this embodiment, the height of pickling slurry discharge port is lower than that of pickling clear liquid discharge port. In the present application, reaction furnace R-101 is cross-shaped reaction furnace, fuel feeding port is provided with two, which are located at both sides of reaction furnace R-101, acid gas discharge port can be located at the top of reaction furnace R-101, and product discharge port can be located at the bottom of reaction furnace R-101. In the present application, the hearth of reaction furnace R-101 is built by refractory bricks.

[0036] In the embodiment, the clean liquid outlet is also connected with the pickling clean liquid treatment unit, and the pickling clean liquid treatment unit comprises a pickling clean liquid collecting tank V-102 and a treatment slurry filter F-102. The pickling clean liquid collecting tank V-102 is provided with a clean liquid inlet, a treatment agent inlet and a treatment slurry outlet. The treatment slurry filter F-102 comprises a treatment slurry inlet, a backflow filtrate outlet and a treatment filter cake outlet. The clean liquid outlet is connected with the clean liquid inlet. The treatment slurry inlet is connected with the treatment slurry outlet through a treatment slurry pipeline. The backflow filtrate outlet is connected with the filtrate backflow port through a backflow filtrate pipeline. In the embodiment, the treatment slurry filter F-102 is a plate and frame filter.

[0037] In the embodiment, the pickling slurry outlet and the crude product inlet are also provided with a pickling slurry treatment unit. The pickling slurry treatment unit comprises a pickling slurry filter F-101 and a dryer D-101. The pickling slurry filter F-101 is provided with a pickling slurry inlet, a pickling filtrate outlet and a pickling filter cake outlet. The dryer D-101 is provided with a pickling filter cake inlet, a crude product outlet and an exhaust air outlet. The pickling slurry inlet is connected with the pickling slurry outlet. The pickling filter cake outlet is connected with the pickling filter cake inlet. The crude product outlet is connected with the crude product inlet. The pickling filtrate outlet is connected with the clean liquid inlet. In the embodiment, the dryer D-101 is a drum dryer.

[0038] In the embodiment, waste residue phosphogypsum generated in the production process of phosphate fertilizer is recycled to generate products such as calcium oxide and SO2-containing acid gas. The following four treatment processes are involved:

[0039] 1. Dilute sulfuric acid hydrolysis of phosphogypsum: The phosphogypsum entering from the phosphogypsum inlet mainly contains dihydrate gypsum (CaSO4·2H2O) and a small amount of phosphoric acid, silicon, fluorine, magnesium, iron, aluminum, organic impurities and the like. Fe 3+ , Al 3+ , F - , Na + , K +The metal ions are stirred in the acid washing tank V-101 to make the dissolution more sufficient and remove the impurities more effectively, which helps to generate calcium oxide with higher purity, wherein most of the impurity ions are dissolved in the dilute sulfuric acid entering from the dilute acid inlet, the concentration of the dilute sulfuric acid is 25wt%-30wt%, the mass ratio of the phosphogypsum to the dilute sulfuric acid is 1: (1.5-3), the phosphogypsum is treated by acid washing, and the pH is controlled between 5-6. The dilute acid removes about 95%-98% of phosphorus, the removal rate of silicon is 50%-60%, the removal rate of iron is 50%-60%, the removal rate of fluorine is 70%-80%, and the removal rate of potassium is 65%-75%. After the acid washing of the phosphogypsum, a small part of impurity elements such as silicon, fluorine, aluminum, and iron still remains. The washing liquid formed by the acid washing of the phosphogypsum is introduced into the clarifying tower T-101, and the washing liquid is a liquid-solid mixture, which is separated into two layers in the clarifying tower T-101, i.e. a lower slurry layer and an upper clear liquid layer. The operation of the clarifying tower T-101 is at normal temperature and the pressure is about 0.3 MPaG.

[0040] 2. Solid filtration, drying and crushing: the acid washing slurry in the lower layer of the clarifying tower T-101 is introduced into the acid washing slurry filter F-101 for filtration, the filtered acid washing clear liquid is introduced into the acid washing clear liquid collecting tank V-102, and the filtered acid washing filter cake is introduced into the drying machine D-101 for drying at a temperature of 150-160°C to obtain a crude product, and the tail gas generated is sent to the acid tail washing tower.

[0041] 3. Calcination: the crude product is introduced into the reaction furnace R-101 to react with the coal gas introduced from the fuel inlet, which requires high temperature to make the reaction fully proceed and reduce the occurrence of side reactions. The reaction furnace R-101 is at normal pressure, and the reaction temperature is 1350-1450°C. The reaction mainly occurs as follows:

[0042]

[0043]

[0044] After the above series of procedures, the main component CaSO4 in the phosphogypsum reacts with the coal gas to generate solid CaO flowing to the product outlet. Due to the reaction in excess of the coal gas, the calcination after the reaction not only obtains CaO and SO2, but also generates CO2 and CO as by-products, which can be used as synthesis gas to the wet-process sulfuric acid device.

[0045] 4. Deep treatment of waste liquid: the acid washing clear liquid in the upper layer of the clarifying tower T-101 and the acid washing clear liquid filtered by the acid washing slurry filter F-101 are introduced into the acid washing clear liquid collecting tank V-102, CaO is added from the treatment agent inlet, and a CaF2 precipitate is generated by the reaction. The reaction mainly occurs as follows:

[0046]

[0047] The obtained treatment slurry is filtered through a treatment slurry filter F-102, and the obtained backflow filtrate is introduced into the acid washing tank V-101 for washing and recycling, and the obtained CaF2 solid is collected and stored.

[0048] Example 2

[0049] A phosphogypsum recycling system, such as Figure 2 , comprises an acid washing tank V-101, a clarification tower T-101, and a reaction furnace R-101; the acid washing tank V-101 is provided with a raw material inlet, a washing liquid outlet, and a filtrate backflow port; the clarification tower T-101 is provided with a washing liquid inlet, an acid washing slurry outlet, and an acid washing clear liquid outlet; the reaction furnace R-101 is provided with a crude product inlet, a fuel inlet, an acid gas outlet, and a product outlet; the washing liquid outlet is connected to the washing liquid inlet through a washing liquid pipeline.

[0050] In this embodiment, the acid washing tank V-101 is provided with a stirring device. In this embodiment, a washing liquid pump P-101 is arranged on the washing liquid pipeline. In this embodiment, the raw material inlet comprises a phosphogypsum inlet and a dilute acid inlet. In this embodiment, the height of the acid washing slurry outlet is lower than the height of the acid washing clear liquid outlet. In this embodiment, the reaction furnace R-101 is a cross-shaped reaction furnace, the fuel inlet is provided with two inlets respectively located on both sides of the reaction furnace R-101, the acid gas outlet can be located at the top of the reaction furnace R-101, and the product outlet can be located at the bottom of the reaction furnace R-101.

[0051] In this embodiment, the acid washing clear liquid outlet is further connected to an acid washing clear liquid treatment unit, and the acid washing clear liquid treatment unit comprises an acid washing clear liquid collection tank V-102 and a treatment slurry filter F-102; the acid washing clear liquid collection tank V-102 is provided with a clear liquid inlet, a treatment agent inlet, and a treatment slurry outlet; the treatment slurry filter F-102 comprises a treatment slurry inlet, a backflow filtrate outlet, and a treatment filter cake outlet; the clear liquid outlet is connected to the clear liquid inlet, the treatment slurry inlet is connected to the treatment slurry outlet through a treatment slurry pipeline, a treatment slurry pump P-103 is arranged on the treatment slurry pipeline, the backflow filtrate outlet is connected to the filtrate backflow port through a backflow filtrate pipeline, and a backflow filtrate pump P-104 is arranged on the backflow filtrate pipeline.

[0052] In the embodiment, the pickling slurry outlet and the crude product inlet are further provided with a pickling slurry treatment unit, the pickling slurry treatment unit comprising a pickling slurry filter F-101, a dryer D-101, a dryer dust collector X-101, a belt conveyor L-101, a bucket elevator L-102 and a crusher X-102; the pickling slurry filter F-101 is provided with a pickling slurry inlet, a pickling filtrate outlet and a pickling filter cake outlet; the dryer D-101 is provided with a pickling filter cake inlet, a crude product outlet and a tail gas outlet; the dryer dust collector X-101 is provided with a tail gas inlet, a second tail gas outlet and a second crude product outlet; the pickling slurry inlet is connected with the pickling slurry outlet, the pickling filtrate outlet is connected with the clear liquid inlet through a clear liquid pipeline, the clear liquid pipeline is provided with a clear liquid pump P-102, the pickling filter cake outlet is connected with the pickling filter cake inlet, the crude product outlet and the second crude product outlet are connected with the feeding end of the belt conveyor L-101, the discharging end of the belt conveyor L-101 is connected with the feeding end of the bucket elevator L-102, the discharging end of the bucket elevator L-102 is connected with the feeding end of the crusher X-102, the discharging end of the crusher X-102 is connected with the crude product inlet, the tail gas inlet is connected with the tail gas outlet, and the second tail gas outlet is connected with the air inlet of the drying induced draft fan C-101. In the embodiment, the pickling slurry filter F-101 is a plate and frame filter. In the embodiment, the crusher X-102 is a vibration crusher.

[0053] In the embodiment, the dryer D-101 is a roller dryer, the roller of the roller dryer is slightly inclined and can rotate, the height of the pickling filter cake inlet is higher than the height of the crude product outlet, and the roller of the roller dryer is provided with a forward lifter, so that the material is continuously lifted and then poured in the process of the rotation of the cylinder, so that the material is fully contacted with the hot air flow to improve the drying efficiency and move the material forward.

[0054] In the embodiment, the acid gas outlet and the product outlet are further connected with a product treatment unit, the product treatment unit comprising an acid gas dust collector X-103 and a bin V-103, the acid gas dust collector X-103 being provided with an acid gas inlet, a second acid gas outlet and a second product outlet, the acid gas inlet being connected with the acid gas outlet, the second product outlet and the product outlet being connected with the feeding inlet of the bin V-103, and the discharging outlet of the bin V-103 being further connected with the feeding inlet of a product crusher X-104.

[0055] In the embodiment, the main components of the phosphogypsum are as follows: CaSO4·2H2O about 86.7wt%, SiO2 about 8.8wt%, Ca3P2O8 about 2.4wt%, trace amounts of MgO, CaF2 and Fe2(SO4)3, and the total amount of the phosphogypsum is 2026 kg / h, and the treatment process is as follows:

[0056] The phosphogypsum from the raw material inlet and 30wt% dilute sulfuric acid from the dilute acid inlet are dissolved in the pickling tank V-101 with a mass ratio of 1:2 while stirring, generating a variety of sulfate solutions and a precipitate mixture, and the obtained solid-liquid mixture is pumped into the clarifying tower T-101 by the washing liquid pump P-101 and is settled into two layers, a lower slurry layer and an upper clear liquid layer, in the clarifying tower T-101. The operating temperature of the clarifying tower T-101 is normal temperature, and the operating pressure is 0.3 MPaG.

[0057] The pickling slurry in the lower layer of the clarifying tower T-101 is filtered in the pickling slurry filter F-101, and the filtered pickling clear liquid is pumped into the pickling clear liquid collection tank V-102 by the clear liquid pump P-102, CaO is added from the treatment agent inlet, a reaction occurs to generate CaF2 precipitate, so that the pickling clear liquid collection tank V-102 forms a treatment slurry, which is a solid-liquid mixed slurry, the treatment slurry is pumped into the treatment slurry filter F-102 by the treatment slurry pump P-103, and the obtained backflow filtrate after filtration is pumped into the pickling tank V-101 by the backflow filtrate pump P-104 for washing and recycling, and the obtained CaF2 solid is collected and stored.

[0058] The pickling filter cake after the pickling slurry filter F-101, that is, the CaSO4 solid containing a certain amount of water, is first dried in the drying machine D-101 at a drying temperature of 160°C, and then dusted in the drying machine dust collector X-101, the small volume solid deposited and the solid after the drying machine D-101 drying are transported together by the belt conveyor L-101 and the bucket elevator L-102 to the pulverizer X-102 for pulverization, and the pulverized coarse product is 10 μm < D90 < 90 μm. The tail gas generated by the drying machine dust collector X-101 is sent to the acid tail washing tower.

[0059] The coarse product enters the reaction furnace R-101, and excess coal gas is introduced from the fuel inlet, at 1350°C, the CaSO4 solid reacts with CO and H2 in the coal gas to generate CaO solid and SO2, CO2 gas. After recooling, the SO2, CO2 gas and excess coal gas are sent to the acid gas dust collector X-103 for dust removal, and then can enter the subsequent acid making unit. The CaO solid generated by the reaction furnace R-101 is discharged from the product discharge port into the silo V-103, together with the small particle CaO solid falling after the acid gas dust collector X-103 dust removal, and is packaged and shipped out after being pulverized to the required size by the product pulverizer X-104.

Claims

1. A phosphogypsum recycling system, characterized by, It includes acid washing tank (V-101), clarification tower (T-101) and reaction furnace (R-101); The acid washing tank (V-101) is provided with raw material feeding port and washing liquid outlet; the clarification tower (T-101) is provided with washing liquid feeding port, acid washing slurry outlet and acid washing clear liquid outlet; the reaction furnace (R-101) is provided with crude product feeding port, fuel feeding port, acid gas outlet and product outlet; The washing liquid outlet is connected with the washing liquid feeding port through washing liquid pipeline, and the acid washing slurry outlet is connected with the crude product feeding port; The acid washing clear liquid outlet is also connected with acid washing clear liquid treatment unit, and the acid washing clear liquid treatment unit comprises acid washing clear liquid collecting tank (V-102), which is provided with clear liquid feeding port, treatment agent feeding port and treatment slurry outlet; the clear liquid outlet is connected with the clear liquid feeding port; The acid washing clear liquid treatment unit further comprises treatment slurry filter (F-102), which comprises treatment slurry feeding port, backflow filtrate outlet and treatment filter cake outlet; the treatment slurry feeding port is connected with the treatment slurry outlet through treatment slurry pipeline; the treatment slurry pipeline is provided with treatment slurry pump (P-103); The acid washing tank (V-101) is also provided with filtrate backflow port, and the backflow filtrate outlet is connected with the filtrate backflow port through backflow filtrate pipeline.

2. The phosphogypsum recycling system of claim 1, wherein, The acid washing tank (V-101) is provided with stirring device; the washing liquid pipeline is provided with washing liquid pump (P-101); the raw material feeding port comprises phosphogypsum feeding port and dilute acid feeding port; the height of the acid washing slurry outlet is lower than that of the acid washing clear liquid outlet.

3. The phosphogypsum recycling system of claim 1, wherein, The backflow filtrate pipeline is provided with backflow filtrate pump (P-104); the treatment slurry filter (F-102) is plate and frame filter.

4. The phosphogypsum recycling system of claim 2, wherein, The acid washing slurry treatment unit further comprises acid washing slurry filter (F-101) and dryer (D-101); the acid washing slurry filter (F-101) is provided with acid washing slurry feeding port, acid washing filtrate outlet and acid washing filter cake outlet; the dryer (D-101) is provided with acid washing filter cake feeding port, crude product outlet and tail gas outlet; the acid washing slurry feeding port is connected with the acid washing slurry outlet, the acid washing filter cake outlet is connected with the acid washing filter cake feeding port, and the crude product outlet is connected with the crude product feeding port.

5. The phosphogypsum recycling system of claim 4, wherein, The acid washing slurry treatment unit further comprises dryer dust collector (X-101), which is provided with tail gas inlet, second tail gas outlet and second crude product outlet; the tail gas inlet is connected with the tail gas outlet, and the second crude product outlet is connected with the crude product feeding port; The second tail gas outlet can be connected with the air inlet of the drying induced draft fan (C-101); the pickling slurry treatment unit further comprises a conveyor, the coarse product discharge port is connected with the feeding end of the conveyor, and the discharging end of the conveyor is connected with the coarse product feeding port.

6. The phosphogypsum recycling system of claim 5, wherein, The drying machine (D-101) is a drum dryer; the rotary drum of the drum dryer is an inclined and rotatable rotary drum; the rotary drum is internally provided with a forward direction scraper; the conveyor comprises a belt conveyor (L-101) and an elevator (L-102) connected in sequence; a pulverizer (X-102) is further arranged between the discharging end of the conveyor and the coarse product feeding port; the pulverizer (X-102) is a vibration pulverizer; and the pickling slurry filter (F-101) is a plate and frame filter.

7. The phosphogypsum recycling system of claim 5, wherein, A pickling slurry treatment unit can be further arranged between the pickling slurry discharge port and the coarse product feeding port, and the pickling slurry treatment unit comprises a pickling slurry filter (F-101), a drying machine (D-101), a drying machine dust collector (X-101), a belt conveyor (L-101), an elevator (L-102) and a pulverizer (X-102); The pickling slurry filter (F-101) is provided with a pickling slurry feeding port, a pickling filtrate discharge port and a pickling filter cake discharge port; the drying machine (D-101) is provided with a pickling filter cake feeding port, a coarse product discharge port and a tail gas outlet; and the drying machine dust collector (X-101) is provided with a tail gas inlet, a second tail gas outlet and a second coarse product discharge port; The pickling slurry feeding port is connected with the pickling slurry discharge port, the pickling filtrate discharge port is connected with the clear liquid feeding port through a clear liquid pipeline, a clear liquid pump (P-102) is arranged on the clear liquid pipeline, the pickling filter cake discharge port is connected with the pickling filter cake feeding port, the coarse product discharge port and the second coarse product discharge port are connected with the feeding end of the belt conveyor (L-101), the discharging end of the belt conveyor (L-101) is connected with the feeding end of the elevator (L-102), the discharging end of the elevator (L-102) is connected with the feeding end of the pulverizer (X-102), the discharging end of the pulverizer (X-102) is connected with the coarse product feeding port, the tail gas inlet is connected with the tail gas outlet, and the second tail gas outlet is connected with the air inlet of the drying induced draft fan (D-101).

8. The phosphogypsum recycling system of claim 1, wherein, The acid gas discharge port and the product discharge port can be further connected with a product treatment unit, the product treatment unit comprises an acid gas dust collector (X-103) and a bin (V-103), the acid gas dust collector (X-103) is provided with an acid gas feeding port, a second acid gas discharge port and a second product discharge port, the acid gas feeding port is connected with the acid gas discharge port, the second product discharge port and the product discharge port are connected with the feeding port of the bin (V-103), and the discharging end of the bin (V-103) is further connected with the feeding port of a product pulverizer (X-104).

9. The phosphogypsum recycling system of claim 1, wherein, The reaction furnace (R-101) is a cross-shaped reaction furnace; the fuel feeding port is provided with two, respectively located on both sides of the reaction furnace (R-101); the acid gas discharge port is located at the top of the reaction furnace (R-101); the product discharge port is located at the bottom of the reaction furnace (R-101).

10. The phosphogypsum recycling system of claim 1, wherein, The material of the hearth of the reaction furnace (R-101) is refractory brick.

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