A comprehensive recycling method and production line for waste residues from the production of ammonium paratungstate

Abstract

The invention relates to the technical field of solid waste residue recovery in the production of ammonium paratungstate, and discloses a comprehensive recovery and utilization method and production line for waste residue in the production of ammonium paratungstate, comprising adding water or calcium chloride mother liquor to the solid waste residue in the production of ammonium paratungstate, mixing and beating to form raw material slurry, mixing and stirring the raw material slurry with hydrochloric acid, and adjusting the pH value to 2 to 4; performing a first pressure filtration on the obtained slurry, adding acid or water to the filter residue obtained by the first pressure filtration to be beating to obtain an intermediate slurry, and adjusting the water content of the intermediate slurry to 32±5%, and adding sulfuric acid and auxiliary materials to the intermediate slurry for mixing and forming to obtain phosphate fertilizer. The invention also provides a comprehensive recovery and utilization production line for waste residue in the production of ammonium paratungstate. The invention can utilize the solid waste residue of ammonium paratungstate to produce phosphate fertilizer and prepare pure calcium chloride liquid.

Description

Technical Field

[0001] The invention relates to the technical field of solid waste residue recovery in the production of ammonium paratungstate, and in particular to a comprehensive recovery and utilization method and a production line for waste residue recovery in the production of ammonium paratungstate. Background Art

[0002] The main component of the waste residue from the production of ammonium paratungstate (APT) is calcium oxide, which is alkaline and belongs to hazardous chemical waste. In the existing technology, the waste residue containing non-ferrous metal elements such as copper, tungsten and molybdenum in the APT production process is mainly recycled as a by-product, and the metal elements such as copper, tungsten and molybdenum in the APT waste residue are extracted, thereby effectively reducing resource waste and improving resource utilization.

[0003] In the treatment of waste slag from the production of APT, the waste low-grade tungsten slag produced in the domestic APT production process is mainly sold to other resource recycling companies in the form of by-products to recover other trace metal elements such as copper, tin, and zinc, and smelt the waste slag. The phosphorus content in the waste slag from the production of APT is generally 3 to 8%. In the prior art, the recovery rate of phosphorus in the waste slag from the production of APT is low. When recycling the waste slag from the production of APT, if the phosphorus in the waste slag is not properly purified, it will cause water pollution. Summary of the invention

[0004] The purpose of the present invention is to provide a comprehensive recycling method and production line for waste residue produced in the production of ammonium paratungstate, so as to improve the comprehensive recycling effect of waste residue produced in the production of ammonium paratungstate.

[0005] In order to achieve the above object, the present invention provides a method for comprehensive recycling of waste residues produced by producing ammonium paratungstate, comprising the following steps:

[0006] S100, adding water or calcium chloride mother liquor to the solid waste residue produced by producing ammonium paratungstate, mixing and slurrying to prepare raw material slurry, mixing the raw material slurry with hydrochloric acid, and adjusting the pH value to 2 to 4;

[0007] S200, the slurry obtained in step S100 is filtered for the first time, and the filter residue obtained by the first filtering is slurried by adding dilute sulfuric acid or water, and the water content of the intermediate slurry is adjusted to 32±5%, sulfuric acid and auxiliary materials are added to the intermediate slurry for mixing and forming to obtain phosphate fertilizer, and the phosphate fertilizer is sent to the finished product warehouse. The mixing and forming process takes 6 to 10 minutes from feeding to discharging.

[0008] As a preferred solution, step S200 also includes:

[0009] The filtrate obtained by the first filtration is sequentially added with an oxidant, filtered for a second time, lime powder is added to the filtrate to remove metal ions and the pH is adjusted to 7 to 8, and the finished calcium chloride solution is obtained by the third filtration.

[0010] As a preferred solution, step S200 also includes:

[0011] When the phosphorus pentoxide content in the intermediate slurry is ≥24%, the auxiliary materials include mud or stone powder;

[0012] When the phosphorus pentoxide content in the intermediate slurry is less than 24%, the auxiliary material is calcium monohydrogen phosphate and / or heavy calcium and / or stone powder.

[0013] As a preferred solution, step S200 also includes:

[0014] The SO2 and SO3 generated when the intermediate slurry is mixed with sulfuric acid are absorbed and recovered to obtain dilute sulfuric acid, and the obtained dilute sulfuric acid is added to the filter residue obtained from the first filter press to be slurried to obtain the intermediate slurry.

[0015] The present invention also provides a comprehensive waste residue recycling production line for producing ammonium paratungstate, comprising a raw material slurry storage tank, a hydrochloric acid storage tank and an acidolysis pot, wherein the discharge ports of the hydrochloric acid storage tank and the raw material slurry storage tank are both connected to the feed port of the acidolysis pot, the discharge port of the acidolysis pot is connected to a first plate-frame filter press, the filtrate outlet of the first plate-frame filter press is connected to an intermediate tank, the filter residue outlet of the first plate-frame filter press is connected to a slurry storage tank through a conveyor belt, the slurry storage tank is provided with a liquid inlet for adding water, the slurry storage tank is connected to a mixer through a pump, the mixer is provided with a sulfuric acid inlet, and the mixer is used to mix slurry and sulfuric acid to produce a finished product of phosphorus-containing fertilizer;

[0016] The intermediate tank is connected to an oxidation pot, the oxidation pot is connected to a potassium permanganate solution storage tank, the discharge port of the oxidation pot is connected to a second plate-frame filter press via a pump, the filtrate outlet of the second plate-frame filter press is connected to a neutralization pot, the neutralization pot is provided with a lime powder feed port, the discharge port of the neutralization pot is connected to a third plate-frame filter press via a pump, and the filtrate outlet of the third plate-frame filter press is connected to a calcium chloride solution storage tank.

[0017] As a preferred solution, the raw material slurry storage tank is provided with a first feed port for adding calcium chloride mother liquor and a second feed port for adding waste residue from the production of ammonium paratungstate, and a raw material slurry stirring paddle is provided in the raw material slurry storage tank.

[0018] As a preferred embodiment, the acidolysis pot includes a pot body and a stirring shaft rotatably connected to the top of the pot body, the bottom of the pot body is connected to a pot bottom with a conical funnel structure, a slurry outlet is provided in the middle of the bottom of the pot bottom, and a calcium chloride slurry outlet is provided on the upper side wall of the pot body, the top of the pot body is connected to a pot cover, and a plurality of hydrochloric acid feed ports and a waste slurry feed port for producing ammonium paratungstate are provided on the bottom side wall of the pot body, the stirring shaft includes a shaft body and an acidolysis stirring paddle connected to the shaft body, the shaft body is rotatably connected to the middle of the pot cover, and the pot cover is also provided with an exhaust hole and a manhole.

[0019] As a preferred embodiment, the mixer comprises a mixing chamber and a formation chamber, both of which form closed chambers, the mixing chamber is used for mixing materials, the formation chamber is used for the formation of phosphate fertilizers, an overflow ring is provided on the side of the mixing chamber close to the formation chamber, a material channel is provided between the overflow ring and the top of the mixing chamber, a sulfuric acid feed port and a feeding port are provided on the top of the mixing chamber, a discharge port is provided at the bottom of one end of the formation chamber away from the mixing chamber, and a steam exhaust port and an auxiliary material feeding port are provided in the middle of the top of the formation chamber;

[0020] A stirring shaft is horizontally provided in the mixing chamber and the formation chamber, and a stirring driving device is connected to the stirring shaft outside the mixer in a transmission manner. A first stirring paddle is provided on the stirring shaft in the mixing chamber, and a second stirring paddle is provided on the stirring shaft in the formation chamber. The second stirring paddle can drive the material to move from the mixing chamber to the discharge port when the stirring shaft rotates.

[0021] As a preferred solution, the exhaust port is sequentially connected with a cyclone plate type gas-liquid separator and a spray tower for recovering SO2 and SO3.

[0022] As a preferred solution, the liquid outlet of the cyclone plate type gas-liquid separator and the liquid outlet of the spray tower transport the acid solution to the liquid inlet through a pipeline.

[0023] The present invention provides a comprehensive recycling method and production line for waste residue produced from ammonium paratungstate, which has the following beneficial effects:

[0024] 1. By recovering phosphorus from the waste residue of ammonium paratungstate production to produce phosphate fertilizer, the economic value of recycling the waste residue of ammonium paratungstate production can be improved, and environmental pollution caused by phosphorus in the waste residue of ammonium paratungstate production can be avoided;

[0025] 2. The present invention can be used to prepare phosphate fertilizer and pure calcium chloride solution at the same time, thereby improving the recycling efficiency of waste residue produced by producing ammonium paratungstate;

[0026] 3. In the process of phosphate fertilizer production, metal ions can be recovered by filtration, which improves the recycling rate of waste residues produced by ammonium paratungstate;

[0027] 4. The traditional phosphate fertilizer production process in the factory requires the phosphate fertilizer to be piled and matured in a maturation warehouse, which takes at least several days to several weeks. The present invention can quickly produce phosphate fertilizer, improve the production efficiency of phosphate fertilizer, and save storage costs in the phosphate fertilizer production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the steps of the comprehensive recycling method of waste residues from the production of ammonium paratungstate in an embodiment of the present invention;

[0029] Figure 2 It is a structural schematic diagram of a production line for comprehensive recycling of waste residues for producing ammonium paratungstate in an embodiment of the present invention;

[0030] Figure 3 Schematic diagram of the pot body structure of the acid hydrolysis pot in an embodiment of the present invention;

[0031] Figure 4 Schematic diagram of the stirring shaft structure of the acid hydrolysis pot in an embodiment of the present invention;

[0032] Figure 5 Schematic diagram of the stirring shaft structure of the mixer in the embodiment of the present invention;

[0033] Figure 6 yes Figure 5 Schematic diagram of the local structure at A in FIG.

[0034] Figure 7 It is a schematic diagram of the connection structure of the cyclone plate type gas-liquid separator of the comprehensive recycling production line of waste residue for producing ammonium paratungstate in the embodiment of the present invention;

[0035] Figure 8 is a schematic structural diagram of a raw material slurry storage tank in an embodiment of the present invention;

[0036] In the figure, 100, raw material slurry storage tank; 101, first feed inlet; 102, second feed inlet; 110, raw material slurry stirring paddle; 200, hydrochloric acid storage tank;

[0037] 300, acid hydrolysis pot; 310, pot body; 311, calcium chloride slurry outlet; 312, hydrochloric acid feed port; 313, APT waste slurry feed port; 314, PH detector installation hole; 320, stirring shaft; 321, shaft body; 322, acid hydrolysis stirring paddle; 323, stirring paddle group; 324, paddle; 330, pot bottom; 331, discharge port; 340, pot cover; 341, exhaust hole; 342, manhole;

[0038] 400, first plate and frame filter press; 500, middle tank; 600, slurry storage tank; 601, liquid inlet;

[0039] 700, mixer; 701, sulfuric acid inlet; 710, mixing chamber; 711, sulfuric acid feed port; 712, feeding port; 720, formation chamber; 721, discharge port; 722, exhaust port; 723, auxiliary material feeding port; 730, stirring shaft; 740, first stirring paddle; 750, second stirring paddle; 751, second stirring paddle; 760, stirring drive device; 770, overflow ring; 771, material channel; 780, cyclone plate type gas-liquid separator; 790, spray tower;

[0040] 800, oxidation pot; 810, potassium permanganate solution storage tank; 900, second plate and frame filter press; 910, neutralization pot; 911, lime powder feed port; 920, third plate and frame filter press; 930, calcium chloride solution storage tank. DETAILED DESCRIPTION

[0041] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0042] like Figures 1 to 8 As shown, a comprehensive recycling method and production line for waste residues from the production of ammonium paratungstate according to a preferred embodiment of the present invention improves the comprehensive utilization efficiency of waste residues from APT.

[0043] Based on the above technical solution, Figure 1 As shown, this embodiment provides a comprehensive recycling method for waste residue produced by producing ammonium paratungstate, comprising the following steps:

[0044] S100, adding water or calcium chloride mother liquor to the solid waste residue produced by producing ammonium paratungstate, mixing and slurrying to prepare raw material slurry, mixing the raw material slurry with hydrochloric acid, and adjusting the pH value to 2 to 4 after stirring.

[0045] When water or calcium chloride mother liquor is added to the solid waste residue produced by producing ammonium paratungstate and mixed and beaten to form raw material slurry, the beating process of the raw material slurry is completed in the beating tank. The hydrochloric acid is mixed with the raw material slurry to acidify the raw material slurry.

[0046] In step S100, the slurry prepared by mixing hydrochloric acid and raw material slurry can be made into calcium chloride mixed slurry through steps such as precipitation and filtration.

[0047] S200, the slurry obtained in step S100 is filtered for the first time, and the filter residue obtained by the first filtering is slurried by adding dilute sulfuric acid or water, and the water content of the intermediate slurry is adjusted to 32±5%, sulfuric acid and auxiliary materials are added to the intermediate slurry for mixing and forming to obtain phosphate fertilizer, and the phosphate fertilizer is sent to the finished product warehouse. The mixing and forming process takes 6 to 10 minutes from feeding to discharging.

[0048] The solid phase can be removed from the slurry obtained in step S100 by the first filter pressing to obtain a calcium chloride clear solution. Dilute sulfuric acid or water is added to the filter residue obtained by the first filter pressing to obtain an intermediate slurry, and the intermediate slurry is beaten in a phosphate ore beating tank. Here, the moisture content of the intermediate slurry is about 32%.

[0049] Specifically, the moisture content of the intermediate slurry may be 32±5%.

[0050] Among them, the raw material slurry and intermediate slurry are transported by slurry pumps.

[0051] The chemical reaction for preparing phosphate fertilizer is a process in step S200 in which sulfuric acid reacts with the waste slurry of APT containing phosphorus to generate superphosphate, which is a useful component of phosphate fertilizer.

[0052] In the production process of superphosphate, the chemical reaction can be divided into two stages. The first stage is the reaction of sulfuric acid with about 70% of Ca5(PO4)3F to generate phosphoric acid and calcium sulfate (Ca SO4·12H2O) crystals; the second stage is to use the phosphoric acid generated in the first stage to decompose the remaining about 30% of Ca5(PO4)3F to generate monocalcium phosphate monohydrate. The reaction speed of the second stage is very slow, generally taking several days to several weeks. Because the reaction time is too long, it must be moved from the formation room to the maturation warehouse to complete.

[0053] Here, APT waste residue is used as raw material. The particle size of APT waste residue is about 300 mesh, which is small. Due to the small particle size, it can react quickly when producing phosphate fertilizer. Compared with the traditional phosphate fertilizer production method, it can be directly mixed into one to quickly complete the above-mentioned second stage chemical reaction. The production process of phosphate fertilizer takes about 6-10 minutes from feeding to discharging, which greatly improves production efficiency and reduces the production cost of phosphate fertilizer.

[0054] Preferably, step S200 also includes:

[0055] The filtrate obtained by the first filtration is sequentially added with an oxidant, filtered for a second time, lime powder is added to the filtrate to remove metal ions and the pH is adjusted to 7 to 8, and the finished calcium chloride solution is obtained by the third filtration.

[0056] Here, the addition of an oxidant can remove the reducing agent in the filtrate obtained by the first filter pressing, and the precipitated waste residue can be filtered out by the second filter pressing. The third filter pressing can filter out metal impurities, such as magnesium slag, to obtain a pure calcium chloride solution.

[0057] Preferably, step S200 also includes:

[0058] When the phosphorus pentoxide content in the intermediate slurry is ≥24%, the auxiliary materials include mud or stone powder;

[0059] When the phosphorus pentoxide content in the intermediate slurry is less than 24%, the auxiliary material is calcium dihydrogen phosphate and / or heavy calcium and / or stone powder. The phosphorus content of the intermediate slurry can be increased by adding calcium dihydrogen phosphate, heavy calcium or stone powder.

[0060] Through the purification method of the present invention, the content of phosphorus pentoxide can be increased by 7 to 8%.

[0061] Preferably, step S200 also includes:

[0062] SO2 and SO3 generated when the intermediate slurry is mixed with sulfuric acid are dissolved and absorbed to obtain acid solution, and the obtained acid solution is added to the filter residue obtained from the first filter press to be slurried to obtain the intermediate slurry.

[0063] Here, the generated SO2 and SO3 can be recycled and reused, and the acid gas can be recycled and reused in the process of the present invention to avoid environmental pollution. At the same time, the amount of sulfuric acid can be reduced, thereby improving economic efficiency.

[0064] The present invention also provides a production line for comprehensive recycling of waste residues from the production of ammonium paratungstate, such as Figure 2 As shown, it includes a raw material slurry storage tank 100, a hydrochloric acid storage tank 200 and an acid hydrolysis pot 300. The discharge ports of the hydrochloric acid storage tank 200 and the raw material slurry storage tank 100 are connected to the feed port of the acid hydrolysis pot 300. The discharge port of the acid hydrolysis pot 300 is connected to a first plate and frame filter press 400. The filtrate outlet of the first plate and frame filter press 400 is connected to an intermediate tank 500. The filter residue outlet of the first plate and frame filter press 400 is connected to a slurry storage tank 600 through a conveyor belt. The slurry storage tank 600 is provided with a liquid inlet 601 for adding water. The slurry storage tank 600 is connected to a mixer 700 through a pump. The mixer 700 is provided with a sulfuric acid inlet 701. The mixer 700 is used to mix the slurry and sulfuric acid to produce a finished product of the phosphorus-containing fertilizer.

[0065] Among them, the raw material slurry storage tank 100 is used to store the raw material slurry. Here, a stirring device for slurrying can be set in the raw material slurry storage tank 100. The raw material slurry storage tank 100 is used as a raw material slurrying tank. The waste residue from the production of ammonium paratungstate is slurried to form a raw material slurry of the waste residue from the production of ammonium paratungstate, which is stored in the raw material slurry storage tank 100 after slurrying.

[0066] The intermediate tank 500 serves as an intermediate storage.

[0067] Here, the slurry storage tank 600 serves to store the decalcified slurry.

[0068] The liquid inlet 601 can be filled with water or acid.

[0069] Specifically, the middle tank 500 is connected to an oxidation pot 800, the oxidation pot 800 is connected to a potassium permanganate solution storage tank 810, the discharge port of the oxidation pot 800 is connected to a second plate and frame filter press 900 through a pump, the filtrate outlet of the second plate and frame filter press 900 is connected to a neutralization pot 910, the neutralization pot 910 is provided with a lime powder feed port 911, the discharge port of the neutralization pot 910 is connected to a third plate and frame filter press 920 through a pump, and the filtrate outlet of the third plate and frame filter press 920 is connected to a calcium chloride solution storage tank 930.

[0070] The potassium permanganate solution storage tank 810 is used to store a strong oxidant.

[0071] The neutralization pot 910 is used to adjust the pH of the slurry. The neutralization pot 910 includes a main structure as a container structure and a stirring paddle arranged in the main structure. The pH can be adjusted to 7 to 8 through the neutralization pot 910.

[0072] Preferably, if Figure 8 As shown, the raw material slurry storage tank 100 is provided with a first feed port 101 for adding calcium chloride mother liquor and a second feed port 102 for adding waste residue from producing ammonium paratungstate, and a raw material slurry stirring paddle 110 is provided in the raw material slurry storage tank 100 .

[0073] Preferably, if Figure 3 , Figure 4 As shown, the acid hydrolysis pot 300 is a reaction container for raw material slurry and hydrochloric acid.

[0074] Specifically, the acidolysis pot 300 includes a pot body 310 and a stirring shaft 320 rotatably connected to the top of the pot body 310, the bottom of the pot body 310 is connected to a pot bottom 330 with a conical funnel structure, a slurry outlet 331 is provided in the middle of the pot bottom 330, a calcium chloride slurry outlet 311 is provided on the upper side wall of the pot body 310, a pot cover 340 is connected to the top of the pot body 310, a plurality of hydrochloric acid feed ports 312 and APT waste residue slurry feed ports 313 are evenly provided on the bottom side wall of the pot body 310, the stirring shaft 320 includes a shaft body 321 and an acidolysis stirring paddle 322 connected to the shaft body 321, the shaft body 321 is rotatably connected to the middle of the pot cover 340, and the pot cover 340 is also provided with an exhaust hole 341 and a manhole 342.

[0075] Here, the raw material slurry prepared by adding water or calcium chloride mother liquor to the solid waste from producing APT (ammonium paratungstate) and mixing and beating is introduced into the APT waste slurry feed port 313 .

[0076] Among them, the hydrochloric acid feed port 312 and the APT waste slurry feed port 313 are at the same height, so that the hydrochloric acid feed port 312 and the APT waste slurry feed port 313 newly entering the acidolysis pot can start to react from the bottom of the acidolysis pot to facilitate sufficient reaction.

[0077] Here, the acid hydrolysis pot 300 is welded with a steel structure. A connecting flange is provided on the top of the stirring shaft 320, and a rotating flange matching the connecting flange on the top of the stirring shaft 320 is provided on the pot cover 340, wherein a thrust ball bearing can be installed between the rotating flange and the connecting flange, so that the stirring shaft 320 can rotate freely relative to the pot cover 340.

[0078] A valve is provided on the slurry outlet 331 , through which the waste residue and residues remaining after the reaction can be discharged.

[0079] Here, by setting the hydrochloric acid feed port 312 at the bottom of the pot body 310, the slurry in the pot body 310 can absorb the hydrogen chloride gas volatilized in the pot body 310 above the hydrochloric acid feed port 312, thereby avoiding the discharge of the hydrogen chloride gas.

[0080] Preferably, the acidolysis stirring paddle 322 includes three layers of stirring blade groups 323, which are respectively arranged at the bottom, middle and top of the stirring shaft 320, and each stirring blade group 323 includes 4 to 6 blades 324, respectively, and each blade 324 is evenly arranged on the circumference of the stirring shaft 320, thereby improving the reaction effect of the acidolysis process.

[0081] Preferably, a sampling port and an observation window 314 are also provided on the side wall of the pot body 310, wherein the slurry in the pot body 310 can be sampled through the sampling port, wherein the sampling port is obliquely arranged on the outer wall of the pot body 310, and a sampling pipe is connected to the sampling port through a thread.

[0082] A PH detection probe is installed in the PH detector installation hole 314 to detect the PH value in the pot body 310 and control the reaction process.

[0083] Optionally, there are two PH detection probes, which are respectively arranged at the bottom and the middle of the pot body, so as to detect the PH value from different heights of the pot body 310, that is, to accurately monitor the entire reaction process in the pot body 310.

[0084] Preferably, a portion of the acidolysis stirring paddle 322 inside the pot body 310 is provided with glass fiber cloth on the surface, and the glass fiber cloth improves the corrosion resistance and heat resistance of the acidolysis stirring paddle 322 .

[0085] Preferably, if Figure 5 , Figure 6As shown, the mixer 700 includes a mixing chamber 710 and a formation chamber 720, both of which form a closed chamber. The mixing chamber 710 is used for mixing materials, and the formation chamber 720 is used for forming phosphate fertilizers. An overflow ring 770 is provided on one side of the mixing chamber 710 close to the formation chamber 720. A material channel 771 is provided between the overflow ring 770 and the top of the mixing chamber 710. When the material in the mixing chamber 710 overflows, the slurry can reach the formation chamber 720 from the mixing chamber 710 through the material channel 771. The overflow ring 770 can be a steel plate welded to the inner side wall of the mixing chamber 710.

[0086] Preferably, a sulfuric acid feed port 711 and a feeding port 712 are provided at the top of the mixing chamber 710, a discharge port 721 is provided at the bottom of the formation chamber 720 away from the mixing chamber 710, and a steam exhaust port 722 and an auxiliary material feeding port 723 are provided in the middle of the top of the formation chamber 720.

[0087] When in use, sulfuric acid and intermediate slurry can be introduced from the sulfuric acid feed port 711 and the feed port 712 respectively, and the auxiliary material feed port 723 is used to feed auxiliary materials.

[0088] In order to recover the SO 2 and SO 3 gases in the formation chamber 720 , a fan is connected to the exhaust port 722 to extract the SO 2 and SO 3 gases, and external air enters the formation chamber 720 from the discharge port 721 .

[0089] By arranging the exhaust port 722 in the middle of the top of the mixing chamber 710, it is possible to prevent external air from being directly drawn out by the exhaust port 722 from behind the discharge port 721, thereby improving the recovery effect of SO2 and SO3 gases.

[0090] Specifically, a stirring shaft 730 is horizontally inserted through the mixing chamber 710 and the formation chamber 720. The stirring shaft 730 is connected to a stirring driving device 760 outside the mixer 700. A first stirring paddle 740 is provided on the stirring shaft 730 in the mixing chamber 710. A second stirring paddle 750 is provided on the stirring shaft 730 in the formation chamber 720. The second stirring paddle 750 can drive the material to move from the mixing chamber 710 to the discharge port 721 as the stirring shaft 730 rotates.

[0091] Here, the temperature during the mixing process is 120 to 130° C., and the discharge temperature is about 90° C. The reactants in the formation chamber 720 mainly include dilute sulfuric acid, superphosphate, silicon tetrafluoride, and hydrogen fluoride gas.

[0092] The stirring driving device 760 includes a reducer and a motor which are connected to each other.

[0093] Specifically, the second stirring paddle 750 includes a plurality of second stirring blades 751 arranged on the circumference of the stirring shaft 730. The second stirring blades 751 are in the shape of a flat plate. The plate surface of the second stirring blades 751 is inclined relative to the stirring shaft 730. Figure 5 As shown, the angle between the plate surface of the second stirring blade 751 and the axis of the stirring shaft 730 is α, so that the second stirring blade 751 can drive the material from the mixing chamber 710 to the discharge port 721 when rotating.

[0094] The value of the angle α may be 15 degrees, 25 degrees or 30 degrees.

[0095] Preferably, the mixing chamber 710 is lined with a refractory brick layer, and the thickness of the refractory brick layer is 240 cm to 260 cm, which can improve the heat resistance and corrosion resistance of the mixing chamber 710.

[0096] Preferably, the formation chamber 720 is lined with a granite anti-corrosion layer, and the gaps in the granite anti-corrosion layer are caulked with diabase mortar, which can provide long-term corrosion resistance.

[0097] Preferably, the surface of the first stirring paddle 740 is coated with a diabase clay layer, which can improve the corrosion resistance of the second stirring paddle.

[0098] Preferably, the surface of the second stirring paddle 750 is provided with a water glass mastic layer and a white cast iron layer in sequence from the inside to the outside, which can improve the corrosion resistance of the second stirring paddle.

[0099] Preferably, if Figure 7 As shown, the exhaust port 722 is connected in sequence with a cyclone plate type gas-liquid separator 780 and a spray tower 790 for recovering SO2 and SO3. The liquid in the water vapor can be directly separated by the cyclone plate type gas-liquid separator 780, and the water and acid liquid are sprayed in the spray tower. The SO2 and SO3 gases are contacted with the water and acid liquid through spraying in the spray tower 790, and the SO2 and SO3 gases can be absorbed by the water and acid liquid to form acid liquid.

[0100] Preferably, the liquid outlet of the cyclone plate type gas-liquid separator 780 and the liquid outlet of the spray tower 790 transport the acid liquid to the circulation tank 715 through a pipeline, so that SO2 and SO3 can be recovered and utilized.

[0101] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A method for comprehensive recycling of waste residues from the production of ammonium paratungstate, characterized in that: The steps include: S100, adding water or calcium chloride mother liquor to the solid waste residue produced by producing ammonium paratungstate, mixing and slurrying to prepare raw material slurry, mixing the raw material slurry with hydrochloric acid, and adjusting the pH value to 2 to 4; S200, the slurry obtained in step S100 is filtered for the first time, dilute sulfuric acid or water is added to the filter residue obtained by the first filtering to obtain an intermediate slurry, and the water content of the intermediate slurry is adjusted to 32±5%, sulfuric acid and auxiliary materials are added to the intermediate slurry for mixing and forming to obtain phosphate fertilizer, and the phosphate fertilizer is sent to the finished product warehouse, and the mixing and forming process takes 6 to 10 minutes from feeding to discharging; Step S200 also includes: The filtrate obtained by the first filtration is sequentially added with an oxidant, filtered for a second time, lime powder is added to the filtrate to remove metal ions and the pH is adjusted to 7 to 8, and the calcium chloride liquid product is obtained by the third filtration; Step S200 also includes: When the phosphorus pentoxide content in the intermediate slurry is ≥24%, the auxiliary materials include mud or stone powder; When the phosphorus pentoxide content in the intermediate slurry is less than 24%, the auxiliary material is calcium monohydrogen phosphate and / or heavy calcium and / or stone powder.

2. The method for comprehensive recycling of waste residues from the production of ammonium paratungstate according to claim 1, characterized in that: Step S200 also includes: The SO2 and SO3 generated when the intermediate slurry is mixed with sulfuric acid are absorbed and recovered to obtain dilute sulfuric acid, and the obtained dilute sulfuric acid is added to the filter residue obtained from the first filter press to be slurried to obtain the intermediate slurry.

3. A comprehensive recycling production line for waste residues from the production of ammonium paratungstate, characterized in that: The method for comprehensive recycling of waste residues from the production of ammonium paratungstate according to claim 1 or 2 comprises a raw material slurry storage tank, a hydrochloric acid storage tank and an acidolysis pot, wherein the discharge ports of the hydrochloric acid storage tank and the raw material slurry storage tank are both connected to the feed port of the acidolysis pot, the discharge port of the acidolysis pot is connected to a first plate-frame filter press, the filtrate outlet of the first plate-frame filter press is connected to an intermediate tank, the filter residue outlet of the first plate-frame filter press is connected to a slurry storage tank through a conveyor belt, the slurry storage tank is provided with a liquid inlet for adding water, the slurry storage tank is connected to a mixer through a pump, the mixer is provided with a sulfuric acid inlet, and the mixer is used to mix the slurry and sulfuric acid to produce a finished product of superphosphate; The intermediate tank is connected to an oxidation pot, the oxidation pot is connected to a potassium permanganate solution storage tank, the discharge port of the oxidation pot is connected to a second plate-frame filter press via a pump, the filtrate outlet of the second plate-frame filter press is connected to a neutralization pot, the neutralization pot is provided with a lime powder feed port, the discharge port of the neutralization pot is connected to a third plate-frame filter press via a pump, and the filtrate outlet of the third plate-frame filter press is connected to a calcium chloride solution storage tank.

4. The production line for comprehensive recycling of waste residues from the production of ammonium paratungstate as claimed in claim 3, characterized in that: The raw material slurry storage tank is provided with a first feed inlet for adding calcium chloride mother liquor and a second feed inlet for adding waste residue from the production of ammonium paratungstate, and a raw material slurry stirring paddle is provided in the raw material slurry storage tank.

5. The production line for comprehensive recycling of waste residues from the production of ammonium paratungstate as claimed in claim 3, characterized in that: The acidolysis pot comprises a pot body and a stirring shaft rotatably connected to the top of the pot body, the bottom of the pot body is connected to a pot bottom with a conical funnel structure, a slurry outlet is arranged in the middle of the bottom of the pot bottom, a calcium chloride slurry outlet is arranged on the upper side wall of the pot body, the top of the pot body is connected to a pot cover, a plurality of hydrochloric acid feed ports and a waste residue slurry feed port for producing ammonium paratungstate are arranged on the bottom side wall of the pot body, the stirring shaft comprises a shaft body and an acidolysis stirring paddle connected to the shaft body, the shaft body is rotatably connected to the middle of the pot cover, and an exhaust hole and a manhole are also arranged on the pot cover.

6. The production line for comprehensive recycling of waste residues from the production of ammonium paratungstate as claimed in claim 3, characterized in that: The mixer comprises a mixing chamber and a formation chamber, both of which form a closed chamber. The mixing chamber is used to mix materials, and the formation chamber is used to form phosphate fertilizer. An overflow ring is provided on the side of the mixing chamber close to the formation chamber, and a material channel is provided between the overflow ring and the mixing chamber. A sulfuric acid feed port and a feeding port are provided on the top of the mixing chamber, a discharge port is provided at the bottom of one end of the formation chamber away from the mixing chamber, and a steam exhaust port and an auxiliary material feeding port are provided in the middle of the top of the formation chamber. A stirring shaft is horizontally provided in the mixing chamber and the formation chamber, and a stirring driving device is connected to the stirring shaft outside the mixer in a transmission manner. A first stirring paddle is provided on the stirring shaft in the mixing chamber, and a second stirring paddle is provided on the stirring shaft in the formation chamber. The second stirring paddle can drive the material to move from the mixing chamber to the discharge port when the stirring shaft rotates.

7. The production line for comprehensive recycling of waste residues from the production of ammonium paratungstate as claimed in claim 6, characterized in that: The exhaust port is sequentially connected with a cyclone plate type gas-liquid separator and a spray tower for recovering SO2 and SO3.

8. The production line for comprehensive recycling of waste residues from the production of ammonium paratungstate as claimed in claim 7, characterized in that: The liquid outlet of the cyclone plate type gas-liquid separator and the liquid outlet of the spray tower transport the acid liquid to the circulation tank through pipelines.

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