Iron resource utilization process for hydrometallurgy high iron sulfate system

Abstract

The invention provides a hydrometallurgy high-iron sulfate system iron resource utilization process which comprises the following steps: step 1, an extraction process of high-iron sulfate system iron ions: step S11, adjusting the pH value of a to-be-extracted sulfate solution, carrying out multi-stage extraction by using a saponified extraction agent which takes kerosene as a solvent, and carrying out solid-liquid separation; extracting iron ions in the sulfate solution to be extracted to an organic phase; step S12, carrying out multi-stage back extraction on the loaded organic phase obtained in the step S11 by using hydrochloric acid; step S13, carrying out multi-stage washing on the anti-iron organic phase obtained in the step S12 by using pure water; step S14, neutralizing the ferric chloride wastewater containing hydrochloric acid obtained in the step S13 with the ferric oxide obtained in the step 2; step S15, concentrating the wastewater containing ferric chloride obtained in the step S14 to obtain a concentrated ferric chloride solution; 2, treating and separating iron-containing waste hydrochloric acid and waste water generated after extraction by an incineration method; and step 3, refining hydrochloric acid. According to the process, iron in a high iron sulfate system can be separated in the form of dry iron oxide, the purity of the iron oxide can reach 99% or above, the iron oxide can be completely used as a high-added-value product, and hydrochloric acid is recycled.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrometallurgy, relates to a high-iron sulfate system, and particularly relates to a process for the resource utilization of iron in a high-iron sulfate system in hydrometallurgy. Background Art

[0002] In the fields of hydrometallurgy, comprehensive utilization of waste resources, etc., there are problems of separating low-value element iron from high-value elements such as nickel, cobalt, copper, rare earths, aluminum, etc. Many methods have been developed, mainly including three types: precipitation method, ion exchange resin method, and solvent extraction method. The precipitation method is usually applied to separation and purification processes with low requirements for iron removal efficiency. Generally, the iron removal rate is 60%, and it cannot achieve the effect of deep iron removal. During the precipitation process, other valuable metals will inevitably co-precipitate with iron, resulting in losses and generating a large amount of hazardous waste such as iron vanadate containing heavy metals. Ion exchange resins have high efficiency and high selectivity, but due to the relatively low mass transfer rate and limited iron loading capacity, they are not suitable for separation systems with high iron content and are only economically feasible when the iron content is relatively low. The solvent extraction method for iron removal has the advantages of selectivity, high extraction efficiency, large loading capacity, and low energy consumption, but high-concentration hydrochloric acid must be used for back-extracting iron. In the solvent extraction method, organic reagents such as acidic phosphoric esters, neutral extractants, and amine extractants all perform well in iron removal from solutions, especially acidic phosphoric ester extractants such as P204 and P507 are particularly outstanding in iron removal from metal sulfate solutions such as nickel, cobalt, and aluminum. However, all these methods remove iron as an impurity, and a large amount of hazardous waste will be generated after iron removal. For example, in the process of wet smelting nickel, every 1 ton of iron ions removed will produce more than 4 tons of jarosite slag. The composition of these solid wastes fluctuates greatly, containing 18% - 25% iron, 10% - 13% sulfur, 4% - 9% sodium, 1% - 4% silicon, 0.05% - 7.00% nickel, 0.1% - 2.0% cobalt, 0.5% - 1.0% copper, and other impurity elements such as lead, barium, zinc, manganese, calcium, magnesium, etc. together account for about 1%, which are typical hazardous wastes. Using the solvent extraction method for iron removal, although the amount of solid waste is reduced, a large amount of waste hydrochloric acid is generated. Every 1 ton of iron removed will produce 25 - 28 tons of about 4N waste hydrochloric acid and a large amount of wastewater. In the current situation where environmental protection requirements are becoming increasingly strict, how to solve these problems has become a major problem facing relevant enterprises and technical personnel in the fields of hydrometallurgy and environmental protection. Summary of the Invention

[0003] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a process for the resource utilization of iron in a high-iron sulfate system in hydrometallurgy to solve the technical problem that the quality of the separated products in the existing technology needs to be further improved.

[0004] To solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0005] A process for the resource utilization of iron in a hydrometallurgical high-iron sulfate system, which process comprises the following steps:

[0006] Step 1, the extraction process of iron ions in the high-iron sulfate system:

[0007] Step S11, adjust the pH value of the sulfate solution to be extracted, and perform multi-stage extraction with a saponified extractant using kerosene as the solvent to extract the iron ions in the sulfate solution to be extracted into the organic phase, obtaining a loaded organic phase, and the raffinate enters the subsequent process.

[0008] Step S12, perform multi-stage back-extraction on the loaded organic phase obtained in Step S11 with hydrochloric acid to obtain an organic phase after iron removal and a ferric chloride solution containing hydrochloric acid.

[0009] Step S13, perform multi-stage washing on the organic phase after iron removal obtained in Step S12 with pure water to obtain an unloaded organic phase and ferric chloride wastewater containing hydrochloric acid; the unloaded organic phase is recycled.

[0010] Step S14, neutralize the ferric chloride wastewater containing hydrochloric acid obtained in Step S13 with the iron oxide obtained in Step 2 to obtain ferric chloride wastewater.

[0011] Step S15, concentrate the ferric chloride wastewater obtained in Step S14 to obtain a concentrated ferric chloride solution, and merge the concentrated ferric chloride solution with the ferric chloride solution containing hydrochloric acid obtained in Step S12 to form a merged solution.

[0012] Step 2, the separation process of iron and hydrochloric acid after extraction:

[0013] Step S21, incinerate the merged solution obtained in Step S15. The ferric chloride in the merged solution reacts with water to form iron oxide and hydrogen chloride. The iron oxide grows into particles and is discharged after cooling to obtain an iron oxide product.

[0014] Step S22, the hydrogen chloride + water vapor generated in Step S21 is separated to obtain a mixed gas and iron oxide dust. The iron oxide dust returns to be remelted and grows into particles again. The mixed gas recovers heat to obtain a cooled mixed gas.

[0015] Step S23, spray and absorb the cooled mixed gas obtained in Step S22 to obtain crude hydrochloric acid and primary tail gas.

[0016] Step S24, the primary tail gas obtained in Step S23 is cooled and then absorbed to obtain crude hydrochloric acid and secondary tail gas. The secondary tail gas is discharged after cooling.

[0017] Step 3, the refining process of hydrochloric acid:

[0018] Step S31: Ion-exchange the crude hydrochloric acid obtained in Step 2 to obtain refined hydrochloric acid and regenerated wastewater containing residual iron ions.

[0019] Step S32: Finally, the refined hydrochloric acid obtained is returned to Step 1 for recycling.

[0020] Step S33: The regenerated wastewater containing residual iron ions is returned to Step 1 for recycling.

[0021] This process uses an iron ion extraction and separation device to perform the iron ion extraction process in a high-iron sulfate system; this process uses a separation device for iron and hydrochloric acid after extraction to perform the separation process of iron and hydrochloric acid after extraction; this process uses a hydrochloric acid refining device to perform the hydrochloric acid refining process.

[0022] The described iron ion extraction and separation device includes an extraction device with a stirring mixer and a separation chamber. The extraction device with a stirring mixer and a separation chamber is divided into an iron extraction section, an iron stripping section, and a washing section; the loaded organic phase discharge port of the iron extraction section is connected to the feed port of the iron stripping section; the organic phase discharge port after iron stripping of the iron stripping section is connected to the feed port of the washing section.

[0023] The feed port of the sulfate solution to be extracted in the iron extraction section is connected to a pH adjustment tank for the sulfate solution to be extracted; the feed port of the saponified extractant in the iron extraction section is connected to the discharge port of a saponification tank. One feed port of the saponification tank is connected to the discharge port of an extractant solution tank using kerosene as a solvent.

[0024] The hydrochloric acid feed port of the iron stripping section is connected to the discharge port of a hydrochloric acid preparation tank. One feed port of the hydrochloric acid preparation tank is connected to a recycled hydrochloric acid pipeline; the discharge port of the spent hydrochloric acid after iron stripping in the iron stripping section is connected to the feed port of a spent hydrochloric acid receiving tank.

[0025] The wastewater discharge port of the washing section is connected to the feed port of a wastewater collection and neutralization tank.

[0026] The iron ion extraction and separation device also includes a triple-effect evaporator. The triple-effect evaporator includes a first evaporator and a third vapor-liquid separator. The tube-side feed port of the first evaporator is connected to the wastewater collection and neutralization tank for feeding; the liquid discharge port of the third vapor-liquid separator is connected to the feed port of the spent hydrochloric acid receiving tank.

[0027] The described separation device for iron and hydrochloric acid after extraction includes a waste hydrochloric acid fluidized bed incinerator. The bottom discharge port of the waste hydrochloric acid fluidized bed incinerator is connected to an iron oxide screw discharger, and the iron oxide screw discharger is connected to the feed port of an iron oxide bin. The top discharge port of the waste hydrochloric acid fluidized bed incinerator is connected to a cyclone dust collector. The solid discharge port of the cyclone dust collector is connected to the furnace chamber of the waste hydrochloric acid fluidized bed incinerator, and the gas outlet of the cyclone dust collector is connected to the tube-side inlet of a waste heat utilization heat exchanger. The tube-side outlet of the waste heat utilization heat exchanger is connected to the inlet of a hydrochloric acid spray absorption tower.

[0028] The outlet of the hydrochloric acid spray absorption tower is connected to the tube-side inlet of a first tail gas cooler. The tube-side outlet of the first tail gas cooler is connected to one inlet of a venturi air dissolver. The other inlet of the venturi air dissolver is connected to a crude hydrochloric acid receiving tank. The outlet of the venturi air dissolver is connected to the tube-side inlet of a second tail gas cooler. The tube-side outlet of the second tail gas cooler is connected to a chimney.

[0029] The described hydrochloric acid refining device includes at least one resin exchange tower. One discharge port of the resin exchange tower is connected to a refined hydrochloric acid collection tank, and the other discharge port of the resin exchange tower is connected to a regenerated wastewater collection tank.

[0030] The discharge port of the anti-iron waste hydrochloric acid receiving tank is connected to the feed port of the waste hydrochloric acid fluidized bed incinerator. The crude hydrochloric acid receiving tank is connected to one feed port of the resin exchange tower. The other feed port of the resin exchange tower is connected to the pure water pipeline. The refined hydrochloric acid collection tank is connected to the recycled hydrochloric acid pipeline. The regenerated wastewater collection tank is connected to a wastewater collection and neutralization tank, and the wastewater collection and neutralization tank is connected to one discharge port of the iron oxide bin.

[0031] Compared with the prior art, the present invention has the following technical effects:

[0032] (Ⅰ) The process of the present invention can separate iron in the high-iron sulfate system in the form of dry iron oxide, and the purity of the iron oxide can reach more than 99%, which can be fully utilized as a high-value-added product.

[0033] (Ⅱ) The hydrochloric acid obtained by the process of the present invention has high purity and high concentration, and can be fully recycled, significantly reducing the consumption of process hydrochloric acid, treating waste hydrochloric acid and reducing the operating cost.

[0034] (Ⅲ) The process of the present invention uses waste heat to perform multi-effect distillation treatment on wastewater, recovering ferric chloride in the wastewater and effectively treating the wastewater.

[0035] (Ⅳ) The process of the present invention can basically operate continuously, which is very conducive to subsequent automated design. Description of the Drawings

[0036] Figure 1 It is a schematic diagram of the overall structure of the iron resource utilization system in the hydrometallurgical high-iron sulfate system.

[0037] Figure 2(a) is a schematic diagram of the structure of the extraction and separation device for iron ions.

[0038] Figure 2(b) is an enlarged schematic diagram of the extraction equipment with a stirring mixer and a separation chamber in Figure 2(a).

[0039] Figure 2(c) is an enlarged schematic diagram of the right part where the iron extraction section is located in Figure 2(a).

[0040] Figure 2(d) is an enlarged schematic diagram of the middle part where the iron stripping section is located in Figure 2(a).

[0041] Figure 2(e) is an enlarged schematic diagram of the left part where the washing section is located in Figure 2(a).

[0042] Figure 2(f) is an enlarged schematic diagram of the triple-effect evaporator in Figure 2(a).

[0043] Figure 3 It is a schematic diagram of the structure of the separation device for iron and hydrochloric acid after extraction.

[0044] Figure 4 It is a schematic diagram of the structure of the hydrochloric acid refining device.

[0045] The meanings of each label in the figure are as follows: 1 - extraction and separation device for iron ions, 2 - separation device for iron and hydrochloric acid after extraction, 3 - hydrochloric acid refining device, 4 - pipeline, 5 - valve, 6 - transfer pump.

[0046] 101 - iron extraction section, 102 - iron stripping section, 103 - washing section, 104 - pH adjustment tank for the sulfate solution to be extracted, 105 - pipeline for the sulfate solution to be extracted, 106 - dilute sulfuric acid pipeline, 107 - saponification tank, 108 - extractant solution tank with kerosene as the solvent, 109 - liquid alkali pipeline, 110 - hydrochloric acid preparation tank, 111 - pure water pipeline, 112 - concentrated hydrochloric acid pipeline, 113 - recycled hydrochloric acid pipeline, 114 - iron stripping waste hydrochloric acid receiving tank, 115 - waste water collection and neutralization tank, 116 - triple-effect evaporator.

[0047] 201 - Waste hydrochloric acid fluidized bed incinerator, 202 - Gas pipeline, 203 - Air pipeline, 204 - Iron oxide spiral discharger, 205 - Iron oxide bin, 206 - Cyclone dust collector, 207 - Waste heat utilization heat exchanger, 208 - Hydrochloric acid spray absorption tower, 209 - First tail gas cooler, 210 - Venturi air dissolver, 211 - Crude hydrochloric acid receiving tank, 212 - Second tail gas cooler, 213 - Exhaust stack, 214 - Cooling water pipeline, 215 - Softened water pipeline, 216 - Recovered steam pipeline, 217 - Spray liquid cooler.

[0048] 301 - Resin exchange tower, 302 - Refined hydrochloric acid collection tank, 303 - Regenerated wastewater collection tank.

[0049] 10101 - Feed inlet for sulfate solution to be extracted, 10102 - Feed inlet for saponified extractant, 10103 - Raffinate outlet.

[0050] 10201 - Hydrochloric acid feed inlet, 10202 - Outlet for anti - iron waste hydrochloric acid.

[0051] 10301 - Pure water feed inlet, 10302 - Wastewater outlet, 10303 - Unloading organic phase outlet.

[0052] 11601 - First evaporator, 11602 - First vapor - liquid separator, 11603 - Second evaporator, 11604 - Second vapor - liquid separator, 11605 - Third evaporator, 11606 - Third vapor - liquid separator.

[0053] The following further elaborates on the specific content of the present invention in conjunction with embodiments. Specific embodiments

[0054] It should be noted that all raw materials and equipment in the present invention, unless otherwise specified, are all known raw materials and equipment in the prior art.

[0055] Complying with the above - mentioned technical solutions, the following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent transformations made on the basis of the technical solutions of this application fall within the protection scope of the present invention.

[0056] Embodiment:

[0057] This embodiment provides a process for the resource utilization of iron in a high - iron sulfate system in hydrometallurgy. This process uses an iron ion extraction and separation device 1 to perform the extraction process of iron ions in the high - iron sulfate system; this process uses a separation device 2 for iron and hydrochloric acid after extraction to perform the separation process of iron and hydrochloric acid after extraction; this process uses a hydrochloric acid refining device 3 to perform the hydrochloric acid refining process.

[0058] As Figures 2(a) to 2(f)As shown in the figure, the extraction and separation device 1 of iron ions includes an extraction device with a stirring mixer and a separation chamber. The extraction device with a stirring mixer and a separation chamber is divided into an iron extraction section 101, an iron stripping section 102, and a washing section 103. The outlet of the loaded organic phase of the iron extraction section 101 is connected to the inlet of the iron stripping section 102. The outlet of the organic phase after iron stripping in the iron stripping section 102 is connected to the inlet of the washing section 103.

[0059] As Figures 2(a) to 2(f) shown, the inlet 10101 of the sulfate solution to be extracted in the iron extraction section 101 is connected to the pH adjustment tank 104 of the sulfate solution to be extracted. The inlet 10102 of the saponified extractant in the iron extraction section 101 is connected to the outlet of the saponification tank 107. One inlet of the saponification tank 107 is connected to the outlet of the extractant solution tank 108 with kerosene as the solvent.

[0060] As Figures 2(a) to 2(f) shown, the hydrochloric acid inlet 10201 in the iron stripping section 102 is connected to the outlet of the hydrochloric acid preparation tank 110. One inlet of the hydrochloric acid preparation tank 110 is connected to the recycled hydrochloric acid pipeline 113. The outlet 10202 of the waste hydrochloric acid after iron stripping in the iron stripping section 102 is connected to the inlet of the waste hydrochloric acid receiving tank 114.

[0061] As Figures 2(a) to 2(f) shown, the wastewater outlet 10302 in the washing section 103 is connected to the inlet of the wastewater collection and neutralization tank 115.

[0062] As Figures 2(a) to 2(f) shown, the extraction and separation device 1 of iron ions further includes a triple-effect evaporator 116. The triple-effect evaporator 116 includes a first evaporator 11601 and a third vapor-liquid separator 11606. The tube-side inlet of the first evaporator 11601 is connected to the wastewater collection and neutralization tank 115 for feeding. The liquid outlet of the third vapor-liquid separator 11606 is connected to the inlet of the waste hydrochloric acid receiving tank 114.

[0063] As Figure 3 shown, the separation device 2 of iron and hydrochloric acid after extraction includes a waste hydrochloric acid fluidized bed incinerator 201. The bottom outlet of the waste hydrochloric acid fluidized bed incinerator 201 is connected to an iron oxide screw discharger 204, and the iron oxide screw discharger 204 is connected to the inlet of an iron oxide bin 205. The top outlet of the waste hydrochloric acid fluidized bed incinerator 201 is connected to a cyclone dust collector 206. The solid outlet of the cyclone dust collector 206 is connected to the furnace chamber of the waste hydrochloric acid fluidized bed incinerator 201. The gas outlet of the cyclone dust collector 206 is connected to the tube-side inlet of a waste heat utilization heat exchanger 207. The tube-side outlet of the waste heat utilization heat exchanger 207 is connected to the inlet of a hydrochloric acid spray absorption tower 208.

[0064] As Figure 3As shown in the figure, the gas outlet of the hydrochloric acid spray absorption tower 208 is connected to the tube side inlet of the first tail gas cooler 209. The tube side outlet of the first tail gas cooler 209 is connected to one inlet of the Venturi air dissolver 210. The other inlet of the Venturi air dissolver 210 is connected to the crude hydrochloric acid receiving tank 211. The outlet of the Venturi air dissolver 210 is connected to the tube side inlet of the second tail gas cooler 212. The tube side outlet of the second tail gas cooler 212 is connected to the exhaust stack 213.

[0065] As Figure 4 shown, the hydrochloric acid refining device 3 includes at least one resin exchange tower 301. One discharge port of the resin exchange tower 301 is connected to the refined hydrochloric acid collection tank 302, and the other discharge port of the resin exchange tower 301 is connected to the regenerated wastewater collection tank 303.

[0066] As Figure 1 shown, the discharge port of the anti-ferrous waste hydrochloric acid receiving tank 114 is connected to the feed inlet of the waste hydrochloric acid fluidized bed incinerator 201; the crude hydrochloric acid receiving tank 211 is connected to one feed inlet of the resin exchange tower 301; the other feed inlet of the resin exchange tower 301 is connected to the pure water pipeline 111; the refined hydrochloric acid collection tank 302 is connected to the recovered hydrochloric acid pipeline 113; the regenerated wastewater collection tank 303 is connected to the wastewater collection and neutralization tank 115, and the wastewater collection and neutralization tank 115 is connected to one discharge port of the iron oxide storage bin 205.

[0067] Specifically, the process includes the following steps:

[0068] Step 1, the extraction process of iron ions in the high-iron sulfate system:

[0069] Step S11, adjust the pH value of the sulfate solution to be extracted in the sulfate solution pH adjustment tank 104 to be extracted. Use the saponified extractant with kerosene as the solvent for multi-stage extraction in the iron extraction section 101 to extract the iron ions in the sulfate solution to be extracted into the organic phase to obtain the loaded organic phase, and the raffinate enters the subsequent process.

[0070] In step S11, adjust the pH value of the sulfate solution to be extracted to 1-3.

[0071] In step S11, the extractant is P204 extractant (i.e., bis(2-ethylhexyl) phosphate; bis(2-ethylhexyl) phosphoric acid ester) or P507 extractant (i.e., 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester); the kerosene is petroleum fractionated and hydrogenated kerosene or coal-derived kerosene; the mass ratio of the extractant to kerosene is 1:(3-4).

[0072] In step S11, the saponification rate of the extractant is 50-70%, and the oil-water ratio is 1:(1-3).

[0073] In step S11, the number of extraction stages is 6-10.

[0074] Step S12: The loaded organic phase obtained in step S11 is subjected to multi-stage back-extraction with hydrochloric acid in the anti-ferric stage 102 to obtain the post-anti-ferric organic phase and a ferric chloride solution containing hydrochloric acid.

[0075] In step S12, the number of back-extraction stages is 4 to 6.

[0076] Step S13: The post-anti-ferric organic phase obtained in step S12 is subjected to multi-stage washing with pure water in the washing stage 103 to obtain the unloaded organic phase and ferric chloride wastewater containing hydrochloric acid; the unloaded organic phase is recycled to the extractant solution tank 108 with kerosene as the solvent.

[0077] In step S13, the number of washing stages is 4 to 6.

[0078] Step S14: The ferric chloride wastewater containing hydrochloric acid obtained in step S13 is neutralized with the iron oxide obtained in step two in the wastewater collection and neutralization tank 115 to obtain ferric chloride-containing wastewater.

[0079] In step S14, the pH of neutralization is 3.5 - 4.

[0080] Step S15: The ferric chloride-containing wastewater obtained in step S14 is concentrated by a triple-effect evaporator 116 to obtain a concentrated ferric chloride solution. The concentrated ferric chloride solution is combined with the ferric chloride solution containing hydrochloric acid obtained in step S12 to form a combined solution, which is transported to the anti-ferric waste hydrochloric acid receiving tank 114.

[0081] In step S15, the concentration of the concentrated ferric chloride solution is 325 g - 432 g / L.

[0082] Step two: The separation process of iron and hydrochloric acid after extraction:

[0083] Step S21: The combined solution obtained in step S15 is sprayed into the furnace of the waste hydrochloric acid fluidized bed incinerator 201, so that the hydrochloric acid and water vapor in the combined solution are vaporized. The ferric chloride in the combined solution reacts with water to form iron oxide and hydrogen chloride. The iron oxide grows into particles and is cooled and discharged by the iron oxide screw discharger 204 to obtain iron oxide products.

[0084] In step S21, the temperature of the furnace of the waste hydrochloric acid fluidized bed incinerator 201 is 800°C - 900°C.

[0085] Step S22: The hydrogen chloride + water vapor generated in step S21 is separated by a cyclone dust collector 206 to obtain a mixed gas and iron oxide dust. The iron oxide dust returns to the furnace of the waste hydrochloric acid fluidized bed incinerator 201 to be remelted and grow into particles again. The mixed gas passes through the waste heat utilization heat exchanger 207 to recover heat and obtain a cooled mixed gas.

[0086] Step S23: Spray and absorb the cooled mixed gas obtained in step S22 in the hydrochloric acid spray absorption tower 208 to obtain crude hydrochloric acid and primary tail gas; the crude hydrochloric acid is transported to the crude hydrochloric acid receiving tank 211.

[0087] Step S24: The primary tail gas obtained in step S23 is cooled by the first tail gas cooler 209 and then enters the Venturi air dissolver 210 for reabsorption to obtain hydrochloric acid and secondary tail gas. The secondary tail gas is cooled by the second tail gas cooler 212 and then discharged from the exhaust stack 213. The crude hydrochloric acid is transported to the crude hydrochloric acid receiving tank 211.

[0088] Step Three: Refining process of hydrochloric acid:

[0089] Step S31: Add the crude hydrochloric acid obtained in step two to the resin exchange tower 301, and carry out ion exchange through the resin exchange tower 301 to further remove the residual iron ions in the crude hydrochloric acid, obtaining refined hydrochloric acid and regenerated wastewater containing residual iron ions.

[0090] In step S31, the exchange resin in the resin exchange tower 301 adopts a strongly basic anion exchange resin, with an exchange capacity ≥ 3.5 mmol / g and an exchange temperature of room temperature to 45 °C.

[0091] Step S32: Finally, obtain refined hydrochloric acid and transport it to the refined hydrochloric acid collection tank 302, and then return it to the hydrochloric acid blending tank 110 for recycling.

[0092] Step S33: The regenerated wastewater containing residual iron ions is transported to the regenerated wastewater collection tank 303, and then returned to the wastewater collection and neutralization tank 115 for recycling.

[0093] In this embodiment, as Figure 1 shown, the various devices are mainly connected through the pipeline 4, and valves 5 and transfer pumps 6 are installed on the pipeline as required.

[0094] In this embodiment, the iron extraction section 101, the iron stripping section 102, and the washing section 103 all adopt the countercurrent extraction process.

[0095] In this embodiment, the iron oxide generated by the process in the wastewater collection and neutralization tank 115 is used to neutralize the acidic wastewater.

[0096] As a further solution of this embodiment, the iron ion extraction and separation device 1 further includes:

[0097] As Figures 2(a) to 2(f) shown, the raffinate outlet (10103) of the iron extraction section (101) is connected to the subsequent process.

[0098] As Figures 2(a) to 2(f) shown, the pure water feed port 10301 of the washing section 103 is connected to the pure water pipeline 111.

[0099] As shown Figures 2(a) to 2(f) in the figure, the unloading organic phase discharge port 10303 of the washing section 103 is connected to the feed port of the extractant solution tank 108 with kerosene as the solvent.

[0100] As shown Figures 2(a) to 2(f) in the figure, one inlet of the sulfate solution pH adjustment tank 104 to be extracted is connected to the sulfate solution pipeline 105 to be extracted, and the other feed port of the sulfate solution pH adjustment tank 104 to be extracted is connected to the dilute sulfuric acid pipeline 106.

[0101] As shown Figures 2(a) to 2(f) in the figure, the other feed port of the saponification tank 107 is connected to the liquid caustic soda pipeline 109.

[0102] As shown Figures 2(a) to 2(f) in the figure, the second feed port of the hydrochloric acid preparation tank 110 is connected to the pure water pipeline 111, and the third feed port of the hydrochloric acid preparation tank 110 is connected to the concentrated hydrochloric acid pipeline 112.

[0103] As a preferred solution of this embodiment, as shown Figures 2(a) to 2(f) in the figure, in the triple-effect evaporator 116, the tube-side discharge port of the first evaporator 11601 is connected to the feed port of the first vapor-liquid separator 11602. The liquid return port of the first vapor-liquid separator 11602 is connected to the tube-side feed port of the first evaporator 11601 for forced circulation. The gas-phase discharge port of the first vapor-liquid separator 11602 is connected to the shell-side feed port of the second evaporator 11603 for feeding. The other liquid-phase discharge port of the first vapor-liquid separator is connected to the tube-side feed port of the second evaporator for feeding.

[0104] The tube-side discharge port of the second evaporator 11603 is connected to the feed port of the second vapor-liquid separator 11604. The liquid return port of the second vapor-liquid separator 11604 is connected to the tube-side feed port of the second evaporator 11603. The gas-phase discharge port of the second vapor-liquid separator 11604 is connected to the shell-side feed port of the third evaporator 11605 for feeding. The other liquid-phase discharge port of the second vapor-liquid separator is connected to the tube-side feed port of the third evaporator for feeding.

[0105] The tube-side discharge port of the third evaporator 11605 is connected to the feed port of the third vapor-liquid separator 11606. The liquid return port of the third vapor-liquid separator 11606 is connected to the tube-side feed port of the third evaporator 11605 for forced circulation. The liquid discharge port of the third vapor-liquid separator 11606 is connected to the feed port of the anti-iron waste hydrochloric acid receiving tank 114.

[0106] Even more preferably, as shown Figures 2(a) to 2(f)As shown in the figure, the recovery steam pipeline 216 in the separation device 2 for iron and hydrochloric acid after extraction is connected to the shell-side steam inlet of the first evaporator 11601, and the shell-side condensate outlet of the first evaporator 11601 is connected to the recovery condensate pipeline; the gas outlet of the first vapor-liquid separator 11602 is connected to the shell-side steam inlet of the second evaporator 11603, and the shell-side condensate outlet of the second evaporator 11603 is connected to the recovery condensate pipeline; the gas outlet of the second vapor-liquid separator 11604 is connected to the shell-side steam inlet of the third evaporator 11605, and the shell-side condensate outlet of the second vapor-liquid separator 11604 is connected to the recovery condensate pipeline; the gas outlet of the third vapor-liquid separator 11606 is connected to the negative pressure pipeline.

[0107] As a further solution of this embodiment, in the separation device 2 for iron and hydrochloric acid after extraction, as Figure 3 shown, the waste hydrochloric acid fluidized bed incinerator 201 is also connected to the gas pipeline 202 and the air pipeline 203.

[0108] As a preferred solution of this embodiment, as Figure 3 shown, a cooling water pipeline 214 is provided on the iron oxide screw discharger 204. The inlet end of the cooling water pipeline 214 is connected to the softened water pipeline 215, the outlet of the cooling water pipeline 214 is connected to the shell-side inlet of the waste heat utilization heat exchanger 207, and the shell-side steam outlet of the waste heat utilization heat exchanger 207 is connected to the recovery steam pipeline 216.

[0109] As a preferred solution of this embodiment, as Figure 3 shown, a spray liquid cooler 217 is also provided on the hydrochloric acid spray absorption tower 208. The tube-side feed end of the spray liquid cooler 217 is connected to the crude hydrochloric acid receiving tank 211, the tube-side discharge end of the spray liquid cooler 217 is connected to the spray head inside the hydrochloric acid spray absorption tower 208, and the hydrochloric acid recovery port at the bottom of the hydrochloric acid spray absorption tower 208 is connected to the crude hydrochloric acid receiving tank 211 to realize circulating spray cooling absorption.

[0110] As a further solution in this embodiment, as Figure 4 shown, there are three resin exchange towers 301, which adopt a working mode of two open and one standby, and the crude hydrochloric acid generated by thermal decomposition absorption is refined by ion exchange. The connection mode of the two open resin exchange towers 301 is in series. The bottom discharge port of the first tower is connected to the top feed port of the second tower, and the bottom discharge port of the second tower is connected to the refined hydrochloric acid collection tank 302.

Claims

1. A hydrometallurgical high-iron sulfate system iron resource utilization process, characterized in that: The process includes the following steps: Step 1: Extraction process of iron ions in high iron sulfate system: Step S11, adjusting the pH value of the sulfate solution to be extracted, performing multi-stage extraction with a saponified extractant using kerosene as a solvent, extracting the iron ions in the sulfate solution to be extracted into an organic phase, obtaining a loaded organic phase, and the raffinate enters a subsequent process; Step S12, performing multi-stage stripping of the loaded organic phase obtained in step S11 with hydrochloric acid to obtain an organic phase after stripping and a ferric chloride solution containing hydrochloric acid; Step S13, washing the organic phase after the iron removal obtained in step S12 with pure water in multiple stages to obtain the unloaded organic phase and the ferric chloride waste water containing hydrochloric acid; and recovering the unloaded organic phase; Step S14, neutralizing the ferric chloride wastewater containing hydrochloric acid obtained in step S13 with the iron oxide obtained in step 2 to obtain wastewater containing ferric chloride; Step S15, concentrating the wastewater containing ferric chloride obtained in step S14 to obtain a concentrated ferric chloride solution, and combining the concentrated ferric chloride solution with the ferric chloride solution containing hydrochloric acid obtained in step S12 to form a combined solution; Step 2, separation process of iron and hydrochloric acid after extraction: Step S21, incinerating the combined liquid obtained in step S15, and allowing the ferric chloride in the combined liquid to react with water to generate ferric oxide and hydrogen chloride, and the ferric oxide to grow into particles, which are cooled and discharged to obtain an ferric oxide product; Step S22, the hydrogen chloride + water vapor generated in step S21 is separated to obtain a mixed gas and iron oxide dust, the iron oxide dust is returned to be melted again to grow into particles, and the mixed gas is subjected to heat recovery to obtain a cooled mixed gas; Step S23, spraying and absorbing the cooled mixed gas obtained in step S22 to obtain crude hydrochloric acid and primary tail gas; Step S24, the primary tail gas obtained in step S23 is cooled and then absorbed to obtain crude hydrochloric acid and secondary tail gas, and the secondary tail gas is cooled and then discharged; Step 3, refining process of hydrochloric acid: Step S31, performing ion exchange on the crude hydrochloric acid obtained in step 2 to obtain refined hydrochloric acid and regenerated wastewater containing residual iron ions; Step S32, the refined hydrochloric acid is finally returned to step 1 for recycling; Step S33, the regenerated wastewater containing residual iron ions is returned to step 1 for recycling.

2. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 1, characterized in that: The process uses an iron ion extraction and separation device (1) to perform an extraction process of iron ions in a high-ferric sulfate system; the process uses a separation device (2) for separating iron and hydrochloric acid after extraction to perform a separation process of iron and hydrochloric acid after extraction; The process uses a hydrochloric acid refining device (3) to perform a hydrochloric acid refining process; The iron ion extraction and separation device (1) comprises an extraction device with a stirring mixer and a separation chamber, wherein the extraction device with a stirring mixer and a separation chamber is divided into an iron extraction section (101), an iron removal section (102) and a washing section (103); the loaded organic phase discharge port of the iron extraction section (101) is connected to the feed port of the iron removal section (102); the iron removal organic phase discharge port of the iron removal section (102) is connected to the feed port of the washing section (103); The feed port (10101) of the iron extraction section (101) for the sulfate solution to be extracted is connected to the pH adjustment tank (104) for the sulfate solution to be extracted; the feed port (10102) of the iron extraction section (101) is connected to the discharge port of the saponification tank (107); and one feed port of the saponification tank (107) is connected to the discharge port of the extractant solution tank (108) using kerosene as solvent; The hydrochloric acid feed port (10201) of the anti-iron section (102) is connected to the discharge port of the hydrochloric acid preparation tank (110), and one feed port of the hydrochloric acid preparation tank (110) is connected to the hydrochloric acid recovery pipeline (113); the anti-iron waste hydrochloric acid discharge port (10202) of the anti-iron section (102) is connected to the feed port of the anti-iron waste hydrochloric acid receiving tank (114); The wastewater discharge port (10302) of the washing section (103) is connected to the feed port of the wastewater collection and neutralization tank (115); The iron ion extraction and separation device (1) further comprises a triple-effect evaporator (116), wherein the triple-effect evaporator (116) comprises a first evaporator (11601) and a third vapor-liquid separator (11606), wherein the tube-side feed port of the first evaporator (11601) is connected to the wastewater collecting and neutralizing tank (115) for feeding; and the liquid discharge port of the third vapor-liquid separator (11606) is connected to the feed port of the anti-iron waste hydrochloric acid receiving tank (114); The device (2) for separating iron and hydrochloric acid after extraction comprises a waste hydrochloric acid fluidized bed incinerator (201), wherein the bottom discharge port of the waste hydrochloric acid fluidized bed incinerator (201) is connected to an iron oxide spiral discharger (204), and the iron oxide spiral discharger (204) is connected to a feed port of an iron oxide silo (205); the top discharge port of the waste hydrochloric acid fluidized bed incinerator (201) is connected to a cyclone dust collector (206), the solid discharge port of the cyclone dust collector (206) is connected to the furnace of the waste hydrochloric acid fluidized bed incinerator (201), the gas outlet of the cyclone dust collector (206) is connected to the tube side air inlet of a waste heat utilization heat exchanger (207); the tube side air outlet of the waste heat utilization heat exchanger (207) is connected to the air inlet of a hydrochloric acid spray absorption tower (208); The gas outlet of the hydrochloric acid spray absorption tower (208) is connected to the pipe side inlet of the first tail gas cooler (209), the pipe side outlet of the first tail gas cooler (209) is connected to an inlet of the venturi aerator (210), the other inlet of the venturi aerator (210) is connected to the crude hydrochloric acid receiving tank (211), the outlet of the venturi aerator (210) is connected to the pipe side inlet of the second tail gas cooler (212), and the pipe side outlet of the second tail gas cooler (212) is connected to the exhaust pipe (213); The hydrochloric acid refining device (3) comprises at least one resin exchange tower (301), one discharge port of the resin exchange tower (301) is connected to a refined hydrochloric acid collection tank (302), and another discharge port of the resin exchange tower (301) is connected to a regenerated wastewater collection tank (303); The discharge port of the anti-iron waste hydrochloric acid receiving tank (114) is connected to the feed port of the waste hydrochloric acid fluidized bed incinerator (201); the crude hydrochloric acid receiving tank (211) is connected to a feed port of the resin exchange tower (301); another feed port of the resin exchange tower (301) is connected to the pure water pipeline (111); the refined hydrochloric acid collection tank (302) is connected to the recovered hydrochloric acid pipeline (113); the regenerated wastewater collection tank (303) is connected to the wastewater collection and neutralization tank (115), and the wastewater collection and neutralization tank (115) is connected to a discharge port of the iron oxide silo (205).

3. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: The process includes the following steps: Step 1: Extraction process of iron ions in high iron sulfate system: Step S11, adjusting the pH value of the sulfate solution to be extracted in the sulfate solution pH adjustment tank (104), performing multi-stage extraction in the iron extraction section (101) using a saponified extractant using kerosene as a solvent, extracting the iron ions in the sulfate solution to be extracted into an organic phase to obtain a loaded organic phase, and the raffinate enters a subsequent process; Step S12, performing multi-stage stripping of the loaded organic phase obtained in step S11 with hydrochloric acid in the anti-ferro section (102) to obtain an organic phase after anti-ferroxification and a ferric chloride solution containing hydrochloric acid; Step S13, washing the organic phase after de-ironification obtained in step S12 with pure water in the washing section (103) in multiple stages to obtain an unloaded organic phase and ferric chloride waste water containing hydrochloric acid; the unloaded organic phase is recovered to an extractant solution tank (108) using kerosene as a solvent; Step S14, neutralizing the ferric chloride wastewater containing hydrochloric acid obtained in step S13 with the iron oxide obtained in step 2 in the wastewater collection and neutralization tank (115) to obtain wastewater containing ferric chloride; Step S15, the wastewater containing ferric chloride obtained in step S14 is concentrated by the triple-effect evaporator (116) to obtain a concentrated ferric chloride solution, the concentrated ferric chloride solution is combined with the ferric chloride solution containing hydrochloric acid obtained in step S12 to form a combined liquid, and the combined liquid is transported to the anti-iron waste hydrochloric acid receiving tank (114); Step 2, separation process of iron and hydrochloric acid after extraction: Step S21, spraying the combined liquid obtained in step S15 into the furnace of the waste hydrochloric acid fluidized bed incinerator (201), so that the hydrochloric acid and water in the combined liquid are vaporized, and the ferric chloride in the combined liquid reacts with water to generate ferric oxide and hydrogen chloride, and the ferric oxide grows into particles, which are cooled and discharged through the ferric oxide spiral discharging device (204) to obtain an ferric oxide product; Step S22, the hydrogen chloride + water vapor generated in step S21 is separated into a mixed gas and iron oxide dust by a cyclone dust collector (206), the iron oxide dust is returned to the furnace of the waste hydrochloric acid fluidized bed incinerator (201) to be melted again and grown into particles, and the mixed gas is recovered by a waste heat utilization heat exchanger (207) to obtain a cooled mixed gas; Step S23, spraying and absorbing the cooled mixed gas obtained in step S22 in the hydrochloric acid spray absorption tower (208) to obtain crude hydrochloric acid and primary tail gas; the crude hydrochloric acid is transported to the crude hydrochloric acid receiving tank (211); Step S24, the primary tail gas obtained in step S23 is cooled by the first tail gas cooler (209) and then enters the venturi dissolver (210) for reabsorption to obtain hydrochloric acid and secondary tail gas, the secondary tail gas is cooled by the second tail gas cooler (212) and then discharged from the exhaust pipe (213), and the crude hydrochloric acid is transported to the crude hydrochloric acid receiving tank (211); Step 3, refining process of hydrochloric acid: Step S31, adding the crude hydrochloric acid obtained in step 2 to a resin exchange tower (301), performing ion exchange through the resin exchange tower (301), and obtaining refined hydrochloric acid and regenerated wastewater containing residual iron ions; Step S32, finally obtaining refined hydrochloric acid and conveying it to the refined hydrochloric acid collection tank (302), and then returning it to the hydrochloric acid preparation tank (110) for recycling; In step S33, the regeneration wastewater containing residual iron ions is transported to the regeneration wastewater collection tank (303), and then returned to the wastewater collection and neutralization tank (115) for recycling.

4. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 3, characterized in that: In step S11, the pH value of the sulfate solution to be extracted is adjusted to 1 to 3; In step S11, the extractant is P204 extractant or P507 extractant; the mass ratio of the extractant to kerosene is 1:(3-4); In step S11, the saponification rate of the extractant is 50-70%, and the oil-water ratio is 1:(1-3); In step S11, the number of extraction stages is 6 to 10; In step S12, the number of back extraction stages is 4 to 6; In step S13, the number of washing stages is 4 to 6; In step S14, the neutralization pH=3.5-4; In step S15, the concentration of the concentrated ferric chloride solution is 325 g to 432 g / L; In step S21, the temperature of the furnace of the waste hydrochloric acid fluidized bed incinerator (201) is 800° C. to 900° C.; In step S31, the exchange resin in the resin exchange tower (301) is a strongly basic anion exchange resin with an exchange capacity of ≥3.5 mmol / g and an exchange temperature of room temperature to 45°C.

5. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: The iron ion extraction and separation device (1) further comprises: The raffinate outlet (10103) of the iron extraction section (101) is connected to a subsequent process; The pure water feed port (10301) of the washing section (103) is connected to the pure water pipeline (111); The unloading organic phase discharge port (10303) of the washing section (103) is connected to the feed port of the extractant solution tank (108) using kerosene as solvent; One inlet of the pH adjustment tank (104) of the sulfate solution to be extracted is connected to the sulfate solution pipeline (105) to be extracted, and another feed inlet of the pH adjustment tank (104) of the sulfate solution to be extracted is connected to the dilute sulfuric acid pipeline (106); Another feed port of the saponification tank (107) is connected to a liquid alkali pipeline (109); The second feed inlet of the hydrochloric acid preparation tank (110) is connected to the pure water pipeline (111), and the third feed inlet of the hydrochloric acid preparation tank (110) is connected to the concentrated hydrochloric acid pipeline (112).

6. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: In the triple-effect evaporator (116), the tube-side discharge port of the first evaporator (11601) is connected to the feed port of the first vapor-liquid separator (11602), the liquid reflux port of the first vapor-liquid separator (11602) is connected to the tube-side feed port of the first evaporator (11601) for forced circulation, the gas phase discharge port of the first vapor-liquid separator (11602) is connected to the shell-side feed port of the second evaporator (11603) for feeding, and the other liquid phase discharge port of the first vapor-liquid separator (11602) is connected to the tube-side feed port of the second evaporator (11603) for feeding; The tube-side discharge port of the second evaporator (11603) is connected to the feed port of the second vapor-liquid separator (11604), the liquid reflux port of the second vapor-liquid separator (11604) is connected to the tube-side feed port of the second evaporator (11603) for forced circulation, the gas phase discharge port of the second vapor-liquid separator (11604) is connected to the shell-side feed port of the third evaporator (11605) for feeding, and the other liquid phase discharge port of the second vapor-liquid separator (11604) is connected to the tube-side feed port of the second evaporator (11605) for feeding; The tube-side discharge port of the third evaporator (11605) is connected to the feed port of the third vapor-liquid separator (11606), the liquid reflux port of the third vapor-liquid separator (11606) is connected to the tube-side feed port of the third evaporator (11605) for forced circulation, and the liquid discharge port of the third vapor-liquid separator (11606) is connected to the feed port of the anti-iron waste hydrochloric acid receiving tank (114).

7. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 6, characterized in that: The recovery steam pipeline (216) in the separation device (2) for separating iron and hydrochloric acid after extraction is connected to the shell-side steam inlet of the first evaporator (11601), and the shell-side condensate outlet of the first evaporator (11601) is connected to the recovery condensate pipeline; the gas outlet of the first vapor-liquid separator (11602) is connected to the shell-side steam inlet of the second evaporator (11603), and the shell-side condensate outlet of the second evaporator (11603) is connected to the recovery condensate pipeline; the gas outlet of the second vapor-liquid separator (11604) is connected to the shell-side steam inlet of the third evaporator (11605), and the shell-side condensate outlet of the second vapor-liquid separator (11604) is connected to the recovery condensate pipeline; the gas phase outlet of the third vapor-liquid separator (11606) is connected to the negative pressure pipeline.

8. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: The waste hydrochloric acid fluidized bed incinerator (201) is also connected to a gas pipeline (202) and an air pipeline (203).

9. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: The iron oxide spiral discharger (204) is provided with a cooling water pipe (214), the water inlet end of the cooling water pipe (214) is connected to the softening water pipe (215), the outlet of the cooling water pipe (214) is connected to the shell side inlet of the waste heat utilization heat exchanger (207), and the shell side steam outlet of the waste heat utilization heat exchanger (207) is connected to the recovery steam pipe (216).

10. The hydrometallurgical high-iron sulfate system iron resource utilization process according to claim 2, characterized in that: The hydrochloric acid spray absorption tower (208) is also provided with a spray liquid cooler (217), the tube side feed end of the spray liquid cooler (217) is connected to the crude hydrochloric acid receiving tank (211), the tube side discharge end of the spray liquid cooler (217) is connected to the spray head inside the hydrochloric acid spray absorption tower (208), and the hydrochloric acid recovery port at the bottom of the hydrochloric acid spray absorption tower (208) is connected to the crude hydrochloric acid receiving tank (211), so as to realize cyclic spray cold absorption.

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