Smelter acid plant based on in situ production of hydrogen sulfide from sulfur concentrates

Abstract

The utility model discloses a smeltery polluted acid equipment based on hydrogen sulfide in situ production of sulfur concentrate, include: hydrogen sulfide generating device, form with first infusion port and first feeding port, and hydrogen sulfide generating device forms with first discharge port and exhaust port, first stage solid -liquid separation device is connected in first discharge port, the sulfuration reaction device of connecting in exhaust port, and the sulfuration reaction device forms with second infusion port and second discharge port, second stage solid -liquid separation device is connected in second discharge port, neutralization reaction device, first liquid discharge port of first stage solid -liquid separation device and second stage solid -liquid separation device's second liquid discharge port are connected, and the neutralization reaction device forms with second feeding port, and the neutralization reaction device forms with third discharge port, third stage solid -liquid separation device is connected in third discharge port, and third stage solid -liquid separation device forms with third liquid discharge port and slagging port, the utility model solves smeltery polluted acid and uses the problem that the sedimentation method handles, and high cost and easy secondary pollution exist in handling.

Description

Technical Field

[0001] This utility model relates to the field of industrial wastewater treatment technology, specifically to a smelter wastewater treatment equipment based on in-situ hydrogen sulfide production from sulfur concentrate. Background Technology

[0002] Smelters generate large amounts of waste acid during non-ferrous metal smelting. This waste acid is characterized by high acidity, high concentration of heavy metal ions, and complex composition, including As. 3+ Cu2 + Pb2+, Zn2 + Cd2+, Hg2 + The discharge of various toxic and harmful heavy metal ions can cause serious pollution to the soil, water bodies, and other ecological environments, threatening human health. Therefore, efficient treatment of waste acid from smelters is a key link in the sustainable development of the non-ferrous metal smelting industry.

[0003] Currently, the main methods for removing heavy metals from waste acid in smelters include chemical precipitation, ion exchange, and adsorption. Among these, chemical precipitation is widely used due to its advantages such as simple operation, large processing capacity, and relatively low cost. Within chemical precipitation, sulfide precipitation is one of the mainstream technologies because of the extremely low solubility of heavy metal sulfides and its high removal efficiency. Traditional sulfide precipitation typically uses sodium hydrosulfide solution as a sulfiding agent, adding it to the waste acid to react with heavy metal ions and form sulfide precipitates. However, this method has significant drawbacks: firstly, sodium hydrosulfide solution is expensive (equivalent to RMB 8,500-10,000 per ton of elemental sulfur), resulting in high treatment costs. Especially for large-scale waste acid treatment, the cost of reagents becomes a heavy economic burden for enterprises. Secondly, sodium hydrosulfide is easily added in excess, and excessive sulfides, along with other forms of sulfides introduced into the water, can easily cause COD levels to exceed standards, leading to secondary pollution. Finally, the addition of sodium hydrosulfide introduces a large number of sodium ions into the wastewater, which poses a significant challenge to subsequent wastewater reuse.

[0004] Sulfur concentrate is a byproduct of non-ferrous metal sulfide ore beneficiation. It is inexpensive and widely available, and its main components are sulfides such as ferrous sulfide. Sulfur concentrate can react under acidic conditions to generate hydrogen sulfide gas, but there are currently no reports on technologies that use sulfur concentrate for the treatment of waste acid in smelters to replace sodium hydrosulfide solution by generating hydrogen sulfide in situ. Utility Model Content

[0005] To overcome the shortcomings of existing technologies, a smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate is provided to solve the problems of high treatment costs and easy secondary pollution associated with the precipitation method for treating smelter waste acid.

[0006] To achieve the above objectives, a smelter waste acid production equipment based on in-situ hydrogen sulfide production from sulfur concentrate is provided, comprising:

[0007] A hydrogen sulfide generating device, wherein the hydrogen sulfide generating device has a first liquid inlet for inputting waste acid and a first feed inlet for inputting sulfur concentrate, and the hydrogen sulfide generating device has a first discharge outlet and an exhaust outlet;

[0008] A primary solid-liquid separation device is connected to the first discharge port;

[0009] A sulfidation reaction device connected to the exhaust port, the sulfidation reaction device having a second inlet for inputting waste acid and a second outlet;

[0010] A two-stage solid-liquid separation device is connected to the second discharge port;

[0011] A neutralization reaction device is connected to the first discharge port of the primary solid-liquid separation device and the second discharge port of the secondary solid-liquid separation device. The neutralization reaction device has a second feeding port for adding lime and a third discharge port.

[0012] A three-stage solid-liquid separation device is connected to the third discharge port. The three-stage solid-liquid separation device has a third discharge port for discharging the treated liquid and a slag discharge port for discharging the precipitated solid residue.

[0013] Furthermore, the hydrogen sulfide generating device includes a reaction vessel, a stirrer installed in the reaction vessel, and a heater.

[0014] Furthermore, the exhaust port pipeline is connected to a gas pressure stabilizing tank, and the gas pressure stabilizing tank pipeline is connected to the vulcanization reaction device.

[0015] Furthermore, the vulcanization reaction device includes an aeration tank and a microporous aerator installed in the aeration tank, wherein the microporous aerator pipeline is connected to the gas pressure stabilizing tank.

[0016] Furthermore, the primary solid-liquid separation device and the secondary solid-liquid separation device are respectively provided with exhaust ports for discharging tail gas. The exhaust port pipeline is connected to a tail gas treatment device, and the tail gas treatment device is provided with a third inlet for inputting alkaline solution.

[0017] Furthermore, the slag discharge port is connected to a dehydration device, which is connected to a regulating tank for containing the waste acid via a return pipe. The regulating tank is connected to the hydrogen sulfide generator and the sulfidation reaction device via a liquid delivery pipe.

[0018] Furthermore, the dewatering device is a plate and frame filter press or a centrifugal separator.

[0019] The beneficial effects of this invention are that the smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate uses inexpensive and widely available sulfur concentrate instead of expensive sodium hydrosulfide solution as the sulfiding agent, significantly reducing reagent costs. Calculations show that the reagent cost per unit volume of waste acid treated can be reduced by 40% to 60%, significantly improving the economic benefits for enterprises.

[0020] This utility model relates to a smelter wastewater acid treatment device based on in-situ hydrogen sulfide production from sulfur concentrate. On the one hand, the hydrogen sulfide generated by the reaction of sulfur concentrate and wastewater acid is directly used for heavy metal removal, avoiding the risk of excessive COD in water bodies caused by excessive sodium hydrosulfide. On the other hand, the amount of sulfide slag generated by the reaction is reduced by 20% to 30% compared with traditional methods, and the slag has a high content of heavy metals, which facilitates resource recovery and reduces secondary pollution. Attached Figure Description

[0021] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0022] Figure 1 This is a schematic diagram of the structure of a smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate, according to an embodiment of this utility model.

[0023] Figure label:

[0024] 1. Hydrogen sulfide generator; 2. Primary solid-liquid separation unit; 3. Sulfidation reaction unit; 4. Secondary solid-liquid separation unit; 5. Neutralization reaction unit; 6. Tertiary solid-liquid separation unit; 7. Gas pressure stabilizing tank; 8. Tail gas treatment unit; 9. Regulating tank. Detailed Implementation

[0025] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant utility model and not intended to limit the scope of the utility model. Furthermore, it should be noted that, for ease of description, only the parts relevant to the utility model are shown in the accompanying drawings.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] Reference Figure 1 As shown, this utility model provides a smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate, including: a hydrogen sulfide generating device 1, a primary solid-liquid separation device 2, a sulfidation reaction device 3, a secondary solid-liquid separation device 4, a neutralization reaction device 5, and a tertiary solid-liquid separation device 6.

[0028] The hydrogen sulfide generating device 1 has a first liquid inlet and a first feed inlet.

[0029] The first inlet is for feeding waste acid. The first feed inlet is for feeding sulfur concentrate.

[0030] The hydrogen sulfide generating device 1 has a first discharge port and an exhaust port.

[0031] In a preferred embodiment, the hydrogen sulfide generating apparatus 1 includes a reaction vessel, a stirrer, and a heater. The stirrer is installed in the reaction vessel. The heater is used to regulate and control the temperature of the reactants inside the reaction vessel.

[0032] In this embodiment, the waste acid is the waste acid produced by the smelter during the non-ferrous metal smelting process, which contains As. 3 + Cu2 + Pb2+, Zn2 + Cd2+, Hg2 + One or more heavy metal ions are present in the sample, with a total concentration of heavy metal ions ranging from 100 to 5000 mg / L.

[0033] In the hydrogen sulfide generator, sulfides (taking ferrous sulfide as an example) in the sulfur concentrate react in the acidic environment of the waste acid to produce hydrogen sulfide gas. The reaction equation is: FeS + 2H₂O + =Fe 2+ +H2S↑.

[0034] The reaction conditions in the hydrogen sulfide generator are as follows: reaction temperature 30–80℃, stirring speed 100–300 r / min, reaction time 0.5–2 h, and initial pH of the waste acid 0.5–3.0. Too low a temperature results in a slow reaction rate; too high a temperature increases energy consumption and may cause premature escape of hydrogen sulfide. Too low a stirring speed leads to uneven mixing of materials; too high a stirring speed increases equipment energy consumption. Too short a reaction time results in incomplete reaction; too long a reaction time reduces processing efficiency. Maintaining the initial pH of the waste acid at 0.5–3.0 provides sufficient hydrogen ions to promote the reaction of sulfur concentrate to generate hydrogen sulfide.

[0035] In this embodiment, the particle size of the added sulfur concentrate is 100-300 mesh, with a sulfide content ≥35wt%. Too small a particle size will cause the sulfur concentrate to easily agglomerate, affecting the reaction rate; too large a particle size will result in a small reaction contact area and incomplete reaction. Controlling the sulfide content to ≥35wt% ensures the generation of sufficient hydrogen sulfide gas to meet the subsequent heavy metal removal requirements.

[0036] The solid-liquid ratio of sulfur concentrate to waste acid is 1 (g): 5–20 (mL). If the solid-liquid ratio is too low, the amount of sulfur concentrate used will be insufficient, resulting in less hydrogen sulfide generation; if the solid-liquid ratio is too high, it will lead to waste of sulfur concentrate and increase the load on subsequent processing.

[0037] The primary solid-liquid separation unit 2 is connected to the first discharge port of the hydrogen sulfide generator 1. The mixture in the reactor of the hydrogen sulfide generator 1 is discharged into the primary solid-liquid separation unit 2 through the first discharge port. The primary solid-liquid separation unit 2 separates the mixture to obtain a supernatant mainly composed of ferrous sulfate and sulfide precipitate.

[0038] The sulfidation reaction device 3 is connected to the exhaust port of the hydrogen sulfide generator 1. The sulfidation reaction device 3 also has a second liquid inlet. The second liquid inlet is used to input waste acid. The sulfidation reaction device 3 also has a second discharge port. Specifically, the hydrogen sulfide gas generated in the reactor of the hydrogen sulfide generator 1 is introduced into the waste acid to be treated in the sulfidation reaction device through the exhaust port.

[0039] In the sulfidation reactor, hydrogen sulfide gas is passed into the waste acid to be treated, where it reacts with heavy metal ions, such as Cu. 2+ +H₂S=CuS↓+2H + Pb 2 ++H2S=PbS↓+2H + ...and so on, forming insoluble sulfide precipitates.

[0040] In a preferred embodiment, the vulcanization reaction device 3 includes an aeration tank and microporous aerators. The microporous aerators are installed inside the aeration tank. The microporous aerator pipelines are connected to the gas pressure stabilizing tank 7.

[0041] In this embodiment, when hydrogen sulfide gas is introduced into the waste acid to be treated, a microporous aerator is used for microporous aeration. The aeration rate is 0.5-2 L / (L·h), the reaction temperature is 25-60℃, the reaction time is 1-3 h, and the pH of the waste acid is controlled to be 1.0-4.0 during the reaction. Microporous aeration allows hydrogen sulfide gas to be evenly dispersed in the waste acid, increasing the gas-liquid contact area and improving reaction efficiency. If the aeration rate is too low, the contact between hydrogen sulfide and heavy metal ions will be insufficient; if the aeration rate is too high, hydrogen sulfide will escape. Controlling the reaction temperature and pH ensures sufficient precipitation of heavy metal sulfides, improving the removal rate.

[0042] The secondary solid-liquid separation device 4 is connected to the second discharge port of the sulfidation reaction device 3. After sulfide precipitate is generated in the sulfidation reaction device 3, the mixed liquid in the sulfidation reaction device is discharged into the secondary solid-liquid separation device for separation to obtain supernatant and sulfide precipitate.

[0043] The neutralization reaction device 5 is connected to the first discharge port of the primary solid-liquid separation device 2 and the second discharge port of the secondary solid-liquid separation device 4. The neutralization reaction device 5 also has a second feed port for feeding lime. The neutralization reaction device 5 also has a third discharge port.

[0044] In the neutralization reaction apparatus, the supernatant obtained from the primary solid-liquid separation device and the secondary solid-liquid separation device is discharged together and lime is added to carry out the neutralization reaction.

[0045] The three-stage solid-liquid separation device 6 is connected to the third discharge port. The three-stage solid-liquid separation device 6 has a third discharge port for discharging the treated liquid and a slag discharge port for discharging the precipitated solid slag.

[0046] The mixture obtained from the neutralization reaction in the neutralization reactor is separated into supernatant and lime-iron salt neutralization precipitate solid residue by a three-stage solid-liquid separation device. At this point, if the supernatant meets the standards, it is discharged or enters subsequent advanced treatment processes.

[0047] In a preferred embodiment, the slag discharge port of the three-stage solid-liquid separation device is connected to a dewatering device. The dewatering device is connected to a regulating tank 9 via a return pipe. The regulating tank 9 is used to hold the waste acid. The regulating tank 9 is connected to the hydrogen sulfide generator 1 and the sulfidation reaction device 3 via liquid delivery pipes.

[0048] The dewatering device is a plate and frame filter press or a centrifugal separator.

[0049] In this embodiment, the primary solid-liquid separation device 2, the secondary solid-liquid separation device 4, and the tertiary solid-liquid separation device 6 can be thickeners or high-efficiency sedimentation tanks.

[0050] The sludge produced by the primary solid-liquid separation unit 2, the secondary solid-liquid separation unit 4, and the tertiary solid-liquid separation unit 6 is dewatered by a plate and frame filter press or a centrifuge. The separated sulfide precipitate or iron salt lime neutralization precipitate is then recycled or safely disposed of.

[0051] Plate and frame filter presses and centrifugal separators have the advantages of high separation efficiency and simple operation. The sulfide precipitates obtained by separation have a high content of heavy metals, which can be recycled through further processing. If recycling is not possible, they can be safely landfilled.

[0052] In a preferred embodiment, the exhaust port pipe is connected to a gas pressure stabilizing tank 7. The gas pressure stabilizing tank 7 is connected to a vulcanization reaction device 3. The gas pressure stabilizing tank is a gravity floating type gas pressure stabilizing tank, using nitrogen as the carrier gas.

[0053] The primary solid-liquid separation device 2 and the secondary solid-liquid separation device 4 each have exhaust ports for discharging tail gas. The exhaust port pipes are connected to a tail gas treatment device 8. The tail gas treatment device 8 has a third inlet for inputting alkaline solution. A reaction chamber is formed within the tail gas treatment device 8. The reaction chamber of the tail gas treatment device 8 is filled with alkaline solution to absorb any uncollected hydrogen sulfide gas. The alkaline solution can be sodium hydroxide solution or calcium hydroxide solution with a concentration of 5–15 wt%, which can effectively absorb leaked hydrogen sulfide gas, avoiding environmental pollution and safety risks.

[0054] The present invention relates to a smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate, comprising, in sequence, a waste acid regulating tank, a hydrogen sulfide generating device, a gas stabilizing tank and conveying pipeline, a sulfidation reaction device, a primary solid-liquid separation device, a secondary solid-liquid separation device, a tertiary solid-liquid separation device, and a tail gas treatment unit.

[0055] This invention relates to a smelter waste acid treatment device based on in-situ hydrogen sulfide production from sulfur concentrate. It utilizes inexpensive and widely available sulfur concentrate instead of expensive sodium hydrosulfide solution as the sulfiding agent, significantly reducing reagent costs. Calculations show that the reagent cost per unit volume of waste acid treated can be reduced by 40%-60%, significantly improving the economic benefits for enterprises.

[0056] This utility model relates to a smelter wastewater acid treatment device based on in-situ hydrogen sulfide production from sulfur concentrate. On the one hand, the hydrogen sulfide generated by the reaction of sulfur concentrate and wastewater acid is directly used for heavy metal removal, avoiding the risk of excessive COD in water bodies caused by excessive sodium hydrosulfide. On the other hand, the amount of sulfide slag generated by the reaction is reduced by 20% to 30% compared with traditional methods, and the slag has a high content of heavy metals, which facilitates resource recovery and reduces secondary pollution.

[0057] This invention relates to a smelter waste acid production equipment based on in-situ hydrogen sulfide production from sulfur concentrate. The equipment utilizes microporous aeration to ensure sufficient contact between hydrogen sulfide and waste acid, effectively controlling As3+ and Cu2+. + Pb 2 +、Zn2 + Cd 2 +、Hg2 + The removal rate of heavy metal ions can reach over 99%, and the concentration of heavy metal ions in the treated supernatant is far below the national emission standards.

[0058] This utility model's smelter waste acid equipment, based on in-situ hydrogen sulfide production from sulfur concentrate, requires no complex equipment and is easy to operate and control. The hydrogen sulfide is contained within a sealed space and protected by a slight positive pressure of nitrogen to prevent air ingress. Simultaneously, the tail gas treatment device in the solid-liquid separation unit (primary and secondary solid-liquid separation units) effectively absorbs leaked hydrogen sulfide gas, reducing safety hazards and improving process safety.

[0059] This utility model provides a method for treating waste acid from smelters based on in-situ hydrogen sulfide production from sulfur concentrate, comprising the following steps:

[0060] Step (1): Introduce the waste acid from the smelter into the hydrogen sulfide generator, add sulfur concentrate into the hydrogen sulfide generator, control the reaction conditions, and make the sulfur concentrate react with the waste acid to generate hydrogen sulfide gas.

[0061] The sulfur concentrate has a particle size of 100–300 mesh, with a sulfide content ≥35 wt%. The sulfide content is controlled to be ≥35 wt%.

[0062] The solid-liquid ratio of sulfur concentrate to waste acid is 1:5 to 20 (g:mL).

[0063] The reaction temperature is 30–80℃, the stirring rate is 100–300 r / min, the reaction time is 0.5–2 h, and the initial pH of the waste acid is 0.5–3.0.

[0064] The initial pH value of the waste acid is controlled at 0.5-3.0, which can provide sufficient hydrogen ions to promote the reaction of sulfur concentrate to generate hydrogen sulfide.

[0065] The hydrogen sulfide generator is equipped with a gas collection and pressure stabilization unit, which collects hydrogen sulfide gas. A primary solid-liquid separation unit and a secondary solid-liquid separation unit are connected to a tail gas treatment unit. The alkaline solution in the tail gas treatment unit absorbs any uncollected hydrogen sulfide gas. The alkaline solution can be sodium hydroxide or calcium hydroxide solution with a concentration of 5–15 wt%, which can effectively absorb leaked hydrogen sulfide gas, avoiding environmental pollution and safety risks.

[0066] Step (2): After collecting the hydrogen sulfide gas generated in step (1), it is passed into a sulfidation reaction device containing the waste acid to be treated, so that the hydrogen sulfide reacts with the heavy metal ions in the waste acid to generate sulfide precipitates.

[0067] In step (2), when hydrogen sulfide gas is introduced into the waste acid to be treated, microporous aeration is used, the aeration rate is 0.5 to 2 L / (L·h), the reaction temperature is 25 to 60℃, the reaction time is 1 to 3 h, and the pH value of the waste acid is controlled to be 1.0 to 4.0 during the reaction.

[0068] Step (3): The mixture after the reaction in step (2) is introduced into a secondary solid-liquid separation device to separate the supernatant and sulfide precipitate. The supernatant and the supernatant from the first solid-liquid separation device enter the neutralization reaction device (lime is added). The mixture enters the third solid-liquid separation device. The supernatant is discharged in compliance with the standard or enters the subsequent deep treatment process. At the same time, lime iron salt neutralization precipitate solid slag is obtained.

[0069] To further illustrate the heavy metal removal effect of the smelter waste acid treatment method based on in-situ hydrogen sulfide production from sulfur concentrate, the following examples are provided for detailed explanation.

[0070] Example 1

[0071] The smelter waste acid treated in this embodiment contains Cu. 2+ Zn 2+ Cu 2+ Concentration of 800 mg / L, Zn 2+ The concentration was 1200 mg / L, and the initial pH of the waste acid was 1.5.

[0072] The present invention provides a method for treating waste acid from smelters based on in-situ hydrogen sulfide production from sulfur concentrate, comprising the following steps:

[0073] (1) The waste acid is introduced into the reactor of the hydrogen sulfide generator. Sulfur concentrate with a particle size of 200 mesh (sulfide content of 75wt%) is added through the first feed port. The solid-liquid ratio of sulfur concentrate to waste acid is controlled at 1:10 (g:mL). The stirrer is turned on and the stirring speed is 200r / min. The reaction temperature is controlled at 50℃ through the heater and the reaction time is 1h. The sulfur concentrate reacts with the waste acid to generate hydrogen sulfide gas. The hydrogen sulfide gas is collected through the gas pressure stabilizing tank. The hydrogen sulfide gas that escapes from the solid-liquid separation device enters the tail gas treatment unit and is absorbed by 10wt% sodium hydroxide solution.

[0074] (2) The collected hydrogen sulfide gas is sent through a gas pipeline into the aeration tank of the sulfidation reaction device containing the waste acid to be treated. Microporous aeration is used at a rate of 1 L / (L·h), and the reaction temperature is controlled at 40℃. During the reaction, the pH of the waste acid is adjusted to 2.5 by adding acid. The reaction time is 2 hours. The hydrogen sulfide reacts with the Cu in the waste acid... 2+ Zn 2+ The reaction produces sulfide precipitates.

[0075] (3) The mixture after reaction is sent to a plate and frame filter press for solid-liquid separation to obtain supernatant and sulfide precipitate.

[0076] Tests showed that Cu in the supernatant 2+ The concentration is 0.5 mg / L, Zn 2+ The concentration was 0.8 mg / L, which met the "Emission Standard of Pollutants for Copper, Nickel and Cobalt Industry" (GB25467-2010). The Cu and Zn contents in the sulfide precipitate were 35 wt% and 42 wt%, respectively, and can be recycled.

[0077] Example 2

[0078] The smelter waste acid treated in this embodiment contains Pb. 2 +、Cd 2 +、Hg 2+ Pb 2 + Concentration of 500 mg / L, Cd 2 +Concentration is 100 mg / L, Hg 2+ The concentration was 5 mg / L, and the initial pH of the waste acid was 0.8.

[0079] The present invention provides a method for treating waste acid from smelters based on in-situ hydrogen sulfide production from sulfur concentrate, comprising the following steps:

[0080] (1) The above-mentioned waste acid is introduced into the reactor of the hydrogen sulfide generator. Sulfur concentrate with a particle size of 150 mesh (sulfide content of 65wt%) is added through the first feed port. The solid-liquid ratio of sulfur concentrate to waste acid is controlled at 1:8 (g:mL). The stirrer is turned on and the stirring speed is 250r / min. The reaction temperature is controlled at 60℃ through the heater and the reaction time is 0.8h. The sulfur concentrate and waste acid react to generate hydrogen sulfide gas. The hydrogen sulfide gas is collected through the gas collection and stabilization unit. The hydrogen sulfide gas that escapes from the solid-liquid separation device enters the tail gas treatment unit and is absorbed by 8wt% calcium hydroxide solution.

[0081] (2) The collected hydrogen sulfide gas is sent through a gas pipeline into the aeration tank of the sulfidation reaction device containing the waste acid to be treated. Microporous aeration is used, with an aeration rate of 1.5 L / (L·h). The reaction temperature is controlled at 50℃. During the reaction, the pH of the waste acid is adjusted to 1.8 by adding acid. The reaction time is 1.5 h. The hydrogen sulfide reacts with As in the waste acid... 3+ Pb2+, Cd2+, Hg2 + The reaction produces sulfide precipitates.

[0082] (3) The mixture after reaction is sent to a centrifuge for solid-liquid separation to obtain supernatant and sulfide precipitate.

[0083] Tests showed that As was present in the supernatant. 3+ The concentrations were 0.05 mg / L for Pb²⁺, 0.3 mg / L for Cd²⁺, and 0.05 mg / L for Hg. 2+ The concentration was 0.001 mg / L, which complied with the "Emission Standard of Pollutants for Copper, Nickel and Cobalt Industries" (GB25467-2010). The sulfide precipitate was disposed of safely by landfill.

[0084] Comparative Example 1

[0085] The smelter waste acid, which was treated with the same sodium hydrosulfide solution as in Example 1, was treated using conventional sodium hydrosulfide solution. The amount of sodium hydrosulfide solution added was controlled to be 1.2 times the theoretical amount, and other reaction conditions were the same as in Example 1.

[0086] Tests showed that Cu in the supernatant 2+ The concentration is 0.6 mg / L, Zn 2+ The concentration was 0.9 mg / L, the reagent cost for treating a unit volume of waste acid was 2.3 times that of Example 1, and the amount of sulfide slag produced was 1.25 times that of Example 1.

[0087] As can be seen from Examples 1 and 2 and Comparative Example 1, the smelter waste acid treatment method based on in-situ hydrogen sulfide production from sulfur concentrate of this invention significantly reduces treatment costs and reduces the amount of sulfide slag generated while ensuring the removal effect of heavy metals, and has obvious advantages.

[0088] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A smelter waste acid production equipment based on in-situ hydrogen sulfide production from sulfur concentrate, characterized in that, include: A hydrogen sulfide generating device, wherein the hydrogen sulfide generating device has a first liquid inlet for inputting waste acid and a first feed inlet for inputting sulfur concentrate, and the hydrogen sulfide generating device has a first discharge outlet and an exhaust outlet; A primary solid-liquid separation device is connected to the first discharge port; A sulfidation reaction device connected to the exhaust port, the sulfidation reaction device having a second inlet for inputting waste acid and a second outlet; A two-stage solid-liquid separation device is connected to the second discharge port; A neutralization reaction device is connected to the first discharge port of the primary solid-liquid separation device and the second discharge port of the secondary solid-liquid separation device. The neutralization reaction device has a second feeding port for adding lime and a third discharge port. A three-stage solid-liquid separation device is connected to the third discharge port. The three-stage solid-liquid separation device has a third discharge port for discharging the treated liquid and a slag discharge port for discharging the precipitated solid residue.

2. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 1, characterized in that, The hydrogen sulfide generating device includes a reaction vessel, a stirrer installed in the reaction vessel, and a heater.

3. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 1, characterized in that, The exhaust port pipeline is connected to a gas pressure stabilizing tank, and the gas pressure stabilizing tank pipeline is connected to the vulcanization reaction device.

4. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 3, characterized in that, The vulcanization reaction device includes an aeration tank and a microporous aerator installed in the aeration tank, and the pipeline of the microporous aerator is connected to the gas pressure stabilizing tank.

5. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 1, characterized in that, The primary solid-liquid separation device and the secondary solid-liquid separation device are respectively provided with exhaust ports for discharging tail gas. The exhaust port pipeline is connected to a tail gas treatment device, and the tail gas treatment device is provided with a third inlet for inputting alkaline solution.

6. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 1, characterized in that, The slag discharge port is connected to a dehydration device, which is connected to a regulating tank for containing the waste acid via a return pipe. The regulating tank is connected to the hydrogen sulfide generator and the sulfidation reaction device via a liquid delivery pipe.

7. The smelter waste acid equipment based on in-situ hydrogen sulfide production from sulfur concentrate according to claim 6, characterized in that, The dehydration device is a plate and frame filter press or a centrifugal separator.

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