Lithium sulfide production device, lithium sulfide production equipment, and method for producing lithium sulfide

Abstract

Provided is a device for producing lithium sulfide, the lithium sulfide production device being equipped with a reactor 1 for reacting hydrogen sulfide with a lithium source. The reactor 1 has a hydrogen sulfide inlet line 4 for introducing hydrogen sulfide obtained from a desulfurizer 2 into the reactor 1 and a hydrogen sulfide outlet line 5 for releasing unreacted hydrogen sulfide to the outside of the reactor.

Description

Lithium sulfide manufacturing apparatus, lithium sulfide manufacturing facility, and lithium sulfide manufacturing method

[0001] The present invention relates to an apparatus for producing lithium sulfide, a facility for producing lithium sulfide, and a method for producing lithium sulfide.

[0002] Solid electrolytes have been attracting attention as electrolytes for lithium-ion secondary batteries. Solid electrolytes are used in all-solid-state batteries and are expected to contribute to improving the safety and performance of secondary batteries. Examples of solid electrolytes include sulfide solid electrolytes (see, for example, Patent Document 1). Lithium sulfide is used as a raw material for sulfide solid electrolytes.

[0003] JP 2010-163356 A

[0004] Although Patent Document 1 discloses a method for producing lithium sulfide, further expansion of production is required as a supply source of lithium sulfide. Up until now, no sufficient study has been made on an industrially efficient method for producing lithium sulfide.

[0005] Therefore, an object of the present invention is to provide a lithium sulfide production apparatus, a lithium sulfide production facility, and a lithium sulfide production method, which produce lithium sulfide from hydrogen sulfide obtained by an existing desulfurization apparatus.

[0006] One embodiment of the present invention relates to an apparatus for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with a lithium source; a hydrogen sulfide inlet line through which hydrogen sulfide obtained from a desulfurization apparatus is introduced into the reactor; and a hydrogen sulfide outlet line through which unreacted hydrogen sulfide is released to the outside of the reactor.

[0007] One embodiment of the present invention relates to a facility for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with lithium hydroxide; a desulfurization device; a sulfur recovery device; a hydrogen sulfide inlet line through which hydrogen sulfide obtained from the desulfurization device is introduced into the reactor; and a hydrogen sulfide outlet line through which unreacted hydrogen sulfide is released from the reactor and introduced into the sulfur recovery device.

[0008] One embodiment of the present invention relates to a method for producing lithium sulfide, comprising: introducing hydrogen sulfide obtained from a desulfurization apparatus into the reactor; reacting the hydrogen sulfide with lithium hydroxide; and releasing unreacted hydrogen sulfide to the outside of the reactor and introducing the unreacted hydrogen sulfide into a sulfur recovery apparatus.

[0009] According to the present invention, it is possible to provide an apparatus for producing lithium sulfide, a facility for producing lithium sulfide, and a method for producing lithium sulfide, which produce lithium sulfide from hydrogen sulfide obtained by an existing desulfurization apparatus.

[0010] Fig. 1 is a block diagram showing a schematic configuration of a lithium sulfide production facility, Fig. 2 is a schematic diagram of a lithium sulfide production facility, and Fig. 3 is a schematic diagram of a desulfurization device.

[0011] Hereinafter, an embodiment of the present invention (hereinafter also referred to as the present embodiment) will be described. In this specification, for example, when a numerical range is expressed as "1 to 100," it is assumed that the range includes both the lower limit "1" and the upper limit "100." The same applies to other numerical ranges.

[0012] The present embodiment relates to an apparatus for producing lithium sulfide, the apparatus comprising: a reactor for reacting hydrogen sulfide with a lithium source; a hydrogen sulfide inlet line for introducing hydrogen sulfide obtained from a desulfurization apparatus into the reactor; and a hydrogen sulfide outlet line for discharging unreacted hydrogen sulfide to the outside of the reactor. According to the present embodiment, it is possible to provide an apparatus for producing lithium sulfide from hydrogen sulfide obtained by an existing desulfurization apparatus. Existing desulfurization apparatuses are installed, for example, in petroleum product refineries and are devices for removing sulfur components from products. Hydrogen sulfide is generated during this desulfurization, and this hydrogen sulfide is commercialized as sulfur in a sulfur recovery apparatus. By effectively utilizing the hydrogen sulfide obtained in the desulfurization apparatus as a raw material for lithium sulfide, lithium sulfide, which has higher added value than sulfur, can be efficiently produced without requiring energy or the like for the production of hydrogen sulfide.

[0013] The present embodiment may also be an apparatus for producing lithium sulfide, the apparatus comprising a reactor for reacting hydrogen sulfide with a lithium source, the reactor being connectable to a hydrogen sulfide inlet line through which hydrogen sulfide obtained from a desulfurization apparatus is introduced into the reactor, and a hydrogen sulfide outlet line through which unreacted hydrogen sulfide is released to the outside of the reactor.

[0014] The "lithium source" refers to a lithium raw material that reacts with hydrogen sulfide to produce lithium sulfide. Examples of lithium sources include metallic lithium, lithium sulfate, lithium hydroxide, lithium carbonate, and lithium oxide. Among these, lithium hydroxide and lithium carbonate are preferred, and lithium hydroxide is more preferred.

[0015] "Hydrogen sulfide" has the chemical formula H ２ S. "Gaseous hydrogen sulfide" is a compound with the chemical formula H ２ The hydrogen sulfide introduced into the reactor may contain other components.

[0016] The hydrogen sulfide introduced into the reactor preferably has a water content of 20 vol% or less, more preferably 10 vol% or less, and even more preferably 5 vol% or less, based on the hydrogen sulfide.

[0017] The temperature of the hydrogen sulfide introduced into the reactor may be 100 to 300°C, 150 to 250°C, or 180 to 220°C. In the reactor according to this embodiment, even at these temperatures, the hydrogen sulfide can be introduced into the reactor without being cooled. The hydrogen sulfide introduced into the reactor may contain moisture equivalent to the amount of saturated water vapor at that temperature. In the reaction in the reactor according to this embodiment, the hydrogen sulfide can be introduced into the reactor without removing the moisture from it, which can reduce the operating energy consumption of the entire facility.

[0018] The amount of hydrogen sulfide introduced from the hydrogen sulfide inlet line is preferably 0.05 mol% / h or more, more preferably 0.08 mol% / h or more and 0.30 mol% / h or less, and even more preferably 0.10 mol% / h or more and 0.20 mol% / h or less, per mol of lithium source. By introducing hydrogen sulfide into the reactor within such a range, unreacted hydrogen sulfide is released outside the reactor and water is also discharged, allowing the reaction to proceed efficiently within the reactor.

[0019] In the reactor, hydrogen sulfide reacts with a lithium source. The lithium source is lithium hydroxide (LiOH) and lithium carbonate (Li ２ CO ３ When using 2LiOH + H, the following reaction occurs: ２ S → Li ２ S + 2H ２ O Li ２ CO ３ + H ２ S → Li ２ S + H ２ O + CO ２

[0020] The reactor may be any device capable of contacting hydrogen sulfide with a lithium source. The reactor may be a fixed-bed, moving-bed, tumbling-bed, or fluidized-bed reactor. The reactor is preferably a device capable of contacting gaseous hydrogen sulfide with a powdered lithium source. In this case, the reactor may be a powder dryer, as long as it can bring a gas and a solid into contact and cause a reaction. A conductive heat transfer dryer such as a disk dryer is preferably used as the powder dryer. Examples of disk dryers include those with the product names "Micron Thermoprocessor" and "Torus Disk" (manufactured by Hosokawa Micron Corporation), "Paddle Dryer" (manufactured by Nara Machinery Works, Ltd.), "Inclined Disk Dryer" (manufactured by Tsukishima Holdings Co., Ltd.), and CD dryer. The reaction between hydrogen sulfide and a lithium source produces lithium sulfide, which also produces water. The reaction between lithium sulfide and water can also produce lithium hydroxide. By using a dryer to carry out the gas-solid reaction of hydrogen sulfide and lithium hydroxide, a larger amount of water produced during the reaction can be released outside the reactor, the equilibrium reaction can proceed in favor of the production of lithium sulfide, and lithium sulfide can be obtained in a higher yield. When a dryer is used as the reactor, the lithium source introduced into the reactor does not need to be in powder form from the beginning, as long as it can be converted into powder in the dryer.

[0021] The reactor preferably has a mechanism for fluidizing the powder. Fluidizing the powder in the reactor increases the contact efficiency between the powdered lithium source in the reactor and the gaseous hydrogen sulfide, and also facilitates drying of the powder, allowing more water to be released outside the reactor, thereby improving the reaction yield. Examples of the mechanism for fluidizing the powder include a disk.

[0022] A "desulfurization device" is a device that removes compounds containing sulfur element from an object and may generate hydrogen sulfide. The desulfurization device is preferably a hydrodesulfurization device. Since the desulfurization device is capable of procuring large amounts of hydrogen sulfide, it may be a desulfurization device used in an oil refinery or a natural gas refining facility. Examples of desulfurization devices include lubricating oil desulfurization devices, vacuum diesel desulfurization devices, kerosene desulfurization devices, gas recovery desulfurization devices, and heavy oil desulfurization devices.

[0023] The desulfurization unit may have a hydrogen sulfide treatment unit that uses a liquid composition containing water, and hydrogen sulfide treated by the hydrogen sulfide treatment unit may be introduced into the hydrogen sulfide inlet line. This configuration not only allows hydrogen sulfide to be treated and its purity to be increased, but also allows the water in the hydrogen sulfide to have little effect on the reaction in the reactor according to this embodiment, so that the hydrogen sulfide can be introduced into the reactor without treatment such as water removal, thereby reducing the operating energy consumption of the entire facility.

[0024] Examples of hydrogen sulfide treatment devices include a separation and recovery device that separates and recovers hydrogen and hydrogen sulfide, and a water washing device that washes hydrogen sulfide with water.

[0025] When the desulfurization apparatus is a hydrodesulfurization apparatus, the desulfurization apparatus may include a separation and recovery apparatus that separates and recovers hydrogen and hydrogen sulfide as the hydrogen sulfide treatment apparatus described above. The separation and recovery apparatus may be a dry type or a wet type, but a wet type separation and recovery apparatus is preferably used. Furthermore, the separation and recovery apparatus is preferably an amine treatment apparatus. A wet type separation and recovery apparatus preferably includes an aqueous solution of an amine, such as ethanolamine or diethanolamine, as an absorbent. A wet type separation and recovery apparatus chemically adsorbs hydrogen sulfide by contacting an aqueous amine solution with a gas containing hydrogen and hydrogen sulfide, and separates it from the hydrogen. The chemically adsorbed hydrogen sulfide is desorbed under high-temperature conditions, thereby obtaining gaseous hydrogen sulfide. With the lithium sulfide production apparatus according to this embodiment, the reaction proceeds without significantly impairing the reaction yield even with hydrogen sulfide containing a large amount of water. Therefore, lithium sulfide can be synthesized with a high yield even using hydrogen sulfide obtained from a desulfurization apparatus that uses a separation and recovery apparatus that uses an aqueous amine solution as an absorbent.

[0026] The "desulfurization recovery device" is a device that processes hydrogen sulfide to recover sulfur content. The desulfurization recovery device may be, for example, a device that recovers hydrogen sulfide as elemental sulfur by the Claus reaction. In the desulfurization recovery device, hydrogen sulfide (H ２ S) decomposes to form sulfur dioxide (SO ２ ), which is then oxidized to elemental sulfur (S) and water by the Claus reaction of hydrogen sulfide with sulfur dioxide in the presence of a catalyst. Examples of catalysts include natural bauxite, activated alumina, and titanium dioxide.

[0027] In this specification, the term "line" refers to a system for supplying a gas or a solid. A typical example of a system for supplying a gas or a solid is piping.

[0028] The "hydrogen sulfide inlet line" refers to a conduit for introducing hydrogen sulfide into the reactor. For example, it may be a pipe connecting the hydrogen sulfide outlet of the desulfurization device and the hydrogen sulfide inlet of the reactor.

[0029] The "hydrogen sulfide outlet line" is a conduit for discharging hydrogen sulfide to the outside of the reactor. For example, it may be a pipe connecting the hydrogen sulfide outlet of the reactor to the hydrogen sulfide inlet of the sulfur recovery device.

[0030] In the reactor, hydrogen sulfide and a lithium source may be reacted at a high temperature. Therefore, the hydrogen sulfide discharged from the reactor may be at a high temperature due to heating within the reactor. Furthermore, since water is generated by the reaction between hydrogen sulfide and a lithium source (e.g., lithium hydroxide), the discharged hydrogen sulfide contains a large amount of moisture. If hydrogen sulfide in such a state is introduced directly into a sulfur recovery device, it may adversely affect the reaction in the sulfur production process, resulting in a decrease in sulfur production volume, a deterioration in sulfur quality, and the like. Furthermore, high-temperature hydrogen sulfide containing moisture may condense due to heat release in the gas supply piping, and if it stagnates, it becomes a corrosive environment, which is undesirable.

[0031] The temperature of the hydrogen sulfide released from the reactor to the hydrogen sulfide outlet line is preferably 150° C. or higher, more preferably 150° C. or higher and 300° C. or lower, and even more preferably 150° C. or higher and 250° C. or lower. By setting the temperature at such a range, water generated by the reaction is more likely to be released outside the reactor together with unreacted hydrogen sulfide, and the reaction proceeds smoothly.

[0032] Therefore, it is preferable to provide a cooling device in the hydrogen sulfide outlet line to cool the hydrogen sulfide discharged from the reactor. By providing a cooling device, the temperature can be lowered, thereby reducing corrosion of the device. Furthermore, by lowering the temperature using a cooling device, gaseous water contained in the hydrogen sulfide condenses and a liquid is generated. For this reason, by providing a gas-liquid separator as a moisture removal device (described later) downstream of the cooling device, moisture can be efficiently removed. From another perspective, since lowering the temperature using a cooling device can cause gaseous water contained in the hydrogen sulfide to condense and a large amount of liquid to be generated, the moisture removal device (described later) may be provided closer to the reactor than the cooling device.

[0033] Examples of the cooling device include an air-cooled heat exchanger, a water-cooled heat exchanger, and a cooling water circulator.

[0034] The cooling device preferably reduces the temperature of hydrogen sulfide by 10°C or more, more preferably by 50°C or more, even more preferably by 100°C or more, and even more preferably by 150°C or more.

[0035] As described above, since the hydrogen sulfide discharged from the reactor contains a large amount of water, it is preferable to provide a water removal device in the hydrogen sulfide outlet line for removing water from the hydrogen sulfide. The water removal device may be any device capable of removing at least a portion of the water in the gas, and may be, for example, a gas-liquid separator.

[0036] The hydrogen sulfide outlet line may be provided with a cooling device for cooling the hydrogen sulfide discharged from the reactor. The hydrogen sulfide discharged from the reactor may be at a high temperature due to heating within the reactor. Lowering the temperature with the cooling device may cause the gaseous water contained in the hydrogen sulfide to condense, generating a large amount of liquid. Therefore, it is preferable to provide the moisture removal device described above on the reactor side rather than the cooling device.

[0037] The lithium sulfide manufacturing apparatus according to the present embodiment is preferably configured so that unreacted hydrogen sulfide is introduced into the sulfur recovery apparatus through the hydrogen sulfide outlet line. In the reactor, gaseous hydrogen sulfide is reacted with the powdered lithium source, and by introducing the unreacted hydrogen sulfide into the sulfur recovery apparatus through the hydrogen sulfide outlet line, hydrogen sulfide can be safely treated.

[0038] The lithium sulfide manufacturing apparatus according to this embodiment is preferably configured to further include a dryer for drying the lithium source, and to introduce the lithium source dried by the dryer into the reactor. By including the dryer in the lithium sulfide manufacturing apparatus and drying the lithium source before introducing it into the reactor, moisture contained in the lithium source can be removed, and the lithium source can be processed into powder in the reactor, allowing the reaction with gaseous hydrogen sulfide to proceed smoothly. Note that when lithium hydroxide is used as the lithium source, the lithium sulfide manufacturing apparatus is preferably equipped with the dryer.

[0039] The present embodiment relates to a lithium sulfide production facility comprising: a reactor for reacting hydrogen sulfide with lithium hydroxide, a desulfurization device, a sulfur recovery device, a hydrogen sulfide inlet line for introducing hydrogen sulfide obtained from the desulfurization device into the reactor, and a hydrogen sulfide outlet line for releasing unreacted hydrogen sulfide to the outside of the reactor and introducing it into the sulfur recovery device. According to the present embodiment, it is possible to provide a lithium sulfide production facility for producing lithium sulfide from hydrogen sulfide obtained by an existing desulfurization device.

[0040] The desulfurization device in the lithium sulfide manufacturing facility according to this embodiment may be configured to include a hydrogen sulfide treatment device that uses a liquid composition containing water, and to introduce hydrogen sulfide treated by the hydrogen sulfide treatment device into the hydrogen sulfide inlet line. The hydrogen sulfide treatment device is as described above.

[0041] The lithium sulfide production facility according to this embodiment preferably includes a bypass line for supplying hydrogen sulfide directly from the desulfurization device to the sulfur recovery device. The "bypass line" is a conduit for supplying hydrogen sulfide from the desulfurization device to the sulfur recovery device without passing through the reactor. By including the bypass line, even if the reactor is a batch-type reactor, hydrogen sulfide continuously produced in the desulfurization device can be safely introduced into the sulfur recovery device while a new batch of lithium source is being introduced into the reactor or when the introduction of hydrogen sulfide into the reactor is stopped, for example, during reactor maintenance or inspection.

[0042] The present embodiment relates to a method for producing lithium sulfide, comprising: introducing hydrogen sulfide obtained from a desulfurization apparatus into a reactor; reacting the hydrogen sulfide with lithium hydroxide in the reactor; and releasing unreacted hydrogen sulfide to the outside of the reactor and introducing it into a sulfur recovery apparatus. According to the present embodiment, it is possible to provide a method for producing lithium sulfide from hydrogen sulfide obtained by an existing desulfurization apparatus.

[0043] The method for producing lithium sulfide according to this embodiment can be carried out using the lithium sulfide production facility according to the embodiment described above. The lithium source, the amount of water in the introduced hydrogen sulfide, the temperature, the reactor, the desulfurization device, and the sulfur recovery device used in the method for producing lithium sulfide according to this embodiment are as described above.

[0044] The temperature inside the reactor may be 100 to 300°C, 150 to 250°C, or 180 to 220°C.

[0045] When unreacted hydrogen sulfide is discharged to the outside of the reactor, it is preferable to discharge water generated during the reaction to the outside of the reactor.

[0046] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings, but the present invention is not limited thereto. In the drawings, the same elements are given the same reference numerals and redundant explanations will be omitted.

[0047] Hereinafter, a lithium sulfide production facility using the lithium sulfide production apparatus according to this embodiment will be described in more detail. FIG. 1 is a block diagram showing a schematic configuration of the lithium sulfide production facility. As shown in FIG. 1, the lithium sulfide production facility according to this embodiment includes a reactor 1, a desulfurization device 2, and a sulfur recovery device 3. The reactor 1 is connected to a lithium source supply line 11, and a lithium source is introduced into the reactor 1. The lithium sulfide production facility according to this embodiment includes a hydrogen sulfide inlet line 4 through which hydrogen sulfide obtained from the desulfurization device 2 is introduced into the reactor 1, and a hydrogen sulfide outlet line 5 through which unreacted hydrogen sulfide is released out of the reactor 1 and introduced into the sulfur recovery device 3. Hydrogen sulfide is introduced into the reactor 1 through the hydrogen sulfide inlet line 4 and reacts with the lithium source, and unreacted hydrogen sulfide and produced water are released through the hydrogen sulfide outlet line 5. The lithium sulfide obtained in the reactor 1 is sent out of the reactor 1 through a lithium sulfide outlet line 7 and shipped as a product. According to the lithium sulfide manufacturing facility according to the present embodiment, by incorporating the lithium sulfide manufacturing apparatus according to the present embodiment into existing desulfurization equipment, it is possible to manufacture lithium sulfide while making effective use of resources.

[0048] Hereinafter, the lithium sulfide production facility and lithium sulfide production apparatus will be described in more detail with reference to FIG. 2 . FIG. 2 is a schematic diagram of the lithium sulfide production facility. In FIG. 2 , the apparatus provided between the desulfurization apparatus 2 and the sulfur recovery apparatus 3 is the lithium sulfide production apparatus according to this embodiment. As shown in FIG. 2 , the lithium sulfide production apparatus according to this embodiment includes a reactor 1, a hydrogen sulfide inlet line 4, and a hydrogen sulfide outlet line 5. In the reactor 1, a powdered lithium source is introduced into the reactor 1 through a lithium source supply line 11, and gaseous hydrogen sulfide is introduced into the reactor 1 through the hydrogen sulfide inlet line 4, whereby the gaseous hydrogen sulfide and the powdered lithium source are reacted with each other. The hydrogen sulfide inlet line 4 may be equipped with a valve A7, and the hydrogen sulfide outlet line 5 may be equipped with a valve A8. When hydrogen sulfide is supplied to the reactor 1, the valves A7 and A8 are opened.

[0049] The hydrogen sulfide inlet line 4 may be equipped with a heat exchanger 41. In the heat exchanger 41, the temperature of the gaseous hydrogen sulfide is adjusted before it is introduced into the reactor 1. The preferred temperature of the hydrogen sulfide to be introduced into the reactor 1 is as described above.

[0050] A powdered lithium source is supplied from the lithium source supply line 11 into the reactor 1. The lithium source supply line 11 may include a dryer 111 for drying the lithium source and a hopper 112 for introducing the dried lithium source into the reactor. By configuring it in this way, it is possible to dry a lithium source containing a large amount of water (for example, lithium hydroxide monohydrate (LiOH.H ２ Even when the dryer 110 is used, anhydrous lithium hydroxide can be obtained by the dryer 111, and powdered lithium hydroxide with a low water content can be introduced into the reactor, thereby further improving the reaction yield. The lithium source supply line 11 may be equipped with a valve B1. When the lithium source is supplied into the reactor 1, the valve B1 is opened.

[0051] The hydrogen sulfide outlet line 5 may be equipped with a dust removal filter 53. In the reactor 1, the reaction is carried out while releasing moisture, which is a solid-gas reaction, and therefore, powder fluidized in the reactor may be entrained with unreacted hydrogen sulfide and released into the hydrogen sulfide outlet line 5. In such cases, there is a possibility that the piping may be clogged, and therefore it is preferable to provide a dust removal filter 53.

[0052] The hydrogen sulfide outlet line 5 may be provided with a water condenser 51 as a cooling device. The gas discharged from the reactor 1 contains water as well as unreacted hydrogen sulfide. The water condenser 51 cools the gas discharged from the reactor 1 and condenses the water.

[0053] The hydrogen sulfide outlet line 5 may include a gas-liquid separator 52. The gas-liquid separator 52 separates the gas from which water has been condensed by the water condenser 51 into a liquid phase and a gas phase. The separated gas phase contains hydrogen sulfide and is sent to the sulfur recovery unit 3. The gas-liquid separator 52 may have a valve C1 at its bottom. The liquid phase containing water accumulated in the gas-liquid separator 52 is released by opening the valve C1.

[0054] The hydrogen sulfide outlet line 5 may be equipped with a blower 54. When the pressure of hydrogen sulfide is reduced, the moisture in the hydrogen sulfide gas is more easily evaporated, making it easier to discharge the hydrogen sulfide gas outside the reactor system; however, it is preferable to increase the pressure when supplying the hydrogen sulfide gas to the sulfur recovery unit 3. Furthermore, when the hydrogen sulfide gas passes through the gas-liquid separator 52, the moisture contained in the hydrogen sulfide gas discharged from the reactor 1 tends to condense, causing a decrease in pressure. Therefore, it is preferable to pressurize the hydrogen sulfide gas with the blower 54 and supply it to the sulfur recovery unit 3.

[0055] The hydrogen sulfide outlet line 5 may have a circulation flow path 55 that introduces the hydrogen sulfide separated by the gas-liquid separator 52 back into the water condenser 51. Providing the circulation flow path 55 makes it easier to ensure the minimum flow rate required for the acid gas blower 54 and prevents breakdowns in the acid gas blower 54, which is preferable from the perspective of protecting the machinery. The circulation flow path 55 may be provided with a variable valve A9 that adjusts the flow rate of the circulated hydrogen sulfide.

[0056] The lithium sulfide obtained in the reactor 1 is sent to a product filling facility 8 through a lithium sulfide outlet line 7. In the product filling facility 8, the obtained lithium sulfide is filled into a transfer container to obtain a lithium sulfide product. The reactor 1 may have a valve B2 at its bottom. The lithium sulfide produced in the reactor 1 is extracted by opening the valve B1.

[0057] The lithium sulfide production facility may have a bypass line 6 that supplies hydrogen sulfide directly from the desulfurization device 2 to the sulfur recovery device 3. By providing the bypass line 6, even when the reaction in the reactor 1 is a batch type, hydrogen sulfide can be safely treated by sending hydrogen sulfide directly from the desulfurization device 2 to the sulfur recovery device 3 via the bypass line 6. The lithium sulfide production facility may have valves A2, A3, A4, and A5 so that the hydrogen sulfide inlet line 4 that supplies hydrogen sulfide generated from the desulfurization device 2 to the reactor 1 can be switched between the bypass line 6 and the hydrogen sulfide inlet line 4. When hydrogen sulfide generated from the desulfurization device 2 is supplied to the hydrogen sulfide inlet line 4, the valves A2 and A5 are opened, and the valves A3 and A4 are closed. On the other hand, when hydrogen sulfide is supplied directly from the desulfurization device 2 to the sulfur recovery device 3, the valves A3 and A4 are opened, and the valves A2 and A5 are closed.

[0058] As shown in FIG. 2 , the reactor 1 has a lithium source inlet 17 through which a lithium source is introduced into the housing 12 from a lithium source supply line 11 .

[0059] The lithium sulfide obtained in the reactor 1 is extracted from the reactor 1 through the lithium sulfide outlet 18 and sent to the lithium sulfide outlet line 7.

[0060] Next, the desulfurization apparatus will be described using an example of a hydrodesulfurization apparatus for kerosene. FIG. 3 is a schematic diagram of the desulfurization apparatus. As shown in FIG. 3, the desulfurization apparatus 2 includes a hydrodesulfurization tower 21 and a hydrogen sulfide separation and recovery apparatus 22. The hydrodesulfurization tower 21 includes a catalyst packed bed 211 packed with a hydrodesulfurization catalyst. The hydrodesulfurization tower 21 is connected to a hydrogen supply line 212 and a kerosene supply line 213. The kerosene supplied from the kerosene supply line 213 and the hydrogen supplied from the hydrogen supply line 212 come into contact with the catalyst packed in the catalyst packed bed 211 in the hydrodesulfurization tower 21, and the sulfur compounds contained in the kerosene react with the hydrogen to produce hydrogen sulfide. After the hydrodesulfurization reaction, the kerosene, together with unreacted hydrogen and the produced hydrogen sulfide, is discharged from an outlet 214 to the hydrodesulfurization tower 21 via a treated kerosene line 215.

[0061] The desulfurization unit 2 may have a gas-liquid separator 23. The kerosene containing hydrogen sulfide is delivered from the hydrodesulfurization tower 21 to the gas-liquid separator 23 and separated into a gas containing hydrogen and hydrogen sulfide and liquid kerosene. The separated kerosene is refined as necessary and then used as a desulfurized kerosene product. The gas containing hydrogen and hydrogen sulfide separated by the gas-liquid separator 23 is sent to the hydrogen sulfide separation and recovery unit 22 via a gas supply line 231.

[0062] The hydrogen sulfide separation and recovery device 22 separates hydrogen and hydrogen sulfide and recovers the hydrogen and hydrogen sulfide, respectively. In the hydrogen sulfide separation and recovery device 22, the gas containing hydrogen and hydrogen sulfide is treated with an aqueous amine solution to chemically adsorb the hydrogen sulfide. The chemically adsorbed hydrogen sulfide is desorbed by heating the aqueous amine solution, and the desorbed hydrogen sulfide containing water is discharged to the reactor 1 via the hydrogen sulfide inlet line 4.

[0063] Although the detailed configuration of the sulfur recovery unit 3 is not shown, the sulfur recovery unit 3 may treat hydrogen sulfide by the Claus process to generate and recover elemental sulfur. In the Claus process, for example, hydrogen sulfide is partially combusted with air in a reactor to generate a mixed gas containing 1 mole of sulfur dioxide per 2 moles of hydrogen sulfide, and the mixed gas is brought into contact with a catalyst to generate elemental sulfur. The sulfur recovery unit 3 may be equipped with a cooler, and the cooler may be used to recover vaporous sulfur as molten sulfur.

[0064] [Method for Producing Lithium Sulfide] The present embodiment relates to a method for producing lithium sulfide, comprising: introducing hydrogen sulfide obtained from a desulfurization apparatus into a reactor; reacting gaseous hydrogen sulfide with powdered lithium hydroxide in the reactor; and releasing unreacted hydrogen sulfide to the outside of the reactor and introducing the unreacted hydrogen sulfide into a sulfur recovery apparatus.

[0065] The above-mentioned production method will be described below together with the operation of the lithium sulfide production apparatus according to this embodiment.

[0066] First, hydrogen sulfide obtained from the desulfurization device 2 is introduced into the reactor 1. At this time, the hydrogen sulfide is introduced into the casing 12 of the reactor 1 from the gas inlet part 13 via the hydrogen sulfide inlet line 4. The hydrogen sulfide may be continuously supplied to the reactor 1. The temperature of the gaseous hydrogen sulfide may be adjusted by a heat exchanger 41 provided in the hydrogen sulfide inlet line 4.

[0067] The water content of the hydrogen sulfide gas introduced into the reactor is preferably 20 vol% or less, more preferably 10 vol% or less, and even more preferably 5 vol%. Even within this range, the reaction can be carried out without impairing the yield. The water content of the hydrogen sulfide can be controlled by condensing the water using a heat exchanger.

[0068] The temperature of the gaseous hydrogen sulfide introduced into the reactor is preferably 100 to 300°C, more preferably 150 to 250°C, and even more preferably 180 to 220°C. By maintaining the temperature within this range, high reactivity can be achieved while allowing the use of common materials such as fluororesins as the materials inside the reactor. The temperature of the hydrogen sulfide can be controlled by a heat exchanger.

[0069] Furthermore, a lithium source is introduced into the casing 12 in advance from the lithium source inlet 17 of the reactor 1. In the casing 12 into which hydrogen sulfide has been introduced, gaseous hydrogen sulfide and powdery lithium hydroxide are reacted within the reactor 1.

[0070] The water content of the lithium source is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1.5% by mass or less. The water content of the lithium source can be adjusted by drying it with a dryer 111. The water content is a value measured by a vaporization method using a Karl Fischer moisture meter at 280°C.

[0071] At this time, the temperature inside the reactor 1 is controlled by a heat medium flowing through the hollow parts of the shaft 151 and the fan-shaped stirring blade 152 and a heat medium flowing inside the jacket 16 .

[0072] The preferred temperature range inside the reactor is as described above.

[0073] In the method for producing lithium sulfide according to this embodiment, unreacted hydrogen sulfide is released outside the reactor 1 and introduced into the sulfur recovery device 3. When hydrogen sulfide is continuously introduced into the reactor 1, the unreacted hydrogen sulfide is continuously released outside the reactor. By continuously introducing the unreacted hydrogen sulfide into the sulfur recovery device 3, hydrogen sulfide can be treated safely.

[0074] Since the released hydrogen sulfide contains moisture generated in the reactor 1, it is preferable to remove the moisture by condensing it using a moisture condenser 51. The condensed moisture is then separated into gas and liquid using a gas-liquid separator 52, and the gas containing hydrogen sulfide is sent to the sulfur recovery unit 3.

[0075] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those illustrated and can be modified as appropriate. Furthermore, configurations shown in different embodiments can be partially substituted or combined with each other.

[0076] The embodiments described above encompass the following embodiments. <1> An apparatus for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with a lithium source; a hydrogen sulfide inlet line for introducing hydrogen sulfide obtained from a desulfurization apparatus into the reactor; and a hydrogen sulfide outlet line for discharging unreacted hydrogen sulfide to the outside of the reactor. <2> The apparatus for producing lithium sulfide according to <1>, wherein the hydrogen sulfide outlet line introduces unreacted hydrogen sulfide to a sulfur recovery apparatus. <3> The apparatus for producing lithium sulfide according to <1> or <2>, wherein the hydrogen sulfide outlet line comprises a heat exchanger that reduces the temperature of the hydrogen sulfide. <4> The apparatus for producing lithium sulfide according to any of <1> to <3>, wherein the hydrogen sulfide outlet line comprises a moisture remover that reduces the moisture content of the hydrogen sulfide. <5> The apparatus for producing lithium sulfide according to any one of <1> to <4>, configured so that the amount of hydrogen sulfide introduced from the hydrogen sulfide inlet line is 0.05 mol% / h or more per mol of lithium source. <6> The apparatus for producing lithium sulfide according to any one of <1> to <5>, configured so that the temperature of the hydrogen sulfide released from the reactor to the hydrogen sulfide outlet line is 150°C or higher. <7> The apparatus for producing lithium sulfide according to any one of <1> to <6>, further comprising: a dryer for drying the lithium source; and a lithium source inlet line for introducing the lithium source dried by the dryer into the reactor. <8> The apparatus for producing lithium sulfide according to any one of <1> to <7>, wherein the hydrogen sulfide introduced into the reactor has a water content of 20 vol% or less. <9> The apparatus for producing lithium sulfide according to any one of <1> to <8>, wherein the temperature of the hydrogen sulfide introduced into the reactor is 100 to 300°C. <10> The apparatus for producing lithium sulfide according to any one of <1> to <9>, wherein the reactor has a mechanism for fluidizing powder. <11> The apparatus for producing lithium sulfide according to any one of <1> to <10>, wherein the lithium source is lithium hydroxide. <12> The apparatus for producing lithium sulfide according to any one of <1> to <11>, wherein the lithium source is lithium carbonate.<13> A facility for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with a lithium source; a desulfurization unit; a sulfur recovery unit; a hydrogen sulfide inlet line for introducing hydrogen sulfide obtained from the desulfurization unit into the reactor; and a hydrogen sulfide outlet line for discharging unreacted hydrogen sulfide to the reactor and introducing it into the sulfur recovery unit. <14> The facility for producing lithium sulfide according to <13>, wherein the desulfurization unit has a hydrogen sulfide treatment unit that uses a liquid composition containing water, and the hydrogen sulfide treated by the hydrogen sulfide treatment unit is introduced into the hydrogen sulfide inlet line. <15> The facility for producing lithium sulfide according to <13> or <14>, further comprising a bypass line for supplying hydrogen sulfide directly from the desulfurization unit to the sulfur recovery unit. <16> The facility for producing lithium sulfide according to any of <13> to <15>, wherein the hydrogen sulfide outlet line is equipped with a heat exchanger for lowering the temperature of the hydrogen sulfide. <17> The facility for producing lithium sulfide according to any one of <13> to <16>, wherein the hydrogen sulfide outlet line is equipped with a moisture remover that reduces the moisture content of the hydrogen sulfide. <18> The facility for producing lithium sulfide according to any one of <13> to <17>, wherein the amount of hydrogen sulfide introduced from the hydrogen sulfide inlet line is configured to be 0.05 mol% / h or more per 1 mol of lithium source. <19> The facility for producing lithium sulfide according to any one of <13> to <18>, wherein the temperature of the hydrogen sulfide released from the reactor to the hydrogen sulfide outlet line is 150°C or more. <20> A method for producing lithium sulfide, comprising: introducing hydrogen sulfide obtained from a desulfurization device into a reactor; reacting hydrogen sulfide with a lithium source in the reactor; and releasing unreacted hydrogen sulfide to the outside of the reactor and introducing it into a sulfur recovery device. <21> The method for producing lithium sulfide according to <20>, wherein the lithium source is lithium hydroxide. <22> The method for producing lithium sulfide according to <20> or <21>, wherein an amount of hydrogen sulfide introduced into the reactor is 0.05 mol% or more per 1 mol of the lithium source.<23> The method for producing lithium sulfide according to any one of <20> to <22>, wherein the temperature of the hydrogen sulfide released from the reactor is 150° C. or higher. <24> The method for producing lithium sulfide according to any one of <20> to <23>, wherein an amount of hydrogen sulfide introduced into the reactor is 0.05 mol % or higher per 1 mol of the lithium source.

[0077] 1... reactor, 2... desulfurization device, 3... sulfur recovery device, 4... hydrogen sulfide inlet line, 5... hydrogen sulfide outlet line, 6... bypass line, 7... lithium sulfide outlet line, 11... lithium source supply line, 12... housing, 13... gas inlet, 16... jacket, 17... lithium source inlet, 18... lithium sulfide outlet, 21... hydrodesulfurization tower, 22... hydrogen sulfide separation and recovery device, 23... gas-liquid separator, 41... heat exchanger, 51... moisture Condenser, 52...gas-liquid separator, 53...dust removal filter, 54...blower, 55...circulation flow path, 111...dryer, 112...hopper, 151...shaft, 152...fan-shaped stirring blade, 211...catalyst packed bed, 212...hydrogen supply line, 213...kerosene supply line, 214...extraction port, 215...treated kerosene line, 231...gas supply line, A2, A3, A4, A5, A7, A8, B1, B2, C1...valves, A9...variable valve

Claims

1. An apparatus for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with a lithium source; a hydrogen sulfide inlet line for introducing hydrogen sulfide obtained from a desulfurization apparatus into the reactor; and a hydrogen sulfide outlet line for discharging unreacted hydrogen sulfide out of the reactor.

2. The lithium sulfide production apparatus according to claim 1, wherein the hydrogen sulfide outlet line introduces unreacted hydrogen sulfide into a sulfur recovery unit.

3. The lithium sulfide manufacturing apparatus according to claim 1 or 2, wherein the hydrogen sulfide outlet line is equipped with a heat exchanger that reduces the temperature of the hydrogen sulfide.

4. The lithium sulfide manufacturing apparatus according to any one of claims 1 to 3, wherein the hydrogen sulfide outlet line is equipped with a moisture remover that reduces the moisture content of the hydrogen sulfide.

5. The apparatus for producing lithium sulfide according to any one of claims 1 to 4, further comprising: a dryer that dries the lithium source; and a lithium source inlet line through which the lithium source dried by the dryer is introduced into the reactor.

6. The lithium sulfide production apparatus according to any one of claims 1 to 5, wherein the reactor has a mechanism for fluidizing the powder.

7. The apparatus for producing lithium sulfide according to any one of claims 1 to 6, wherein the lithium source is lithium hydroxide.

8. The lithium sulfide production apparatus according to any one of claims 1 to 7, wherein the lithium source is lithium carbonate.

9. A facility for producing lithium sulfide, comprising: a reactor for reacting hydrogen sulfide with a lithium source; a desulfurization device; a sulfur recovery device; a hydrogen sulfide inlet line through which hydrogen sulfide obtained from the desulfurization device is introduced into the reactor; and a hydrogen sulfide outlet line through which unreacted hydrogen sulfide is released from the reactor and introduced into the sulfur recovery device.

10. The lithium sulfide production facility according to claim 9, wherein the desulfurization unit has a hydrogen sulfide treatment unit that uses a liquid composition containing water, and the hydrogen sulfide treated by the hydrogen sulfide treatment unit is introduced into a hydrogen sulfide inlet line.

11. The lithium sulfide production facility according to claim 9 or 10, further comprising a bypass line for supplying hydrogen sulfide directly from the desulfurization unit to the sulfur recovery unit.

12. The lithium sulfide production facility according to any one of claims 9 to 11, wherein the hydrogen sulfide outlet line is equipped with a heat exchanger that reduces the temperature of the hydrogen sulfide.

13. The facility for producing lithium sulfide according to any one of claims 9 to 12, wherein the hydrogen sulfide outlet line is equipped with a moisture remover that reduces the moisture content of the hydrogen sulfide.

14. A method for producing lithium sulfide, comprising: introducing hydrogen sulfide obtained from a desulfurization device into a reactor; reacting the hydrogen sulfide with a lithium source in the reactor; and releasing unreacted hydrogen sulfide outside the reactor and introducing it into a sulfur recovery device.

15. The method for producing lithium sulfide according to claim 14, wherein the lithium source is lithium hydroxide.

16. The method for producing lithium sulfide according to claim 14 or 15, wherein the amount of hydrogen sulfide introduced into the reactor is 0.05 mol % or more per mol of the lithium source.

17. The method for producing lithium sulfide according to any one of claims 14 to 16, wherein the temperature of the hydrogen sulfide released from the reactor is 150°C or higher.

18. The method for producing lithium sulfide according to any one of claims 14 to 17, wherein the amount of hydrogen sulfide introduced into the reactor is 0.05 mol% or more per mol of the lithium source.

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