阅读说明：本技术 一种脱硫废液中硫的高效分离提纯的装置和方法 (Device and method for efficiently separating and purifying sulfur in desulfurization waste liquid ) 是由 王庆伟 张光春 林璋 杨琛 柴立元 王一 陶柏润 李青竹 颜旭 田晨 刘恢 闵 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种脱硫废液中硫的高效分离提纯的装置和方法,该装置包括固液分离器、气浮熔硫釜、精细分离器和解析分离器；气浮熔硫釜的硫滤饼加料口和硫液出口分别与固液分离器的固相出口和精细分离器的进料口相连；精细分离器的溶硫液出口与解析分离器的进料口相连。本发明可快速将脱硫废液中的粗硫磺、焦油和杂质在气浮熔硫釜中分开,节省能耗；利用系统循环的再生回收液进行提纯分离,在解析分离硫磺的同时回收有效成分,得到再生回收液返回精细分离器,避免对环境造成危害,减少运行成本；所提供的硫的高效分离提纯的装置,尤其是气浮熔硫釜,设计巧妙科学,所提纯生产的工业硫磺纯度在99.5％以上,易于大规模推广使用。(The invention discloses a device and a method for efficiently separating and purifying sulfur in desulfurization waste liquid, wherein the device comprises a solid-liquid separator, an air-flotation sulfur melting kettle, a fine separator and an analytical separator; a sulfur filter cake feeding port and a sulfur liquid outlet of the air-flotation sulfur melting kettle are respectively connected with a solid phase outlet of the solid-liquid separator and a feeding port of the fine separator; the sulfur solution outlet of the fine separator is connected with the feed inlet of the desorption separator. The invention can quickly separate crude sulfur, tar and impurities in the desulfurization waste liquid in the air-flotation sulfur melting kettle, thereby saving energy consumption; the regenerated recovery liquid circulated by the system is used for purification and separation, the effective components are recovered while the sulfur is analyzed and separated, the obtained regenerated recovery liquid returns to the fine separator, the harm to the environment is avoided, and the operation cost is reduced; the device for efficiently separating and purifying the sulfur, in particular to the air-float sulfur melting kettle, has ingenious and scientific design, the purity of the industrial sulfur produced by purification is more than 99.5 percent, and is easy to popularize and use on a large scale.)

1. A device for efficiently separating and purifying sulfur in desulfurization waste liquid, which is characterized in that,

comprises a solid-liquid separator, an air-flotation sulfur melting kettle, a fine separator and an analytical separator;

a sulfur filter cake feeding port and a sulfur liquid outlet of the air floatation sulfur melting kettle are respectively connected with a solid phase outlet of the solid-liquid separator and a feeding port of the fine separator;

and a sulfur solution outlet of the fine separator is connected with a feed inlet of the desorption separator.

2. The apparatus for efficiently separating and purifying sulfur in a desulfurization waste liquid according to claim 1,

the air-floatation sulfur melting kettle comprises a kettle body and a jacket layer arranged outside the kettle body;

a baffle plate is fixedly arranged on the inner wall of the kettle body, the sulfur filter cake feeding port is arranged between the baffle plate and the inner wall of the kettle body close to one side of the baffle plate, the inner wall of the kettle body far away from one side of the baffle plate is sequentially provided with a water-scum outlet and a sulfur liquid outlet from top to bottom, the top of the kettle body far away from one side of the baffle plate is provided with a tail gas suction port, and the bottom of the kettle body is provided with a heavy slag outlet;

and the bottom and the top of the jacket layer are respectively provided with a heat source inlet and a heat source outlet.

3. The apparatus for efficiently separating and purifying sulfur in a desulfurization waste liquid according to claim 2,

the air-floatation sulfur melting kettle further comprises a thermometer port arranged at the top of the kettle body and/or a plurality of air pipe inlets uniformly arranged at the bottom of the side surface of the kettle body.

4. The apparatus for efficiently separating and purifying sulfur in desulfurized waste liquid according to claim 2 or 3, wherein,

the system also comprises a tail gas absorption tower and/or a hot-pressing separator;

the tail gas absorption tower is connected with a tail gas absorption port of the air floatation sulfur melting kettle;

the hot-pressing separator is connected with a water-scum outlet and a heavy-scum outlet of the air-floatation sulfur melting kettle.

5. The apparatus for efficiently separating and purifying sulfur in a desulfurized waste liquid according to any one of claims 1 to 4, wherein,

and also comprises H₂S, an absorption tower;

said H₂And a waste gas inlet and a regenerated liquid outlet of the S absorption tower are respectively connected with a hydrogen sulfide outlet of the desorption separator and a recycling agent inlet of the fine separator.

6. A method for efficiently separating and purifying sulfur in desulfurization waste liquid, which is characterized in that,

the method comprises the following steps:

s1, treating the desulfurization waste liquid by using a solid-liquid separator to obtain a sulfur-containing filter cake with the water content of 20-50%;

s2, introducing the sulfur-containing filter cake obtained in the step S1 into an air-flotation sulfur melting kettle, firstly heating to control the temperature of the air-flotation sulfur melting kettle to be 75-90 ℃, separating water in the sulfur-containing filter cake, then discharging the sulfur-containing filter cake from a water-scum outlet of the air-flotation sulfur melting kettle, then heating to control the temperature of the air-flotation sulfur melting kettle to be 125-cake 165 ℃, separating scum, crude sulfur liquid and heavy slag in the sulfur-containing filter cake, and then respectively discharging the sulfur-containing filter cake from a water-scum outlet, a sulfur liquid outlet and a heavy slag outlet of the air-flotation sulfur melting kettle;

s3, introducing the crude sulfur liquid in the step S2 into a fine separator, and adding S^2-Ions and/or HS^-Recovering agent of ion, solid-liquid separation after reaction to obtain sulfur-dissolving liquid and tar;

s4, introducing the sulfur-dissolved solution obtained in the step S3 into an analytical separator, adding inorganic acid to react for 30-120min, controlling the pH value in the analytical separator in the reaction process to be 5-9, and carrying out gas-solid-liquid separation to obtain hydrogen sulfide, high-purity sulfur and analyzed solution.

7. The method for efficiently separating and purifying sulfur in desulfurized waste liquid according to claim 6, wherein,

also comprises the following steps of (1) preparing,

s5, introducing the hydrogen sulfide in the step S4 into H₂An inorganic alkali solution is added to the S absorption column, and after the reaction, the regenerated liquid obtained is introduced into the fine separator in step S3 and recovered for reuse.

8. The method for efficiently separating and purifying sulfur in desulfurized waste liquid according to claim 6 or 7, wherein,

in step S1, the sulfur content of the desulfurization waste liquid is 40-90 wt%;

and/or, in step S4, the inorganic acid is H₂SO₄HCl and H₂C₂O₄One or more of;

and/or, in the step S5, the inorganic base is NaOH, KOH or Na₂CO₃And NaHCO₃One or more of (a).

9. The method for efficiently separating and purifying sulfur in a desulfurized waste liquid according to any one of claims 6 to 8, wherein,

in step S2, the method further comprises,

blowing nitrogen from an air pipe inlet of the air floatation sulfur melting kettle while heating and controlling the temperature of the air floatation sulfur melting kettle to be 125-165 ℃ to accelerate the separation of scum, crude sulfur liquid and heavy slag;

and/or introducing waste gas generated in the air floatation sulfur melting kettle into a tail gas absorption tower for absorption treatment;

and/or guiding scum and heavy slag generated in the air floatation sulfur melting kettle into a hot-pressing separator, and separating to obtain impurities and recyclable tar.

10. The method for efficiently separating and purifying sulfur in a desulfurized waste liquid according to any one of claims 6 to 9, wherein,

in step S2, the temperature of the air-float sulfur melting kettle is controlled at 125-165 ℃ to separate the scum, the crude sulfur liquid and the heavy slag for 1-6 h.

Technical Field

The invention relates to the technical field of recycling of coking product desulfurization waste liquid, in particular to a device and a method for efficiently separating and purifying sulfur in desulfurization waste liquid.

Background

The coke oven gas byproduct crude sulfur of the coke-oven plant is obtained in a desulfurization working section for purifying coke oven gas, HPF wet liquid phase catalysis method which takes ammonia as alkali source is mainly adopted for desulfurization, most of sulfur foam obtained at the top of a regeneration tower recovers wet sulfur by a filter pressing method, or a sulfur melting kettle recovers solid sulfur.

In the desulfurization working section, impurities such as tar, naphthalene and the like in the coal gas not only have great influence on the desulfurization efficiency, but also seriously influence the purity of sulfur, so that the ammonia method HPF desulfurization process is the same as other desulfurization processes, and the content of the tar and the content of the naphthalene in the coal gas entering a desulfurization tower are required to be respectively less than 50mg/m³And 0.5g/m³. In the actual production, the impurities of tar, naphthalene and the like in the purified gas still cause the sulfur content of the sulfur product to be low, generally 60-75%, and the color of the sulfur product is earthy yellow or black yellow, thereby influencing the sulfur contentThe usage of the sulfur can only be sold at a very low price, even the sulfur cannot be used due to poor color or low purity sometimes, and can only be stacked in the form of solid waste, and at the present stage, if the crude sulfur cannot be timely recovered by adopting an effective technical means, a large amount of sulfur resources are wasted, the environment is seriously polluted, and potential safety hazards are brought.

The Chinese patent application with publication number CN111232934A discloses a device for utilizing desulfurization waste liquid and an operation method thereof, which adopts the procedures of sulfur incineration and two-conversion and two-absorption to prepare crude sulfur into sulfuric acid so as to achieve the purpose of recycling the crude sulfur; although the method can prepare the crude sulfur and the desulfurized liquid into the sulfuric acid by the acid preparation equipment, the waste is changed into valuable, but the method has the problems of large investment, high energy consumption, low benefit and the like.

The Chinese patent application with the publication number of CN101397127A discloses a method for purifying crude sulfur, which adopts a vacuum distillation method, controls the system pressure and the distillation temperature in an external heating type vacuum furnace to carry out vacuum distillation, and purifies the crude sulfur; the method adopts an external heating type vacuum furnace, carries out vacuum distillation under the conditions that the system pressure is 5-400Pa, the distillation temperature is 50-100 ℃ and the distillation time is 15-120min, and finally obtains purer sulfur, but has the problems of high requirements on equipment materials and performance, high energy consumption in the production process and the like.

The Chinese patent application with the publication number of CN101397127A discloses a decoloring and purifying process of coke oven gas desulfurization byproduct crude sulfur, which adopts a nonpolar organic solvent with good sulfur solubility to extract sulfur in the crude sulfur; the method adopts CS₂、C₂HCl₃And CCl₄The extraction method of organic solvent can also obtain relatively pure sulfur, but the used organic solvent has relatively high toxicity and relatively high volatility, belongs to inflammable and explosive substances, and has the problems of relatively complicated process, relatively high requirement on production safety, relatively high environmental pollution and the like.

Disclosure of Invention

In view of the above, the invention provides a device and a method for efficiently separating and purifying sulfur in a desulfurization waste liquid.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a device for efficiently separating and purifying sulfur in desulfurization waste liquid comprises a solid-liquid separator, an air floatation sulfur melting kettle, a fine separator and an analytical separator.

Specifically, a sulfur filter cake feeding port and a sulfur liquid outlet of the air-flotation sulfur melting kettle are respectively connected with a solid phase outlet of the solid-liquid separator and a feeding port of the fine separator.

Specifically, a sulfur solution outlet of the fine separator is connected with a feed inlet of the desorption separator.

In the technical scheme, the air-flotation sulfur melting kettle comprises a kettle body and a jacket layer arranged outside the kettle body.

The sulfur filter cake feeding port is arranged between the baffle plate and the inner wall of the kettle body close to one side of the baffle plate, the inner wall of the kettle body far away from one side of the baffle plate is sequentially provided with a water-scum outlet and a sulfur liquid outlet from top to bottom, the top of the kettle body far away from one side of the baffle plate is provided with a tail gas suction port, and the bottom of the kettle body is provided with a heavy slag outlet.

Specifically, the bottom and the top of the jacket layer are respectively provided with a heat source inlet and a heat source outlet.

Further, in the above technical solution, the air-flotation sulfur melting kettle further comprises a thermometer port disposed at the top of the kettle body and/or a plurality of gas pipe inlets uniformly disposed at the bottom of the side surface of the kettle body.

Still further, in the above technical solution, the device for efficiently separating and purifying sulfur in the desulfurization waste liquid further includes a tail gas absorption tower and/or a hot-pressing separator.

Specifically, the tail gas absorption tower is connected with a tail gas absorption port of the air floatation sulfur melting kettle;

specifically, the hot-pressing separator is connected with a water-scum outlet and a heavy-scum outlet of the air-flotation sulfur melting kettle.

Still further, in the above technical scheme, the device for efficiently separating and purifying sulfur in the desulfurization waste liquid further comprises H₂S absorption tower(ii) a Said H₂And a waste gas inlet and a regenerated liquid outlet of the S absorption tower are respectively connected with a hydrogen sulfide outlet of the desorption separator and a recycling agent inlet of the fine separator.

The invention also provides a method for efficiently separating and purifying sulfur in the desulfurization waste liquid, which comprises the following steps:

s1, treating the desulfurization waste liquid by using a solid-liquid separator to obtain a sulfur-containing filter cake with the water content of 20-50%;

s2, introducing the sulfur-containing filter cake obtained in the step S1 into an air-flotation sulfur melting kettle, firstly heating to control the temperature of the air-flotation sulfur melting kettle to be 75-90 ℃, separating water in the sulfur-containing filter cake, then discharging the sulfur-containing filter cake from a water-scum outlet of the air-flotation sulfur melting kettle, then heating to control the temperature of the air-flotation sulfur melting kettle to be 125-cake 165 ℃, separating scum, crude sulfur liquid and heavy slag in the sulfur-containing filter cake, and then respectively discharging the sulfur-containing filter cake from a water-scum outlet, a sulfur liquid outlet and a heavy slag outlet of the air-flotation sulfur melting kettle;

s3, introducing the crude sulfur liquid in the step S2 into a fine separator, and adding S²-ion and/or HS-ion recovery agent, solid-liquid separation after reaction to obtain sulfur-dissolved solution and tar;

s4, introducing the sulfur-dissolved solution obtained in the step S3 into an analytical separator, adding inorganic acid to react for 30-120min, controlling the pH value in the analytical separator in the reaction process to be 5-9, and carrying out gas-solid-liquid separation to obtain hydrogen sulfide, high-purity sulfur and analyzed solution.

In the above technical scheme, the method for efficiently separating and purifying sulfur in the desulfurization waste liquid further comprises,

s5, introducing the hydrogen sulfide in the step S4 into H₂An inorganic alkali solution is added to the S absorption column, and after the reaction, the regenerated liquid obtained is introduced into the fine separator in step S3 and recovered for reuse.

In the above technical solution, in step S1, the sulfur content of the desulfurized waste liquid is 40 to 90 wt%.

In the above technical solution, in step S4, the inorganic acid is H₂SO₄HCl and H₂C₂O₄One or more of (a).

In the above technical solution, in step S5, the inorganic baseIs NaOH, KOH or Na₂CO₃And NaHCO₃One or more of (a).

Further, in the above technical solution, in the step S2, the method further includes blowing nitrogen gas from an air pipe inlet of the air-flotation sulfur melting kettle while heating and controlling the temperature of the air-flotation sulfur melting kettle to 125-.

Further, in the above technical solution, in step S2, the method further includes introducing the exhaust gas generated in the air-flotation sulfur melting kettle into an off-gas absorption tower for absorption treatment.

Further, in the above technical solution, in step S2, the method further includes introducing scum and heavy slag generated in the air floatation sulfur melting kettle into a hot-pressing separator, and separating to obtain impurities and recyclable tar.

Further, in the above technical solution, in step S2, the temperature of the air-float sulfur melting kettle is controlled to 125-.

In the method for efficiently separating and purifying sulfur in the desulfurization waste liquid, the mainly involved equation is as follows:

S^2-+nS＝S_(1+n) ^2-(alkaline conditions)

S_(1+n) ^2-＝nS↓+S^2-(acid condition)

Na₂S+(x+y)S＝Na₂S_(1+x+y)

Na₂S_(1+x+y)+H₂SO₄＝(x+y)S↓+H₂S↑+Na₂SO₄

NaHS+xS＝NaHS_(1+x)

NaHS_(1+x)+H₂SO₄＝xS↓+H₂S↑+Na₂SO₄

Na₂S_(1+x+y)+H₂C₂O₂＝xS↓+H₂S↑+Na₂C₂O₂

H₂S+2NaOH＝Na₂S+H₂O

Na₂S+H₂S＝2NaHS。

Compared with the prior art, the invention has the following advantages:

(1) the method for efficiently separating and purifying the sulfur skillfully utilizes the difference of the physical properties of all components in the desulfurization waste liquid, quickly separates tar, impurities, crude sulfur and other components in the desulfurization waste liquid in the self-designed air-flotation sulfur melting kettle with a specific structure, has a good separation effect, and saves energy consumption;

(2) the method for efficiently separating and purifying the sulfur skillfully utilizes the recycled regenerated liquid, obtains high-purity sulfur by analytic separation and simultaneously utilizes H₂S, the absorption tower treats the obtained hydrogen sulfide gas, the obtained regenerated liquid is recycled and returned to the front fine separator, and a complete internal circulation system is formed, so that the harm to the environment can be avoided, and the operation cost can be reduced;

(3) the method for efficiently separating and purifying sulfur provided by the invention purifies and recovers the crude sulfur in the desulfurization waste liquid to obtain products such as tar, sulfur and the like, and separates to obtain miscellaneous salts, thereby thoroughly solving the problem that the foam desulfurization waste liquid is difficult to be effectively recycled, realizing the purification and recovery of the sulfur with low cost and creating economic benefits;

(4) the device for efficiently separating and purifying the sulfur, which is provided by the invention, particularly the self-designed air-flotation sulfur melting kettle with a specific structure, is ingenious and scientific in design, industrial sulfur purified and produced by the method for efficiently separating and purifying the sulfur can meet the national standard requirements, the purity of a sulfur product is over 99.5 percent, and the device is easy to popularize and use on a large scale.

Drawings

FIG. 1 is a process flow chart of a method for efficiently separating and purifying sulfur from a desulfurized waste liquid provided in the embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an air-flotation sulfur melting kettle of the device for efficiently separating and purifying sulfur in desulfurized waste liquid provided in the embodiment of the invention;

in the figure:

the device comprises a kettle body 1, a sulfur filter cake feeding port 2, a tail gas absorption port 3, a water-scum outlet 4, a sulfur liquid outlet 5, a heavy slag outlet 6, a heat source inlet 7, a heat source outlet 8, a jacket layer 9, a thermometer port 10, a baffle plate 11 and a gas pipe inlet 12.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments.

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the examples, the means used are conventional in the art unless otherwise specified.

The terms "comprises," "comprising," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The embodiment of the invention provides a device for efficiently separating and purifying sulfur in desulfurization waste liquid, which specifically comprises a solid-liquid separator, an air-flotation sulfur melting kettle, a fine separator and an analytical separator.

Wherein:

the solid-liquid separator is a solid-liquid separating device commonly used in the field, such as a centrifugal separator, a filter, a suction filter and the like.

The air-flotation sulfur melting kettle comprises a kettle body 1 and a jacket layer 9 arranged outside the kettle body 1, as shown in figure 2. Specifically, a baffle plate 11 is fixedly arranged on the inner wall of the kettle body 1, a sulfur filter cake feeding port 2 is arranged at the top of the kettle body between the baffle plate 11 and the inner wall of the kettle body close to one side of the baffle plate 11, a water-scum outlet 4 and a sulfur liquid outlet 5 are sequentially arranged on the inner wall of the kettle body far away from one side of the baffle plate 11 from top to bottom, a tail gas suction port 3 is arranged at the top of the kettle body far away from one side of the baffle plate 11, and a heavy slag outlet 6 is arranged at the bottom of the kettle body 1; the bottom and the top of the jacket layer 9 are respectively provided with a heat source inlet 7 and a heat source outlet 8.

The fine separator and the analytical separator are those commonly used in the art and will not be described herein.

In detail, a sulfur filter cake feeding port and a sulfur liquid outlet of the air-flotation sulfur melting kettle are respectively connected with a solid phase outlet of a solid-liquid separator and a feeding port of a fine separator; the sulfur solution outlet of the fine separator is connected with the feed inlet of the desorption separator.

In an embodiment of the present invention, the air-float sulfur melting kettle in the apparatus for efficiently separating and purifying sulfur from desulfurized waste liquid further includes a thermometer port 10 and/or a plurality of gas pipe inlets 12.

Specifically, the temperature measuring port 10 is arranged at the top of the kettle body 1 of the air-flotation sulfur melting kettle, and the plurality of gas pipe inlets 12 are uniformly arranged at the bottom of the side surface of the kettle body 1.

In a preferred embodiment of the present invention, the apparatus for efficiently separating and purifying sulfur from the desulfurized waste liquid further comprises a tail gas absorption tower and/or a hot-pressing separator.

Specifically, the tail gas absorption tower is connected with a tail gas absorption port 3 of the air floatation sulfur melting kettle; the hot-pressing separator is connected with a water-scum outlet 4 and a heavy-scum outlet 6 of the air-flotation sulfur melting kettle.

In another preferred embodiment of the present invention, the apparatus for efficiently separating and purifying sulfur from the desulfurized waste liquid further comprises H₂And (5) an S absorption tower.

Specifically, the above-mentioned H₂And a waste gas inlet and a regenerated liquid outlet of the S absorption tower are respectively connected with a hydrogen sulfide outlet of the desorption separator and a recycling agent inlet of the fine separator.

The embodiment of the invention also provides a method for efficiently separating and purifying sulfur in desulfurization waste liquid by using the device, which specifically comprises the following steps as shown in figure 1:

s1, treating the desulfurization waste liquid by using a solid-liquid separator to obtain a sulfur-containing filter cake with the water content of 20-50%, and returning the obtained separated filtrate to a desulfurization working section through a centrifugal pump;

s2, introducing the sulfur-containing filter cake obtained in the step S1 into an air-flotation sulfur melting kettle, controlling the temperature of the air-flotation sulfur melting kettle to be 75-90 ℃ through steam or electric heating, separating water in the sulfur-containing filter cake, then discharging the water-scum from a water-scum outlet of the air-flotation sulfur melting kettle, controlling the temperature of the air-flotation sulfur melting kettle to be 125-165 ℃ through steam or electric heating, and separating the scum, crude sulfur liquid and heavy slag in the sulfur-containing filter cake, then respectively discharging the scum, the crude sulfur liquid and the heavy slag from the water-scum outlet, the sulfur liquid outlet and the heavy slag outlet of the air-flotation sulfur melting kettle;

s3, introducing the crude sulfur liquid obtained in the step S2 into a fine separator, and adding S^2-Ion (Na)₂S、K₂S) and/or HS^-The recycling agent of ions (NaHS and KHS) separates sulfur and tar by utilizing the principle that sulfur ions react with sulfur and sulfur under alkaline conditions to generate polysulfide, and the sulfur-dissolved solution and the tar are obtained by solid-liquid separation after the reaction;

and S4, introducing the sulfur-dissolved solution obtained in the step S3 into an analytical separator, adding inorganic acid to react for 30-120min, controlling the pH in the analytical separator in the reaction process to be 5-9, and performing gas-solid-liquid separation to obtain hydrogen sulfide, high-purity sulfur and analyzed liquid.

In the method for efficiently separating and purifying sulfur in the desulfurization waste liquid, the mainly involved equation is as follows:

S^2-+nS＝S_(1+n) ^2-(alkaline conditions)

S_(1+n) ^2-＝nS↓+S^2-(acid condition)

Na₂S+(x+y)S＝Na₂S_(1+x+y)

Na₂S_(1+x+y)+H₂SO₄＝(x+y)S↓+H₂S↑+Na₂SO₄

NaHS+xS＝NaHS_(1+x)

NaHS_(1+x)+H₂SO₄＝xS↓+H₂S↑+Na₂SO₄

Na₂S_(1+x+y)+H₂C₂O₂＝xS↓+H₂S↑+Na₂C₂O₂

H₂S+2NaOH＝Na₂S+H₂O

Na₂S+H₂S＝2NaHS。

In an embodiment of the present invention, the method for efficiently separating and purifying sulfur from a desulfurized waste liquid further includes:

s5, introducing the hydrogen sulfide obtained in the step S4 into H₂An inorganic alkali solution is added to the S absorption column, and after the reaction, the regenerated liquid obtained is introduced into the fine separator in step S3 and recovered for reuse.

Specifically, in the method for efficiently separating and purifying sulfur in the desulfurization waste liquid, in step S1, the sulfur content of the desulfurization waste liquid is 40-90 wt%.

Specifically, in the above method for efficiently separating and purifying sulfur in the desulfurization waste liquid, in step S4, the inorganic acid is H₂SO₄HCl and H₂C₂O₄One or more of (a).

Specifically, in the above method for efficiently separating and purifying sulfur from the desulfurization waste liquid, in step S5, the inorganic base is NaOH, KOH, Na₂CO₃And NaHCO₃One or more of (a).

In a preferred embodiment of the present invention, in the above method for efficiently separating and purifying sulfur from sulfur-containing waste liquid, step S2 further includes blowing nitrogen gas from the gas inlet of the air-flotation sulfur melting kettle while controlling the temperature of the air-flotation sulfur melting kettle to be 125-165 ℃, so as to accelerate the separation of dross, crude sulfur liquid and heavy slag.

In another preferred embodiment of the present invention, in the above method for efficiently separating and purifying sulfur from desulfurized waste liquid, step S2 further includes introducing the waste gas generated in the air-float sulfur melting kettle into a tail gas absorption tower for absorption treatment.

In another preferred embodiment of the present invention, in the above method for efficiently separating and purifying sulfur from desulfurized waste liquid, step S2 further includes introducing scum and heavy slag generated in the air floatation sulfur melting kettle into a hot-pressing separator, and separating to obtain impurities and recyclable tar.

In an embodiment of the invention, in the method for efficiently separating and purifying sulfur in the desulfurization waste liquid, in step S2, the temperature of the air-float sulfur melting kettle is controlled to 125-.

Example 1

The device for efficiently separating and purifying the sulfur is used, and the method for efficiently separating and purifying the sulfur is adopted to treat the foamy desulfurization waste liquid obtained from the coke oven gas purification and desulfurization section of the coke-oven plant, and the specific process is as follows:

carrying out centrifugal separation on the foamy desulfurization waste liquid with the water content of more than 75 wt% and the sulfur content of 74.3 wt% in the solid waste to obtain a sulfur-containing filter cake with the water content of 21.5 wt%; then introducing the sulfur-containing filter cake into an air-flotation sulfur melting kettle, firstly heating to control the temperature of the air-flotation sulfur melting kettle to be 80 ℃, keeping the temperature for about 1h, separating water in the sulfur-containing filter cake, then discharging the water-scum from a water-scum outlet of the air-flotation sulfur melting kettle, subsequently heating to control the temperature of the air-flotation sulfur melting kettle to be 145 ℃, keeping the temperature for 3h, continuously blowing a small amount of nitrogen with the pressure of 0.35Mpa during the period, stopping blowing the nitrogen after the reaction is finished, discharging crude sulfur liquid from a sulfur liquid outlet in the middle of the air-flotation sulfur melting kettle, cooling to normal temperature, and then putting into a fine separator; adding the recycled regeneration liquid into a fine separator, controlling the dissolving temperature to be 40-60 ℃, stirring and reacting for 1-2h to obtain a dark red sulfur-dissolved liquid, filtering and separating to return the obtained slag to an air-flotation sulfur melting kettle, introducing the sulfur-dissolved liquid into an analytical separator, adding a 5 wt% dilute sulfuric acid aqueous solution, reacting for 75min, controlling the pH value in the analytical separator during the reaction to be 7-8, and performing gas-solid-liquid separation to obtain hydrogen sulfide, an analyzed liquid and golden yellow sulfur solid.

According to the analysis of GB/T2449-2006 standard, the purity of the prepared golden yellow sulfur solid reaches 99.8 wt%, the first-grade product requirement is met, and meanwhile, the recovery rate of sulfur in the separation and purification process is up to 95.3% through calculation.

In addition, hydrogen sulfide is introduced into H₂And (3) adding 10 wt% of sodium hydroxide solution into the S absorption tower for absorption, and returning the obtained regenerated liquid to the fine reactor for recycling after reaction.

The method for efficiently separating and purifying the sulfur skillfully utilizes the difference of the physical properties of all components in the desulfurization waste liquid, quickly separates tar, impurities, crude sulfur and other components in the desulfurization waste liquid in the self-designed air-flotation sulfur melting kettle with a specific structure, has a good separation effect, and saves energy consumption; the method for efficiently separating and purifying the sulfur skillfully utilizes the recycled regenerated liquid, processes the obtained analytic liquid by utilizing the regeneration separator while obtaining the high-purity sulfur through analytic separation, recycles the obtained regenerated liquid, returns the recycled liquid to the front fine separator, combines the front and the back, forms a complete internal circulation system, can avoid causing harm to the environment, and can reduce the operation cost; the method for efficiently separating and purifying sulfur provided by the embodiment of the invention purifies and recovers the crude sulfur in the desulfurization waste liquid to obtain products such as tar, sulfur and the like, and separates to obtain miscellaneous salts, thereby thoroughly solving the problem that the foam desulfurization waste liquid is difficult to be effectively recycled, realizing the purification and recovery of the sulfur with low cost and creating economic benefits; the device for efficiently separating and purifying the sulfur, which is provided by the embodiment of the invention, particularly the self-designed air-flotation sulfur melting kettle with a specific structure, is ingenious and scientific in design, industrial sulfur purified and produced by the method for efficiently separating and purifying the sulfur can meet the national standard requirements, the purity of a sulfur product is over 99.5 percent, and the device is easy to popularize and use on a large scale.

It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.