阅读说明：本技术 焦化脱硫废渣制备不溶性硫磺的方法和工艺 (Method and process for preparing insoluble sulfur from coking desulfurization waste residues ) 是由 陈惜明 刘思颖 梁龙 刘龙涛 蔡梦宇 于 2020-12-17 设计创作，主要内容包括：本发明公开了焦化脱硫废渣制备不溶性硫磺的方法和工艺,属于焦化脱硫废渣制备硫磺的方法领域,本发明采用了混合萃取剂虽然溶解性能稍有降低,但是可以在较高的温度下保持稳定,有效的避免了二硫化碳易燃易爆的缺陷,并且溶解性能相较四氯乙烯和混合二甲苯有了明显提升,可以在较高的温度条件下溶解硫渣,然后降温,使硫磺单质析出,并且本发明采用气化法制备不溶性硫磺,制备产物达到要求,并提出了最佳的工艺制备条件,在该条件得到不溶性硫磺的收率在34％以上,产品热稳定性可以达到69.03％,不仅提高了产物的收率,并且大大提高了产品的热稳定性,使其具备量产的可能。(The invention discloses a method and a process for preparing insoluble sulfur from coking desulfurization waste residue, which belong to the field of methods for preparing sulfur from coking desulfurization waste residue, and the invention adopts a mixed extractant, although the solubility is slightly reduced, but can be kept stable at higher temperature, effectively avoids the defects of flammability and explosiveness of carbon disulfide, and the solubility is obviously improved compared with tetrachloroethylene and mixed dimethylbenzene, the sulfur slag can be dissolved at higher temperature, then cooling to separate out sulfur simple substance, and the invention adopts gasification method to prepare insoluble sulfur, the prepared product meets the requirement, and provides the best process preparation condition, the yield of the insoluble sulfur obtained under the condition is over 34 percent, the thermal stability of the product can reach 69.03 percent, the yield of the product is improved, the thermal stability of the product is greatly improved, and the possibility of mass production is realized.)

1. The method and the process for preparing insoluble sulfur by coking desulfurization waste residue are characterized by comprising the following steps:

s1, delivering the foam sulfur from the coking HPF desulfurization process desulfurizing tower to a plate-and-frame filter press through a foam delivery pump for filter pressing;

s2, conveying a filter cake generated after filter pressing of the plate-and-frame filter press in the S1 to a fluidized bed dryer for drying, and conveying a dried product to a stirring kettle for preliminary dissolution;

s3, adding purified water into the stirring kettle in the S2, starting the stirring kettle, heating at the speed of 10 ℃/min, heating to 80-100 ℃, and keeping the temperature and stirring for 25-35 min;

s4, after the stirring of the stirring kettle in the S3 is finished, maintaining the temperature at 70-90 ℃ for suction filtration, filtering a suction filtration product through a filter, and conveying a filtrate to the vacuum stirring kettle;

s5, adding powdered activated carbon into the vacuum stirring kettle in the S4, decoloring for 28-42 hours at normal temperature, filtering out the activated carbon, evaporating the filtrate under vacuum condition, and cooling the residual filtrate and residues to obtain an extraction mixture;

s6, drying the extraction mixture in S5, crushing and sieving the dried product to 160-180 meshes, conveying the dried product to an extraction kettle, and adding a mixed extraction agent to extract sulfur in the extraction kettle;

s7, conveying the mixed extracting agent extracted in the step S6 to a negative pressure stirring kettle, and removing the mixed extracting agent under the negative pressure condition to prepare high-purity sulfur;

s8, weighing 1kg of high-purity sulfur with dry mass in the S6, adding the sulfur into a vacuum reaction kettle, vacuumizing, filling nitrogen and vacuumizing for three times continuously, and completely exhausting air in the kettle to enable the vacuum degree in the reaction kettle to be more than 0.08 atm;

s9, heating the vacuum reaction kettle in the S8, setting the initial temperature to be 400 ℃, heating to the specified temperature after the temperature reaches and stabilizes, keeping the temperature for a specified time, unscrewing a valve, and spraying sulfur steam in the kettle into 7.5-8kg of organic hydrocarbon quenching liquid by the pressure of the sulfur steam in the kettle;

s10, taking out viscoelastic substances from the organic hydrocarbon quenching liquid, cleaning the crude product for 3-4 times by using 1-1.5L 30% -50% of petroleum ether by mass fraction, removing the organic hydrocarbon covered on the crude product, then placing the crude product in a constant-temperature vacuum drying oven at 55-65 ℃ for solidification and drying for 5-8h, taking out the solidified product, and transferring the solidified product into a dryer for cooling;

s12, crushing the cooled product in the S11 by a crusher, adding the crushed product into an extraction stirring kettle, and mixing the crushed product and the extraction stirring kettle according to a mass-volume ratio of 1: adding carbon disulfide as an extractant in the proportion of 6, stirring for 30min to dissolve and remove unconverted common sulfur in the crude product by the extractant, performing suction filtration on the extract liquor in the extraction stirring kettle, washing the extraction stirring kettle with pure water for three times during suction filtration, ensuring that all soluble sulfur is washed away, and drying the residual insoluble sulfur solid in a vacuum drying oven at the temperature of 55-65 ℃ for 1h at constant temperature to obtain the insoluble sulfur.

2. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: in the step S3, the mass ratio of the dry product to the purified water is 1: purified water was added at a ratio of 1.

3. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: the granularity of the activated carbon in the S5 is 0.125-0.075 mm.

4. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: the mixed extractant in the S6 is a mixed product of carbon disulfide, tetrachloroethylene and mixed xylene, wherein the mass ratio of the carbon disulfide to the tetrachloroethylene to the mixed xylene is 3: 0.5: mixing at a ratio of 0.2.

5. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: evaporating in the S5 to 1% -3% of the original filtrate.

6. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: and the mixed extracting agent in the S7 is recycled.

7. The method and process for preparing insoluble sulfur from coking desulfurization waste residue according to claim 1, characterized in that: the organic hydrocarbon quenching liquid in the S9 is aviation kerosene, wherein the stabilizer is 1% of ISX-2.

Technical Field

The invention relates to the field of a method for preparing sulfur from coking desulfurization waste residues, in particular to a method and a process for preparing insoluble sulfur from coking desulfurization waste residues.

Background

Most of domestic coke-oven plants utilize coke oven gas to synthesize methanol, and the copper-based catalyst used in the synthesis of methanol requires that the volume fraction of total sulfur is less than 0.5ppm, so that the coke oven gas desulfurization process is an essential process for obtaining clean gas in the coke-oven plants. The sulfur element in coal is firstly reacted with hydrogen and water vapor at high temperature to be converted into hydrogen sulfide, and then is removed after being reacted with a desulfurizer in a desulfurizing tower. Common desulfurization methods are classified into dry desulfurization and wet desulfurization. The dry desulfurization has good desulfurization effect, can remove hydrogen sulfide and impurities such as hydrogen cyanide and tar mist, but the dry desulfurization generally has the defects of difficult regeneration of a desulfurizer, large floor area, small coal gas treatment capacity and the like, and is usually used in occasions requiring fine desulfurization. The coke oven gas has high sulfur content and large gas treatment capacity, and wet desulphurization is generally adopted. The HPF method is one of wet desulfurizing, and the method uses ammonia in coke oven gas as absorbent and makes H in the gas react under the catalytic action of HPF₂The acidic components such as S and the like are converted into acidic ammonium salts such as ammonium thiocyanate and the like, the HPF catalyst has the advantages of high catalytic activity, good fluidity and catalytic action in the whole process of desulfurization and regeneration, the desulfurization efficiency is more than 99 percent, the decyanation efficiency is 80 percent, but the byproduct sulfur impurities of the desulfurization process of the HPF method are more, and the direct sale is difficult.

In the prior art, tetrachloroethylene and trichloroethylene are used as extracting agents to extract sulfur from sulfur slag; or carbon disulfide is used for leaching sulfur and then purifying, but the carbon disulfide has certain toxicity, is inflammable and explosive, and a treatment method is used for preparing acid by using desulfurization waste residues and waste liquid, so that the industrial production is realized by enterprises at present. But the desulfurization waste liquid contains some thiocyanate and thiosulfate with higher additional valence and is not reasonably utilized.

Disclosure of Invention

The invention provides a method and a process for preparing insoluble sulfur by coking desulfurization waste residues to solve the problems.

In order to achieve the purpose, the invention adopts the following technical scheme:

the method and the process for preparing insoluble sulfur by coking desulfurization waste residues comprise the following steps:

s1, delivering the foam sulfur from the coking HPF desulfurization process desulfurizing tower to a plate-and-frame filter press through a foam delivery pump for filter pressing;

s2, conveying a filter cake generated after filter pressing of the plate-and-frame filter press in the S1 to a fluidized bed dryer for drying, and conveying a dried product to a stirring kettle for preliminary dissolution;

s3, adding purified water into the stirring kettle in the S2, starting the stirring kettle, heating at the speed of 10 ℃/min, heating to 80-100 ℃, and keeping the temperature and stirring for 25-35 min;

s4, after the stirring of the stirring kettle in the S3 is finished, maintaining the temperature at 70-90 ℃ for suction filtration, filtering a suction filtration product through a filter, and conveying a filtrate to the vacuum stirring kettle;

s5, adding powdered activated carbon into the vacuum stirring kettle in the S4, decoloring for 28-42 hours at normal temperature, filtering out the activated carbon, evaporating the filtrate under vacuum condition, and cooling the residual filtrate and residues to obtain an extraction mixture;

s6, drying the extraction mixture in S5, crushing and sieving the dried product to 160-180 meshes, conveying the dried product to an extraction kettle, and adding a mixed extraction agent to extract sulfur in the extraction kettle;

s7, conveying the mixed extracting agent extracted in the step S6 to a negative pressure stirring kettle, and removing the mixed extracting agent under the negative pressure condition to prepare high-purity sulfur;

s8, weighing 1kg of high-purity sulfur with dry mass in the S6, adding the sulfur into a vacuum reaction kettle, vacuumizing, filling nitrogen and vacuumizing for three times continuously, and completely exhausting air in the kettle to enable the vacuum degree in the reaction kettle to be more than 0.08 atm;

s9, heating the vacuum reaction kettle in the S8, setting the initial temperature to be 400 ℃, heating to the specified temperature after the temperature reaches and stabilizes, keeping the temperature for a specified time, unscrewing a valve, and spraying sulfur steam in the kettle into 7.5-8kg of organic hydrocarbon quenching liquid by the pressure of the sulfur steam in the kettle;

s10, taking out viscoelastic substances from the organic hydrocarbon quenching liquid, cleaning the crude product for 3-4 times by using 1-1.5L 30% -50% of petroleum ether by mass fraction, removing the organic hydrocarbon covered on the crude product, then placing the crude product in a constant-temperature vacuum drying oven at 55-65 ℃ for solidification and drying for 5-8h, taking out the solidified product, and transferring the solidified product into a dryer for cooling;

s12, crushing the cooled product in the S11 by a crusher, adding the crushed product into an extraction stirring kettle, and mixing the crushed product and the extraction stirring kettle according to a mass-volume ratio of 1: adding carbon disulfide as an extractant in the proportion of 6, stirring for 30min to dissolve and remove unconverted common sulfur in the crude product by the extractant, performing suction filtration on the extract liquor in the extraction stirring kettle, washing the extraction stirring kettle with pure water for three times during suction filtration, ensuring that all soluble sulfur is washed away, and drying the residual insoluble sulfur solid in a vacuum drying oven at the temperature of 55-65 ℃ for 1h at constant temperature to obtain the insoluble sulfur.

Preferably, the ratio of the dry product to the purified water in the step S3 is 1: purified water was added at a ratio of 1.

Preferably, the particle size of the activated carbon in S5 is 0.125-0.075 mm.

Preferably, the mixed extractant in S6 is a mixed product of carbon disulfide, tetrachloroethylene and mixed xylene, and the mass ratio of carbon disulfide, tetrachloroethylene and mixed xylene is 3: 0.5: mixing at a ratio of 0.2.

Preferably, the evaporation in S5 is 1% -3% of the original filtrate.

Preferably, the mixed extracting agent in the S7 is recycled.

Preferably, the organic hydrocarbon quench liquid in S9 is aviation kerosene wherein the stabilizer is 1% ISX-2.

Compared with the prior art, the invention provides a method and a process for preparing insoluble sulfur from coking desulfurization waste residues, and the method and the process have the following beneficial effects:

1. the invention has the beneficial effects that: in the prior art, tetrachloroethylene and trichloroethylene are used as extracting agents to extract sulfur from sulfur slag; or carbon disulfide is used for leaching sulfur and then purifying, but the carbon disulfide has certain toxicity, is inflammable and explosive, and a treatment method is used for preparing acid by using desulfurization waste residues and waste liquid, so that the industrial production is realized by enterprises at present. The desulfurization waste liquid contains a certain amount of thiocyanate and thiosulfate with higher additional value, which are not reasonably utilized, the mixed extractant adopted in the invention has slightly reduced solubility, but can be kept stable at higher temperature, thus effectively avoiding the defects of flammability and explosiveness of carbon disulfide, obviously improving the solubility compared with tetrachloroethylene and mixed xylene, dissolving sulfur slag at higher temperature, and then cooling to separate out sulfur simple substance.

2. The invention has the beneficial effects that: the insoluble sulfur is prepared by a gasification method, the prepared product meets the requirements, the optimal process preparation conditions are provided, the yield of the insoluble sulfur obtained under the conditions is over 34 percent, the thermal stability of the product can reach 69.03 percent, the yield of the product is improved, the thermal stability of the product is greatly improved, and the possibility of mass production is realized.

Drawings

FIG. 1 is a diagram showing the extraction performance of different solvents on sulfur residue at normal pressure according to a specific embodiment of the method and process for preparing insoluble sulfur by coking desulfurization residue provided by the invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Example 1:

the method and the process for preparing insoluble sulfur by coking desulfurization waste residues comprise the following steps:

s1, delivering the foam sulfur from the coking HPF desulfurization process desulfurizing tower to a plate-and-frame filter press through a foam delivery pump for filter pressing;

s2, conveying a filter cake generated after filter pressing of the plate-and-frame filter press in the S1 to a fluidized bed dryer for drying, and conveying a dried product to a stirring kettle for preliminary dissolution;

s3, adding purified water into the stirring kettle in the S2, starting the stirring kettle, heating at the speed of 10 ℃/min, heating to 100 ℃, and keeping the temperature and stirring for 35 min;

s4, when the stirring of the stirring kettle in the S3 is finished, keeping the temperature at 90 ℃ for suction filtration, filtering a suction filtration product through a filter, and conveying a filtrate to the vacuum stirring kettle;

s5, adding powdered activated carbon into the vacuum stirring kettle in the S4, decoloring for 38 hours at normal temperature, filtering out the activated carbon, evaporating the filtrate under the vacuum condition, and cooling the residual filtrate and residues to obtain an extraction mixture;

s6, drying the extraction mixture in the S5, crushing and screening the dried product to 180 meshes, conveying the product to an extraction kettle, and adding a mixed extractant to extract sulfur in the product;

and S7, conveying the mixed extracting agent extracted in the step S6 to a negative pressure stirring kettle, and removing the mixed extracting agent under the negative pressure condition to obtain the high-purity sulfur.

Further, preferably, the ratio in S3 is in terms of dry product: the mass ratio of the purified water is 1: purified water was added at a ratio of 1.

Further, preferably, the particle size of the activated carbon in S5 is 0.125 to 0.075 mm.

Further, preferably, the mixed extractant in S6 is a mixed product of carbon disulfide, tetrachloroethylene and mixed xylene, and the mass ratio of carbon disulfide, tetrachloroethylene and mixed xylene is: 3: 0.5: mixing at a ratio of 0.2.

Further, preferably, 1% -3% of the original filtrate in S5.

Further, preferably, the mixed extractant in S7 is recycled.

Example 2: this example is based on example 1, but differs therefrom, in that the extracting agent in S6 is extracted by using carbon disulfide, tetrachloroethylene and mixed xylene, and the dissolving capacity of the extracting agent to sulfur residue is shown in the following fig. 1;

the invention tests the dissolving capacity of carbon disulfide, tetrachloroethylene, mixed xylene and mixed extractant to sulfur residue under normal pressure, as shown in figure 1. Test results show that tetrachloroethylene and mixed xylene have almost no dissolving capacity on sulfur slag, carbon disulfide has good dissolving capacity on sulfur slag, and the carbon disulfide has a rapid growth trend along with the increase of temperature, but has a low boiling point and starts to vaporize after the temperature exceeds 47 ℃. Although the boiling point of the solvent can be increased under the pressurization condition, the carbon disulfide is flammable and explosive, and the safety is poor under the high-pressure condition. Free carbon particles from the coke oven are present in the sulfur residue and cannot be dissolved by the carbon disulfide, so that the sulfur residue can be removed by a filtration method. Therefore, the mixed extractant is adopted, the solubility can be seen from a solubility diagram, although the solubility is slightly reduced, the mixed extractant can be kept stable at a higher temperature, the defect that carbon disulfide is inflammable and explosive is effectively avoided, the solubility is obviously improved compared with tetrachloroethylene and mixed dimethylbenzene, sulfur slag can be dissolved at a higher temperature, and then the temperature is reduced, so that elemental sulfur is separated out.

Example 3: the embodiment is based on the embodiment 1, but is different from the embodiment in that 1kg of high-purity sulfur with dry mass is weighed and added into a vacuum reaction kettle, then the vacuum treatment is carried out, then nitrogen gas is filled and the vacuum is carried out continuously for three times, and the air in the kettle is completely expelled, so that the vacuum degree in the reaction kettle reaches more than 0.08 atm;

heating a vacuum reaction kettle, setting the initial temperature to be 400 ℃, heating to the specified temperature after the temperature reaches and stabilizes, keeping the temperature for a specified time, unscrewing a valve, and spraying sulfur steam in the kettle into 7.5-8kg of organic hydrocarbon quenching liquid by the pressure of the sulfur steam in the kettle;

taking out viscoelastic substances from the organic hydrocarbon quenching liquid, cleaning the crude product for 3-4 times by using 1-1.5L of 30-50% petroleum ether by mass fraction to remove the organic hydrocarbon covered on the crude product, then placing the crude product in a constant-temperature vacuum drying oven at 55-65 ℃ for solidification and drying for 5-8h, taking out the solidified product, and transferring the solidified product into a dryer for cooling;

and crushing the cooled product by a crusher, adding the crushed product into an extraction stirring kettle, and mixing the crushed product with the extraction stirring kettle according to the mass-to-volume ratio of 1: 6, adding an extractant carbon disulfide into the crude product, stirring the mixture for 30min to dissolve and remove unconverted common sulfur in the crude product by the extractant, performing suction filtration on an extract liquor in an extraction stirring kettle, washing the extraction stirring kettle for three times by using pure water during suction filtration, ensuring that all soluble sulfur is washed away, and drying the remaining insoluble sulfur solid in a vacuum drying oven at the temperature of 55-65 ℃ for 1h at constant temperature to prepare insoluble sulfur;

further, preferably, the organic hydrocarbon quenching liquid in S9 is aviation kerosene, wherein the stabilizer is 1% of ISX-2;

example 3 was repeated a plurality of times, and the prepared insoluble sulfur product was subjected to insoluble sulfur mass fraction measurement, acidity mass fraction measurement, heating loss fraction measurement, and the like, and the measurement data are shown in table 1 below:

TABLE 1 insoluble Sulfur product detection Table

The invention adopts a gasification method to prepare insoluble sulfur, and the prepared product meets the requirements by referring to the table 1 above, wherein the optimal process preparation condition is that aviation kerosene is used as quenching liquid, 1% of stabilizer ISX-2 is added, and the quenching liquid is quenched at the reaction temperature of 450 ℃, the reaction time of 20min and the quenching liquid temperature of 20 ℃, the yield of the insoluble sulfur obtained by the condition is more than 34%, and the thermal stability of the product can reach 69.03%.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.