CN-121990525-A - Refining recovery method and refining recovery system for high-purity sulfur

CN121990525ACN 121990525 ACN121990525 ACN 121990525ACN-121990525-A

Abstract

The invention provides a high-purity sulfur refining and recycling method and a refining and recycling system, wherein the high-purity sulfur refining and recycling method comprises the steps of conveying sulfur foam generated by a wet desulfurization process into a continuous sulfur melting kettle for preliminary separation to obtain liquid crude sulfur; the method comprises the steps of conveying liquid crude sulfur into a negative pressure flash tank, then flash evaporating to remove light components in the liquid crude sulfur, purifying the liquid crude sulfur to form liquid refined sulfur, heating the liquid refined sulfur by a heat exchanger to supplement heat, conveying the liquid refined sulfur into a distillation and rectification combined device to carry out high-temperature distillation gasification and rectification deep purification to form high-temperature-state high-purity sulfur steam, and conveying at least part of the high-temperature-state high-purity sulfur steam to the heat exchanger to preheat the liquid refined sulfur by utilizing at least part of latent heat of the high-temperature-state high-purity sulfur steam, condensing the high-purity sulfur steam to form high-purity solid sulfur, and recycling the high-purity solid sulfur. The invention solves the problems of low precision of sulfur foam treatment, purification and recovery of sulfur, huge energy consumption of purification and recovery process and unstable operation of a process system in the prior art.

Inventors

LI JUNFU
LI ZHIYUN
LI JINYU
QIN XINXIN
GUO WENJUN
GUO MINGYU

Assignees

山西清迪环保科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260211

Claims (10)

1. A method for refining and recovering high purity sulfur for purifying sulfur from sulfur foam produced by a wet desulfurization process and refining the sulfur into high purity sulfur, comprising: S1, conveying sulfur foam generated by a wet desulfurization process into a continuous sulfur melting kettle (10) for preliminary separation to obtain liquid crude sulfur; S2, conveying the liquid crude sulfur into a negative pressure flash tank (20), and then flash evaporating to remove light components in the liquid crude sulfur so as to purify the liquid crude sulfur to form liquid refined sulfur; s3, heating and supplementing the liquid refined sulfur through a heat exchanger (40), and then conveying the liquid refined sulfur into a distillation and rectification combination device (30) to carry out high-temperature distillation gasification and rectification deep purification to form high-temperature high-purity sulfur steam; And S4, at least a part of the high-purity sulfur steam in a high-temperature state is passed through the heat exchanger (40) so as to utilize at least a part of latent heat of the high-purity sulfur steam to preheat the liquid refined sulfur, and then the high-purity sulfur steam is condensed to form high-purity solid sulfur and is recovered.
2. The method according to claim 1, wherein in step S2, the liquid crude sulfur is conveyed into a negative pressure flash tank (20) for spray flash evaporation, gaseous light components obtained by spray flash evaporation are pumped out of the negative pressure flash tank (20) under negative pressure and conveyed to a washing tower (70) for treatment, and the liquid components obtained by spray flash evaporation form the liquid refined sulfur.
3. The method according to claim 2, wherein in the step S2, the liquid crude sulfur is transferred into a buffer tank (60) with the temperature maintained between 150 ℃ and 160 ℃, then the liquid crude sulfur in the buffer tank (60) is transferred into the negative pressure flash tank (20) for spray flash evaporation, the gaseous light components obtained by spray flash evaporation are transferred into a washing tower (70) for treatment, the liquid components obtained by spray flash evaporation flow back into the buffer tank (60) for heat compensation and then are circularly spray flash evaporated until the sulfur content of the liquid crude sulfur in the buffer tank (60) reaches a preset value to form the liquid refined sulfur, wherein the relative pressure in the negative pressure flash tank (20) is maintained between-50 kPa and-60 kPa.
4. The method according to claim 3, wherein the distillation and distillation combined device (30) comprises a distillation heating kettle (31) and a distillation tower (32) which are stacked, the liquid refined sulfur is gradually preheated to 320-330 ℃ by the heat exchanger (40), then automatically flows into the distillation heating kettle (31) and is gasified, the high-purity sulfur vapor is formed after rising through the distillation tower (32), a part of the high-purity sulfur vapor in a high-temperature state is conveyed to the heat exchanger (40) to release latent heat for preheating the liquid refined sulfur, then is mixed with another part of the high-purity sulfur vapor in a high-temperature state and is conveyed to the condenser (90), and the high-purity liquid sulfur is formed after liquefaction, and is conveyed into the high-purity solid sulfur made by the slicer (100) and is recovered.
5. The method according to claim 4, characterized in that a water ring vacuum pump (80) communicated with the negative pressure flash tank (20) is used for manufacturing a negative pressure environment in the negative pressure flash tank (20), gaseous light components sprayed and steamed out in the negative pressure flash tank (20) are conveyed to a washing tower (70) through a first waste gas recovery pipeline (106) for tar recovery treatment, and gaseous light components separated out by the high-purity sulfur steam in a high temperature state by releasing latent heat at the heat exchanger (40) are conveyed to a position of the first waste gas recovery pipeline (106) which is positioned at a downstream position of the water ring vacuum pump (80) for merging and conveying to the washing tower (70) for tar recovery treatment.
6. The method for purifying and recovering high-purity sulfur according to claim 3, wherein when the sulfur content of the liquid crude sulfur in the buffer tank (60) is 98% or more, the liquid purified sulfur is fed into the distillation and distillation combined device (30).
7. The method for refining and recycling high-purity sulfur according to claim 1, wherein in the step S1, the sulfur foam is primarily separated by a separator (13) in the continuous sulfur melting kettle (10), the sulfur foam is three-phase separated into an upper clear liquid layer, a middle tar slag layer and a bottom liquid crude sulfur layer by utilizing weight difference of each component, wherein the supernatant liquid of the upper clear liquid layer is subjected to a reflux desulfurization process system, the tar slag of the middle tar slag layer is discharged into a slag discharge groove (120) for recycling, and the liquid crude sulfur formed by the bottom liquid crude sulfur layer is conveyed into a discharge heat preservation groove (50) with the temperature maintained between 120 ℃ and 160 ℃ and then conveyed into the negative pressure flash tank (20).
8. A high purity sulfur refining recovery system for realizing the high purity sulfur refining recovery method according to any one of claims 1 to 7, comprising: The continuous sulfur melting kettle (10) comprises a shell (11), a sulfur melting cavity (12) surrounded by the shell (11) is internally provided with a separator (13) for three-phase separation of sulfur foam, the bottom of the shell (11) is provided with a discharge port (14), and the upper part of the shell (11) is also provided with a clear liquid discharge port (15); The negative pressure flash tank (20) is communicated with a discharge hole (14) of the continuous sulfur melting kettle (10), a negative pressure environment is formed in the negative pressure flash tank (20), and a flash evaporation spray header (21) is arranged in the negative pressure flash tank so as to purify the liquid crude sulfur separated from the three phases of sulfur foam into liquid refined sulfur; Distillation and rectification combination device (30) and heat exchanger (40), heat exchanger (40) set up negative pressure flash tank (20) with distillation and rectification combination device (30) between, distillation and rectification combination device (30) are including superimposed distillation heating cauldron (31) and rectifying column (32), negative pressure flash tank (20) extremely first liquid sulfur pipeline (101) of distillation heating cauldron (31) are through heat exchanger (40), and first gas sulfur pipeline (102) of rectifying column (32) also are through heat exchanger (40) are in order to utilize liquid refined sulfur inflow distillation heating cauldron (31) gasification after formation high-temperature state's high-purity sulfur steam's at least a portion latent heat be liquid refined sulfur preheats.
9. The high purity sulfur refining recovery system of claim 8, wherein the high purity sulfur refining recovery system further comprises: The continuous sulfur melting kettle (10) is sequentially arranged between the continuous sulfur melting kettle (10) and the negative pressure flash tank (20), a discharge port (14) of the continuous sulfur melting kettle (10) is communicated with a feed port of the discharge heat preservation tank (50) through a second liquid sulfur pipeline (103), a discharge port of the discharge heat preservation tank (50) is communicated with a feed port of the buffer tank (60) through a fourth liquid sulfur pipeline (104), a discharge port of the buffer tank (60) is communicated with the flash spray head (21) through a flash pipeline (105), the first liquid sulfur pipeline (101) comprises a preheating feed liquid branch (111) and a preheating discharge liquid branch (121), the preheating feed liquid branch (111) is communicated with the flash pipeline (105) and the heat exchanger (40) and is provided with a first flow control valve (201) thereon, the preheating discharge liquid branch (121) is communicated with a feed port of the heat exchanger (40) and the distillation heating kettle (31), and the negative pressure flash circulation tank (131) is arranged between the flash tank (20) and the flash tank (60); The device comprises a washing tower (70) and a water ring type vacuum pump (80), wherein the washing tower (70) is communicated with the negative pressure flash tank (20) through a first waste gas recovery pipeline (106), the water ring type vacuum pump (80) is arranged on the first waste gas recovery pipeline (106), the heat exchanger (40) is communicated with the washing tower (70) through a second waste gas recovery pipeline (107), and a connection point of the second waste gas recovery pipeline (107) and the first waste gas recovery pipeline (106) is located between the water ring type vacuum pump (80) and the washing tower (70).
10. The high purity sulfur refining recovery system of claim 8, wherein the high purity sulfur refining recovery system further comprises: The condenser (90) and the slicer (100) are sequentially arranged at the downstream of the discharge port of the rectifying tower (32), the feed port of the condenser (90) is communicated with the heat exchanger (40) through a second gas sulfur pipeline (108), the outlet of the condenser (90) is communicated with the slicer (100) through a sulfur recovery pipeline (109), and the slicer (100) is used for condensing the high-purity sulfur steam into high-purity solid sulfur and slicing and recovering the high-purity solid sulfur; and the slag discharge groove (120) is communicated with a slag discharge port formed in the bottom of the shell (11) and is used for recycling tar slag obtained by three-phase separation of sulfur foam.

Description

Refining recovery method and refining recovery system for high-purity sulfur Technical Field The invention relates to the technical field of industrial byproduct sulfur recovery and refining, in particular to a high-purity sulfur refining recovery method and a refining recovery system. Background Wet desulfurizing of coal gas is a widely used coal gas purifying technology in coking, petrochemical, chemical fertilizer and other industries, and a great amount of sulfur foam byproducts are produced in the process. The sulfur foam has complex components and contains water, desulfurizing liquid, catalyst, tar impurities which are difficult to treat, and the like in addition to sulfur. At present, in the coking and chemical fertilizer industries, how to improve the precision of purifying sulfur in sulfur foam generated in a coal gas wet desulfurization process to form high-purity sulfur within a certain energy consumption cost range is always a difficult problem puzzling the industries for many years. In the prior art in the industry, the sulfur foam treatment and recovery processes are many, but none of them is very ideal, and all have certain disadvantages. The most common sulfur foam treatment and recovery process mainly adopts a sulfur melting kettle to heat and melt sulfur foam, so as to realize the primary recovery of sulfur. However, the purity of the sulfur recovered by the method is low, generally only about 90%, and the recovered product is rich in organics such as tar, has black color, poor quality and low economic benefit. The existence of tar is easy to cause scaling and blockage of subsequent pipelines and equipment, and affects the long-term stable operation of the system. In order to improve the quality of the recovered sulfur, some technologies attempt to refine by high temperature gasification or distillation. However, if crude sulfur containing tar is directly treated at high temperature, the tar is easily cracked and coked at high temperature, and the distillation kettle and the rectifying tower are seriously blocked, so that continuous production is difficult to maintain. In addition, the high temperature rectification process is huge in energy consumption, and a large amount of latent heat generated during steam condensation is not effectively recovered, so that the production cost is high. Therefore, developing a high-purity sulfur refining recovery method and a high-purity sulfur refining recovery system which can effectively remove tar and recover high-purity sulfur, avoid the blockage of process system equipment, simultaneously realize energy conservation and consumption reduction, and stably operate within a reasonable energy efficiency range becomes a technical problem to be solved in the field. Disclosure of Invention The invention mainly aims to provide a high-purity sulfur refining and recycling method and a refining and recycling system, which are used for solving the problems of low precision of sulfur foam treatment, purification and recycling of sulfur, huge energy consumption of a purification and recycling process and unstable operation of a process system in the prior art. In order to achieve the above object, according to one aspect of the present invention, there is provided a method for refining and recovering sulfur from sulfur foam produced by a wet desulfurization process, comprising the steps of S1, transferring the sulfur foam produced by the wet desulfurization process into a continuous sulfur melting kettle to perform preliminary separation to obtain liquid crude sulfur, S2, transferring the liquid crude sulfur into a negative pressure flash tank to flash-remove light components therein to purify the liquid crude sulfur to form liquid refined sulfur, S3, transferring the liquid refined sulfur into a distillation and rectification combination device to perform high-temperature distillation gasification and rectification deep purification to form high-temperature high-purity sulfur steam, and S4, transferring at least a part of the high-temperature high-purity sulfur steam through a heat exchanger to preheat the liquid refined sulfur by using at least a part of latent heat thereof, condensing the high-purity sulfur steam to form high-purity solid sulfur, and recovering the high-purity solid sulfur. Further, in the step S2, the liquid crude sulfur is conveyed into a negative pressure flash tank for spray flash evaporation, gaseous light components obtained through spray flash evaporation are pumped out of the negative pressure flash tank by negative pressure and conveyed to a washing tower for treatment, and the liquid components obtained through spray flash evaporation form liquid refined sulfur. Further, in the step S2, conveying the liquid crude sulfur into a buffer tank with the temperature maintained between 150 ℃ and 160 ℃, conveying the liquid crude sulfur in the buffer tank into a negative pressure flash tank for spray flash evaporation, conveying gaseous light