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CN-122006290-A - Stable operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption

CN122006290ACN 122006290 ACN122006290 ACN 122006290ACN-122006290-A

Abstract

The invention relates to the technical field of stabilization operation of aromatic hydrocarbon extraction solvents, in particular to a stabilization operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption. According to the invention, the core film forming agent concentrated solution, the first aqueous sulfolane dispersion liquid, the cerium source concentrated solution and the second aqueous sulfolane dispersion liquid are sequentially added into the lean solvent main line, and a stable protective layer is formed on the metal surface through progressive interface reaction design of opening-repairing-sealing, so that the vicious circle of solvent degradation and equipment corrosion is effectively cut off, the sulfolane acid discoloration and corrosion are obviously inhibited, the regeneration energy consumption is reduced, and the method is suitable for the stable operation of a sulfolane arene extraction device.

Inventors

  • XIE FUJIAN
  • Wang Mengmin
  • GUO FANG
  • WEI YUNTAO
  • Liang Xundong
  • Ni Yunlian
  • LI HUA
  • ZHANG YUNFEI
  • CHEN MING
  • CHU YANXU

Assignees

  • 山东森之海新材料有限公司

Dates

Publication Date
20260512
Application Date
20260413

Claims (10)

  1. 1. A stabilized operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption, comprising the steps of: Maintaining the circulating sulfolane of the device in a normal running state, continuously adding a core film forming agent concentrated solution into a lean solvent main line between an outlet of a reboiler and an inlet of a lean-rich solvent heat exchanger, after the core film forming agent concentrated solution is added, introducing the circulating sulfolane of the device from a lean solvent side line, cooling, adding deionized water to form a first aqueous sulfolane dispersion, and then reinjecting the first aqueous sulfolane dispersion into the lean solvent main line; The core film forming agent concentrated solution is prepared from sulfolane and silane functional imidazoline film forming agent; The silane functional imidazoline film forming agent is obtained by the reaction of tridecanoic acid, pentadecanoic acid and a silane coupling agent Silquest A-1120; The cerium source concentrated solution is prepared from cerium octoate and sulfolane; The amount of water added to the second aqueous sulfolane dispersion is less than the amount of water added to the first aqueous sulfolane dispersion.
  2. 2. The stabilized operation method according to claim 1, wherein the mass fraction ratio of the silane-functionalized imidazoline film forming agent to sulfolane is 10-14:86-90.
  3. 3. The stabilized operation method according to claim 1, wherein the mass fraction ratio of tridecanoic acid, pentadecanoic acid and silane coupling agent Silquest A-1120 is 86-129:97-145:229.
  4. 4. The stabilized operation method according to claim 1, wherein the reaction is continued for 3 hours under reduced pressure of 25 to 30kPa at 170 to 180 ℃ after the reaction is first incubated at 140 ℃ for 2 hours.
  5. 5. The stabilized operation method according to claim 1, wherein the mass fraction ratio of the cerium octoate to the sulfolane is 16-20:80-84.
  6. 6. The stabilized operation method according to claim 1, wherein the core film former concentrate is added in an amount of 4000 to 4500g for 90 to 120min in 10000kg of the apparatus circulating sulfolane.
  7. 7. The stabilized operation method according to claim 1, wherein after 75-90min of the core film former concentrate is added in 10000kg of the plant circulating sulfolane, 40-60kg of the plant circulating sulfolane is led out from the lean solvent side line and cooled to 40 ℃, 600-900g of deionized water is added to form the first aqueous sulfolane dispersion.
  8. 8. The stabilized operation method according to claim 1, wherein the cerium source concentrate is added in an amount of 600 to 840g based on 10000kg of the apparatus circulating sulfolane.
  9. 9. The stabilized operation method according to claim 1, wherein the second aqueous sulfolane dispersion is formed by introducing from the lean solvent side line 15 to 25kg of the apparatus circulating sulfolane and cooling to 40 ℃ after 20 to 30 minutes from the start of the cerium source concentrate addition, based on 10000kg of the apparatus circulating sulfolane, and adding 200 to 300g of deionized water.
  10. 10. The stabilized operation method according to claim 1, wherein the core film former concentrate is again added after the continuous stabilized operation for 48-72 hours after the completion of the first film formation operation, and thereafter the cerium source concentrate is added every 7-10 days.

Description

Stable operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption Technical Field The invention relates to the technical field of stabilization operation of aromatic hydrocarbon extraction solvents, in particular to a stabilization operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption. Background Sulfolane as one excellent polar solvent has wide application in arene extracting, gas purifying and other petrochemical fields. In long-term industrial applications, the problem of sulfolane degradation is always a key factor affecting long-term stable operation of the device. The prior researches show that sulfolane is easy to generate hydrolysis and oxidation reaction under the condition of the existence of moisture and oxygen, and acidic byproducts such as sulfonic acid, sulfuric acid esters and the like are generated. These acidic substances not only can increase the chromaticity rise and quality degradation of sulfolane solvent, but also can form serious corrosion threat to common equipment materials such as carbon steel, stainless steel and the like. Especially in the high temperature loops such as the bottom of the regeneration tower, a reboiler, a lean-rich solvent heat exchanger and the like, the local temperature can reach more than 160 ℃, and the acid corrosion and the thermal stress are mutually overlapped, so that the area becomes a high-incidence part of corrosion failure of the whole device. Corrosion products such as iron ions further enter the solvent system, which in turn catalyzes the sulfolane degradation reaction, forming a vicious circle of solvent degradation-equipment corrosion-further solvent degradation. In response to the above problems, common measures in industry include providing a solvent regeneration unit to remove part of the acidic degradation products by intermittent or continuous regeneration, periodically replenishing fresh sulfolane into the system to dilute the degradation components, and cleaning or replacing severely corroded equipment during equipment downtime. However, these methods are essentially post-remediation strategies, i.e. intervention is not performed until corrosion and solvent degradation have occurred and reached a certain severity. They have difficulty cutting the chain from the source, which is continuously deteriorated on the metal surface. For example, even if the bulk acid number is reduced by regeneration, the already formed iron oxide domains and active sites on the walls of the equipment continue to catalyze localized degradation of the solvent and induce localized corrosion such as pitting, which is particularly pronounced on the high temperature heat exchanger and reboiler tube bundle surfaces. Therefore, there is a need to develop a stabilized operation method capable of actively constructing a stable protection layer at a metal/solvent interface to thereby cut off corrosion and degradation links. Disclosure of Invention In view of the above, the present invention aims to provide a stable operation method for inhibiting the acidic discoloration and corrosion of sulfolane extractant and reducing energy consumption, so as to solve the problems of high equipment corrosion rate, large solvent chromaticity amplification and high regeneration energy consumption caused by the difficulty in effectively cutting off the vicious circle of continuous induction of solvent degradation and corrosion aggravation of the metal surface active site in the existing sulfolane device regeneration loop. Based on the above object, the invention provides a stabilized operation method for inhibiting acid discoloration and corrosion of sulfolane extractant and reducing energy consumption, which comprises the following steps: Maintaining the circulating sulfolane of the device in a normal running state, continuously adding a core film forming agent concentrated solution into a lean solvent main line between an outlet of a reboiler and an inlet of a lean-rich solvent heat exchanger, after the core film forming agent concentrated solution is added, introducing the circulating sulfolane of the device from a lean solvent side line, cooling, adding deionized water to form a first aqueous sulfolane dispersion, and then reinjecting the first aqueous sulfolane dispersion into the lean solvent main line; The core film forming agent concentrated solution is prepared from sulfolane and silane functional imidazoline film forming agent; The silane functional imidazoline film forming agent is obtained by the reaction of tridecanoic acid, pentadecanoic acid and a silane coupling agent Silquest A-1120; The cerium source concentrated solution is prepared from cerium octoate and sulfolane; The amount of water added to the second aqueous sulfolane dispersion is less than the amount of water added to the first aqueous sulfolane dispersion. The core film forming agent co