【Haichuan’s Best Practices】Adding an amine solution purification system to the desulfurization unit to improve desulfurization efficiency
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Jinling Petrochemical: Amine liquid purification system improves desulfurization efficiency 2019-02-13 Source: Sinopec News Network Print article Petrochemical news Recently, the newly installed amine liquid purification system at Jinling Petrochemical has shown significant results. Operational data indicate that after purification, the concentration of thermally stable salts in the desulfurization solvent decreased from 14% to 2.34%, thereby enhancing the efficiency and safety of the desulfurization system. The desulfurization solvents used in the desulfurization systems of Units 2 and 3 in the company’s Refining Department 2 have, after prolonged operation, accumulated a large amount of unwanted impurities and thermally stable salts. These accumulated thermally stable salts can cause a range of problems, including equipment corrosion, solvent foaming, ammonia loss, substandard quality of the refined products, and high steam consumption in the regeneration towers, thereby severely affecting the stable operation of the units. To solve this problem, the company installed amine solution purification systems for Desulfurization Units 2 and 3 to purify the desulfurization solvents. Nearly 7 months of purification efforts have shown that the concentration of thermally stable salts in the desulfurization solvents has been reduced by 83 percentage points, yielding significant results. Currently, the regeneration towers of the two desulfurization units are operating safely and stably, and the quality of the purified products is continuously improving. (Chen Pingxuan Li Shengyang)
Thermally stable salts affect the safe operation of the solvent regeneration system and tend to cause foaming
The main problems plaguing refineries are the high concentration of hydrocarbons in the solution, as well as the formation of amine solutions due to organic acids, which causes foaming in the contact towers and stripping towers. This leads to solvent loss, poisoning of the sulfur regeneration catalysts, and a reduction in the contact efficiency. Liquid hydrocarbons, FeS/SS, chemical treatment agents, etc., present in the raw natural gas cause scaling in condensers and heat exchangers, reducing efficiency; they also cause severe corrosion of the heat exchange surfaces, leading to damage to thermal equipment. Frequent replacement of the amine solution for filtration, the formation of heat-stable salts, the generation of cyanides, scaling of the activated carbon filtering medium, increased use of thermal energy, the need to replenish solvents, and an increase in wastewater treatment all contribute to rising maintenance costs. The causes of foaming include hydrocarbons and organic acids, which lead to foaming in amine solutions. Properly treated fluids and corrosion inhibitors, oils, inhibitors, and welding fluids; water contaminants; suspended solids; improper selection of filtration materials. It is crucial to maintain a clean system. The concentration of hydrocarbons can be reduced by controlling the flow rates of amine-water lean solutions and natural gas. Natural gas should be thoroughly filtered to reduce liquid hydrocarbons, FeS/SS, as well as chemical treatment agents. Sufficient activated carbon and mechanical filtration are necessary, along with the proper selection of mechanical filtration materials. Anti-foaming agents can be used temporarily
1. Raw gas filtration: Before amine cleaning, the solid and liquid impurities present in the raw gas must first be removed. Feichao uses coagulators for filtration to effectively trap solid and liquid impurities such as rust and iron sulfides. 2. Amine recovery: The use of coagulators enables the recovery of the amine contained in the gas, preventing losses of this amine and thus avoiding increased operating costs. 3. Reducing foaming in amine solutions: Polypropylene FSH filters with high dirt-holding capacity are used for filtering rich/amine-poor solutions to remove solid particles; subsequent passage through activated carbon filters eliminates gases present in the amine solution, thereby preventing issues such as foaming in downstream equipment. 4. Technical support for cleaning systems: The SelfClear○R rapid cleaning system is the best solution for dealing with large amounts of viscous, deformed substances and fine particles in liquid streams ；
The cleanliness of the amine solution plays a significant role in determining the proper operation of the desulfurization system; this is a fundamental requirement. It seems a bit absurd to try to show off this aspect as if it were something worth highlighting!
Does the poster mean they have just installed a new amine liquid purification system? Still providing amine solution purification services
It should be an additional amine liquid purification device; the operating costs for this must be quite high. We have to commission external firms to carry out the purification process once a year