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Working in a production plant aromatics. The unit of liquid-liquid extraction using sulfolane as a solvent. High corrosion rates are presented and are now breaking equipment. Successful cases could help me with this problem and problem of corrosion in sulfolane?

Additional info: Thanks for your answer. Actually we have a problem with oxigen in water system. The primary solvent( wet) is black color and foaming. whitout suspended solids. What best practices have been applied to detect and remove the air inlets in the vacuum system?
 
Answers
19/12/2013 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
To find air leaks, apply soap foam, or other foams to the flanges.
14/12/2013 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
Better solvents such as NMP are available to get rid of corrosive problems caused by sulfolane. Number of plants have switched over to extract benzene by NMP
11/12/2013 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
For extraction of aromatics better non corrosive solvents are now being used at many plants
10/12/2013 A: Lindsay McRae, Pall Corporation, Lindsay_McRae@pall.com
Corrosion is a fact of life in sulfolane plants. Therefore a good filter on the solvent loop is essential to continuously remove the corrosion products that are generated to prevent foaming of the solvent plus also to prevent fouling in pump seals, columns and heat exchangers.
We have seen excellent results replacing strainers, nominal type filters or bagfilters with absolute rated filters. Often this can be a direct retrofit of existing housing but sometimes the housing may need to be modified or replaced also.
Utilising 10um absolute (@ 99.98% efficiency filter compared to 10um nominal ( @ 90% efficiency) will make a big improvement to solvent cleanliness level and aromatics plant operation and reliability. Often existing solvent filters may be too course in micron rating, sometimes not sealing properly or perhaps operating on too small a slipstream flow. I can provide some further information on case studies if you need it.
09/12/2013 A: Marcello Ferrara, ITW SrL, mferrara@itwtechnologies.com
We have developed a specific program to solve the problem. Please contact me.
09/12/2013 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
Sulfolane decomposes in the presence of oxygen, and the products of the decomposition are corrosive. Oxygen can inter the unit in the feed. To prevent that requires a well-designed and well-functioning gas blanket on the feed tank. Oxygen can also enter the system in the vacuum section of the process, through leaks.