Is it recommended to mix deliquescent desiccants together in a single dryer vessel to improve performance?
PROBLEM: It is not uncommon, especially during the winter months, for customers to want improved performance from their single tower deliquescent type dryer. To achieve this, a customer may add a more hygroscopic deliquescent desiccant to an existing desiccant bed. There is typically an immediate improvement in the provided dew point, but it is a short term solution which often results in channeling and caking in the desiccant bed as well as little performance improvement once the more hygroscopic desiccant is used up.
INDUSTRIES AFFECTED: sales gas, instrument gas, power generation.
SOLUTION: Instead of mixing two deliquescent type desiccants in a single desiccant bed, the better choice is to install two vessels in series. The first vessel using the less hygroscopic desiccant would reduce the gas water content to 33-50% RH. The second vessel using the more hygroscopic desiccant would act as a polishing type desiccant providing a 13% RH. The primary benefits are: guaranteed dew point performance, lower operating cost and maintaining desiccant bed integrity.
Does this apply to you? We are here to help. Contact us at 1-800-840-9906, we can help match you up with the correct desiccant for your application.