Q & A > Question Details
What is WSIM for ATF ?
How will it affect the product performance/ quality??
What are the measures to be taken to control WSIM ?
25/06/2018 A: Sudhakara Babu Marpudi, Dangote Oil Refinery Company, m_sudhakarababu@yahoo.com
Water separometer Index Modified (WSIM), is the indicator water separability of ATF. Caustic entrained with ATF from the ATF reactor is washed off in water wash vessel. In the process, wash water picks up alkali traces, and high pH water needs to be drained off regularly. Water traces entrained with ATF, from wash water vessel is absorbed into rock salt in the Salt filter. The absorbed water need to be drained off regularly from the salt filter. ATF will fail WSIM test, if 1) water level in the salt filter is high (not drained off till clear ATF is observed at the drain point, 2) Salt level is low (as the salt gets dissolved in ATF product), 3) wash water pH is high (water replacement not regular), 4) High wash waterintrainment with ATF (volume of ATF is higher than the capacity of wash water vessel. It is necessary to check all these points and apply correction wherever required to ensure that ATF meets the WSIM limits.
20/06/2018 A: Sridhar Balakrishnan, Bharat Oman Refineries Limited , laksrid@yahoo.com
WSIM is modified name of MSEP . It is called Water Separaometer Index Method . Some of the compounds if present in Jet A-1 like surfactants, particulates, corrosion inhibitors . These will improve water retaining properties of the fuel , hence can cause corrosion , also microbiological induced corrosion. Water present in fuel if it enters engine can clog the fine filters. Clay treater section in Merox or Merichem units of refinery removes above components from ATF . WSIM test detect carryover of refinery treating residues in fuel as they are produced. They can also detect surface active substances added to or picked up by the fuel during transportation.