Pronab Maintaining temperature below 120 deg cent - one reason could be loss of inhibitor in MDEA at higher temperature and faster degradation of MDEA.. When temperature is < 120 deg cent inhibitor in MDEA functions better with lesser chances of degradation. In other wrods beter protection for vessel components at lower temperatures < 120 deg cent. Velocity limit for C.S in amine service : to my knowledge - is preferable to maintain at less than 1-2 m / sec ( i.e., at 3-7 ft / sec). At higher velocities 10-20 ft/sec ( 3-6 meter/sec) C.S will erode faster + inhibitor loss in MDEA. Normally S.S materials withstand velocity of flow of 3-6 m/sec (10-20 ft/sec) in amine service and not Carbon steel. Are you sure API 571 guidelines stipulate for carbon steel this high velocity in MDEA and amine service towres or piping? Even for straight lengths - for C.S- 10-20 ft / sec velocity and flow in amine service will erode piping components. In tray segements in towers, with higher velocity, tower will see impingemnet erosion - corrosion in amine service. Preferntial erosion -corrosion may occur at bottom segements with higher velocity flow at 10-20 ft./sec for Carbon steel. Trust this helps you C.V.Srinivasan Nishi Engineers Pvt Ltd India June 20, 2007 E-mail: nishi@vsnl.com >M.S. DuPart et al., stated in the paper on %E2%80%9CUnderstanding >corrosion in alkanolamine gas treating plants%E2%80%9D published >in Hydrocarbon Processing on May 1993, in an amine plant >regenerator bottom temperature should be maintained less >than 124 Deg. C, which he repeated another paper on >Corrosion 2000, Paper No 00499 %E2%80%9CCorrosion in alkanolamine >plants: Causes and minimization%E2%80%9D. But in our gas >sweetening plants (3 Units, using MDEA solvent) regenerator >bottom temperature are maintaining 131 Deg. C without >considerable amounts of amine degradation and corrosion >problems. Also he mentioned that solution velocity should be >limited to 3 ft/sec ( in fact 3 %7E 7 ft/sec) for CS while as >per API-571 recommended 10 to 20 ft/sec. >Can anyone please clarify these differences? >Regards. >Pronab.

By mistake I write in MDEA system there is inhibitor, actually there is no inhibitor use in MDEA system for corrosion protection. MDEA itself is a good corrosion resistant. Sorry for this mistake. Regards.