Page 245 - Gas Purification 5E

Mechanical Design and Operation of Alkanolamine Plants 231

salts, inadequate amine solution regeneration, etc.) should be identified and corrective
actions should be implemented.
4. Amine solution is opaque black, objects cannot be seen through the bottle, and substantial
sediment has settled out of the solution after ten minutes. In this case, the amine system is
probably becoming severely fouled with suspended solids and immediate corrective action
is required.

CHEMICAL LOSSES
Volatility Losses

Amine volatility losses are usually not significant. DEA, DIPA, DGA, and MDEA all
have very low vapor pressures at typical amine contactor and regenerator operating condi-
tions. However, MEA has a substantially higher vapor pressure than other amines, and
volatility losses in low pressure MEA contactors can be significant. In some cases, a water
wash is provided for low pressure MEA contactors (See Chapter 2). Figure 3-20 can be used
to estimate amine volatility losses.

10
SO
2D
I .o

05
a2
I"
I 0.i
I
0.05
=1
v)
v)
% 002
a
5 0.01
a
4
0.005
ol302
mol
a0005

0.0002
QOOOI
50 70 90 110 I30 I50
TEMPERATURE,OF
Figure 3-20. Vapor pressure of rnonoethanolamine and diethanolamine over aqueous
solutions. Chemetron Corporation and Texaco Chemical