J. Mccarthy et Ma. Trebble, AN EXPERIMENTAL INVESTIGATION INTO THE FOAMING TENDENCY OF DIETHANOLAMINE GAS SWEETENING SOLUTIONS, Chemical engineering communications, 144, 1996, pp. 159-171
The foaming tendency of a 30 weight % solution of diethanolamine (DEA)
in distilled water was measured over a temperature range of 20-85 deg
rees C and a pressure range of .1-3 MPa in the presense of a number of
contaminants including carboxylic acids, oils, 1-4 bis (2-hydroxyethy
l) piperazine (HEP), methanol, iron sulphide, silicone antifoam, etc.
The measurements were conducted using a Jerguson high pressure sight g
lass contained in an air bath. Foaming was measured at gas rates up to
7.5 standard m(3)/d using air, nitrogen, carbon dioxide, and ethane.
One notable observation was that the addition of most of the contamina
nts commonly identified as foam promoters did not create a foaming sys
tem with a clean 30% DEA solution. In fact, the only solutes that prod
uced significant foaming were the carboxylic acids as noted previously
in the literature by Pauley et al. (1989). The addition of contaminan
ts to a foaming system did increase foam heights and stability substan
tially and results are presented for methanol and HEP addition to a fo
aming system of DEA-carboxylic acid. The effects of temperature, press
ure, and gas flow rates on foam heights and foam break times were meas
ured for a number of systems. Foaming was increased by a higher temper
ature and by higher pressure and was much more pronounced when carbon
dioxide or ethane gases were used.