Analysis Of Foaming Mechanisms

Scientific & Technical Report
Analysis of Foaming Mechanisms
in Amine Plants
Presented by:
C. Richard Pauley
Pauley Gas Conditioning
Chattanooga, Tennessee
and
Reza Hashemi
Scott Caothien
Pall Corporation
East Hills, New York
to the
American Institute of Chemical Engineer’s Summer Meeting
August 22-24, 1988
Denver, Colorado

GDS120

Scientific & Technical Report
Analysis ofFoaming Mechanisms in Amine Plants
Presented by: C. Richard Pauley, Pauley Gas Conditioning, Chattanooga, Tennessee
and Reza Hashemi, Scott Caothien, Pall Corporation, East Hills, New York
To the: American Institute of Chemical Engineer’s Summer Meeting
August 22-24, 1988, Denver, Colorado

Table of Contents
1.0

INTRODUCTION....................................................………………………………………….…4

2.0

MECHANICS OF FOAM FORMATION AND STABILITY
2.1

Surface Tension & Foaming Tendency ...................................................................... 4

2.2

Elasticity of Film Layer & Foam Stability .................................................................... 4

2.3

Gelatinous Layer Formation & Hydrocarbon Solubility ................................................ 5

2.4Film Drainage & Foam Stability ....................................................................……….. 5

2.5

Iron Sulfide & Surface Viscosity ............................................................……………… 6

3.0

DATA & EXPERIMENTAL RESULTS ..............................................................……………….. 7

4.0

DISCUSSION OF RESULTS
4.1

Contaminants..................................................................................………………. 11

4.2

Foam Stability as an Indication of Problematic Behavior ..........................……….…. 11

4.3

Factors Influencing Foam Stability ..............................................................………… 11

4.4

Effect of Contaminants on Foam Stability ..................................................…….…...11

4.5

Contaminant Removal ............................................................................…………… 12

5.0

CONCLUSIONS ............................................................................................……………… 13

6.0

BIBLIOGRAPHY………………..………………………………… ........................……..……. 14

7.0

APPENDIX A – EXPERIMENTAL PROCEDURES AND APPARATUS
A.1Determination of Foaming Tendency and Stability .................................................... 14

A.2

Determination of Surface Tension ............................................................................ 15

A.3

Determination of Carbon Efficiency .......................................................................... 15

1.0 Introduction
Foaming in amine plants increasesoperating
costs and reduces treating efficiency. When foaming becomes severe, amine is often carried over
into downstream treating equipment. It is commonly held that liquid hydrocarbons and iron
sulfide cause foaming. Most treatments rely heavily on carbon filtration and the addition of
antifoam agents to the circulating solutions. 1,2
Unfortunately, most antifoam agents are surface
active,and are removed by activated carbon.
Most often, after a brief improvement the problem becomes worse.

Since pure amines do not form stable foams, one
or more components must be present in the
treating solution in order to form a persistent
foam.3 Possible contaminants include not only liquid hydrocarbons and iron sulfide, but well treating fluids, amine degradation products, and other
finelydivided solids. The purpose of this work
is to determine the physical/chemical mechanisms which cause foaming and offer some practical solutions to control the foaming.

2.0 Mechanics of Foam Formation and Stability
Foam is the result of a mechanical incorporation
of a gas into a liquid. The liquid film surrounds
a volume of gas creating a bubble. The formation...