Learning outcome

A candidate who has passed the course will have a learning outcome in the form of aquired knowledge and skills as described below.

Knowledge

The candidate is mastering advanced theory on mass transfer processes combined with chemical reactions and knows how gas treating or processing is practiced in the natgas and syngas industries.

Skills

The candidate is able to assess and calculate complex mass transfer transfer problems applied to gas treating

Course Description

The course will start with an overview that will cover the following: Treating of natural gas for pipe line transport, options for sulphur removal, current options for post-combustion CO2 removal, and gas separation techniques in general (a brief look).

Rate limited mass transfer between gas and liquid will then be discussed. Having established the basics of rate limited mass transfer, including the coupling with chemical reactions, the chemistry of absorption of CO2 and H2S into alkanolamine and carbonate solutions will then be discussed.

After reviewing these chemical reactions, the concept of absorption with chemical reaction will be developed further. It will be explained how the chemical reactions can speed up mass transfer while linking this to the chemistry taught in the preceding section. Mixed absorbents and so-called activators will be discussed in this context.

The subject matter will then be extended to include the influence of water transfer between the phases. This is particularly important in the desorption processes. Sensible heat transfer between gas and liquid will also be discussed along with the analogies by Reynolds and Chilton-Colburn.

Key aspects of the CO2 (and/or H2S) absorption process from gas will be discussed. These include the water balance and loss of chemicals to the environment. (Or rather what to do to avoid this).

A brief review of models for absorption equilibria and mass transfer coefficients will be given. The aim is to give the students a good start with respect to where to look, and some of the pitfalls in using the published models.

The course will be rounded off with a discussion of chemical degradation of the absorbent chemicals and how this is influenced by factors such as oxygen, more acidic gases, CO2(!), heat etc. A discussion of how process equipment design might influence such degradation will also be given.

Teaching and Learning Methods

Lectures and course work.

Assessment Methods

Examination at the end of the course, and a design exercise.

Minor adjustments may occur during the academic year, subject to the decision of the Dean