ABSTRACT
The advent of natural gas from the North Sea has brought about the cessation of commercial gas manufacturing from coal and oil in the UK. It has not, however, ended the interest which the gas industry has in gas purification processes. Over the years, various technologies such as chemical absorption, physical adsorption, direct conversion and cryogenic separation have been developed for the purification of gases. These technologies can require large, complex plant and can be expensive to operate and maintain. Much effort is therefore being directed at improving separation techniques throughout the chemical industry. Over the last dozen years, membrane technology has been developed to the stage that the separation of gases using semi-permeable polymer membranes has become both technically and economically viable and membrane separation units have been operating on many chemical plants around the world. In comparison with the conventional technologies listed above, membrane technology seems to offer a simple, easy to operate, process which has no moving parts and requires a minimum of maintenance. British Gas, in common with other sectors of the chemical industry, has been studying the growth of membrane technology and its possible applications. Within British Gas we envisage that the principal use to which membrane separation would be put would be in the treatment of natural gas, especially at the production wellhead. There are several main areas in which membrane separation might be considered for possible application, and these are discussed below.
