Studies of the Fouling of Heat Exchanger Equipment

Abstract

The fouling of heat exchanger equipment has long been one of the most troublesome, and unpredictable aspects of heat exchanger operation. In this thesis the nature of fouling is discussed, and the effect of a fouling film on a heat transfer surface is illustrated by numerical example. The various types of fouling are classified and comments on the factors affecting fouling are included. Problems related to the economics, design and maintenance of heat exchanger equipment subject to fouling are also discussed. After these introductory comments, a comprehensive literature survey is presented which concludes with a general discussion on the papers. A section describing the experimental work follows in which, first of all, the reasons are given for the choice of the experimental programme. This programme concerned the deposition of calcium sulphate on a heated surface, and was aimed at establishing a law relating the deposition rate both.to the heat flux causing the deposition and to the mass flowrate of the circulating solution. The experimentally derived law is subsequently applied to the analysis of a double-pipe heat exchanger in order to predict a thermal resistance-time relationship in both parallel flow and counter flow configurations. The thesis concludes with a discussion summarising the main points established in the body of the report and making recommendations concerning future researches.