The authors, jointly and separately have been involved in various aspects of a number of membrane treatment plants: as researchers in laboratory and pilot scale investigations, as advisors in the design phase, and as consultants over operating problems or equipment failure. The major portion of this experience has been related to effluent treatment installations. In the course of these investigations we have observed (and sometimes perpetrated) a variety of situations which led to avoidable operating problems. This paper attempts to draw some general conclusions from these experiences, in the form of a set of guidelines, followed by some practical examples which highlight the relevance of some of the points which are raised.

Membrane separations have great potential in effluent treatment, but inherent in their power is their fragility. To harness the power, we have to protect the fragility from both chemical and mechanical abuse. In face of the uncertainties and contingencies of effluent treatment, this is a difficult task, and it is inevitable that progress will be accompanied by mistakes. It is essential that we assimilate and disseminate the information gained from these experiences.