Costs for membrane cleaning – an economic assessment

Cleaning is an inevitable, and often costly, part of most membrane filtration plants. The economic assessment of cleaning costs is often rather arbitrary when researchers design and estimate costs of a membrane plant in a new application. Severity of fouling, operation conditions, cleaning agents and cleaning frequency all influence the costs for membrane cleaning. In addition to the costs of the cleaning process itself, cleaning also affects membrane lifetime, membrane performance during filtration and process down time. The cleaning procedure and cleaning frequency varies from one application to another and most cleaning studies are therefore trial-and-error investigations. Temperature, time, concentration and type of cleaning agent must be adapted to the conditions in each individual application. Furthermore, in some cases it is necessary to use a sequence of different cleaning agents. The influence of cleaning conditions on costs for membrane cleaning is illustrated in this work.