UPGRADING OF A SMALL WASTE-WATER TREATMENT-PLANT - DESIGN AND OPERATION ASPECTS

This paper presents the case of a small wastewater treatment plant tak en out of service due to insufficient design and equipment installed. Design assumptions and decisions made for plant restoration based on t reatment requirements are outlined and plant operation aspects regardi ng revealed wastewater characteristics, process efficiency, sludge set tling behaviour and equipment control, are discussed. The importance o f wastewater characterization as a necessary procedure prior to plant design and construction, is stressed and the feasibility of nutrient r emoval in small wastewater treatment plants under minimum supervision, is assessed A simplified mathematical model, as a useful tool to oper ators, for plant performance evaluation and prediction, is presented.