Comportamento do sistema de lodo ativado sob condições estacionárias em regiões tropicais.

Abstract

The activated sludge process is, today, the most widely applied system for biological watse water treatment. In regions with cold or temperate climates removal of biodegradable organic material from waste waters has been remarkably efficient. By contrast in Brazil, where seve ral activated sludge plants are in operation, performance has been unsa tisfactory. The weak performance appears to be due to inadequate design criteria for the locally prevailing conditions. In the present work it is attempted to make a contribution to the development of an activated sludge theory, applicable to tropical regions. The contribution is res tricted to modelling of the removal of organic material from the influ ent, sludge growth and oxygen consumption, in a completely mixed activa ted sludge process under constant flow and load conditions. A bench scale activated sludge system was operated at a temperatura of 28°C and at various sludge ages: 3, 10, 20 and 30 days. Based on the experimental results a model for the activated sludge system is presented that describes quantitatively the behaviour of the completely mixed activa ted sludge process insofar as effluent quality, sludge production and oxygen consumption is concerned.