This work presents an innovative approach on aerobic activated sludge (AS) wastewater treatment plants’ (WWTP) design and operation towards more efficient wastewater treatment, minimization of sludge accumulation and significant reduction of excess sludge, with relatively low specific energy consumption. This approach, which is called complete solids retention activated sludge (CRAS) process, was applied on a slaughterhouse’s WWTP and on a fruit processing industry’s WWTP, characterized by high organic and volumetric load respectively, as well as on a municipal WWTP located in Paralimni, Cyprus. The results showed without using sophisticated technologies and processes a more sustainable WWTP operation can be achieved.
