Some of the processes modifications or variations of basi ses that have evolved to meet different and flowsheets processes used for BOD removal and nitrification. The according to the basic reactor configuration: plug-flow, complete-mix, and sequentially ab 7-/precription of activated sludge processes for BOD removal and nitritic sipes ascription Complete-mix la) Complete-mix activated-sludge(CMASH CMAS I low F/M ratios courage the growth af filamentous bacteria, cousing sludge bulking Pug-flow [b) Conventional plug Row and return activeted sludge(RAS)enter the front end the aeration system is dosigned to match the separated in a secondary settling tank ration(see conventional plug flow ification in which lw MLsS koop a stable protion. Adequate mixing and aeration 77-18 Some of the processes modifications or variations of basic processes that have evolved to meet different performance objectives. Descriptions and flowsheets are presented in Table 7-7 for representative processes used for BOD removal and nitrification. The processes grouped according to the basic reactor configuration: plug-flow, complete-mix, and sequentially operated systems. Tab 7-7 Description of activated sludge processes for BOD removal and nitrification Process Description