Flocs: are the masses of bacteria associated with fungal filaments to form mesh like structure. It helps in aerobic decomposition, while filaments help in trading particles.
These microbes in the flocs consume the major part of the organic matter in the effluent and reduce the biological oxygen demand(BOD) of the effluent. Less BOD means the wastewater is less polluted. After this, the effluent is passed into the settling tank where the flocs are allowed to settle and this sediment is called Activated sludge.
A small part of activated sludge is pumped back to serve as the inoculum. Inoculum is the small amount of material which contains microbes that can start new culture. This way same microbial culture is recycled and reused to start a new culture for the treatment.
Rate this question :