ABSTRACT
A solids balance (or mass balance) calculation is a comparison of the solids going into a process with those c 0 6 out. In other words:
I Solids In = Solids Out The secondary clarifier solids balance can be used to determine the return sludge rate (RAS rate) because Eturn sludge rate is one of the variables of the solids balance calculation, as shown in the expanded equation on the opposite page. Note this equation assumes that negligible solids leave the system in the clarifier effluent flow.
