For a flotation circuit, material balance calculations define an engineering problem where flow parameters between unit operations are partly known. The purpose of a material balancing is to mathematically examine the known flow parameters to solve for the unknown flow parameters. Two main types of material balances are commonly made:

• design material balance
• operating plant material balance.

The design material balance is typically faced during plant design when the flotation test work results and a flowsheet diagram are the only known values. Design material balance purpose is to find values for the unknown flow parameters.

Operating flotation circuits material balances contains large amount of data and helps produce a picture of the state of an operating plant. Here is a procedure of how to do balancing for an operating flotation circuit using Microsoft Excel Solver on Excel spreadsheet. An example solving a copper concentrator flotation circuit is presented and the process flow diagram is given below.