Preamble

An important aspect of any mineral processing study is an analysis of how material is distributed whenever streams split and combine. This knowledge is necessary when a flow sheet is being designed and is also essential when making studies of operating plants.

In this lecture basics of material balance in mineral processing is discussed.

Material balance

It is based on the principle of conservation of matter. In general

                                                                                               
In a continuous system at steady state, there is no accumulation and hence

Input=output

In mineral processing operations, single input of feed (ore) produces a concentrate containing most of the valuable and the tailing containing gangue minerals. Thus

Tons of feed  Tons of concentrate  + and tons of tailing

(2)

(3)

   
Let f is fraction of metal in feed, c and t are fraction of metal in concentrate and tailing respectively, then

(4)

By 3 and 4 we can obtain

(5)

Plant recovery (R)is

(6)

                                                                                                 
By 5 and 6 we get

(7)

                                                                                                             
In lecture on measurements of quantities we derived the relationship between percent solids   and pulp densities, when water is used as a medium to make the pulp, (pulp and slurry are synonyms).

(8)

                                                                                                                
 of solid and  = density of slurry

Mass flow rate of dry solids in pulp (slurry)

(9)

                                                                                                                         
 and  

(10)