FLOWSHEETS Zinc Plant Flowsheet (SOMINCOR)

Analysis of flowsheets SIMPLE CASE final concentrate final tailing

Balance of each node input parameters: α,, Input data concentrate C1 semiproduct P1 concentrate C2 α feed concetrate tailing calculated parameteres: , ,  r, a…  – content of a component in feed %, – content of a component in concentrate, %,  – content of a component in combined products, %, – content of a component in tailing, % GRADE  – yield of a product, %  – recovery of a considered component in a product, %  r – recovery of other than considered components in another product, % Grade Concentrate *Tail* Selectivity feedconcentratetailingyieldrecovery α νγεεrεra Node #%%% * ,  and  r calculated from α,,

EQUATIONS (%) (-) a = 100 ideal separation, a ~ 1000 no separation

Flowsheet with balances of nodes (local balances) product grade,% yield,% recov., % C feed tailing T concentrate C1 concentrate C2 concentrate C3 F P P C C T

Upgrading curves for nodes using local balances conclusion: separation is best in node 1 (a= and worse in nodes 2 and 3, a=~125)

Best flotation results upgrading curve EQUATIONS for instance for products C1+C2 Product rr  r C C C T F1.42 weighted average

Global balance of flowsheet

Options of industrial flowsheet Feed tailing T final concentrate C f semiproduct P1 semiproduct P2 concentrate C2 concentrate C3 final tailing T f concentrate C1 4

= Feed tailing T final concentrate C f semiproduct P1 semiproduct P2 concentrate C2 concentrate C3 final tailing T f concentrate C Feed final concentrate C f semiproduct P1 semiproduct P2 final tailing T f =

1 2 3 Feed tailing T final concentrate C f semiproduct P1 semiproduct P2 concentrate C2 concentrate C3 final tailing T f concentrate C1 4

1 2 3 Feed tailing T final concentrate C f semiproduct P1 semiproduct P2 concentrate C2 concentrate C3 final tailing T f concentrate C1 4 5

1 2 3 Feed tailing T final concentrate C f semiproduct P1 semiproduct P2 concentrate C2 concentrate C3 final tailing T f concentrate C1 4

Selectivity of separation for different options of composition of final flotation products =

Selection of optimum point of process common sense optimum point of separation example of point of optimum separation based on economics Final decision: Cf=C1+C2 + something depending on criterion of upgrading optimal point

Transformation of the Fuerstenau(recovery-recovery or  -  ) upgrading curve into Halbich (grade-recovery or β-  ) upgrading curve the Fuerstenau (  -  ) is alfa -insensitive equivalent of the Halbich ( β-  ) upgrading curve

FLOWSHEET WITH A RECYCLE STREAM

Flowsheet with balance of nodes (local balances) input parameters: α,,

EQUATIONS (%) (-) a = 100 ideal separation, a ~ 1000 no separation Recycle node (1) Separating nodes 

node 2  r 0,00 100,00 25,000,89 28,40 99,33 0,5799,11100,0071,60100,000,00 0,78 4  r 0,00 100,00 25,0011,76 52,63 90,65 3,0088,24100,0047,37100,000,00 5,59 5  r 0,00 100,00 0,6078,48 83,30 21,55 0,4421,52100,0016,70100,000,00 0,57

Upgrading curves for nodes using local balances node 5 is not efficient

Global balance of flowsheet (feed F2 is 100%) Eqs for recycling nodes known parameters: α,,

Calculations Feed 1: grades are known,  G and  G are equal to 100% Node 1 Grades are known, local  and  for F1 are known (  =21.95%) (for C3 is =78.05%) or can be calculated from grades of products Calculation of global  for F2 Q) How large is  for C3 when for F1 is 100%? A) When  F1 =100%,  C3 =(100/21.95)x 78.05= 350%. Then  F2 =  F1 +  C3 = =450%

Calculation of  for recycling node (here F2):

Calculation for (normal) separation nodes

Graphical representation of separation data (not very useful, recoveries greater than 100%) Grade –recovery curve for Pb, Cu and Zn circuits within the Eureka Concentrator (based on Ch. Greet, Spectrum Series, 2010)

Some flowsheets can be complex

The Eureka Mine – An Example of How to Identify and Solve Problems in a Flotation Plant Christopher Greet

PublicationsPublications : Spectrum SeriesSpectrum Series Flotation Plant Optimisation: A Metallurgical Guide to Identifying and Solving Problems in Flotation Plants Spectrum Series 16 Published in 2010 The Eureka Mine – An Example of How to Identify and Solve Problems in a Flotation Plant Christopher Greet Useful literature

Homework Create your own flowsheet and calculate local and global balanses as well as plot graphs which will help you to evaluate the plant performance