A chrome flowsheet should connect the feed mineralogy to a saleable product specification. A drawing that shows a scrubber and spirals without this connection is only an equipment arrangement.
Feed grade and liberation
Head grade indicates the amount of chromite but not whether chromite is liberated from gangue. Locked particles may require size reduction, while already liberated material may need only washing and classification.
Clay and ultrafines
Clay can bind particles and disturb the flow in gravity equipment. Fine liberated chromite may also occur in the slime fraction, so desliming should be evaluated with size-by-size assays rather than treated as automatic waste removal.
Product specification
Target Cr2O3 grade, Cr/Fe ratio, size range and impurity limits determine how much cleaning is required and how much mass can report to concentrate.
Roughing and cleaning balance
Spiral roughing may produce a heavy fraction, a middling and a tailing. Re-treating every middling stream can increase circulating load without improving the final product. The circuit should recycle only streams with a demonstrated benefit.
Water return and tailings
High slurry volumes need practical dewatering and water return. The cost and area required for tailings can determine whether a nominally successful laboratory route is workable at site.
A useful test program reports concentrate grade, recovery, mass pull and results by size fraction. These values allow equipment sizing to follow the process rather than precede it.