Answer:
6 stages
Explanation:
Given:
Copper ore contains:
4.3 wt% water
10.3 wt% CuSO₄
85.3 wt% rock
Feed rate = 11.7 tons per hour
solution produced is to be 10 wt% copper sulfate
90 wt% water
Now,
The CuSO₄ supplied through the feed = 10.3 wt% CuSO₄ × Feed rate
= 0.103 × 11.7
= 1.2051 tons per hour
also,
At each stage 2 tons of solution is collected
therefore,
The CuSO₄ collected in each stage
= weight of solution × 10 wt% copper sulfate
= 2 tons per hour × 0.1
= 0.2 tons per hour
also,
98% of the CuSO₄ is to be recovered
thus,
the amount of CuSO₄ to be recovered
= 0.98 × CuSO₄ supplied through the feed
= 0.98 × 1.2051 tons per hour
= 1.180998
Therefore,
The number of stages required =
=
= 5.90499 ≈ 6 stages