After screening, the pulp was transferred to a 2.5 L JK batch flotation cell and then conditioned with collector (90 g/t) and frother
(130 g/t) at an agitation speed of 700 rpm. The solid percentage in
the flotation cell was about 15% which is consistent with the plant
condition. The flotation pH was constant about 9.0 when saline
water was used due to the buffer effect of saline water. When
de-ionised water was used, NaOH solution was used to justify
the flotation pH at 9.0. When flotation commenced, four concentrates were collected after cumulative times of 1, 2.5, 5, and
10 min with an air flow rate of 2.0 L/min. The flotation froth was
scraped every 15 s. Flotation products were combusted at 815 C
for 2.5 h to obtain the ash and combustible contents