FIG. 1.
Nickel sulfide concentrate biooxidation in two continuous cultures of moderately thermophilic acidophiles. (A) The reactors were operated at 49°C; one was gassed with CO2-enriched air (reactor 1) and one with air (reactor 2). The indicated mineral feed concentrations and residence times are for both reactors. The indicated time is that from inoculation of the reactors. (B) One of the reactors was maintained at 49°C (reactor 2), while the temperature in the other was increased gradually from 49 to 57.5°C (reactor 1). Both reactors were gassed with CO2-enriched air from day 270.