Figure 1. Diagram of the system for generating a biofilm of Thiobacillus thioparus. (1) Bioreactor; (2) Flowmeter; (3) Sensor of pH; (4) Heater; (5) Peristaltic pump; (6) NaOH; (7) Liquid culture medium; (8) Glass columns packed with the carriers; (9) Effluent accumulation.