Pneumatic flotation machines.
Pneumatic single-chamber flotation machines of column type are designed for ore dressing by froth floatation method and recommended to be used mostly for recleaning of floatation rough concentrates with solid content in the initial feed up to 40%, concentrating material fineness of more than 70% of class minus 0.074 mm, ore density up to 4.6 tons/m3 and feed flowrate up to 2.5 m3/min.
The association produces pneumatic machines with chamber capacity of 6 m3, 12 m3, 25 m3, 50 m3. As compared to impeller floatation machines pneumatic machines ensure increasing of useful component content in concentrate by 1-2%, increase in recovery by 0.5-2.5%; reduction of costs for repair, electrical power consumption by 40% and production area by 60%.
Floatation machines are equipped with an automatic system of pulp level stabilization.
Special features of the machines are:
• aerator with a special fabric hose that ensures forming of fine-dispersed air bubbles and protects them from clogging when the machine stops;
• airlift discharge of chamber product;
• system to supply washing water for froth spraying.
Pneumatic floatation machine is a chamber which is rectangular (Fig. 1) or round one in section (Fig.2) consisting of an upper section (1), three intermediate sections (2) and a lower section (3), equipped with a reception section (5), a discharge section (4), aerators (6), an airlift (7). In the upper part of the chamber, a spraying device (8) is installed, and in the lower part a hose gate (9) is installed to discharge the material completely from the chamber. In the upper section, there are froth overflow channels to collect and remove froth. The service life period is more than 3000 hours due to the fabric coating.
As compared to impeller floatation machines pneumatic machines ensure increase in useful component content in concentrate by 1 -2%, of recovery by 0.5-2.5%; reduction of costs for repair, electrical power consumption by 40% and production area by 60%.
An automatic pulp level stabilization system is installed on the pneumatic floatation machine to maintain the pulp level. The system:
• ensures high reliability of the pulp level control;
• allows visual monitoring of the current and preset pulp level values as well as fast change of controller task and settings;
• is fast acting and ensures smooth control of the pulp level;
• is long–life due to the pulp level sensor design not inclined to incrustation unlike float sensors and using of highly reliable automatic controller;
• allows stabilizing the pulp level with accuracy of ±50 mm when the pulp level changes in the range of 0 - 500 mm due to application of a high precise microprocessing controller.