Fill cycle begins

1. Polyprep Continuous Reagent Make-up and Dosing Plant The concept typically provides for a 3 compart-ment tank, which creates separate zones for wet-ting, maturing and dosing. The entire procedure after first fill is sequenced and attuned to customer specification allowing for the following set-up as shown by the animation: When the dosing zone reaches a minimum level as indicated by level-switch 1, the hopper feeder / wethead discharges into the wetting zone with the reagent emulsion, which overflows into the maturing zone where it displaces matured reagent to the dosing zone. The sizing of the plant provides for total dissolution of powder reagent by the time the dosing zone is reached. The maximum level in the tank is determined by level-switch 2 which stops the feed. The floc wethead flushes for an additional thirty seconds after stopping the hopper feeder thus preventing clogging. Mixers 1 and 2 continuously stir the emulsion to optimise dissolution. The sequence is initiated whenever the minimum level (level switch 1) is reached. “Continuous Make-up and Dosing” allows for a larger volume to be made up in comparison to what is dosed on average. Reagent and water feed rates are individually adjustable to change the concentration if required. YOU NEED LESS THAN HALVE THE TANK CAPACITY OF CONVENTIONAL PLANTS 2 1 30sec stop delay Level switch 1 on Alarm Sounds Fill cycle begins Level switch 2 on Sequencehalted Magra Process Engineering (Pty) Ltd Phone: +27 18 468 1540 Fax: +27 18 468 - 8492 Cel: +27 82 372 3404 e-mail wallie@magra.co.za Provisional Patent no. 2001/4659 Control Panel Hopper Feeder Mixer 1 Mixer2 Dosing Zone Maturing Zone Wetting Zone Dosing Tank Low Press Escape to Stop

2. VERTICAL BAFFLE PLATE INCLINED BAFFLE CONCEPT The inclined downstream baffle design of the Polyprep reagent make-up and dosing plant prevents carry-over of undissolved solids particles from one zone to the other. The baffles form between them a conduit of increasing cross-sectional area. This has the effect that the velocity of the rising solution decreases within the conduit as the liquid flows upwardly between the baffles. The entrained undissolved particles sink downwardly when the downward settling characteristic of the particle is greater than the upward flow ve- locity. A point is reached where the rising velocity of the solution is sufficient to entrain the undissolved particle and once again carry it upwards. This sequence repeats itself and in the process the particles dissolve thereby minimizing carry over of undissolved particles from one zone to another. VIRTUALLY CLEAR OVERFLOW UNDISOLBED HEAVY PARTICLES INCLINED BAFFLE