738 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
as shown in Figure 7, the rheological characteristics of the
cake improved significantly. The result is a manageable,
non-thixotropic cake achieved without a cake-blowing step.
Figures 8 and 9 present the results for gold tailings
sample #2, both without and with this technology. Figure 8
demonstrates a significant reduction in filtration time, from
25 minutes to under 3 minutes. Figure 9 indicates that this
decrease in filtration time does not negatively affect the
cake quality. A decrease in cake-specific gravity and cake
dryness is observed. Both cakes are obtained by filtering on
recessed 50 mm without blowing.
IRON ORE TAILINGS DEWATERING
WITH TNS™ TECHNOLOGY
The evaluation of the impact of TNS technology was con-
ducted collaboratively by the EPA and a prominent techni-
cal service provider specializing in filtration. The screening
tests took place at the facilities of this major service pro-
vider. The material chosen for the test was slime tailings,
referred to as “Rejectados Ultrafinos,.”
Iron ore tailings tested consisted of slimes only at 37%
by mass solids concentration (P80 of 18.8 μm Fe content of
35% and pH of 8.5). Additional tailings tested consisting
of 80:20 flotation tailings a combination with slime tailings
at 65% by mass solids concentration.
Iron Ore Slime Filtration
The slime’s moisture content decreased from an average of
68% to 23% in all samples treated with TNS at two dif-
ferent dosages. Without treatment, no cake formed after 35
min. of form time while a cake developed after 5.5 and 6.5
min. in the treated samples (Details in Table 4.)
Figure 10 shows the pressure filter cake of slimes treated
with this technology, note the brittle dry cake. These treated
cake samples could be disposed of in a geo-stable deposit on
a mine site thus reducing the need for some fluid tailing
storage.
FINDINGS Copper Tailings
Even when operating at elevated flocculation solids
concentrations and with lower reagent dosages, the
new chemistry facilitates considerably faster consoli-
dation of the thickener bed, resulting in higher solids
loading rates and the attainment of greater thickener
underflow solids concentrations.
The TNS chemistry shows acceptable solids load-
ing rates, even at higher than optimum flocculation
solids concentrations, while still utilizing relatively
low reagent dosages.
Figure 7. Gold Sample #1—compare cake quality
Figure 8. Gold Sample #2—impact of TNS™ on filtration
time
Figure 9. On the left is the cake obtained without TNS™ on
the right is the cake obtained with TNS™
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Extracted Text (may have errors)

738 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
as shown in Figure 7, the rheological characteristics of the
cake improved significantly. The result is a manageable,
non-thixotropic cake achieved without a cake-blowing step.
Figures 8 and 9 present the results for gold tailings
sample #2, both without and with this technology. Figure 8
demonstrates a significant reduction in filtration time, from
25 minutes to under 3 minutes. Figure 9 indicates that this
decrease in filtration time does not negatively affect the
cake quality. A decrease in cake-specific gravity and cake
dryness is observed. Both cakes are obtained by filtering on
recessed 50 mm without blowing.
IRON ORE TAILINGS DEWATERING
WITH TNS™ TECHNOLOGY
The evaluation of the impact of TNS technology was con-
ducted collaboratively by the EPA and a prominent techni-
cal service provider specializing in filtration. The screening
tests took place at the facilities of this major service pro-
vider. The material chosen for the test was slime tailings,
referred to as “Rejectados Ultrafinos,.”
Iron ore tailings tested consisted of slimes only at 37%
by mass solids concentration (P80 of 18.8 μm Fe content of
35% and pH of 8.5). Additional tailings tested consisting
of 80:20 flotation tailings a combination with slime tailings
at 65% by mass solids concentration.
Iron Ore Slime Filtration
The slime’s moisture content decreased from an average of
68% to 23% in all samples treated with TNS at two dif-
ferent dosages. Without treatment, no cake formed after 35
min. of form time while a cake developed after 5.5 and 6.5
min. in the treated samples (Details in Table 4.)
Figure 10 shows the pressure filter cake of slimes treated
with this technology, note the brittle dry cake. These treated
cake samples could be disposed of in a geo-stable deposit on
a mine site thus reducing the need for some fluid tailing
storage.
FINDINGS Copper Tailings
Even when operating at elevated flocculation solids
concentrations and with lower reagent dosages, the
new chemistry facilitates considerably faster consoli-
dation of the thickener bed, resulting in higher solids
loading rates and the attainment of greater thickener
underflow solids concentrations.
The TNS chemistry shows acceptable solids load-
ing rates, even at higher than optimum flocculation
solids concentrations, while still utilizing relatively
low reagent dosages.
Figure 7. Gold Sample #1—compare cake quality
Figure 8. Gold Sample #2—impact of TNS™ on filtration
time
Figure 9. On the left is the cake obtained without TNS™ on
the right is the cake obtained with TNS™

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