XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3819
B
m
mt
1000^m
r
t r =
-h (2)
Additionally, the specific mass and lamerality of the ore
were determined, the latter being defined as the fraction
of oblong-shaped particles present in the ore. To this end,
particles with a length greater than three times the smallest
dimension present in a 300 g sample of crushed ore (grain
size between 10 and 13 mm) were separated and weighed.
Since it was desired to test the replacement of part
of the FERBASA comminution circuit with an HPGR,
an objective granulometric curve (target) was defined,
based on the specification of chromite sand production
(Figure 2). In this product, the presence of fines (–140#,
or passing at 110 µm) cannot exceed 2%, for contractual
purposes. Therefore, d80 =550 µm and d20 =130 µm were
adopted for the HPGR product. With the test results in
hand, Metso’s Bruno simulation software was used to simu-
late the industrial operating condition of the HPGR.
RESULTS
The specific mass found was 3.26 g/cm3, with an appar-
ent density of 1.81. The humidity found was 2.84%. The
Work Index (Wi) found was 14.67 kWh/t and the Bond
abrasion index (Ai) was 0.235. The Macon abrasion index
Table 2. Operating conditions adopted in the tests with the
Metso HRC D1000
Operational Variable
Value Adopted
in Tests
Initial pressure (N/mm2) 2.0
Operating pressure (N/mm2) 2.4
Initial gap (mm) 10.0
Operating gap (mm) 19.4
Circuit type Closed
Closing mesh (mm) 1.0
Figure 1. Simplified flowchart of the chromite sand (concentrate) production process at FERBASA
B
m
mt
1000^m
r
t r =
-h (2)
Additionally, the specific mass and lamerality of the ore
were determined, the latter being defined as the fraction
of oblong-shaped particles present in the ore. To this end,
particles with a length greater than three times the smallest
dimension present in a 300 g sample of crushed ore (grain
size between 10 and 13 mm) were separated and weighed.
Since it was desired to test the replacement of part
of the FERBASA comminution circuit with an HPGR,
an objective granulometric curve (target) was defined,
based on the specification of chromite sand production
(Figure 2). In this product, the presence of fines (–140#,
or passing at 110 µm) cannot exceed 2%, for contractual
purposes. Therefore, d80 =550 µm and d20 =130 µm were
adopted for the HPGR product. With the test results in
hand, Metso’s Bruno simulation software was used to simu-
late the industrial operating condition of the HPGR.
RESULTS
The specific mass found was 3.26 g/cm3, with an appar-
ent density of 1.81. The humidity found was 2.84%. The
Work Index (Wi) found was 14.67 kWh/t and the Bond
abrasion index (Ai) was 0.235. The Macon abrasion index
Table 2. Operating conditions adopted in the tests with the
Metso HRC D1000
Operational Variable
Value Adopted
in Tests
Initial pressure (N/mm2) 2.0
Operating pressure (N/mm2) 2.4
Initial gap (mm) 10.0
Operating gap (mm) 19.4
Circuit type Closed
Closing mesh (mm) 1.0
Figure 1. Simplified flowchart of the chromite sand (concentrate) production process at FERBASA