XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 183
before about 30% of the whole material was separated as
barren rock by sensor-based ore sorting from a fraction of
10/60 mm particle size. The resulting pre-concentrate was
used as feed material for the tests described herein.
METHODOLOGY
Sample Material
About 150 t of ore were recovered from the Tellerhäuser
deposit and primary crushed on a jaw crusher. After clas-
sification, the fractions 10/30 mm and 30/60 mm were sent
to sensor-based sorting. The pre-concentrate was shipped
to the test facilities of the Institute for Mineral Processing
Machines and Recycling System Technologies (IART),
where the secondary crushing tests were conducted. As
shown in Figure 2, after pre-screening and sorting, there
was hardly any fine fraction left.
The various lithologies found in the Tellerhäuser
deposit were thoroughly investigated by Quantitative
Microstructural Analysis (QMA), point load test (PLT),
Mineral Liberation Analysis (MLA) etc. Figure 3 shows
thin sections of the skarn wall rock, investigated with opti-
cal microscopy. The respective QMA data are indicated
in Table 2. For material characterization, a compressive
strength of σD,IS(50) =128 MPa (parallel to foliation) was
determined.
Setup for the Test
Impact stresses are often considered to be particular sup-
portive for Selective Comminution (Hesse 2017). Höffl
indicates a minimum impact speed vP,min for particles to be
crushed or disintegrated in a macroscopic manner acc. to
the eq. (1) (Höffl 2006):
Figure 1. Impressions from the Hämmerlein and Tellerhäuser deposits: (a) „Tin chamber“, remnant from test mining in the
1980s, currently open for visitors (b) Sphalerite bearing vein
(a) (b)
Figure 2. Feed material for the tests, left: fraction 10/30 mm right: fraction 30/60 mm
before about 30% of the whole material was separated as
barren rock by sensor-based ore sorting from a fraction of
10/60 mm particle size. The resulting pre-concentrate was
used as feed material for the tests described herein.
METHODOLOGY
Sample Material
About 150 t of ore were recovered from the Tellerhäuser
deposit and primary crushed on a jaw crusher. After clas-
sification, the fractions 10/30 mm and 30/60 mm were sent
to sensor-based sorting. The pre-concentrate was shipped
to the test facilities of the Institute for Mineral Processing
Machines and Recycling System Technologies (IART),
where the secondary crushing tests were conducted. As
shown in Figure 2, after pre-screening and sorting, there
was hardly any fine fraction left.
The various lithologies found in the Tellerhäuser
deposit were thoroughly investigated by Quantitative
Microstructural Analysis (QMA), point load test (PLT),
Mineral Liberation Analysis (MLA) etc. Figure 3 shows
thin sections of the skarn wall rock, investigated with opti-
cal microscopy. The respective QMA data are indicated
in Table 2. For material characterization, a compressive
strength of σD,IS(50) =128 MPa (parallel to foliation) was
determined.
Setup for the Test
Impact stresses are often considered to be particular sup-
portive for Selective Comminution (Hesse 2017). Höffl
indicates a minimum impact speed vP,min for particles to be
crushed or disintegrated in a macroscopic manner acc. to
the eq. (1) (Höffl 2006):
Figure 1. Impressions from the Hämmerlein and Tellerhäuser deposits: (a) „Tin chamber“, remnant from test mining in the
1980s, currently open for visitors (b) Sphalerite bearing vein
(a) (b)
Figure 2. Feed material for the tests, left: fraction 10/30 mm right: fraction 30/60 mm