XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2093
1991). Although the fluvial deposits are less rich in total
HMs compared to the shoreline placer deposits, the fluvial
deposits are constantly renewed through annual transport
of ~8 × 108 tonnes of sediment (Coleman 1969). The high
sediment volumes choke the river systems, which also serve
as major transport routes in Bangladesh, and annual dredg-
ing is required to maintain open waterways. Capturing and
recovering valuable HMs from waste dredge material is
therefore a potentially cost-effective, long-term source of
HMs provided the materials meet market specifications.
During the initial stages and pre-feasibility of any ore-
body evaluation, the primary purpose of a pilot plant is to
produce heavy mineral concentrate for metallurgical evalu-
ation and since 2022 the Institute of Mining, Mineralogy
and Metallurgy (IMMM) of BCSIR has operated a HM
pilot plant in Joypurhat to assess and process material
from the northern Brahmaputra River. The current study
presents preliminary results from the pilot plant follow-
ing characterisation studies on selected product streams
to determine the compositions of the heavy minerals
present and to assess the effectiveness of the separations.
The samples were characterised by analytical techniques
including X-Ray Fluorescence (XRF) spectroscopy, X-Ray
Diffraction (XRD) and Electron Probe Microanalysis
(EPMA). Emphasis is placed on characterising the valu-
able components of the HM sand fraction including the
TiO2-rich content of the HM concentrate to provide an
assessment of potential ilmenite processing options, and
the garnet component for possible refractory use.
METHODS
Raw Materials
A 5500 kg bulk sand sample from the margins of a river
stable sand bar and the adjacent riverbed was collected by
means of a floating mechanical dredge equipped with a
rotating cutter suction head. The dredging site was in the
upstream part of the southward flowing Brahmaputra River
near Chilmari riverport, Kurigram. The dredged site has a
length of 300 m and a width of 100 m, of which 50 m is
on the bar and 50 m is within the riverbed. The GPS coor-
dinates of the dredging site were between 25°33'29.99"N
to 25°33'39.69"N latitude and 89°41’16.86”E to
89°41'18.37"E longitude. The dredging site location is
shown in Figure 1.
Figure 1. Location of the dredging site
1991). Although the fluvial deposits are less rich in total
HMs compared to the shoreline placer deposits, the fluvial
deposits are constantly renewed through annual transport
of ~8 × 108 tonnes of sediment (Coleman 1969). The high
sediment volumes choke the river systems, which also serve
as major transport routes in Bangladesh, and annual dredg-
ing is required to maintain open waterways. Capturing and
recovering valuable HMs from waste dredge material is
therefore a potentially cost-effective, long-term source of
HMs provided the materials meet market specifications.
During the initial stages and pre-feasibility of any ore-
body evaluation, the primary purpose of a pilot plant is to
produce heavy mineral concentrate for metallurgical evalu-
ation and since 2022 the Institute of Mining, Mineralogy
and Metallurgy (IMMM) of BCSIR has operated a HM
pilot plant in Joypurhat to assess and process material
from the northern Brahmaputra River. The current study
presents preliminary results from the pilot plant follow-
ing characterisation studies on selected product streams
to determine the compositions of the heavy minerals
present and to assess the effectiveness of the separations.
The samples were characterised by analytical techniques
including X-Ray Fluorescence (XRF) spectroscopy, X-Ray
Diffraction (XRD) and Electron Probe Microanalysis
(EPMA). Emphasis is placed on characterising the valu-
able components of the HM sand fraction including the
TiO2-rich content of the HM concentrate to provide an
assessment of potential ilmenite processing options, and
the garnet component for possible refractory use.
METHODS
Raw Materials
A 5500 kg bulk sand sample from the margins of a river
stable sand bar and the adjacent riverbed was collected by
means of a floating mechanical dredge equipped with a
rotating cutter suction head. The dredging site was in the
upstream part of the southward flowing Brahmaputra River
near Chilmari riverport, Kurigram. The dredged site has a
length of 300 m and a width of 100 m, of which 50 m is
on the bar and 50 m is within the riverbed. The GPS coor-
dinates of the dredging site were between 25°33'29.99"N
to 25°33'39.69"N latitude and 89°41’16.86”E to
89°41'18.37"E longitude. The dredging site location is
shown in Figure 1.
Figure 1. Location of the dredging site
