Mining Process Solutions
Mining Process Solutions
Design Features of Sensor Based
Separators
There are still technics where
coarse-grained ores are enriched by hand today. Sensor based separation
equipment is an important alternative to manual seperating (sorters)
management.
In mining, it is essentially
necessary to extract the waste grains from the ore or to divide the ore into
two groups as high and low grade.
For this reason, the development of
the optical (photometric) separators, radiometric separators produced for use
in enriching uranium or gold / uranium ores and magnetic separator sensors are
followed. These are followed by the production of microwave, laser-induced
fluorescent (laser induced fluorescence) and similar sensors in the following
years. When evaluated in terms of commercial success, sensor-based separator
applications produced based on the photometric (optical) principle are the most
popular processes in the industry.
All sensor-based separators generally have a common design and are produced for different processes. This design consists of a light source selected depending on the sensor, a monochromator if necessary, and a sensor for detecting light reflected or absorbed through the material. The light source can be natural light, deuterium arc lamps, infrared lamps, tungsten filament lamps, led lamps, IR sources depending on the sensor.
Components and Functions of Sensor
Based Separators
Sensor-based separation systems
consist of four basic components:
Supply system
Reporting the material to the system
Identification system
Separation system
Supply System
In the sensor based separation
systems, the notification of the material to be supplied and separated to the
system is important in terms of achieving a high separation efficiency. The
grains pass through the feed before it enters the sensor's field of view
(reported to the system). The design of the feed trough should be done in such
a way as to control and fix the fastness of the grains in the material. In this
way, behaviors such as jumping, bouncing, shielding each other or deviating in
its orbit will be prevented. In this sense, the ideal grain behavior is that
the grains leave the supply chamber at the belt speed if the supply is carried
out with tape.
Sample Preparation
The points to be considered while
preparing the sample vary according to the type of material and the subsequent
enrichment steps, if any. It must meet operational requirements in the process
from the supply conveyor to separation. The most important issue is the ratio
of the largest to the smallest of the grains in the supply to the 3: 1 or 2: 1
border as much as possible. This empirical approach prevents performance drops
caused by large grain sizes. In general, the feeding method in the narrow grain
size range is valid for other methods of ore enrichment. In any system where
the surface properties are distinguished, the original surfaces of the grains
must be dedusted so that they can be detected by the sensor.
Identification Systems
Identification systems consist of a
sensor and light source. Depending on the intended use, the sensors can be
sensitive to conductivity, monochromatic, visible light (color), infrared or
near infrared (IR / NIR) light. Light sources are also chosen as fluorescent,
NIR or LED depending on the sensor used. The sensor can be placed under or
across the supply belt to see the point where the feeding system ends and the
grains enter the identification area.
Using Sensor Based Separator
Sensor-based ore separator
technology began to spread rapidly in Turkey. The separators, which entered the
market in the 1970s by identifying black and white with the camera system and
separating the material into two, are very popular today in the food,
recycling, special products and mining sectors.
