Secondary grinding

2. Part 01
Part 02
Part 03
Part 04
INTRODUCTION
MACHINE THAT USED
ADVANTAGES & DISADVANTAGES
OF PROCESS
STEPS OF PROCESS

3. § Secondary grinding in mineral
processing is the second stage of
size reduction, following primary
grinding.
§ The goal of secondary grinding is to
further reduce the size of the mineral
particles to the desired fineness,
which is typically in the range of 10
to 150 micrometers. This is done to
liberate the individual minerals from
each other and to prepare the
material for downstream processing
steps, such as flotation, leaching, or
smelting.
INTRODUCTION

4. § Secondary grinding is typically
carried out in a ball mill, which is a
rotating cylinder filled with steel
balls or grinding media.
§ The mineral particles are fed into
the mill and are ground by the
impact and attrition of the
grinding media.
§ The size of the grinding media and
the speed of rotation of the mill
are both important factors in
determining the fineness of the
ground product.
MACHINE THAT USED

5. • Secondary grinding circuits
are often closed circuit,
meaning that the discharge
from the mill is classified
and the coarser particles
are recycled back to the mill
for further grinding.
• This allows for more
precise control of the
product size and also helps
to improve the efficiency of
the grinding process.
MACHINE THAT USED

6. STEPS OF PROCESS
The secondary grinding process typically involves the following steps:
1. Material Preparation: The material to be ground is first prepared by removing any impurities or contaminants
that could interfere with the grinding process. This may involve washing, drying, or screening the material.
2. Feeding the Material: The prepared material is then fed into the grinding mill. The rate at which the material
is fed is carefully controlled to ensure that the mill is not overloaded and that the desired particle size is
achieved.
3. Grinding: The grinding media within the mill (typically balls, rods, or pebbles) are agitated using mechanical
energy, causing them to collide with and crush the material. The size of the grinding media and the intensity of
the agitation determine the final particle size.
4. Classification: Once the material has reached the desired particle size, it is classified or separated from the
grinding media. This is typically done using a screen or a classifier that separates the finer particles from the
larger ones.
5. Product Collection: The classified material, now with the desired particle size, is collected for further
processing or packaging.

7. Part 02
Part 03
Part 04
Gold and Silver mining Copper mining
Lead and Zinc mining Iron ore mining
Coal mining Phosphate mining
Industrial minerals processing
v The specific type of secondary grinding mill used
and the operating parameters will vary depending
on the mineral being processed and the desired
product size. However, the general principles of
secondary grinding are the same for all
applications.

8. Secondary grinding offers a number of advantages over primary
grinding, including:
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More precise control of
the product size.
Improved liberation of the
individual minerals
Reduced energy
consumption.
Increased grinding
efficiency.
ADVANTAGES OF PROCESS
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9. Secondary grinding also has some disadvantages, including
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Higher capital cost.
More complex process
control.
Increased operating
costs.
Overall, the advantages of secondary grinding typically outweigh the
disadvantages. Secondary grinding is an essential step in many mineral
processing operations and is required to produce a high-quality product.
DISADVANTAGES OF PROCESS
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