How to choose crusher in coal preparation plant
The basic requirements of the coal preparation plant for the crusher:
On the premise of ensuring the discharge particle size, over-grinding should be reduced as much as possible, so as not to increase the burden on the slime water system. For coking coal preparation plants, the increase in the amount of slime will increase the cost of flotation; for thermal coal preparation plants, the increase in the amount of slime will bring disastrous consequences to the dehydration of the slime.
Comparison of several crushers
Since the jaw crusher, hammer crusher and impact crusher all have the phenomenon of over-crushing, unless the above-mentioned special cases (such as when the coal contains large-sized pyrite nodules), the The above three types of crushers should be avoided as much as possible.
At present, the most used in the design is the toothed roller crusher and the classification crusher. The classification crusher is completely different from the traditional toothed roller crusher which is crushed by impact and extrusion, but makes full use of the characteristics of compressive strength>shear strength>tensile strength of coal and other materials. At the same time, the linear speed of each contact point between the material and the roller teeth is different, so the crushing operation has a certain impact, which is also conducive to the crushing of the material.
Classifying crusher is used in coal preparation plant and has the following outstanding advantages:
⑴Because of the use of low speed and special tooth shape, the crushing tooth structure is actually like a rotating grid screen, and the particles smaller than the discharge size can pass directly without crushing, so the material is less over-crushed and over-material.
(2) If the system adopts effective iron and wood removal measures, the raw coal can be directly classified and crushed without pre-screening, thus simplifying the technological process.
Therefore, the coal preparation plant should give priority to the classification crusher when choosing the crusher.