LV Classifier and its unique seperation concept The principle of classification is same for all the classifier but what makes LV classifier unique is its three phase classification compared to single phase classification in modern classifier.
1st phase classification
The first phase classification takes place right at the feeding point, the coarse and grits fall down in the air stream and shall go back to mill for further grinding via reject air slide. This separation saves a lot in term of pressure drop across the separator as well power consumption. The grits get separated from the fines before reaching LV pockets and rotor (2nd and 3rd phase classification).
2nd phase classification
The second phase classification takes place in LV pockets due to velocity change and needs no energy to do that. This second phase classification removes a significant amount of coarse material before reaching the rotor for final separation. The 1st and 2nd phase classification reduces dust load going to the rotor and in return gives
- Low power consumption
- Low pressure drop
- High separation efficiency
3rd phase of classification
Third phase of classification takes place at rotor. As most of the coarse is already separated in feeding point and LV pockets, the rotor has much less work to accomplish and consequently the separation efficiency is the maximum possible in present range of separator.
One of the main criteria for better separation efficiency is also the even distribution of material throughout the static and rotor vanes,the LV classifier fulfills this requirement.Material is fed to the bottom of the classifier and is evenly distributed by the air stream. This ensures equal and even dust load at all the static and rotor surface area.
Traditional Modification of Ball Mill Classifier
The traditional way of classifier modification is by replacement of low efficiency classifier with high efficiency classifier.
- High production.
- Low specific power consumption.
- High classifier efficiency.
- High cement strength.
- Better particle size distribution.
- Preferable size distribution of product.
- Higher investment cost.
- Longer payback period.
- Longer shutdown time.
- Risk in terms of quality and production.
As we know that a separator is not a machine which grinds the material but basically it separates the material coming from mill. If we assume that the mill grinding efficiency is good then the classifier is low efficient when, we have a lot of fine material going in reject which in fact should go as product.
This means our basic aim is to get out some more fines from the separator reject and there by improving the separation efficiency and mill grinding efficiency.
This leads to increase in production and reduction in specific power consumption.
To satisfy the basic aim LV Technology has developed the concept of "Differential Particle Separation Concept" called the DPS concept which ensures the removal of fines from reject and as well remove the inherent disadvantages of traditional system of modification.
DPS Concept of separation
In DPS concept the existing separator remains the same, the reject from the existing separator goes to small new LV classifier, the fines are collected in cyclone or bag filter ( as desired by client) and the reject from this separator goes back to mill. Apart from the advantages of traditional classifier modification this concept has some extra advantages which are listed below,
- Very low investment cost.
- Almost No stoppage time required for modification.
- Zero risk in terms of production and quality.
- Very-very short payback period.
- Very easy erection.
Besides our own design of the classifier for Vertical Roller Mills, L. V. Technology today has the unique design of a ball mill classifier, a high efficiency cyclone with low pressure drop, a new concept of calciner by pass design and Nox reduction technology, these items allow the company to offer improvement to the complete production line of a cement plant.