YFLM Superfine Vertical roller grinding Mill plant
The main unit of vertical mill is driven by decelerator , then take the grinding plate’s rotation, grinding rollers follow grinding plate for the friction, materials pass the feeder valve, first feeder conveyor, second feeder conveyor to the grinding plate’s center, with the centrifugal force, materials move to the edge of grinding plate, when reach the grinding track ,the materials are grinded between grinding roller and grinding plate, the grinding pressure is offered from stretch device of hydraulic cylinder. In the processing of grinding ,materials are got grinding plate’s pressure and shear force at the same time, after materials are been extruded ,from the material bed on the grinding track, then materials on the material bed extrude and rub together ,which cause the corner angle and margin’s desquamation, then grinding powder deeply. After grinding , the material continue to move the edge of grinding plate until overflow outside ,there are special design coulter at the edge of grinding roller, which can lead the material to grinding roller to extrude continually, grinding plate’s rim have induced air rings, the airflow from the high pressure air blower will take the powder from down to up with high speed, then enter to the classifier to control the fineness, the coarse powder drop back the grinding plate to regrind, if others can meet the requirement of fineness ,will collected by the duster collector and transmitted by the pneumatic transmission to warehouse, then packing it. The large particle will be discharged from the bleed hole, and then the material is taken back to the feeder system of grinder by the belt conveyor.
Process Flow Diagram:
Performance and Advantages:
1. Low cost of operation
(1) Use the rollers to grind the material directly, low consumption, it can save 30%～40% than ball mill.
(2) When the mill is operating, roller cannot touch the grinding plate directly, and the rollers and scaleboard are high quality, with long service life.
2. Environmental protection
When the mill is operating, roller cannot touch the grinding plate directly, it don’t have the crash voice, small shaking, low noise, it’s lower 20-25db than the ball mill machine. The vertical rollers use the omniseal system. Negative-pressure production is adopted, being environment-friendly and without dust pollution.
3. Easy operation and operation stably
(1)The machine has auto control system, remote control and easy operation. (2) It has the stop lock to prevent the cover of rollers touch the scaleboard of grinding plate directly and prevent the destroy impact and violent shake. (3) With the help of roll device, we can put the roller out of grinding plate to exam and change the cover of rollers and scaleboard.
4. High efficiency of drying
Vertical mill use hot wind to transmit material, when grind the high moisture material, we can control the inlet air temperature to make product meet the standard, the mill can dry material of 15% moisture, it’s used widely. The ball mill only can dry material of 3%-4% moisture.
5. High quality of product
Materials only stay 2-3 minutes in the vertical mill, but stay 15-20 minutes in the ball mill, so we can measure and adjust the chemical element and fineness fast, the product quality is steady.
YFLM1200 vertical roller mill specifications:
|Testing product||Superfine ground calcium carbonate|
|Specific surface area||cm2/g||11000±500||14000±500||15500±500||17000±500||19000±1000|
|325 mesh of residual volume||%||0.015||0.015||0.01||0.002||0|
|Less than 2um content||%||32||38||42||50||60|
|Average grain diameter: D50||um||4.5||3.2||2.4||2.0||1.4|
|General terms of market||mesh||600||800||1000||1500||2000|
|Cut point of grain size||um||49||42||35||28||18|
|Moisture||%||0.4 below||0.4 below||0.4 below||0.4 below||0.4 below|
1. Size distribution: use the particle size analyzer of MALVERN to testing.
2. Specific surface area: average grain size exchange. Unit is the relative area of 1g powder.
3. Average grain size: size distribution get the median of grain size.
4. 325 mesh residual: use the wet-type method to put the 1000g powder through 325 mesh screen, calculate the percentage.
5. Moisture: testing the 5g powder in the 150℃ within 6 minutes, measure the verification.
6. Grinding materials: limestone, calcite, dolomite, talc, barite, wollastonite, brucite, Calcium hydroxide, gypsum, coking coal, slag ,phosphate etc.