Technical Data

Grinding Plate Dia: 1200-2600(mm)

Main Motor Power(kW): 55-710

Applied material: coal, slag, clinker

Application: Pulverized Coal Grinding System, GGBS Grinding System

OUR ADVANTAGE

1. VRM can handle materials with sizes greater than 85mm

2. VRM mill can remove more than 20% moisture

3. Vertical roller mills plants use less space

4. Grinding plants VR mills have lower specific energy consumption (15-40%)

5. VRM are more flexible, the capacity can easily be varied from 40 to 100% of the nominal capacity

6. Lower noise level for VRM grinding plants

1

INTRODUCTION
2

SPECIFICATIONS
3

STRUCTURE

INTRODUCTION
Coal Vertical Roller Mill (VRM) is an air swept, medium-speed, vertical pulverizer with integral classifier. It pulverizes coal by applying hydraulically-loaded grinding pressure through three grinding roller onto a rotating bed of coal. Grinding pressure can be adjusted to account for variations in coal grindability and desired product fineness.

Vertical roller mill can replace ball mills or tube mills used for preparing coal. Today VRMs with capacities up to 50 tph are the dominant technology for coal grinding. Grinding media wear in a VRM will only be 5 to 10 g/ton of coal powder, as compared to 100 g/ton of coal powder in a ball mill.

Application:
The coal powder grinding system is mainly used for burner of burning system in cement plant, lime plant etc, which can also applied in making coal powder which are used for the boilers in power plant and thermal power plant.

Production Process Flow Chart
The raw coal is stored in the raw coal bunker and fed into the vertical mill by the belt weigher in bottom of raw coal bunker. After drying, grinding and powder classifying, the coarse coal powder with unqualified size will be fall down onto the millstone again for grinding. Meanwhile the qualified coal powder will be discharged with airflow, and entered into the high concentration bag filter especially for coal mill, the air cleansing by bag fiter will be exhausted into the atmosphere., The coal powder collected by the dust collector will be conveyed into coal powder silo through the conveyor belt. Any sundries inside the raw coal, like coal gangue, metal block, etc, will be discharged out of the mill by vane.

The coal powder prepareation system is designed with safety measures, like anti-explosion value, inert gas fire extinguishing system, etc.
Project Cases
Pulverized Coal Preparation Station in Shangdong

Coal Powder Vertical Grinding Mill in Ningxia

SPECIFICATIONS

ZKRM Specification and technical parameter of pulverized coal vertical mill
Model	Capacity (t/h)	Geometric diameter of grinding disc (mm)	Grinding disc track diameter(mm)	Feeding size(mm)	Raw coal moisture(%)	Coal fineness(%.R0.08)	Moisture of pulverized coal(%)	main motor power(kW)
ZKRM800M	5-8	1100	800	≤25	<10	5-12%	≤1%	110
ZKRM1100M	7-12	1520	1100	≤25	<10	5-12%	≤1%	132
ZKRM1300M	10-15	1870	1300	≤25	<10	5-12%	≤1%	185
ZKRM1500M	16-22	2180	1500	≤30	<10	5-12%	≤1%	250
ZKRM1700M	20-28	2400	1700	≤30	<10	5-12%	≤1%	315
ZKRM1900M	26-35	2680	1900	≤35	<10	5-12%	≤1%	400
ZKRM2200M	40-45	2900	2200	≤40	<10	5-12%	≤1%	500

Remarks: Raw coal hastelloy coefficient 50-90

PROCESS

Depending on the required coal fineness, there are two types of classifier that may be selected for a vertical roller mill. The dynamic classifier, which consists of a stationary angled inlet vane assembly surrounding a rotating vane assembly or cage, is capable of producing micrometer-fine pulverized coal with a narrow particle size distribution. In addition, adjusting the speed of the rotating cage can easily change the intensity of the centrifugal force field in the classification zone to achieve coal fineness control real-time to make immediate accommodation for a change in fuel or boiler load conditions. For the applications where a micrometer-fine pulverized coal is not necessary, the static classifier, which consists of a cone equipped with adjustable vanes, is an option at a lower cost since it contains no moving parts. With adequate mill grinding capacity, a vertical mill equipped with a static classifier is capable of producing a coal fineness up to 99.5% or higher<50 mesh and 80% or higher <200 mesh, while one equipped with a dynamic classifier produces coal fineness levels of 100% <100 mesh and 95% <200 mesh, or better.