Products Center > Mining Equipment > Coal Mill

SBM coal mill is a flexible design, we absorb the advantages of Loesche coal mill and add some features too. Coal mill or coal pulverizer can handle all grades of coal and is highly economical in terms of specific energy consumption. SBM Raymond coal mill can grind all grade coal from hard coal, woody lignite, lignite to anthracite coal, petroleum coke, SBM can supply a turnkey project including design, install, and debug all kinds of coal grinding mill plants.

SBM Raymond coal mill allows clients custom setup in order to suit the required the output, as we have been concerned with pulverized fuel for boilers of power station, we also developed our LM series vertical coal mill. This type coal mill features with compact design, adaptable to specific process requirements, long life time, easy to maintain, so the vertical mill now sets the standard for coal grinding mill.

SBM roller grinding mills are the most efficient grinder mills in the world and achieve very high throughputs. They are also extremely maintenance friendly. Service tasks can be carried out quickly. Downtimes are therefore reduced to a minimum.

In coal fired power plant, coal mill is used to grind, pulverize and dry coal before the coal is transmitted the boiler. The coal is feed into the coal mill via a inlet pipe so that the roller coal mill such as Raymond mill and vertical mill can pulverize the coal into particles.

The hot air in the coal mill will lift the coal particles out of the Raymond mill or vertical mill and into the boiler, if the coal particles are too heavy they will drop to the bottom of the coal mill too and will be grind, pulverize again.

The coal flow into the boiler is an important factor for a coal fired power plant. But in fact, it is not easy to measure the coal flow from the coal mill to the furnace. The coal flow out of the coal mill is often estimated based on the incoming coal flow.

Raw coal is fed through a central coal inlet at the top of the pulverizer and falls by gravity to the rotating grinding table, mixing with classifier rejects returned for re-grinding. Centrifugal action forces the coal outward to the grinding ring where it is pulverized between the ring and three grinding rollers.

Grinding load, transmitted from the tension rods through the loading frame to the roller assemblies, holds the rollers in contact with the grinding ring. The rollers adjust vertically as the depth of the coal load increases or decreases.

　A nozzle ring on the outside perimeter of the grinding ring feeds primary air to the pulverizer. Pyrites and tramp metal fall through the nozzle ring openings to be scraped into a rejects hopper.

　A stream of low-velocity air carries the particles of pulverized coal upward where they enter the classifier inlet vanes. Fine particles travel to the burners in the primary air stream, but the larger, heavier particles are returned to the grinding zone for further pulverization.

SBM coal mill are used in the cement industry for grinding cement raw material, coal, petroleum coke, blast-furnace slag, pozzolana and cement. In order to extend the life of our coal mill, you should do some maintenance .

1, milling machine using the process, there should be regular staff responsible for the custody of the operator must possess a certain level of technology, milling machines are installed before the operation is to conduct technical training for customs officers must make to understand the principle of mill performance, familiar with operational procedures.

　　2, for the mill to work, there should be equipment "Maintenance of the safe operation of systems" can ensure the long-term safe operation of mills at the same time have the necessary repair tools and accessories grease.

　　3, mill use for some time, maintenance should be carried out, while roller grinding ring Blade repair of wearing parts such as replacement roller device in use before and after the connecting bolt nut plug should be carefully examined whether there is loosening , lubricating oil is to add a little grease.

　　4, roller devices of the time more than 500 hours or so to replace the roller when the roller kit must be cleaned of all rolling bearings, damaged parts should be replaced, dispensing fuel or butter can be used to manually hand gun.

Improper operation of the coal mill may cause the explosion of the machine . What is the proper method to operate coal mill to avoid the disaster?

1. change the piling method of the coal to make the coal accumulate little ; thus avoid the spontaneous combustion 　　　of the coal .
　　2. change the gap of the grate bar from 25mm to 22mm; thus decrease the wind speed and increase the drying speed .
　　3. add a settling chamber between the coal mill and the pipe; thus prevent the hot coal powder enter the coal mill .
　　4. add a explosion-proof valve at the opening .
　　5. increase the fineness of the coal from 10% to 15% .
　　6. make up strict safety rules .

　　If the coal mill stops for 3 days, empty the coal hopper or put a layer of raw meat powder on the surface to isolate the coal from the oxygen before stopping the coal mill, close the hot wind valve and open the close wind valve and then stop the feeding. remember to empty the coal in the coal mill before stopping the machine and not to stop the collector immediately .
　　Check the following things when operating the coal mill: the airing is ok; there is no overfeeding or underfeeding; the temperature is not too high; the order of starting and stopping the coal mill is right; the temperature of the air from the coal mill is higher the dew point.
　　Make an emergency plan; when an explosion happens, close the hot wind valve and the pneumatic valve, prevent the hot coal powder enter the collector and if the temperature is over 80 degree centigrade, start the carbon dioxide extinguisher.
we should pay attention to avoid safety problem in operating the coal mill. as long as we obey the safety rules, the safety problems surely can be avoided.

SBM ygm coal mill is a new kind of mill, which is invented by our company chief engineer Mr Bai yinghui, who has been engaged in the research and development of grinding machine for many years. SBM coal mill is the main equipment of coal powder production system of thermoelectric power station, and it is also the essential equipment for drying and pulverizing coal power in cement plant. SBM coal mill can grind coal perfect. This new patent product with high efficiency and low energy consumption opened up an epoch of the international industry pulverizing.

The ygm coal mill now sets the standard for coal grinding installations. The coal mill can handle all types of coal and is highly economical in terms of specific energy consumption. And the features and benefits introduce of our coal mill below :

1. Compact design, Simple structure, easy maintenance.
2. Grinds any type of coal and High crushing ratio.
3. Adaptable to specific process requirements .
4. High drying ability, reliable operation.
5. Long service life of grinding parts .
6. Reliable performance, low operation cost .
7. Easy maintenance.
8. Stable quality, convenient maintenance.
9. Low invest, high return .

SBM ygm coal mill is mainly applied to the powder processing of mineral products in industries. Raw coal is fed through a central coal inlet at the top of the pulverizer and falls by gravity to the rotating grinding table, mixing with classifier rejects returned for re-grinding. Centrifugal action forces the coal outward to the grinding ring where it is pulverized between the ring and three grinding rollers.

　　Grinding load, transmitted from the tension rods through the loading frame to the roller assemblies, holds the rollers in contact with the grinding ring. The rollers adjust vertically as the depth of the coal load increases or decreases.A nozzle ring on the outside perimeter of the grinding ring feeds primary air to the pulverizer. Pyrites and tramp metal fall through the nozzle ring openings to be scraped into a rejects hopper.A stream of low-velocity air carries the particles of pulverized coal upward where they enter the classifier inlet vanes. Fine particles travel to the burners in the primary air stream, but the larger, heavier particles are returned to the grinding zone for further pulverization.