Moisture Content Influence On Grinding Efficiency
No matter in crushing or grinding process, the moisture content of raw materials means a lot and has great influence on the efficiency of machines, especially in dry grinding process. In this article, we mainly talk about the moisture content influence on the efficiency of dry grinding.
In dry grinding process, if the raw materials ground contain too much moisture, the produced powder will adhere to the surface of the grinding media and scale board. And there will form cushion in the grinding cavity, which will reduce the grinding efficiency. When the cushion on the scale board reaches to 20mm, the grinding efficiency will reduce about 70%. Some powder with high moisture content may even block the discharge opening, which will also reduce the grinding efficiency.
According to statistics, when the moisture content of raw materials is above 1.5% in dry grinding process, the capacity of grinding mill will reduce. When the moisture content is above 2.5%, the capacity will reduce about 15%-30%. When the moisture content is very high, the problems in classifier, dust collector will increase, which may even make the whole grinding system halt. The high moisture content of raw materials will also aggravate the corrosion of classifier and the conveying equipment. Also the powders adhered will also increase, which will reduce the transferring capacity.
Seeing the above information, some customers may think that the lower the moisture content, the better. In fact, it is not like that. The ideal moisture content of raw materials to be ground is about 0.5%-1.5%. If the raw materials are too dry, the energy consumption and dust collecting load of drying device will increase. What is even worse, too little moisture evaporation will cause the increasing of temperature in the grinding mill. If the temperature is too high, the grindability of raw materials will decrease, which will also reduce the grinding efficiency.
In fact, proper moisture in raw materials can be considered as activating agent in the dry grinding process. The moisture will evaporate and carburate, and then it can absorb heat and reduce the temperature in grinding mill. Accordingly, it can improve the grinding efficiency and grinding capacity, as well as reduce the energy consumption. So if the moisture content of your raw materials is not proper, customers should take method to deal with this, such as equip a dryer or choosing grinding mills which can dry the raw materials.