Ball milling, rod grinding process For the ore selection process, one or two stages of grinding can be used to economically grind the material to any particle size required for beneficiation . The grinding of more than two stages is usually determined by the requirements of the stage selection. Compared with the two processes, the advantages of a grinding process are: less equipment, low investment, simple operation, no impact on another grinding section due to one node shutdown, and less downtime. The disadvantage is that the mill has a wide range of feed size, reasonable ball loading, and it is not easy to obtain the final product, and the grinding benefit is low. If the required particle size is 0.2~0.15mm (ie 60%~90%-200 mesh), a grinding process is generally used. For small plants, the process flow and equipment configuration are simplified, and when the discharge size is not high, a one-stage grinding process can be used. The advantage of the two-stage grinding process is the ability to obtain a finer product that can be coarsely ground and finely ground in different grinding sections, especially for staged processing. In medium-sized and above factories, when grinding grain size is less than 0.15mm (ie 80%-200 mesh), it is economical to use staged grinding, and the product has uniform particle size composition and less over-grinding. According to the different connection modes of the mill and the classifier, the two-stage grinding process can be divided into three types of connection: the first section of the open circuit, the second section of the closed circuit, the first section of the partial closed circuit, and the second section of the closed circuit. Grinding process. Self-grinding process The self-grinding process has two types: dry grinding and wet grinding. The concentrator often uses wet grinding to process the material. Adding a small amount of steel balls to the self-Grinding Machine can effectively solve the problem of difficult-to-grind materials in self-grinding, which is called semi-self-grinding. Self-grinding often works in conjunction with various grinding equipment , and can be composed of a variety of processes depending on the connection method. Vacuum freeze drying technology is currently the most advanced food drying dehydration processing technology, compared with other drying or air drying method. Vacuum freeze drying produce of freeze-dried food, can not only keep the very good material color, appearance, taste and nutrition, etc., and can save for a long time, after water is wonderful, and convenient transportation. After drying of food volume, shape, material is spongy and swear shrinkage phenomenon, can be widely used in vegetables, fruits, spices, aquatic products, biological products, medicine, Chinese herbal medicine, beverage, chemical industry, etc. Freeze drying machine,Vacuum freeze drying machine Changzhou Ruide Drying Engineering Technology Co., Ltd , http://www.rddryer.com