Taking the 1000 t / D all sliming cyanidation carbon slurry plant project of Indonesia gold mine completed by Zenith 2018 as an example, we will elaborate the main contents of Raymond Mill commissioning of the project and the overall process of Raymond Mill commissioning from the three stages of Raymond Mill commissioning.

1、 Preparation stage before Raymond Mill commissioning preparation means that before starting Raymond mill, it is necessary to check whether all components meet the requirements of commissioning.

The main contents to be checked include lubrication, cooling, heating, sealing and fastening of various components.

Raymond Mill commissioning can be started only after the person in charge of each department ensures that all parts meet the conditions of commissioning.

Zenith wet overflow Raymond mill is selected for SBM Indonesia 1000t / D gold mine all sliming cyanidation project.

The grinding concentration determines the friction between grinding medium and material, pulp fluidity, effective density and effective weight of medium, and then affects the production efficiency of vertical roller mill. 

The grinding concentration also has a suitable range, which is too large or too small. In actual production, we generally advocate "high concentration grinding and low concentration classification". 

Generally, the grinding concentration is comprehensively determined by material properties, grinding process conditions, classification efficiency and overflow concentration. 

Taking the lattice vertical roller mill as an example, when coarse grinding (› 0.15mm), the grinding concentration should be controlled between 75 ~ 85%; When the overflow vertical roller mill is used to treat fine grinding products (0.10 ~ 0.074mm), the grinding concentration is generally controlled between 65 ~ 75%. 

 

In this case, Raymond mill is likely to cause "belly swelling", that is, the negative pressure in the cylinder is too large and the grinding effect is lost; However, if the ore feeding amount is insufficient, the ore discharge particle size of Raymond mill will become smaller and the sand return amount will be reduced accordingly.

In serious cases, the lining plate and grinding medium will make an obvious impact sound, resulting in the endless loss of grinding medium and lining plate.

When the ore feeding amount remains unchanged, the increase or decrease of ore feeding particle size will also be similar to the above situation. Therefore, the ore feeding quantity and particle size should be continuous, uniform and stable at a high level.

 

When entering the mill is too large, the grinding body and the lining plate will adhere, resulting in paste grinding, blocking the grate plate and full grinding. 

However, containing a small amount of moisture can effectively reduce the temperature and static electricity of vertical roller mill operation. Therefore, the average moisture of vertical roller mill operation is generally controlled at & lt; 15% is appropriate. 

Allowable moisture content of grinding material (for reference only) allowable moisture content of grinding material name rotary kiln and shaft kiln clinker 0.5 granular blast furnace slag 2.0 natural pozzolanic ash 2.0 limestone 1.5 clay 1.0 gypsum 10.06, vertical roller mill operation steel ball grading is unreasonable, which is to realize the impact and grinding of materials with different particle sizes, so as to improve the grinding efficiency, Therefore, the grading of vertical roller mill operation steel ball is very important.

 

Therefore, ensuring that the output of silica sand mill meets the standard is the top priority it is a very common problem that the output of silica sand mill fails to meet the design requirements in the production of concentrator. 

Under what circumstances will the output of silica sand mill fail to meet the design requirements? 1. 

The unreasonable design of the length proportion of each silo of silica sand mill will cause the imbalance of the coarse and fine grinding capacity of silica sand mill, resulting in the phenomenon of too coarse or too fine fineness of products, and then affect the output. 

Under normal circumstances, the length ratio of each warehouse of silica sand mill is as follows: warehouse number, warehouse type, 1 warehouse, 2 warehouse, 3 warehouse, single compartment 30 ~ 4060 ~ 70, double compartment 25 ~ 3025 ~ 3045 ~ 50.

 

Generally, the grading range is 25% ~ 35%, but the intermediate grading in practical application is mostly 28% ~ 32%. LM vertical roller mill steel ball grade ratio under common economic operation: steel ball diameter mm Φ one hundred Φ eighty Φ sixty Φ forty Φ 20 mass / total filling quantity 7.5% 6.9% 33.5% 30.1% 22 note: when the grindability of materials is poor or the grinding requirements are fine, the filling rate of one bin shall be & gt; 28%。

The temperature of LM vertical roller mill grinding material is too high. Generally, when the temperature of LM vertical roller mill grinding material is too high, it is easy to reduce the grinding efficiency. When the temperature of LM vertical roller mill exceeds 100 ℃, an air film isolated from each other on the surface of small particles of the material will be damaged, resulting in adhesion.

In order to reduce the temperature in the mill and improve the milling efficiency, a small amount of mist water can be sprayed into the milling bin to reduce the temperature in the mill to below 50 ℃.

Under what circumstances will the output of LM vertical roller mill fail to meet the design requirements? 

Unreasonable design of length proportion of each bin of LM vertical roller mill unreasonable length proportion of each bin of LM vertical roller mill will cause imbalance of coarse and fine grinding capacity of LM vertical roller mill, resulting in excessive coarse or fine fineness of products, and then affect the output. 

Generally, the length ratio of each warehouse of LM vertical roller mill is as follows: warehouse number, warehouse type, 1 warehouse, 2 warehouse, 3 warehouse, single compartment 30 ~ 4060 ~ 70, double compartment 25 ~ 3025 ~ 3045 ~ 50. Note: the data are for reference only, and the specific equipment warehouse length ratio shall be subject to the design of the manufacturer. 

 

The development of ultrafine mill now or in the next few years is for the better development and future of ultrafine mill enterprises. Ultrafine mill is one of the most difficult barriers to the development of ultrafine mill industry in the future.

China is a developing country. After the reform and opening up, all walks of life in China have entered a period of rapid development. The ultrafine mill industry in China started late, but developed rapidly. Before the 1990s, it belonged to the processing and crushing of low and medium hardness materials. 

After years of development, ultrafine mill also has various changes. Ultra fine mill is the mainstream production equipment in the future ultrafine mill industry. The future changes are also summarized, mainly divided into several aspects: environmental protection, large-scale machinery, meeting market demand, technological innovation and so on.

 

Compared with the traditional grinding equipment, grinding machine can effectively improve and eliminate the wear of the equipment caused by the heat generated by production, and can meet the shortcomings of the traditional grinding equipment.

The crushing method adopted by the new vertical roller mill is shear type. During operation, the materials will be sent to the position where the grinding ring is installed between the static disc and the moving disc. 

Once the moving disc of mill rotates, the grinding ring will gradually cut the materials. According to the different needs of production, the installation accuracy and speed of the motorized stationary plate of vertical roller mill can be adjusted reasonably, which will minimize the damage to equipment and the waste of materials in the production process.

For example, the prices of ultra-fine mill and jaw crusher are different; The price of 300 mesh small ultra-fine mill is different from that of 200 mesh small crusher. The price of mills with more than 300 mesh is another level. We often budget the price according to the overall configuration of the mill.

In an ore production line, many kinds of equipment are needed, including crusher, ultrafine mill, screening equipment and other auxiliary equipment. Crushers are divided into many types, such as jaw crusher, impact crusher, roller crusher, cone crusher and so on. 

Grinding machine is divided into ultra-fine grinding, T-shaped grinding and so on. According to the required material fineness, customers need to choose different mills. The price difference is also shown here. Correctly budgeting the cost of an ore production line can help customers better grasp their investment and income.