The dust and noise in feed processing mainly come from the crusher. The two environmental sanitation indexes should be fully considered in selection. If the pulverizer with high noise and dust has to be selected, the noise reduction and dust prevention measures shall be taken to improve the working environment and the health of the operators.
1. First of all, we should consider what kind of raw materials are crushed by the purchased feed crusher. The hammer crusher with top feeding can be selected for crushing grain feed; the claw crusher can be selected for crushing bran, grain and wheat feed; the hammer crusher with tangential feeding can be selected if it is required to have good universality, such as mainly crushing grain, taking into account both cake, grain and straw; the shell non screen crusher can be selected for crushing mineral feed such as shell; if it is used for premixing For the pre-treatment of compound feed, if the particle size of the product is required to be very fine and can be adjusted according to the needs, the special non screen crusher shall be selected.
2. Generally, the specification and nameplate of the crusher contain the rated production capacity of the crusher (kg / h). However, we should pay attention to the following points: (1) the rated production capacity is generally based on the status of crushed corn, with water content as the safe water storage (about 13%) and φ 1.2mm sieve plate. As corn is commonly used grain feed, the sieve plate with diameter of 1.2mm is the commonly used minimum sieve hole. At this time, the production capacity is small, which takes into account the more common and more difficult state in production 。 (2) The production capacity of the selected crusher is slightly larger than the actual production capacity, so as to avoid the continuous production and supply of feed being affected when the production capacity of the crusher is reduced due to the wear of hammer pieces, air leakage of air duct, etc.
3. The energy consumption of feed crusher is very large. When purchasing, energy saving should not be ignored. According to the standards of relevant departments, the output of each kilowatt hour of hammer crusher shall not be less than 48kg when crushing the sieve with φ 1.2mm mesh for corn. At present, the kilowatt hour output of domestic hammer feed crusher has greatly exceeded the above requirements, and the high-quality one has reached 70-75kg / kilowatt hour.
4. Matching power of feed crusher. The instructions and nameplate of the machine contain the power kilowatts of the motor matched with the crusher. It often indicates not a fixed number but a certain range. There are two reasons for this. One is that there is a big difference in the power required for different varieties of raw materials. For example, under the same working conditions, the power required for crushing sorghum is twice as high as that required for crushing corn. Second, when using different mesh, the load of the crusher has a great impact.
5. The discharge mode of feed crusher shall be considered. There are three ways to output crushed products through discharging device: self weight blanking, negative pressure suction conveying and mechanical conveying. In order to simplify the structure, the self weight cutting method is often used for small single machine. Most of the medium-sized pulverizers are equipped with negative pressure suction device, which has the advantages of absorbing the moisture of the finished products, reducing the humidity in the finished products is conducive to storage, improving the pulverizing efficiency by 10-15%, and reducing the dust level in the pulverizing chamber. The mechanism conveyor is mostly used for the crusher with a table output of more than 2.5t.
6. Dust and noise from the crusher. Due to the influence of voltage, operation method, environment and other factors, the output has changed. Therefore, it is an important problem for feed production to properly master feed crusher technology and select appropriate feed crusher.
