Feed production is a combination of a series of processing equipment and conveying equipment. Reasonable design process and selection of equipment are also important links in safe feed production. It is mainly to reduce the gradation and residue of material in the processing process, and at the same time, to use the heat treatment in the process to eliminate the influence of anti-nutritional factors and harmful microorganisms in the raw materials.
1. Classification of the processing process In feed processing, the difference in the density of the feed components, the difference in the carrier particle size, and the miscellaneous components such as the additive and other minor components in the feed are not sufficiently mixed, which results in a graded important reason. Feeding, loading, and unloading of raw materials can also result in grading. Manual operations and improper design of processing processes can also lead to grading. Measures to reduce classification are to rationally design the feed processing process and select high-quality and precise equipment; to ensure uniform mixing of raw materials by adjusting the composition of raw materials and the particle size of crushed; to carry out effective load carrying on micro-components to change the mixing of trace components. Characteristics; adding liquid components to increase the adhesion of the powder; granulating or expanding the product also helps to avoid the above phenomenon. For powdered products (especially composite premixes), the finished powdered material after mixing should be kept to a minimum distance to reduce the effect of material grading.
2. Residual pollution during processing Many factors can cause feed residue in the equipment leading to cross-contamination. If corresponding measures are taken in process design and equipment selection, the generation of residue can be reduced. In the process design, the transfer process uses the form of distributors and self-flow as much as possible and uses less horizontal transport. For horizontal conveying equipment, such as screw conveyors and scraper conveyors, due to structural reasons, there are more or less residual materials, which should be easily accessible and easy to clean during equipment design, or use scraper conveyors with self-cleaning function. Under the conditions of meeting the process requirements, the number of material lifts and the number of buffer bins should be minimized. The suction and dust removal system sets up an independent wind network as far as possible, and the collected dust is directly sent back to the original place to prevent secondary pollution, especially for the production of the compound premix of dosing. The measurement of trace components should be arranged as far as possible in the upper part of the mixer. If it is necessary to lift or transport after metering and weighing, high-density pneumatic transport must be used to prevent gradation and residue. High-risk trace components such as drugs must be added directly to the mixer. Medicinal feed production should use special production lines as far as possible to minimize the risk of cross-contamination. In order to reduce the residual impact on the feed, some cleaning devices can be designed to use compressed air to clean certain parts of the equipment. In the selection of equipment, the accuracy of the electronic equipment and mixing equipment of the metering equipment should be determined. The metering equipment and electronic scales should be determined according to the nature of the materials of different proportions in the selection of the measuring range. The metering equipment with the same amount of wood is used to meet the requirements of different materials. The request. In the production of compound feed and composite premix, the choice of mixer is important. The mixer should be able to achieve a mixing accuracy of no more than 5% with a coefficient of variation of one in 100,000. The design of the mixer should ensure that as little material as possible remains in the mixer after each batch is mixed. Due to the difference in particle size and the final product requirements for production, in the production of premixed feeds, the particle size of the materials is small, the mixing uniformity is high, the required residues are small, and the materials are electrostatically generated during the mixing process. The characteristics of the blended material require different mixers. Bucket elevators, chutes, batching and buffering hoppers will also generate residue. When selecting equipment, the internal surfaces of the chute, silo, and hopper should be required to be smooth, leaving no dead ends. Irrational liquid additions can also have an impact on the residue of the material and should be noted.
3. Application of heat treatment process The effect of heat treatment before and after conventional granulation depends on temperature, time, and quality of steam. The role of quenching and tempering is to improve the quality of pellet feed and improve the digestibility of feed. At the same time, it can destroy the anti-nutritional factors in the raw materials, kill harmful microorganisms in the raw materials, and control the sanitary quality of the pellet feed. This quenching and tempering process is limited by the structure of the pellet machine and the effect of tempering is not ideal. At present, improvement has been made in the refining and tempering process, mainly by increasing the time of quenching and tempering to prolong the time of conditioning and improving the hygienic quality of the feed after conditioning. Another method is to use expansion or extrusion method, make full use of time, temperature, combined with mechanical shear and pressure, high treatment intensity, sterilization effect is more obvious. Expansion or extrusion conditioning improves the quality of the feed.
4. Problems with external spray applications Heat-sensitive substances can cause losses during the heat treatment process, so they can be added during the conditioning process without adding them. These substances are added to the surface of the particles and may cause particles to be powdered in the process of transportation or transportation. After the surface coating materials are pulverized, they are enriched and evenly distributed. Therefore, the outer coating should be used to make the outer coating material tightly bound to the granules. The granule processing quality is a guarantee of the quality of the outer coating. Usually, the coating effect of the extrusion coating product is better.