(1) Flow chart of the production process of compound feed (omitted)
 
(2) Receipt of raw materials
 
1. Receipt of bulk raw materials If it is transported by bulk trucks or trains, the raw materials are unloaded to the unloading pit after being weighed by a dump truck.
 
2. Receiving of packaging raw materials: It is divided into two types: manual handling and mechanical receiving.
 
3. Receipt of liquid raw materials: bottled and poke-packed can be directly transported into storage by hand.
 
(3) Storage of raw materials
 
There are many states of raw materials and materials in the feed, and various forms of silos must be used.
 
The main raw materials such as corn, high grain and other grain raw materials have good fluidity and are not easy to agglomerate, and are mostly stored in silos, while the auxiliary materials such as bran, soybean meal and other powdery raw materials have poor scattering properties and are easy to agglomerate after being stored for a period of time. The material is discharged and stored in a room-type warehouse.
 
(4) Cleaning of raw materials
 
Impurities in feed raw materials not only affect the quality of feed products, but are also directly related to feed processing equipment and personal safety. In severe cases, the entire equipment may be damaged, affecting the smooth progress of feed production, so they should be removed in time.
 
The cleaning equipment of the feed factory is mainly based on screening and magnetic separation equipment. The screening equipment removes large and long debris such as stones, mud blocks, and sacks in the raw materials. The magnetic separation equipment mainly removes iron impurities.
 
(5) Crushing of raw materials
 
The technological process of feed crushing is determined according to the required particle size, the variety of feed and other conditions.
 
According to the number of crushing of raw materials, it can be divided into primary crushing process, cyclic crushing process or secondary crushing process.
 
According to the combination with the batching process, it can be divided into the first batching and then crushing process and the first crushing and then batching process.
 
1. One-time crushing process:
 
It is the simplest, most commonly used and most primitive crushing process. Whether it is a single raw material or a mixed raw material, it can be crushed at one time. According to the number of crushers used, it can be divided into single-machine crushing and parallel crushing. Small feed processing plants Most of them use single-machine pulverization, and medium-sized feed processing plants use two or more pulverizers in parallel. The disadvantage is that the particle size is uneven and the power consumption is high.
 
2. Secondary crushing process
 
There are three process forms, namely single cycle crushing process, stage crushing process and tissue crushing process.
 
(1) Single cycle secondary crushing process
 
A pulverizer is used to pulverize the material and then sieve, and the material on the sieve is returned to the original pulverizer to be pulverized again.
 
(2) Stage secondary crushing process
 
The basic setting of this process is to use two pulverizers with different sieves, each with a grading screen, the material is first sieved through the first sieve, and the material under the sieve that meets the particle size requirements is directly sent to the mixer. The material enters the first pulverizer, and the pulverized material enters the grading screen for screening. The materials that meet the particle size requirements enter the mixer, and the rest on the screen enter the second pulverizer for pulverization, and then enter the mixer after pulverization.
 
(3) Combined secondary crushing process
 
In this process, different types of pulverizers are used in two pulverizations. The first time adopts a pair of roller pulverizers. After being screened by a grading screen, the under-sieve material enters the mixer, and the over-sieve material enters the hammer mill for the first step. Secondary crushing.
 
3. First batching and then crushing process
 
According to the design of the feed formula, the ingredients are first mixed and mixed, and then enter the pulverizer for pulverization.
 
4. First crushing and then batching process
 
In this process, the powder to be pulverized first, enters the batching bin respectively, and then batches and mixes.
 
(6), batching process
 
At present, the commonly used technological processes include manual addition of ingredients, volumetric ingredients, one warehouse and one scale, multiple warehouses and several scales, and multiple warehouses and one scale.
 
1. Manually adding ingredients
 
The manual control of adding ingredients is used in small feed processing plants and feed processing workshops. This batching process is to manually weigh the various components of the ingredients, and then manually pour the weighed materials into the mixer. Because all manual metering and batching are used, the process is extremely simple, the equipment investment is low, the product cost is reduced, the measurement is flexible and accurate, but the manual operating environment is poor, the labor intensity is high, and the labor productivity is very low. After time, error prone.
 
2. Volumetric ingredients
 
Each batching bin is equipped with a volumetric batching device
 
3. One warehouse and one scale ingredients
 
4. Batching with multiple warehouses and one scale
 
5. Batching with multi-storage scales
 
Group the measured materials according to their physical characteristics or weighing range, and each group is equipped with a corresponding measuring device
 
(7) Mixing process
 
Can be divided into batch mixing and continuous mixing
 
Batch mixing is to mix various mixing components according to the proportion of the formula, and send them to the "batch mixer" that works periodically for mixing in batches. This mixing method is more convenient to change the formula. There is less mixing between them, and it is a commonly used mixing process. The opening and closing operations are more frequent, so automatic program control is mostly used.
 
The continuous mixing process is to continuously measure various feed components at the same time, and mix them into a stream containing various components in proportion. When this stream enters the continuous mixer, it is continuously mixed to form a uniform stream. Material flow, the advantage of this process is that it can be carried out continuously, and it is easy to connect with continuous operations such as pulverization and granulation. It does not require frequent operations during production, but when changing formulas, the flow adjustment is more troublesome and continuous. There is a lot of material residue in the conveying and continuous mixing equipment, so the problem of mutual mixing between the two batches of feed is more serious.
 
(8) The granulation process
 
1. Conditioning and tempering: Conditioning and tempering is the most important link in the granulation process. The quality of conditioning directly determines the quality of pellet feed. The purpose of conditioning is to temper the prepared dry powder into a powdered feed with a certain moisture and humidity that is conducive to granulation. At present, feed factories in my country complete the conditioning process by adding steam.
 
2. Granulation:
 
(1) Ring die pelleting:
 
The uniformly quenched and tempered materials are first removed by the security magnet, and then evenly distributed between the pressing and mixing and the pressing die, so that the material enters the pressing area from the pressing area of ​​the feeding area, and is continuously squeezed by the pressing roller into the die hole. It is divided into columnar feed, and as the die rotates, it is cut into pellet feed by the cutter fixed outside the die. And you can go to see the ring die chicken feed pellet machine.

 
(2) Flat-die granulation
 
The mixed material enters the granulation system, and the rotary distributor located at the upper part of the granulation system evenly spreads the material on the surface of the die, and then the material is pressed into the die hole by the rotary press-mixer and pressed out from the bottom, through the die hole. The outgoing rod feed is cut into the required length by the cutting roller.
 
3. Cooling
 
During the pelletizing process, due to the introduction of high-temperature and high-humidity steam and the extrusion of the material, a large amount of heat is generated, so that when the pelleted feed comes out of the pelletizer, the moisture content reaches 16%-18%, and the temperature is as high as 75 ℃-85 ℃, under this condition, the pellet feed is easily deformed and broken, and the phenomenon of sticking and mildew will also occur during storage. The moisture must be reduced to below 14%, and the temperature must be reduced to below 8 ℃ higher than the air temperature, which requires cooling.  Select the feed cooling machine in LIMA Machinery.

 
4. Broken
 
In the production process of the pellet mill, in order to save electricity, increase output and improve quality, the material is often made into pellets of a certain size, and then crushed into qualified products by a crusher according to the particle size of livestock and poultry feeding.
 
5. Screening:
 
After the pellet feed is processed by the crushing process, a part of powder coagulation and other materials that do not meet the requirements will be produced. Therefore, the crushed pellet feed needs to be screened into products with neat particles and uniform size.