The production process of powdered feed for ruminants such as cattle and sheep is basically the same as the general poultry and livestock feed production process, that is, raw material receiving, crushing, ingredients, mixing and packaging. When producing special pellet feeds for cattle and sheep, corresponding special processes and feed processing equipment are required.
1. Receiving and ingredients of grass meal
When producing compound feed for ruminants, the raw materials include grass meal in addition to general grains, protein feed and minerals. Grass meal is a powdery raw material obtained by pulverizing dry forages. Its bulk density is small and it takes up a large volume. According to the characteristics of the grass meal, the pneumatic conveying system is adopted to receive it, which can increase the output and prevent the grass meal from flying around during the conveying process.
The grass meal batching bin adopts a large outlet and is equipped with a multi-screw screw feeder to send the grass powder to the batching scale in proportion. Multi-screw screw feeders generally consist of 9 to 10 screw feed augers side by side. Due to the formation of a larger feed area, it can effectively prevent grass meal from arching in the silo, and at the same time increase the output of grass meal ingredients.
For sheep/cattle feed plants that do not have a special conveying device for grass meal, in order to prevent grass meal from flying around or arching in the silo during the ordinary raw material conveying device, the hay required for compound feed can be crushed according to the actual situation, and then proportional If it is prepared, it is directly put into the mixer and mixed with the fine material supplements, so as to improve the output and quality of grass meal ingredients. In addition, talcum powder can be added to the grass powder to increase the specific gravity of the grass powder and make it difficult to fly everywhere.
2. Granulation process
Pelleting technology is the most critical and complex central link in the pelleting project of sheep cattle feed plants, which directly affects the quality and output of pellet feed.
Conditioning process
Conditioning is the most important link in the pelleting process of cattle and sheep feed. The quality of conditioning is an important factor affecting the quality of pellet feed. The powdered feed prepared according to the nutritional needs of ruminants such as cattle and sheep enters the conditioner from the silo, and steam is passed into the conditioner to condition the material. In the production of complete feed for cattle and sheep with high fiber content, the amount of steam passed through during conditioning and the temperature of the material after conditioning are slightly lower.
The quenched and tempered material is first removed by the security magnet, and then evenly distributed between the pressing roller and the pressing die, so that the material enters the pressing area from the feeding area through the pressing area, and is clamped into the die hole by the pressing roller to continuously squeeze. Shaped into a columnar feed, as the die rotates, it is cut into pellets by a cutter fixed on the outside of the die. The pellets after cooling by the cooler can enter the pellet crumbler to be crumbled into small pelletss or directly screened as needed. The cattle sheep feed pellets are sieved with a rotary grading sieve, and the pellet feed that meets the specifications is sent to the finished product warehouse and then packed.
Factors affecting pelleting of cattle and sheep feed
Because the pelletization of feed can improve the palatability of feed, increase the digestion and utilization of nutrients, avoid picky eaters, and reduce feed waste, it is very common to feed ruminants such as cows and sheep with complet feed pellets. However, there are certain differences between the animal feed production process for cattle and sheep and the livestock feed production process.
Raw material characteristics
The important factor that affects the pelleting effect of cattle and sheep feed is the raw material characteristics. Different raw materials have different characteristics, which will directly affect the output and quality of pellet feed. Therefore, different forms and different degrees of processing are required in the sheep/cattle feed pelleting process.
Protein and density
Sheep and cattle feed raw materials with higher natural protein have better thermoplasticity and cohesiveness under proper heating conditions, and will produce better quality pellets for cattle and sheep, while raw materials with higher density or feed production will have higher production yields . If the protein content and density of a raw material are both high, it can have higher yield and quality; if the protein content is low and the density is high, it may be the yield is higher but the quality is not good; and when the protein content is high and the density is high when it is very low, it will produce high-quality pellets with a lower output.
Roughage in the feed of ruminant animals such as cattle and sheep generally contains 12%-16% protein, and contains a lot of soft substances and low grain content. This type of sheep cattle feed making raw material has a low ability to absorb moisture, so the amount of steam added should be low to keep the temperature of the powder below 60 ℃ and keep the maximum moisture content between 12% and 13%. If the above standards are exceeded, the pellets out the sheep cattle feed pellet processing machine ring die will be swelled and broken.
Fat
The fat contained in a raw material or feed itself and a small amount of fat added are conducive to the formation of pellet feed. The fat helps to increase the production capacity and play a lubricating effect. But if too much fat is added (up to 2% or higher), the quality of feed pellets will be affected.
Fiber and bulk density
If the fiber content in the feed material is too high, it is difficult to be compressed into pellets, but due to its inherent binding ability, high-quality pellets can be produced with this material, and the fiber content is too high (10%-15 %), it is not easy to squeeze, and it is formed through the die hole. Bulk density is also a factor that determines yield. Generally, low bulk density results in low yield, and high bulk density results in higher yield. For the roughage in ruminant feed, the crude fiber content is high, the bulk density is small, the fluidity of the material in the feed pelleting process is poor, and the pelleting is relatively difficult. Corresponding measures must be taken according to its characteristics to effectively control the pellets' quality after pelleting.
Starch
The raw material or the starch in the raw material can make the starch's natural adhesiveness work under the conditions of high temperature and high humidity, and produce high-quality, firm and durable pellet feed. The higher the starch content in the feed, the easier the pellets are shaped, and the higher the pelleting yield.
Moisture
The moisture of the raw material has a certain effect on the granulation. The water content of the raw material is low, the extrusion resistance is large, the output is low, and the energy consumption is high. Appropriate moisture is beneficial to the formation of dry roughage materials. It is very necessary to add enough water before granulation to obtain good pellet durability.
Crushing particle size
Crushing is another important factor affecting granulation in animal feed production for cattle and sheep feed.The crushing particle size mentioned here is for concentrated feed. The fineness of crushing of concentrate for cattle and sheep can exceed 2 mm. Our recommended "Requirements Before Entering Sheep Cattle Feed Pellet Machine" is 3-5mm. Because cattle and sheep can ruminate, a coarser feed is good for ruminating and improves the digestibility of feed. The feed for old cattle and sheep can be crushed to within 1 mm to facilitate digestion. While considering the types of livestock and poultry, the fineness of crushing must also be considered: the fat-rich grain feed such as corn, oats, etc. cannot be crushed too finely and stored for too long to avoid rancidity and deterioration.
If the ring die specification of the sheep cattle feed pelleting machine does not match the feed type, it will affect the quality and productivity of the pellets produced. Using the same specification animal feed pellet machine ring die to pellet different kinds of raw materials will result in unstable product quality and production efficiency. Therefore, it is necessary to select specific specifications of ring dies according to the characteristics of different feeds to ensure the pelleting quality. Generally, the following factors should be considered when choosing a ring die.
Ring die is generally made of carbon steel, alloy structural steel or stainless steel through forging, machining, drilling die holes and heat treatment. Carbon steel, alloy structural steel or stainless steel can be selected as the material of the ring die for pelleting cattle and sheep roughage. Carbon steel ring die has poor corrosion resistance, alloy structural steel and stainless steel have good corrosion resistance. At present, most of RICHI's sheep cattle feed pellet manufacturing machine ring dies are made of all stainless steel. We have also customized ring dies of other materials for individual customers based on actual feed manufacturing processes.
Under the premise of selecting high-quality ring die, the appropriate die hole form, aperture ratio and compression ratio should be selected according to the raw material variety, moisture and output of the cattle and sheep feed. On the premise of ensuring the strength of the ring die, try to increase the opening rate of the ring die, but it should be noted that the ring die wall is too thin to cause the ring die strength to be insufficient and the bursting phenomenon should be under the premise of ensuring the effective length of the die hole, increase the thickness of the ring die and open more pressure relief holes.
Usually feed producers adjust the specific compression ratio according to the requirements of feed quality. For example, choosing a slightly lower compression ratio is beneficial to increase production, reduce energy consumption, and reduce wear of the sheep cattle feed machine ring die, but it will reduce the quality of the feed, and the pellets are not enough. Strong, loose appearance, different lengths, high powdering rate of feed. A high compression ratio is beneficial to the quality of the pellets. The appearance of the pellets is smooth and shiny, and the pulverization rate is low, but it will increase the production cost of the product. Generally, the compression ratio of the pelletizing ring die for cattle and sheep feed is about 1:6:1:9. The greater the compression ratio of the ring die, the greater the extrusion force of the material, and the material is not easy to pelletize.
Appropriate ring die linear speed is very important to ensure the quality of pellets. If the linear velocity is too high, the particles will leave the ring die with great centrifugal force. When they collide with the inner wall of the pelleting chamber, they will split, increase the powder content, and waste energy. The line speed is too low, the material is easy to block the ring die, and it is difficult to discharge the material.
Roughage has a high fiber content. The fiber can be softened by adding steam or water to improve the pelleting effect. Generally speaking, the tempering temperature and steam pressure of roughage is lower than that of ordinary feed. Therefore, proper control of the addition of steam or water is beneficial to improve the quality of pellets after granulation.
Generally, steam is used to make the material reach an ideal conditioning, that is, the temperature is kept below 60 ℃, and the maximum water content is maintained at 12%-13%. The residence time in the tempering room is more than 30-40s. In short, steam modulation is the most important factor for obtaining high-quality pellets with high productivity and low cost, and the addition of steam can increase the output of almost all feeds compressed by the ring die sheep cattle feed pelletizer, but there are several exceptions, such as mineral feeds and urea. Feeds and other feeds containing large amounts of whole milk powder, whey powder and sugar.
The characteristics of the press roller of the sheep cattle feed pellet production machine also have a certain impact on the pelleting of coarse feed. Due to the characteristics of small bulk density and poor fluidity of coarse feed, straight groove and chute-shaped press rollers are generally selected during pelleting to facilitate the delivery of materials to the extrusion zone. In addition, the pelleting of coarse feed is not only related to the above factors, but also related to the transportation, cleaning, and mixing of materials. To make good cattle and sheep feed pellets, we must pay attention to every detail related to pelleting to ensure the quality and production efficiency of pellets.
