In order to make quality feed pellets and improve operation efficiency of feed mill equipment, this article describes the components, the basic operations and the proper maintenance of feed mill equipment.
There are various pellet machinery types, like feed pellet machinery, wood pellet machinery, fertilizer pellet machinery, and so on. Here we are going to talk about the pellet machinery for making animal feed pellets and extruded aquatic feed pellets.
Extruder is the prominent machine applied in aquafeed production, where the feed is subject to mixing, shearing and heating under high pressure before the extrudate finally is forced through a die. The general extrusion process involves a high tempera
Pig feed pellet size has two dimensions: the feed pellet diameter and the feed particle size (the grinding fineness of ingredients). And the particle size is a leading factor affecting feed quality, thus pig performance.
Fish feed is to feed fishes including prawns and shrimps to provide the energy and essential nutrients with them, and the requirements of fish feed are different in quantity and quality according to their different sizes, reproductive states, feeding
Beet pulp pellets create a new way for feeding horse and cattle with less expensive price and more nutritional even than alfalfa pellets. We supply beet pulp pelletizing solution for beet sugar factory.
Grass feed pellet quality is determined by factors such as material water content, ingredients formula, feed pellet mill design, conditioning effect etc, you can find detailed guidance in this article.
Feed processing technology has great influence on the hardness of pellet feed including grinding, expansion, mixing, water adding and fuel injection process, steam conditioning, ring die pelletizing, post curing & post spraying and drying & cooling.
Feed pellet extruder can produce premium fish feed pellet which greatly help fish grow healthily and it can be divided into two types: dry type fish feed extruder and wet type extruder.
Pig feed pellets is processed under the action of 100 ~ 120℃ hot steam. It is easier for pigs to digestion and absorption. Pig feed pellets making process including raw materials crushing and mixing, conditioning and pelletizing, cooling and packing
I. Ingredients Grinding
The pulverization fineness of feed ingredients plays the decisive role in feed pellets hardness. Generally speaking, the finer the particle size the better the starch gelatinization, which can ensure stronger bonding of feed ingredients. Thus feed pellets have good hardness and are not easy to be broken. In actual production, the pulverization fineness should be adjusted depend on animal production performance and diameters of ring die holes. For poultry feed pellets, the particle size of raw materials should be bigger with average diameter of 800-900μm; for baby pig pellets, the particle size is around 400-500μm; for finishing pig pellets, the particle size is reduced to 600-700μm; for fish and aquatic feed pellets, the particle size is below 250μm.
For poultry feeding, the pellets should be with greater hardness and lower pulverization rate to reduce feed wastage. To improve the hardness of poultry feed pellets, you can regulate the proportion of coarse, medium and fine particle size in the mixing of grinded ingredients as follows: coarse particle size with the diameter of above 900μm are less than 15%; medium particle size of 700μm are round 35%; fine particle size of below 500μm are more than 50% including no less than 25% fine powder of below 250μm. The starch in the fine powder can be fully gelatinized in the conditioning process, which can enhance the bonding of particle sizes in pellets. So these coarse, medium and fine particle sizes are bonded together to form big pellets to improve the pellet hardness and reduce product pulverization rate.
For pig feeding, the hardness of pellets should be moderate. Too hard, the product palatability and production performance get lower; too soft, pulverization rate gets higher and production performance gets lower, which results in increased wastage. In the proportion of grinded materials, the particle sizes of 700-500μm should be over 70%, and particle size of below 250μm should be over 20%. Thus, this distribution of particle sizes contributes to forming pellets, improving pellet performance quality and keeping the right pellet hardness and lower differentiation rate.
For fish feeding, the proportion of crushed materials depends on fish physiological characteristics. Particle sizes of 250μm should be not less than 85%. Moreover small particle sizes are beneficial to pellet forming and stability in the water. Fish feed pellets are always in high hardness because of the demand for high stability of fish feed in water.
III. Feed Ingredients Mixing, Water Adding & Fuel Injection
Raw materials mixing can strengthen uniform distribution of various feed particle sizes to ensure formed feed pellets in basically identical hardness. Water adding technology in the mixer is still being actively sought. In hard feed pellet production, adding 1%-2% water in the mixer is beneficial to improving the stability & hardness of pellet feeds. But the increased water brings negative effect on drying & cooling feed pellets and also is bad for pellet storage. In the wet pellet feed production, you can add 20%-30% water in powder and 10% water in the mixing, which is easier than adding water in conditioning. Feed pellets made of high-moisture materials are featured with low hardness, wet & soft, good palatability, which can improve livestock and poultry production performance. In the large-scale farming enterprises, the wet pellet feed can be adopted. Because it can not be stored which means wet pellets should be immediately used after production. Adding fats in the mixing is generally adopted to meet the nutrition needs of animals. Adding 1%-2% fats does not significantly reduce the pellet hardness but adding 3%-4% fats will significantly reduce the granule hardness. So the amount of adding fats should be controlled.
Steam conditioning is the key part in feed pellet production. Conditioning effect directly affects granule internal structure and appearance quality. Steam quality and conditioning period are two vital factors that affect conditioning effect. Highly dry and saturated steam can provide more heat to increase the temperature of materials, which makes starch gelatinized. The longer the conditioning time the higher gelatinization degree of starch. Therefore formed granules are with compact structure, high stability and strong hardness. For animals and poultry feeding, you can adjust steam addition to keep conditioning temperature from 70 to 80℃. Through adjusting length of conditioner, paddle angle and rotating speed, you can keep conditioning period for around 30 seconds. For fish feed, double layer or multilayer jacketed conditioner is always employed to improve temperature and prolong conditioning period, which contributes to better strengthening fish feed pellet stability in the water and hardness.
V. Ring die
The aperture and compression ratios of ring die can prominently affect granule hardness. Adopting ring dies with the same aperture but different compression ratios, increase of pellet hardness will accompany with the the increase of compression ratios. With the suitable compression ratios, you can produce pellets with right hardness.
VII. Pellet Drying and Cooling
In feed pellet making process, factors that affect pellet hardness are more that the above. Believe that more and more methods of regulating granule hardness can be mastered by people. In the future we can produce kinds of pellet feed favored by animals!