Why animal feed pellet machine is so important to pellet quality? There are many factors that affect the quality of pellets, the most important ones are formula, powder size, conditioning, roller and die properties and cooling. Among them, the influence of conditioning on the quality of pellets accounts for about 20%, and the influence of the working characteristics of the press die on the quality of pellets accounts for about 15%. These two elements are directly determined by the animal feed pellet mill. Even if the formula has the greatest impact on pellet quality, accounting for about 40%, as a feed processing equipment, the feed pelletizer is undoubtedly the most critical. Then, how does the animal feed pellet machine affect the pellets quality? We will explain in detail below:
1. Conditioning of animal feed pellets
Conditioning is a process in which the powder is fully contacted and stirred with a small amount of steam in the conditioner of the granulator. The role of conditioning is:
- Increase moisture (can lubricate the die hole and reduce friction);
- Increase the temperature of the material;
- Soften the material to facilitate granulation.
The conditioning treatment is conducive to the gelatinization of starch, the digestion and absorption rate of feed, the improvement of pellet quality, the increase of output, the reduction of energy consumption, the reduction of the wear of the die and the roller, and the improvement of their service life.
The influence of the working characteristics of the die on the quality of the pellets accounts for about 15%. Among them, the length to diameter ratio of the die hole is the main factor, and other factors such as the linear speed of the die, the gap between the die rolls, and the size of the output also have a certain influence. When the length to diameter ratio is large, the material stays in the die hole for a long time, and the pressure is also large, so the hardness of the pellets is low.
Different types of pellet feed have different requirements for the length to diameter ratio. For example, the length to diameter ratio of livestock and poultry feed is generally 8-10, aquatic feed is 14-16, and shrimp feed is 20 or more. The linear speed of the die has been determined during the design of the animal feed pellet granulator and generally cannot be changed at will.
The gap between the pressure die and the pressure roller should be adjusted properly, generally between 0.1-0.2mm. If the gap is too small, there will be friction between the pressure die and the pressure roller, which will accelerate the wear of the pressure die and the pressure roller. However, if the gap is too large, the output will be reduced, and even the particles will not be able to be pressed. The output size will affect the residence time of the material in the die hole, and the pellet quality will be better when the output is low. So sometimes in order to ensure quality, don't pursue output too much.
Other factors affecting feed pellets quality:
3. Formulation
The animal feed formula has the greatest impact on the pellet quality, accounting for about 40%. This is due to the comprehensive physical properties of various feed making raw materials. Some raw materials are easy to make granules, but some are difficult to make granules (mineral salt, sand, etc.). Therefore, everyone must have a clear understanding of the influence of the formula on the quality of the pellets.
Here is a practical example. The pellet quality of a certain feed factory's pellet feed has been poor. The formula technicians believe that their formula nutrition is appropriate, and the poor pellet quality has nothing to do with them. The technicians in the workshop took some measures, and the quality of the pellets was not ideal. After explaining the truth to them, the formulation technicians made corresponding changes to the formula, and the quality of the pellets was immediately improved.
4. Powder particle size
The influence of powder particle size on particle quality is about 20%. If the particle size is too coarse, the quality of the particles will not be good.
The inclusion of particles in the powder will also affect the quality of the pellets. According to experience, the powder content distribution of general livestock and poultry pellet feed as follows:
- Above 3mm-----------No more than 1%
- More than 2 mm----------no more than 5%
- More than 1 mm----------about 20%
- More than 0.5 mm----------about 30%
- Above 0.25 mm----------about 24%
- Above 0.25 mm----------Not less than 20%
The fine material with a small particle size can fill the gaps between the pellets with a larger particle size to improve the quality of the pellets. However, if the pellet diameter required to be produced is smaller, the particle size of the powder is required to be finer.
5. Cooling
The effect of cooling on pellet quality is about 5%. The quality of the cooling effect will have an impact on whether the particles meet the cooling requirements (reduction and precipitation), and whether there are cracks on the surface.
How to improve the quality of granules and reduce powder in the animal feed pellet machine pelleting process:
- Emphasize quality;
- Improve the fineness of powder;
- Reduce output;
- Sharpen the cutter and adjust the position of the cutter;
- Add binder;
- Adjust the formula;
- Increase the aspect ratio of the die
- The power consumption of the animal feed pellet machine accounts for about 30% of the total power consumption of the feed factory. The three key operating parameters of the animal feed pellet machine are effectively controlled to reduce the power consumption in the production process and save power costs.
- Effectively control the amount of steam (in theory, the amount of steam used should be less than 5% of the total granulation) and steam quality (ensure granulation efficiency and pellet quality, reduce raw material loss), ensure the continuous production of the animal feed pellet making machine, and finally avoid wasting steam costs.
- Ensure the quality (warranty, service life, wear resistance, etc.) of the animal feed pellet mill ring die and other accessories to reduce the cost of use. Note that even if they are all stainless steel ring dies, the quality varies from manufacturer to manufacturer and requires careful evaluation.
- Reasonably control maintenance costs. The failure of the animal feed pellet maker should be mainly to prevent, supplemented by repair. Through the perfect routine maintenance process, the failure rate can be greatly reduced and the normal production can be ensured.
- Speed up the upgrading of animal feed pelleting equipment. We should actively adopt animal feed pellet mills that can save energy, reduce consumption, and have low operating costs, especially for those feed production lines and equipment that have been in operation for many years, with high energy consumption, low productivity, and poor safety performance. We should increase the intensity of technical transformation and reduce the overall cost of production.
- Pay attention to cultivating the ability of operators of animal feed pellet manufacturing machine. The quality of the staff in the feed production factory determines the cost and quality of the feed production process in the animal feed factory. Among them, the level of personnel operating level of the animal feed pellet machine directly affects the efficiency of the feed pelletizing mill and the cost of feed processing.
The animal feed pellet production process is carried out in accordance with certain design specifications according to the animal feed production scale, raw material varieties, and product types. Compared with the powder feed production process, the pellet feed processing technology is based on the raw material receiving and pretreatment, grinding, batching, mixing and other processes, adding a pelleting system.
General feed mill pelleting system includes powder conditioner, animal feed pellet milling machine, pellet cooler, animal feed hammer mill, grading screen and packaging machine, etc. The production process of aquatic pellet feed often also includes an extruded part, and the corresponding feed equipment includes powder conditioner, extruder, maturer, dryer, cooler, etc.
