Effect of various feed production equipment on feed pellet quality
High-quality animal feed pellets can be defined as feed pellets that can withstand repeated operations. For example, feed pellets will not be damaged too much or produce too many fine particles during bagging, transportation, storage and feed line transportation. The pellet quality is usually expressed by the Pellet Durability Index (PDI), and can be measured by a tumbling tank: firstly, the particle sample to be tested is sieved to remove fine powder particles, and then tumbling in the tumbling tank for a certain period of time. The rolled sample is sieved to remove fine particles, and the weight of the complete particles can be obtained.
The animal feed pellet processing line. RM Receiving & Precleaning System—Grinding System—Dosing & Mixing System—Pelleting System—Bagging System—Auxiliary System. Because there are many stages, the quality of the final pellet feed is affected by many factors Yes, today we will talk to you in detail, I hope to help you.
1. Effect of steam system
① Small-scale feed factories often use low-pressure steam boilers. The steam pressure used is generally 0.2~0.4MPa. Steam boilers are also often placed near the feed pellet making machine. Due to their low output, the steam pipe transportation distance is short, and the pellet processing machine ring die aperture Small (generally Φ2~Φ3), so the particle quality is better;
② Due to the high output and large equipment of large-scale feed pellet plants, steam boilers are generally far away from the production workshop, so their delivery pipelines are long (usually several hundred meters), and high-temperature and high-pressure steam are often used to ensure the steam quality of the animal feed pellet mill machine during conditioning. Generally, 0.8MPa and 180°C saturated steam are used.
From our experience, the steam boiler should be placed near the ring die pellet mill, and the length of the steam pipeline should be shortened as much as possible, especially in the north; in addition, the steam boiler should preferentially choose the oil furnace, because the coal furnace is difficult to ensure the stability of the steam pressure. Otherwise, the steam moisture content is high and the steam pressure is unstable, which in turn affects the conditioning effect and the pellet quality.
2. Effect of conditioner
One of our customers, the animal feed pellet making machine(8T/H) used in his feed factory, has a conditioner length of 1.4m. Due to the increase in the variety of alternative raw materials added to the feed in recent years, and the northern The winter weather is cold and the transportation pipeline is long, the conditioning time is too short, the conditioning temperature is low, and the conditioning effect is difficult to guarantee. Therefore, the conditioner we choose for the pellet mill of this customer's feed factory is an enhanced type, to ensure the temperature and time of powder feed conditioning, so as to ensure the quality of pellet feed.
3. The impact of feed pellet mill ring die and pressure roller
Roller gap: The gap should be ensured at 0.05~0.3nm, that is, the ring mold can just drive the pressure roller to rotate as well. When the gap is large, the ability of the wedge-shaped space between the mold rolls to feed the feed is reduced, and the squeeze force of the mold rolls on the feed is reduced. When the pressure is less than the frictional resistance of the inner wall of the mold hole to the feed, the animal granule feed pellet mill machine will block the machine and affect pellet quality.
Generally, it is better to replace the ring die and the pressure roller when pairing it. In normal production, the gap between the die rollers should be adjusted before starting each shift. When using the old ring die and the pressure roller, it should be polished to ensure that the surface is as smooth as possible.
Pressure roller die damage: when checking the granulation, if it is found that the rotation of the pressure roller is inconvenient, it should be replaced in time. Under normal circumstances, when the pressure roller bearing is damaged, it is often the case that the pressure roller cannot rotate normally. Otherwise, the machine will be blocked. Affect the particle quality.
Diameter of die hole and feed cone: Under the condition that the thickness of ring die is constant. When the diameter of the die hole is reduced, the strength of the feed pellets extruded increases, the pellets are neatly shaped, the hardness and density increase, and the pulverization rate decreases. Feed pellets with die holes of Φ2~Φ3 are beneficial for suckling pigs and chicks. Of course, reducing the diameter of the ring die will inevitably lead to a reduction in production efficiency. Therefore, the above factors should be combined to make a reasonable choice.
In addition, if the feed cone of the ring die has been severely worn, the granulation production output and particle quality will decrease. Because at this time, the amount of steam added to the feed is limited (the amount of steam is large, it will block the machine), thereby reducing the temperature of the feed conditioning. Therefore, if the ring die is still available, the feed cone of the ring die should be processed in time to ensure the output and pellet quality.
4. Cooling and chipping effects
① The pellets are cooled uniformly and moderately by feed pellet cooling machine. Nowadays, the pellet cooler is widely used, which has high cooling efficiency and good effect;
② The pellet crushing equipment should be repaired in time when the crushing roller teeth are blunt, otherwise, the crushing effect of the crushing roller becomes stronger, the uniformity of the feed pellets becomes worse, and the pulverization rate increases. During normal production, the gap between the crushing rollers should be properly adjusted according to the type of feed;
③ After crushing the granules, use a plane rotary sieve with a small inclination angle to carry out the screening treatment, especially for large animal feed pellet plant.