Why doesn't the modulation temperature go up?
Why is the modulation temperature not up to the requirements? Is it all due to the pelleting operation?
Modulation temperature is an important parameter in pelleting process. Also with the modulation time, modulation moisture called pelleting three elements. Curing of materials by modulation temperature; Steam and material hydration; The effect of material modulation has an important influence.
First of all, let's look at how many degrees the modulation temperature can be adjusted to from the perspective of the baseline moisture of the pelletizer;
Here to explain, about the control of water conditioning and quenching of aquatic extruding material: the water of the material after quenching and tempering into the extruding machine, floating material 20 ~ 25%; Submerged material 28 ~ 32%. Control of tempering temperature: 90 ~ 96℃ for submerged material and 98 ~ 104℃ for floating material. Therefore, water refill V2(kg/h) directly in the modulator is required. Other mixed feeds do not have direct water replenishment, but if molasses is added, V2 needs to be considered;
By formula design, the moisture of the raw material before the modulation is controlled. The moisture before the modulation affects the heat exchange characteristics of the steam modulation, and also affects the final modulation moisture; 11%-13% of raw material, 15%-17% after quenching and tempering, there is a large steam modulation space;
Equipment adjustment to achieve full heat exchange; The structure of the modulator plays a decisive role in the mixing of steam and material. The steam injection volume should be small at both ends and large in the middle. The material in the conditioner should be thrown up under the action of the slurry blade, and fully contact with the steam to improve the quenching and tempering effect; Condensate water in the pipe should be drained before steam enters the conditioner. Common modulation equipment are: single shaft paddle type adjuster, two, three multi-layer adjuster, steam jacket adjuster, biaxial differential adjuster, kettle type adjuster, high and low speed mixed insulation adjuster.
It is worth mentioning that: the modulator can make the material and steam mixed more evenly, increase the heat exchange efficiency, can improve the modulation temperature help;
Improvement effect of steam on material modulation temperature;
The steam supplied to the quenching and tempering equipment must be high-quality steam without condensate to prevent clogging of the ring die. The steam should be adjusted by low pressure to enter the quenching and tempering equipment at appropriate pressure. The amount of steam should be easily controlled and commensurate with productivity. Appropriately increasing steam pressure can effectively improve the heat transfer efficiency of materials and improve the modulation temperature.