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为了对球团干燥过程所涉及的机理获得更好的了解,我们曾对于用西澳大利亚赤铁矿所制成的球团的干燥过程进行了研究。把单个球团放置在工业生产中所具备的典型性温度和气流条件下进行干燥,通过测重、测压、盐份迁移等方法对其进行了试验,并已研制出球团失重及球内内压形成的检测方法。文章报道了球团的干燥行为对于干燥气体的温度、流速及湿度的依赖关系,据发现:球团的干燥过程是按两个连续阶段进行的。最初,球团的干燥包含有水份向其表面迁移且在表面蒸发的过程。其中水份的迁移是由于毛细力作用所致。这一机理导致了干燥速度随时间而下降,并且是球团中60～70%的游离水被脱除的原因;剩下的30～40%的水份是在球团内部蒸发的。正是在干燥过程的这一阶段里,由于球团内部积累了过大的压力,因此有可能使球团爆裂。由提出的干燥机理,我们建议了几种改善球团干燥行为的方法。
To gain a better understanding of the mechanisms involved in the pellet drying process, we have studied the drying process of pellets made from hematite in Western Australia. A single pellet is placed under typical conditions of temperature and air flow used in industrial processes for drying. The pellets are tested by means of weight measurement, manometry, salt migration and the like. Pellets have been developed for weight loss and ballistic The formation of the pressure detection method. The paper reports the dependence of the pellet drying behavior on the temperature, flow rate and humidity of the drying gas. It has been found that the pellet drying is carried out in two successive stages. Initially, pellet drying contained moisture migrating to its surface and evaporating on the surface. The migration of water is due to the capillary action. This mechanism causes the drying rate to decrease over time and is responsible for the removal of 60-70% of the free water in the pellets; the remaining 30-40% of the water is evaporated inside the pellets. It is during this phase of the drying process that the pellets may burst due to the excessive build-up of pressure inside the pellets. With the proposed drying mechanism, we suggest several ways to improve pellet drying behavior.