污泥颗粒与河砂混合流化特性的实验研究

The Minimum Fluidization Characteristics of Mixture of Sludge Pellets and River Sand in a Fluidized Bed

在内径φ105 mm、高800 mm的冷态流化床实验装置上进行了污泥颗粒与河砂混合流化特性的实验研究,获得了污泥颗粒水分、污泥颗粒与河砂的质量比对混合物料的流化特性的影响规律．实验结果表明,污泥颗粒的水分、污泥颗粒与河砂的质量比会影响混合物料的最小流化速度,也影响污泥颗粒与河砂混合的均匀程度．污泥颗粒的质量比越大,混合物料的最小流化速度越大;污泥颗粒的水分含量越高,混合物料的最小流化速度也越大;污泥颗粒与河砂的质量比越接近1∶1,越容易实现充分混合．在对实验数据进行分析处理的基础上,提出了污泥颗粒与河砂混合物料的最小流化速度经验方程,为流化床污泥颗粒干燥工艺提供基础数据和设计依据．

The experimental study was carried out in a fluidized bed of 105 mm in diameter and 800 mm in height to determine the minimum fluidization velocity and mixing characteristics. The results show that the minimum fluidization velocities and mixing are affected by the mass fraction of sludge pellets and fiver sand. The more the sludge pellets in the bed, the greater the minimum fluidization velocity, the mixing is the best when the mass fraction of sludge pellets in the mixture is close to 1：1, the more the moisture in the sludge pellets, the greater the minimum fluidization velocity of mixture. Based on the experimental data, a correlation of the minimum fluidization velocity of the mixture of sludge pellets and fiver sand is proposed. The research results can be reference for the design of bubbling fluidized bed sludge dryers.