ABSTRACT

Using coal as feed material and sodium chloride (density and size same as high ash-containing particles in coal feed) as a tracer, residence time distribution (RTD) studies have been carried out in air table. Residence time of particles plays a key role pertaining to density wise segregation on air table. Parameters i.e. air flow rate, side tilt and vibration frequency have strong effect on residence time of particles on air table so their effect was studied using tracer technique. Experimentation was carried out and RTD curves were obtained to find the effect of said parameters on residence time of particles. The residence time of tracer particles increased and span time decreased with increase in the air flow rate, vibration frequency and side tilt. Simulating fundamental force balance equations, explanation of parameters effect on residence time was done. Using dispersion mathematical model, simulated RTD curve was calculated for low air flow rate and validated with the experimental results.

摘要

以煤为原料，氯化钠（密度和尺寸与煤料中的高含灰颗粒相同）作为示踪剂，在空气表中进行了停留时间分布（RTD）研究。颗粒的停留时间对空气台上的密度分离起着关键作用。空气流量、侧倾角和振动频率等参数对颗粒在空气台上的停留时间有很大影响，因此采用示踪技术研究了它们的影响。进行实验并获得RTD曲线以发现所述参数对颗粒停留时间的影响。随着空气流速、振动频率和侧倾的增加，示踪粒子的停留时间增加，跨度时间减少。模拟基本力平衡方程，解释了参数对停留时间的影响。使用弥散数学模型，计算了低空气流量的模拟RTD曲线，并与实验结果进行了验证。