一种气、固流化床料位检测的新方法

A NEW METHOD FOR THE MEASUREMENT OF BED HEIGHT IN GAS-SOLID FLUIDIZED BED

料位高度是气、固流化床内重要的基本参数之一。虽然有压降法、测温法、电容法和回波法等可用于料位的测量,但是这些方法作为工业应用都不能令人满意。本文根据流化床内部特性提出了利用流化床内压力波动信号和料面附近的平均压力降测量流化床料位高度的新方法。实验表明,这种方法原理简单,测量精度高。不仅能测量流化床内料位的平均高度。而且还能得到料位的瞬时高度和波动范围;且测量结果不受流化床的几何尺寸、床内物料的特性及流化状态等因素的影响,从而为工业流化床提供了一种料位在线测量的新方法。

Bed height is one of the fundamental parameters in gas-solid fluidizod beds.Although the pressure drop method,temperature difference method,capacitance method and echo method can be used to measure the bed height,these methods are still not satisfactory for many industrial applications.In view of the internal characteristics of fluidized bed,a new method to measure the bed height was proposed on the basis of pressure fluctuation signals inside the bed and the average pressure drop near the bed surface level.Experimental results showed that this method is simple in principle and accurate in measurement.It can be used not only to determine the average bed height, but also the instantaneous bed height and its fluctuation range.Besides,this method is free from the effects of bed size,physical properties of the materials and the fluidized condition in the bed,and thus provides a new method for on-line measurment of bed height of industrial fluidized beds.