Measurement of Dense Gas­solids Flow in the CFB riser Using Electrical Capacitance Tomography

Xueyao Wang1, Jing Lei2, Shi Liu2, Liangliang Liao1, Zepu Wang2, Jiachang Wang1, Shengdian Wang1, Yunhan Xiao1*

1. Key Laboratory of Advanced Energy and Power, Chinese Academy of Sciences (Institute of Engineerin Thermophysics), Beijing 100190

2. School of Energy &Power Engineering, North China Electric Power University, Changping District, Beijing 102206

ABSTRACT

The distribution of the void fraction in a circulating fluidize bed (CFB) plays a vital role in the heat and mass transfer. Owing to the advantages such as the high speed, low cost, high safety, easy implementation and non­intrusive sensing, electrical capacitance tomography (ECT) is considered as a promising process tomography. In this paper, ECT technology is employed to measure the void fraction of the riser and the feed­back pipe in a cold CFB and investigate the complicated flow patterns. Encouraging results and typical flow patterns are observed. The measurement results are in well agreement with the real data, which indicate that the ECT technology is competent for the measurement of the void fraction in a CFB.

Keywords electrical capacitance tomography system, CFB, gas­solid two phase flow, relation analysis