0.5 MWth 케미컬루핑 연소시스템 적용을 위한 산소전달입자의 수력학 특성 및 고체순환 특성

Hydrodynamics and Solid Circulation Characteristics of Oxygen Carrier for 0.5 MWth Chemical Looping Combustion System

Abstract

To select the operating condition of 0.5 MWth chemical looping combustion system, minimum fluidization velocity, transition velocity to fast fluidization and solid circulation rate were measured using mass produced new oxygen carrier (N016-R4) which produced by spray drying method for 0.5 MWth chemical looping combustion system. A minimum fluidization velocity decreased as the pressure increased. The measured transition velocity to fast fluidization was 2.0 m/s at ambient temperature and pressure. The measured solid circulation rate increased as the solid control valve opening increased. We could control the solid circulation rate from 26 to $93kg/m^2s$. Based on the measured minimum fluidization velocity and transition velocity to fast fluidization, we choose appropriate operating conditions and demonstrated continuous solid circulation at high pressure condition (5 bar-abs) up to 24 hours.

Fig. 1. Conceptual diagram of chemical looping combustion system

Fig. 2. Microscopic image of N016-R4 particle (fresh)

Fig. 3. Two-interconnected high pressure fluidized bed system, (a) schematic, (b) 3D-view

Fig. 4. Trend of bed pressure drop versus gas velocity (how to determine the minimum fluidization velocity)

Fig. 5. Effect of pressure on the minimum fluidization velocity

Fig. 6. Trend of emptying time versus gas velocity at ambient temperature and pressure (how to determine transition velocity to fast fluidization)

Fig. 7. Effect of solid flow control valve opening on the solid circulation rate

Fig. 8. Trends of pressure drop profile in the two-interconnected circulating fluidized bed system

Table 1. Properties of oxygen carrier particles

Table 2. Summary of location of each differential pressure transducer