关键词: 鼓泡塔, 反应器, 流化床, 化学链燃烧, 气固流动, 压力测量

Abstract:

Chemical looping technology is now limited by its insufficient fuel conversion and inefficient carbon capture. To solve such critical issues, a novel chemical-looping combustion (CLC) system for tower bubbling fluidized bed was designed. The whole loop system consisted of a tower fuel reactor (FR), an air reactor (AR), two loop-seals (LS), two cyclone separators, two risers and two down-comers. In cold model studies, methods of pressure measurement and outlet gas detection were applied to investigate the flow characteristics under different fluidization numbers, including pressure distribution, gas-solid distribution, solid circulation rate, and gas leakage. The results showed that the pressure balance in the system was guaranteed by the loop-seals. The FR fluidization number should be controlled between 3.5—4.0, which could guarantee a good gas-solid distribution in the FR, and lower the pressure loss between baffles. The solid circulation rate in the system was proportional to the pressure drop in the riser with a maximum of 0.013kg/s, and was mainly influenced by the fluidization number in reactors. The gas leakage from loop-seals to reactors was around 4%—8%, but there was no gas leakage between the FR and AR, which provided a good experimental basis for the design and operation of the thermal CLC system.

Key words: bubble tower, reactor, fluidized bed, chemical looping combustion, gas-solid flow, pressure measurement