(440e) Main Operating Parameters of the Spouting Regenerator for the Collecting Particles of the Moving Bed Filter

The combustion of fossil fuel inevitably results in serious environmental pollutions such as discharging flue gas containing SO₂, NO₂ and CO₂. Thus efficient flue gas purification techniques, especially for the high-temperature gas purification process, are required to protect the environment as well as the downstream units. The moving bed filter is undoubtedly one of the most effective ways to high-temperature dedust. The collecting particles in moving bed filter are usually anticipated to be used recycling, thereby an effective regenerating method for the collecting particles is particularly needed. That is to say, in a circulating system, the dusts in gas are caught in the moving bed filter and they were separated from the collecting particles in a regenerator sequentially.

In this paper, the spouting regenerating for the collecting particles of the moving bed filter is investigated. The fundamental of spouting regenerator is that the operating lift gas velocity was considerably higher than the delivery velocity of dust while fairly lower than that of the collecting particles.

Therefore, it is necessary to determine the main operating parameters of the spouting regenerator for the collecting particles of the moving bed filter. The experimental research on the regenerating efficiency of the regenerator with the collecting particles containing dust was carried in a large plexiglass cold model experimental setup. The dust-collecting particle mixture was sampled both in the spent collector inclining tube and regenerating inclining tube under different operating conditions. These effects of the operating parameters including the dust-collecting particle ratio, the gas velocity and the circulating particle flux on the regenerating efficiency were investigated, respectively. Besides, the abrasion of collecting particle in the spouting bed was measured. On the other hand, the particle size variation during the regenerating process was also analyzed. By measuring the particle size distribution and the mass frequency of the sampled mixture, the corresponding regenerating efficiency under different operating conditions was obtained. It was found that, the dust-collecting particle ratio, the gas velocity and the circulation flux were all the key operating parameters for regenerating. Increasing the dust-collecting particle ratio and the gas velocity is beneficial to the regenerating efficiency; while increasing the circulating particles flux results in an opposite effect. Moreover, the spouting regenerator can achieve the high separation efficiency under the condition of high lifting gas flow velocity. If the gas velocity too high, however, the collecting particles would also be brought away with the dust and sequentially, the magnitude of the collecting particles decreases. The spouting regenerating process inevitably leads to the collecting particles abrasion and thus a suitable gas velocity is quite vital for the whole regenerating system. Based in the experimental results, the recommended gas velocity is generally 1.1-1.3 times that of the collecting particles.