Evaluation of Reduction of Amine Particle Phase Using a Bench-Scale Plant on Amine Emissions

Toshiba has constructed a 10 ton-CO2/day scale pilot plant (CO2 capture Pilot Plant at Mikawa coal- and biomass-fired thermal power plant), and it is found that amine vapor and micro-order amine mist are in existence in flue gas at the outlet for the CCS plant test. Additionally, it is confirmed that the mass of amine mist is larger than that of amine vapor and have a great influence on amine emission. However, it is very difficult to reduce the amount of amine mist with conventional method like a packed bed tower. In this study, we have designed and constructed a bench-scale plant and evaluated effective countermeasures to reduce amine mist for mitigation of amine emissions. Firstly, we have confirmed how the test conditions affected characteristics of amine mist in mist generation section. Then we could succeed in generating simulated amine mist like the actual amine mist derived from MEA or TS-1 at the outlet of the absorber tower in Mikawa pilot plant. Secondly, we have prepared two demister sets (coarse and fine) with two different diameters for each and measured number concentration of amine mist in this mist reduction section. Then the mist removal efficiency of fine demister is very high compared with that of coarse demister. Additionally, the removal efficiency of over 1 μm is approximately 99% in the case of fine demister. Finally, we have checked pressure drop regarding gas velocity passing through a coarse or fine demisters. As a result, the value of pressure drop with fine demister was about ten times as large as that of coarse demister.