The wet electrostatic precipitator as a cause of mist formation—Results from the amine-based post-combustion capture pilot plant at Niederaussem. (October 2015)

• Record Type: Journal Article
• Authors: Moser, Peter; Schmidt, Sandra; Stahl, Knut; Vorberg, Gerald; Lozano, Gustavo A.; Stoffregen, Torsten; Richter, Torsten
• Is Part Of: International journal of greenhouse gas control. Volume 41(2015:Oct.)
• Page Start: 229
• Page End: 238
• Publication Date: 2015-10
• Subjects: Post-combustion capture -- Amine -- Emission formation -- Emission reduction -- Aerosol -- Wet electrostatic precipitator; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2015.07.010
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: The cause of mist formation by a wet electrostatic precipitator was investigated. Solid nano-particles <300 nm act as nuclei for aerosol formation. Aerosol formation is more complex than a simple SO3 /H2 SO4 -ruled mechanism. The wet electrostatic precipitator can generate ultrafine particles/droplets. PCC emission reduction technologies need to remove aerosol-forming nuclei. Abstract: The investigation of emission formation mechanisms – in particular for aerosol driven mist formation – and also the development and testing of emission reduction measures for amine based post-combustion capture are essential parts of the joint development programme of BASF, Linde and RWE Power at the post-combustion capture pilot plant at Niederaussem. During more than 28, 000 operating hours with BASF's innovative capture technology OASE blue ® several emission mitigation systems have been evaluated under real power plant conditions. A wet electrostatic precipitator (WESP) is often regarded as a suitable option to avoid mist formation. In contrast to this, our investigations have shown that the WESP can cause aerosol formation by increasing the number concentration of ultrafine particles/droplets in the flue gas. Our results also indicate that this highly negative, voltage-dependent effect cannot be explained by a measurable increase of the SO3 concentration downstream of the WESP at the entrance of the CO2 absorber. Varying concentrations of SO2 in the flue gas – which can react to SO3 by ozone that is generated in the high-voltage field of the WESP – does not verifiably influence the entrainment. Low emission levels can be achieved by a special pre-treatment of the flue gas and by the so-called Dry Bed configuration.