Concomitant removal of NOx and SOx from a pressurized oxy-fuel combustion process using a direct contact column
Journal article, 2018

The simultaneous removal of NO x and SO x using a direct contact column has potential for efficient treatment of the flue gases arising from pressurized oxy-fuel combustion. This study focuses on a parametric analysis of the efficiency of NO x and SO x removal from the flue gas of an oxy-fuel combustion process using an Aspen Plus direct contact column model. The chemistry implemented in this model reflects the state-of-the-art NO x and SO x reaction mechanisms, with particular emphasis on the liquid-phase chemistry, including pH-dependency. The effects of pressure, water flow rate, and recycle ratio on the removal efficiencies of NO x and SO x were evaluated. The evaluation was conducted based on the base case pressurized (15 bar) flue gas with a feed rate of 120 kg/s and inlet temperature of 40 °C before it was supplied to the column. NO x removal efficiency increased from 70% to 97% when the pressure increased from 15 bar to 30 bar, whereas 99.9% of the SO 2 was absorbed from the flue gas at 15 bar. We show that the removal efficiency is pH-sensitive and it is directly influenced by the recycle ratio and liquid-to-gas ratio (L/G). As the L/G ratio was increased, the removal efficiency of SO x and NO x increased. On the other hand, when the recycle ratio of bottom liquid was increased, the removal efficiency of SO x and NO x decreased.

Pressurized combustion

NOx

Emissions

SOx

Oxy-fuel combustion

Author

Tefera Zelalem Tumsa

Korea Institute of Industrial Technology Evaluation and Planning

University of Science and Technology (UST)

See Hoon Lee

Chonbuk National University

Fredrik Normann

Chalmers, Space, Earth and Environment, Energy Technology

Klas Andersson

Chalmers, Space, Earth and Environment, Energy Technology

Sima Ajdari

Chalmers, Space, Earth and Environment, Energy Technology

Won Yang

University of Science and Technology (UST)

Korea Institute of Industrial Technology Evaluation and Planning

Chemical Engineering Research and Design

0263-8762 (ISSN) 1744-3563 (eISSN)

Vol. 131 626-634

Subject Categories

Energy Engineering

Chemical Process Engineering

Bioenergy

DOI

10.1016/j.cherd.2017.11.035

More information

Latest update

5/31/2018