Low energy packed tower and caustic recovery for direct capture of CO2 from air

• We used a 6.5 m tall packed tower prototype to study the capturing rate of CO2 from air. The tower was operated at a pressure drop of less than 27 pa in the packing at 0.7m/sec air speed with a counter current flow mode and with NaOH or KOH solution as the absorbent. The tower consumed an average of ~30 kJe per mole CO2. We found that via an intermittent operation with a 5% duty cycle, the fluid pumping work reduced by 90%. A novel process for removing carbonates ions from alkaline solutions based on titanate compounds is compared to the traditional lime cycle for the caustic recovery. The titanate process reduces the high-grade heat requirement by ~50%. The results from experimental data of leaching andprecipitation test support process design of the titanate cycle. In this paper, we also present the chemical process design.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik -- Kemiska processer (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering -- Chemical Process Engineering (hsv//eng)

Nyckelord

air capture

titanate

precipitation

packed tower

direct causticization

leaching

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)