IGCC with post-combustioncapture using Ca-L process

Rahul Anantharaman, SINTEF Energy ResearchChao Fu, SINTEF Energy Research

Conceptual process flow diagram

Ca‐looping cycle for CO2 capture 

NGCC with Ca‐looping CO2 capture

Systematic efficiency improvement

• Sizing and cost estimation

Modeling of Ca-looping reactors

• Further optimization studies

- Trade-off between solids inventory, fresh makeup limestoneand solid recycle flow

- Trade-off between CO2 capture rate, energy consumption and capital cost

- Scale-up study

- Comparison with other CO2 capture alternatives

- Entire flowsheet optimization

• Applicable to various industrial processes with CaL capture

- Performance prediction

Simplified Ca‐Looping model

Modeling of the carbonator

Reference: M.C. Romano, 2012. Chemical Engineering Science 69, 257-269.

• On the basis of the Kunii-Levenspiel model, and kinetics and capacity models of CaO

• Impacts of sulfuration and ash are included

Simple vs Advanced model

Simple model Advanced model

Phase Gas and solid phase well mixed

Discrete gas and well mixed solid phase

Reaction Instantaneous reaction Kinetic reactions

Sorbent property Average solid conversion Reactor hydrodynamics

Application exampleAverage carbonation level 0.75 (specified) 0.89 (calculated)

Number of units 10 2

Design CO2 capture rate 0.90 ‐

CO2 capture rate using advancedmodel

0.9412 (but the height of the dense zone is ‐4.38 m)

0.8997

Reference: (1) D.P. Hanak, et al. 2015. Energy & Environmental Science 8, 2199-2249.(2) R. Anantharaman, et al. 2014. BIGCCS Deliverable Report D1.6.1410.(3) D. Berstad, et al. 2012. International Journal of Greenhouse Gas Control 11, 25-33.

Modeling of the calciner

• Fewer studies on the modeling of oxy-fuel calciners- Public models can hardly be applied for sizing estimation

- The coupling of carbonators and calciners has less been studied

• Challenges

- Simple models for preliminary calculations are desired

- Validation of the models (insufficient public experimental data)

- Level of details about oxy-fuel combustion reaction