1. Athina Kouneli
Supervisor: Mathias Cehlin
Examiner: Taghi Karimipanah
2016
Faculty Of Engineering
And Sustainable
Development
Master Programme in
Energy Engineering,
Energy Online
Thesis Project

2.  Enviromental factors
(greenhouse effect)
 Financial factors (CO2
trading)

3. Kyoto Protocol
CO2 emissions reduction target for EU
compared to 1990
 1st commitment period (2008-2012) 8%
 2nd commitment period (2013-2020) 20%
Paris Agreement
Global climate deal, to enter in force in 2020

4. Source: Eurostat
EU 2013
Power plants

5.  Capture (plants)
 Transport
Pipelines, ships etc.
 Storage
Geological formation

6.  Present & compare CO2 capture technologies
 Select and analyze CO2 capture with absorption
 Examine the biphasic solvents as alternative option to
classic amines – Energy saving
Literature review
 Scientific papers, patents, educational sites
 Selection of app. 50 references / app. 100 references

7.  Post combustion (separated from fuel gas
compounds)
 Pre combustion (fuel production without carbon)
 Oxyfuel combustion (combustion rich in O2)

8. CO2 is captured from the exhaust gases of a
combustion process. The carbon dioxide is
then compressed and transported and stored.
Capture methods
 Absorption
 Adsorption
 Membranes

9. •Physical absorption (high concentration of CO2, at high
pressures), physical solvents, less regeneration energy
•Chemical absorption, aqueous alkaline solvent (usually
amine)
25-30% net power
output of a coal
power plant is
used for the
solvent
regeneration

10. CO2 molecules adhere to solid sorbents with
high surface area (e.g. zeolites) 
intermolecular forces  CO2 is separated
from the flue gases
1. Flue gas enters a bed of solids
 adsorb only CO2
2. Regeneration of the bed when
fully loaded (reducing
pressure/raising the
temperature)
& (repeated cycle)

11. “A barrier film that allows selective and
specific premeation under conditions
appropriate to its function”
 Gas permeation membranes
Driven force: differences in physical & chemical interaction,
Differences on CO2 partial pressure
 Absorption membranes
Driven force: absorption liquid selectivity

12. 1.The fuel is converted into a mixture mainly of H2 and CO2
CO2 capture from natural gas
 Steam reforming - heat supplied from outside the reformer
 Partial oxidation (incl. Autothermal reforming) – heat is
generated within the reformer
CO2 capture from coal
 Integrated Gasification Combined Cycle (IGCC),
2. CO2 is captured (usually physical/chemical absorption)  CO2
stream (needs compression & dehydration) and a fuel rich in
H2 (boilers, furnaces, gas turbines, fuel cells)

13. CH4 + H2O CO + 3H2
CO + H2O CO2 + H2
heat
Source: Davy technologies

14. Source: BBC

15. Oxygen instead of air during combustion 
Flue gas mainly consisting of CO2 and H2O
Pros
 After the condensation of water high CO2
concentration (80-98%), easy to compress and dry
CO2
 Dilution of the flue gases because of N2 is avoided
Cons
 High cost due to the oxygen production in
cryogenic air separation units
 High temperatures (the flue gas is recirculated to
control the boiler temperature)

17. Most promising option to be implemented on large scale in the near future
taking into account:
 operating & maintenance costs
 cost and ease of retrofitting a power plant
 development of each technology
 Absorption separation technology (Notz et al., Aaron et al.)
Major advantages
 Well established process
 Low complexity
 Load flexibility
Main challenge
 High energy demand for solvent regeneration and CO2 compression – 3.7
GJ/tonCO2 for monoethanolamine (MEA) regeneration
Biphasic solvents as alternative option???

18. After CO2 absorption they form two different
phases, one rich in CO2 and one poor in CO2
 only the rich phase is regenerated
less energy used for regeneration (MEA as
comparison basis)
Biphasic solvents can exhibit:
- two liquid phases
- liquid and solid phase

19.  Phase change mixed amine solvents
TETA DEEA (Ye et al.,2015) app. 30% energy reduction
DEEA MAPA (iCap project) app. 40% energy reduction
 Thermomorphic biphasic solvents
App. 35% energy reduction (Zhang et al.)
 DMX solvents
App. 22% energy reduction
 3H self-concentrating
process
50-80% energy reduction
(Hu, 2012)

20.  TETA/Ethanol Solutions
 Phase change amino acid salts
app. 33% energy reduction
 Chilled Ammonia

21.  Carbon capture processes were presented
 Comparison was made  Carbon dioxide
capture with absorption, the most promising
capture technology to be used in the near
future
 Biphasic solvents > 30% energy reduction in
comparison to simple amines (MEA
comparison basis)

22.  Estimation of captured CO2 cost when using
biphasic solvents
 Comparison with the captured CO2 cost when
using amines
 Research on problems of using biphasic solvents
& how/if they could be avoided

23. Questions?
Contact Information
athina.kouneli@gmail.com