First experience on the CO 2 capture from air

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1 VTT TECHNICAL RESEARCH CENTRE OF FINLAND LTD First experience on the CO 2 capture from air Cyril Bajamundi, Juho Kauppinen, Jere Elfving cyril.bajamundi@vtt.fi NeoCarbon Energy Project WP 5 Task

2 Lab Scale Tests Results

3 Fixed bed adsorption set-up Gas Mixer: Environics S-2000 FTIR: Gasmet DX4000 Humidifier: Hovacal digital 122-SP Gas mixtures: CO 2 /N 2, CO 2 /(N 2 +O 2 ), CO 2 /N 2 + H 2 O, CO 2 /(N 2 +O 2 ), + H 2 O CO 2 is kept at 400ppm N 2 /O 2 = 79 vol /21 vol ratio 2/17/2016 3

4 1. Effect of humidity to adsorption of CO 2 In our lab-scale set-up, we found that there is improvement in CO 2 capacity at T=25 C, 15% RH Dry (0.53 mmol CO 2 /g ads, a.r.) Humid (0.70 mmol CO 2 /g ads, a.r.) 17/02/2016 4

5 1. CO 2 -Amine Chemistry : 1 and 2 Amines - dry Nucleophilic attack of amine with CO 2 forming an internal salt, followed by internal proton (H + ) transfer to form carbamic acid Notoriously unstable towards hydrolysis Reaction of carbamic acid with the second amine to form ammonium carbamate salt This chemistry mandates the need for 2 amine groups with 1 CO 2 molecule 17/02/2016 [Wu, Y., 2011] 5

6 1. CO 2 -Amine Chemistry : 1 and 2 Amines wet Nucleophilic attack amine with CO 2 forming an internal salt (zwitterion) In the presence of H 2 O, the zwitterion can be deprotonated by hydroxyl ions 17/02/2016 [ Didas, S., et al., 2012 ] 6

7 2. Adsorption of H 2 O Method of analysis: Approximation of inlet concentration using pseudosaturated assumption at outlet of the column after some sufficiently long period. Approximated inlet H 2 O concentration 4800 ppm We will assume that in this region* the resin is saturated and use the mode** concentration as the concentration of H 2 O in the inlet gas. Capacity: 1.72 mmol H 2 O/g ads a.r. * The region is selected to be the last quarter of the entire adsorption range. ** Mode is chosen to ensure that the number of (C in -C out )< 0 is minimal. 2/17/2016 7

8 2. CO 2 vsh 2 O adsorption capacity Condition: 400 ppm CO 2 /N % H 2 O H 2 O/CO 2 ratio = 2.45 The CO 2 scrubber can supply at least half of the H required for the Sabatier reaction. Increasing the relative humidity of the gas mixture may further increase H 2 O capacity. 2/17/2016 8

9 3. Effect of O 2 to CO 2 capacity CO 2 conc. [ppm] CO 2 conc. [ppm] Capacity : 0.49 mmol CO 2 /g ads a.r. >> O 2 decreases the capacity approx. 7.5% at dry condition Capacity : 0.67 mmol CO 2 /g ads a.r. >> O 2 decreases the capacity approx. 4.3% at humid condition 2/17/2016 9

10 Bench Scale Tests Results

11 The set-up [ Not for distribution] 2/17/

12 Adsorption / Desorption Cycle T feed = 16 C T out = 18 C T reg = 70 C 90 C P vac < 10kPa Schematics of the adsorption process 2/17/

13 Adsorption Step ppm 75 ppm 2 ~ 5 hrs 3 Unexpected adsorption behavior 4 Negligible capture of O 2 2/17/

14 Adsorption Step ppm 75 ppm 2 ~ 5 hrs Different than in Negligible capture of O 2 4 2/17/

15 Adsorption of CO 2 Adsorption Cycle Recall: Klinkenberg approximation Adsorption Cycle c c F erf Breaktrough curve. Concentration of the solute at the end of the bed as a function of time. Side View of the cartridge 2/17/

16 Desorption step What are we getting? Asymetric stretching Asymetric stretching + other modes Bond bending [1] 2/17/2016 [2] 16 * approx. 1,75 x the rated capacity

Desorption step What are we getting? CO 2 : 37.9mol* (97% max purity) H 2 O: 10.8mol [1] http://webbook.nist.gov/cgi/

17 Desorption step What are we getting? CO 2 : 37.9mol* (97% max purity) H 2 O: 10.8mol [1] 2/17/2016 [2] 17 * approx. 1,75 x the rated capacity

18 Desorption Step What are we getting? Heavy Hydrocarbons 2/17/

integration with other heat/cooling sources Larger buffer

19 The 2nd Phase 8 cartridges Provisions of measurements in the adsorbent bed and H 2 O line Provisions for integration with other heat/cooling sources Larger buffer tank More powerful compressor Address C 9 -C 10 presence 2/17/

How do we proceed in FP2? SOLETAIR From the Sun and Air WP 2: CO 2 capture Task 2.1 Understanding Adsorption/Desorption Cycles Task 2.2 Operation and design retrofit Task 2.

20 How do we proceed in FP2? SOLETAIR From the Sun and Air WP 2: CO 2 capture Task 2.1 Understanding Adsorption/Desorption Cycles Task 2.2 Operation and design retrofit Task 2.3 Seasonal operation studies NeoCarbon Energy Project Task 5.3 CO 2 capture (VTT&LUT) What are the optimum properties of CO 2 adsorbents and how can we synthesize it? How do we capture CO 2 from concentrated source? How does CO 2 capture from air behave at varying weather conditions in Finland? Energy efficient DAC for CO 2 Optimal system control methods 2/17/

21 TECHNOLOGY FOR BUSINESS

EXECUTIVE SUMMARY. especially in last 50 years. Industries, especially power industry, are the large anthropogenic

EXECUTIVE SUMMARY. especially in last 50 years. Industries, especially power industry, are the large anthropogenic EXECUTIVE SUMMARY Introduction The concentration of CO 2 in atmosphere has increased considerably in last 100 years, especially in last 50 years. Industries, especially power industry, are the large anthropogenic