Characterization of Packing Materials for CO 2 Absorption

Transcription

1 1 Characterization of Packing Materials for CO 2 Absorption Ali Zakeri a, Aslak Einbu b, Hallvard F. Svendsen a a NTNU, N-7465 Trondheim, Norway. b SINTEF, N-7465 Trondheim, Norway. Norwegian University of Science and Technology (NTNU) Department of Chemical Engineering Trondheim, Norway

2 2 Outline Introduction. Pressure drop. Liquid holdup. Effective mass transfer area. Conclusions.

3 3 Introduction The aim of the present work is to test three modern structured packing by measuring pressure drop, liquid hold-up and effective mass transfer area as function of gas and liquid load. Focus on intermediate and low liquid flow rates Packings studied: Sulzer, Mellapak 2X, Koch-Glitsch, Flexipak 2Y HC 49 Julius Montz, Montz-Pak B1-250M.

4 4 Geometric data for the different packings Packing model Angle of Packing element Specific surface area inclination height [mm] [m studied 2 /m 3 ] Void fraction [m 3 /m 3 ] Sulzer Mellapak 2X Koch-Glitsch Flexipac 2Y HC Montz-Pak B1-250M

5 5 The VOCC absorber test rig Column ID 0.5 m, packing height 5 m Superficial gas velocities up to 5 m/s BLOWER CYCLONE Liquid flow rate up to 200 l/min 2000 liter holding tanks for batch runs External CO 2 supply (delivers up to 300 kg CO 2 /h) Sensors for column pressure- and temperature profile Gas analyser for CO 2 content in-/out of column Setup for continous measurement of liquid hold-up in ABSORBER GAS COOLER packing Setup for online measurement of CO 2 loading of amine

6 6 Pressure drop Pressure drops were measured based on pressure measurement at 6 positions along the packing height. Position 1 is below the packing, and positions 2-6 are 0.5 m, 1.5 m, 2.5m, 3.5m, 4.5 m into the packing respectively.

7 7 Sulzer Mellapak 2x, Air/Water system (Pa 0.5 )

8 8 Pressure drop in mbar/m as a function of F-factor for two liquid loads for viscosities ranging between 1 and 12cP using sucrose as viscosifier. Sulzer Mellapak 2x a b 5 m 3 /m 2 h 25 m 3 /m 2 h

9 9 Pressure drop in mbar/m as a function of F-factor for two liquid loads for viscosities ranging between 1 and 12cP using sucrose as viscosifier. Koch-Glitsch Flexipak 2Y HC a b 5 m 3 /m 2 h 25 m 3 /m 2 h

10 10 Pressure drop in mbar/m as a function of F-factor for two liquid loads for viscosities ranging between 1 and 12cP using sucrose as viscosifier. Montz-Pak B1-250M a b 5 m 3 /m 2 h 25 m 3 /m 2 h

11 11 Pressure-drop as function of F-factor for the different packings at 5 and 25m 3 /m 2 h liquid load. Air/water Air/sugar soln(5cp) Air/sugar soln(12cp)

12 12 Pressure-drop as function of F-factor for the different packings at 5 and 25m 3 /m 2 h liquid loads. Experiments with 30 wt% MEA/air system. 30 wt% MEA/air system

13 13 Calculated pressure drops using the SULCOL, KgTower and Montz Pak compared with experimental data Mellapak 2X Flexipac 2Y HC Montz B1 250M

14 14 Sulzer Mellapak 2x Air/Water system

15 15 Liquid hold up as function of F-factor for the different packings at low liquid load. Mellapak 2X 5.7m 3 /m 2 h Flexipac 2Y HC 5.0m 3 /m 2 h Montz B1-250M 5.0m 3 /m 2 h

16 16 Liquid hold up as function of F-factor for the different packings at high liquid load(25 m 3 /m 2 h). Mellapak 2X Flexipac 2Y HC Montz B1-250M

17 17 Liquid hold up as function of F-factor for the different packings Air/water Air/sugar soln(5cp) Air/sugar soln(12cp) d Air/30%MEA

18 18 Liquid holdup measured and Liquid hold up from literature vs. F-factor Flexipac 2Y HC Montz B1 250M

19 19 Fractional effective area (ae/ap) as a function of liquid load (m 3 /m 2 h) for three different ranges of superficial gas Absorption of CO 2 in 0.3 M NaOH. Mellapak 2X Flexipac 2Y HC Montz B1 250M

20 20 Fractional effective area (ae/ap) as a function of liquid load (m 3 /m 2 h) for three different ranges of superficial gas Absorption of CO 2 in 30 wt% MEA. α = 0.2 α = 0.3

21 21 Conclusions Pressure drop, liquid hold up and effective mass transfer area were successfully determined in a pilot plant absorber (0.5 m ID, 5.4 m packing height) as function of liquid viscosity and gas and liquid flow rate. The variations of the hydraulic parameters are in reasonable agreement with correlations found in literature for F-factors below 3. A slight influence of viscosity on pressure drop and flooding velocity was found. Increased viscosity has a significant influence on hold-up especially at high liquid loads. Both for NaOH and MEA solutions the active area increases with liquid load up to about 25 m 3 /m 2 h. Gas flow rate has a very small effect on active area. The values of measured effective mass transfer area are close to values found in literature for the NaOH system. Initial evaluation of effective mass transfer area for the loaded MEA systems show a particularly strong influence of liquid load in the low range. Needs further investigation.

22 22 THANK YOU