ESA modelling and cycle design

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Vernon Walker
5 years ago
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1 ESA modellng and cycle desgn WP and WP 5 Unversty of Belgrade MATESA Dssemnaton day, Oslo

2 Motvaton Develop rgorous 3D models (CFD) to understand the processes, examne the nfluence of condtons / parameters and have a bass for model reducton Develop smplfed 1D models for cycle smulatons, wth model parameters estmated based on 3D smulatons Desgn ESA cycle that wll satsfy demands for hgh Purty (P>95%) and Recovery (R>90%) Analyze electrc energy consumpton and relatons to P and R Analyze optons to reduce the electrc power consumpton by means of heat recovery and use of exstng thermal power Relate the results to expermental data

3D modellng Monolth geometry and ¼ of a annel for 3D

Detaled 3D modelng of adsorpton / desorpton n sngle annel

non-statonary multcomponent mass transfer (dffuson),

3 3D modellng Monolth geometry and ¼ of a annel for 3D modelng Model mesh Adsorpton and desorpton smulatons Detaled 3D modelng of adsorpton / desorpton n sngle annel of the monolth n Comsol Multphyscs Man model features: non-statonary multcomponent mass transfer (dffuson), compettve adsorpton sotherms, lamnar flow momentum balance and Joule heatng

4 Adsorpton sotherms CO N and O Compettve adsorpton Langmur model Based on expermental masurements for zeoltecarbon monolth (WP-4) Temperature dependence of q 0 and b obtaned q = q0, N 1+ b j= 1 P b j P j

(adsorbent) at certan poston and tme Gas temperature

5 3D smulatons - results CO concentraton n gas (annel) at certan poston and tme CO concentraton n sold (adsorbent) at certan poston and tme Gas temperature at certan poston and tme Sold temperature at certan poston and tme

6 3D results effect of parameters CO breakthrough curves Influence of gas velocty and geometry Influence of dffuson coeffcents n sold Desorpton Influence of competng adsorbates (ncludng water) Influence of electrcal potental

7 1D modellng Smplfed model developed for the purpose of cycle desgn, smulatons and analyss The model conssts of non-statonary 1D materal, energy and momentum balances for the gas phase (annel) and monolth wall mass and energy balance Implemented n gproms The 3D model smulaton results used as numercal experments for estmaton of the 1D model parameters model reducton study

8 3D to 1D model reducton 3D smulatons under varous condtons to estmate the key 1D model parameters new correlatons derved ( ) ( ) b c ax c a a a t q C L 1 C D L 1 t C + = ρ ς υ ς ς ( ) q q k t q * = ( ) ( ) s g p,g g g c g p,g g axh c g p,g g T T h c T L 1 T c D L 1 t T c = ς ρ υ ς ρ ς ρ ( ) ( ) ( ) ( ) ( ) c a n b s g s s c s s p b L a a I U t q H a a a T T h T L t T c = = 1, 1 ρ ς λ ς ρ

9 1D smulatons and valdaton Valdaton based on a) lterature expermental data b) numercal 3D experments

actvated carbon adsorpton columns and cycle Addng rnse step (), dvdng electrfcaton

10 ESA cycle buld-up Smplest cycle wth adsorpton (1), desorpton wth electrfcaton () and coolng (3) s far from satsfyng P and R Important: Water s removed n separate actvated carbon adsorpton columns and cycle Addng rnse step (), dvdng electrfcaton to steps (3 and 4) and addng purge step (5) ncreased P to 91.5% and R to 79.% - stll not enough

11 ESA cycle to rea P and R Crucal step for reang R s the recycle step, n wh CO that remaned n the bed (new purge step 8) s returned to adsorb (before electrfcaton ) P s aeved by ntroducton of one more step durng electrfcaton (5) Coolng tme s reduced as only 70% of the monolth s cooled to feed temp.

12 ESA cycle framework n gproms

61h Adsorpton: 3.87hr 69% of total tme Total regeneraton: 1.

13 ESA cycle results long column (13X/carbon composte, 00 cps) Purty = 95.40% Recovery = 90.0% Column legth 1m Total cycle tme 5.61h Adsorpton: 3.87hr 69% of total tme Total regeneraton: 1.74 h 31% of total tme Electrfcaton: 0.8h 5% of total tme Coolng: 1.8 h 3% of total tme

14 Results n numbers Total feed flow rate [Nm 3 /s] Inlet CO fracton [%] 3.5 Maxmal sold temperature [K] 480 CO recovery rate [%] 90.0 CO purty [%] 95.4 Mass of adsorbent n 1 column [t] 348 Total number of columns (1m long, 7.4m wde) 60 Total cycle tme [h] 5.61 Adsorpton tme per total tme [%] 69 Specfc energy consumpton [GJ/t CO ] 4.41

15 Energy cost for reang R and P If R and P are lower electrc energy consumpton decreases consderably: Space-average T durng desorpton [K] Purty [%] Recovery [%] Specfc energy consumpton [GJ/t CO ]

16 ESA cycle results short column Purty =96.3 % Recovery =87.5 % Column length.9 m Cycle tme 1.43 h Adsorpton: 0.89 hr 6 % of total tme Total regeneraton: 0.54 hr 38 % of total tme Electrfcaton: 0.15 hr 10.5 % of total tme Coolng: 0.33 hr 3 % of total tme

17 Results n numbers Total feed flow rate [Nm 3 /s] Inlet CO fracton [%] 3.5 Maxmal sold temperature [K] 480 CO recovery rate [%] 87.5 CO purty [%] 96. Mass of adsorbent per column [t] Total number of columns (3m long, 7.4m wde) 60 Total cycle tme [h] 1.43 Adsorpton tme per total tme [%] 6 Specfc energy consumpton [GJ/t CO ] 4.6

18 ESA cycle heat ntegraton N TANK CO TANK TANK Heat ntegraton wthn the cycle and wth the water removal unt Heat ntegraton wth low-grade steam from the power-plant The specfc energy consumpton expected to drop to.5 GJ/t CO

19 Summary Wthn MATESA project, models for ESA process, sutable for complex cycle smulatons and optmsaton, have been developed and exploted The ESA cycle smulatons show that the requrements of hgh purty (>95%) and recovery (>90%) can be aeved, though through complex cycle desgn wth a number of steps and recycles The results ndcate that the ESA process based on zeolte or MOFcarbon composte monolths can be an alternatve to absorpton based processes for CO capture Further mpovements trough further materal development and optmsaton and energy ntegraton are foreseen

modeling of equilibrium and dynamic multi-component adsorption in a two-layered fixed bed for purification of hydrogen from methane reforming products

modeling of equilibrium and dynamic multi-component adsorption in a two-layered fixed bed for purification of hydrogen from methane reforming products modelng of equlbrum and dynamc mult-component adsorpton n a two-layered fxed bed for purfcaton of hydrogen from methane reformng products Mohammad A. Ebrahm, Mahmood R. G. Arsalan, Shohreh Fatem * Laboratory