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HWAHAK KONGHAK Vol. 38, No. 6, December, 2000, pp. 809-816 (Journal of the Korean Institute of Chemical Engineers) 809 CO 2 PSA * * * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO 2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo Yeo*, Hyung Keun Song and Byung-Ki Na Clean Technology Research Center, KIST, Seoul 136-791, Korea *Dept. of Chem. Eng., Hanyang University, Seoul 133-791, Korea (Received 1 February 2000; accepted 18 September 2000) PSA , . . , . . CO 2 , . . Abstract - The effect of evacuation and rinse step on the process performance was studied using numerical simulation to recover heavy component in a PSA process. Rinse and evacuation steps are very important to obtain heavy component as a product. Therefore, to improve the process performance, the rinse pressure, reflux ratio and flow direction of rinse step were selected as variables, and the performance change of process according to changing variables was investigated. The effect of eva- cuation condition combined with the rinse condition was studied also. As a result, the optimum operating condition was obtained to have maximum process performance. Increasing rinse pressure conduced to increase the recovery by increasing adsorbed amount of CO 2 during the rinse step. Decreasing evacuation pressure contributed to increase the purity by increasing desorbed amount of CO 2 during the evacuation step. At this point, the optimum reflux ratio was existed at certain pressure conditions. Key words: CO 2 , PSA, Rinse, Evacuation, Simulation E-mail: [email protected] 1. PSA 1957-1958 Skarstrom [1, 2] . PSA 1950 . Skarstrom cycle , cycle PSA [2]. 1960 PSA , 1980 , . , [3, 4]. . Skarstrom cycle . Berlin [5] . [6]. ,

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Page 1: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

HWAHAK KONGHAK Vol. 38, No. 6, December, 2000, pp. 809-816(Journal of the Korean Institute of Chemical Engineers)

CO2 ��� �� PSA��� � � ���� �� ��� ��� ��

�������*��*��� ����†

�������� ������ *����� �����

(2000� 2� 1� ��, 2000� 9� 18� ��)

Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery

Hawung Lee, Jae-ho Choi*, Yeong-Koo Yeo*, Hyung Keun Song and Byung-Ki Na†

Clean Technology Research Center, KIST, Seoul 136-791, Korea*Dept. of Chem. Eng., Hanyang University, Seoul 133-791, Korea

(Received 1 February 2000; accepted 18 September 2000)

� �

����� ��� PSA �� , �� � ����� �� ��� ��� ��� ��� � ! "# $%. �

�& ����� ����� "'(� ���) *+ ,- ./- ���%. 01 ����� 23� 4567 ��

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Q� D RS%. ��=>� T�� ��6� ��U� CO2� V� T�67 '(W% XD9� T�� Y 8&� W$

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0G NO� ��?@A� efg� hi D RS%.

Abstract − The effect of evacuation and rinse step on the process performance was studied using numerical simulation to

recover heavy component in a PSA process. Rinse and evacuation steps are very important to obtain heavy component as a

product. Therefore, to improve the process performance, the rinse pressure, reflux ratio and flow direction of rinse step were

selected as variables, and the performance change of process according to changing variables was investigated. The effect of eva-

cuation condition combined with the rinse condition was studied also. As a result, the optimum operating condition was obtained

to have maximum process performance. Increasing rinse pressure conduced to increase the recovery by increasing adsorbed

amount of CO2 during the rinse step. Decreasing evacuation pressure contributed to increase the purity by increasing desorbedamount of CO2 during the evacuation step. At this point, the optimum reflux ratio was existed at certain pressure conditions.

Key words: CO2, PSA, Rinse, Evacuation, Simulation

†E-mail: [email protected]

1. � �

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" �#��� �$% �� &' ()* +,-%. #/0 1�

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u vN� w' ()* T] ��.

QRSG� Skarstrom cycle� xy� w� z{%. �V�| S

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809

Page 2: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

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Fig. 1. Flow schedule of PSA process.PR: Pressurization, AD: Adsorption, CD: Countercurrent depressur-ization, PE: Pressure equalization, RN: Rinse, EV: Evacuation

���� �38� �6� 2000� 12�

Page 3: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

CO2 PSA���� ����� � 811

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Á�[6].

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(1)

where

Mass Balance of i-component:

(2)

Energy Balance:

(3)

Mass Transfer Rate:

(4)

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�G¤¥� Ò SG� ¦4 Table 1� Í& ¤¥� Ñ''�[13].

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6� �3-%. ~6E6. _p#³ 6 �%f �{� Á� #æ�

&' ô6� y�" (�[3].

(5)

where

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´��. ²' G6 a� Rº))� *Ñ' ��" ÍA� +�.�,

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W �R N�. U�SG" ß~�Æ 0�. ²' + ()�� GM

� w�� p�0 <=@� <=� �� &' �t� ¤Ì¤¥� Table2

� ��%f[9], ¶p� p�0 �¢ ã�x6O� � Table 3� �

��.

w�� ��0 ¶ý£O� PSA �� ¶p�� w� �#� $P

ü ��; b�-9 �N� d�J �{� Á� q�. q/-%.

$��$�. ÔÕ £ (4)� <=��£� GM' 2 Î ±� � ���

∂ uCtotal( )∂z

-----------------------∂Ctotal

∂t---------------

ρbulk

ε-----------

∂qi

∂t------- 0=

i 1=

n

∑+ +

Ctotal Cii 1=

n

∑=

∂Ci

∂t-------- u

∂Ci

∂z-------- Ci

∂u∂z------

ρbulk

ε-----------

∂qi

∂t------- 0, i 1= ,…, n=+ + +

ερgCpg ρbulkCps+( )∂T∂t------ ερgCpg( )u∂T

∂z------ ρbulk

∂qj

∂t------- Hj∆

j 1=

n

∑ =0+ +

∂qi

∂t------- ki qi

* qi–( )=

qi

P t( ) C0 C1exp C2t–( )+=

C0 aPts.=

C1 P0 aPts–=

C21 a–( )γ a–( )

-------------- ts⁄ln–=

Table 1. Boundary conditions of each step

Step Concentration Temperature Pressure Velocity

Pressurization yi(t, 0)=yf,i T(t, 0)=Tfeed P=P(t) u(t, L)=0Adsorption yi(t, 0)=yf,i T(t, 0)=Tfeed P=PH u(t, 0)=ufeed

Blowdown P=P(t) u(t, 0)=0Evacuation P=P(t) u(t, L)=0Pressure equalization Depressurized yi(t, L)=yEq T(t, L)=TEq P=P(t) u(t, 0)=0

Pressurized yi(t, L)=yEq T(t, L)=TEq P=P(t) u(t, 0)=0Rinse Pressurized, cocurrent yi(t, 0)=yproduct T(t, 0)=TEv P=P(t) u(t, L)=0

Constant pressure, cocurrent yi(t, 0)=yproduct T(t, 0)=TEv P=PRn u(t, 0)=uOR2

Pressurized, countercurrent yi(t, L)=yproduct T(t, L)=TEv P=P(t) u(t, 0)=0 Constant pressure, countercurrent yi(t, L)=yproduct T(t, L)=TEv P=PRn u(t, L)=uOR2

HWAHAK KONGHAK Vol. 38, No. 6, December, 2000

Page 4: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

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r»¼* 0.759 ��� U�Rº� ¦§ q�m �6�� Í& Î

4%., U�Rº� ��6ø q�m �6�� vNP tuê*òª

� �á NS%. ��E� 8 6 ��. �� U�SG* �� ��

´½� ¾v� d� 8 7 �(' ±�. ��OJT�. Ý, U�S

G� CMb� r»#µ @ A CMb� ��" F*#G%. �� q

�� CMb� c� ­�" *�õ�;, ��' ­�� CO2m N2�

êy<=ï� /�� �� [C'�. êy<=ï� ��N� CO2� �

�m Rº� ��� ±�� �;, ��' CO2� ¤t ���, Rº

� Éd:W l� �� CO2* <=9 6 ��. �� <=�ìª%.�

àá5 6 �� ±�.� Fig. 4� Í& <=�ìª� lW, Rº�

F*� ¦4� <=ï� ��~� 1� 8 6 ��; U��� ��

CO2 ��� !ú��� CO2 ��m Ü� q�� �H� ���Æ

Table 2. Characteristics of adsorption bed and operating conditions

Adsorbent Particle size [mesh] Feed gas composition Bed diameter [mm] Bed height [mm] Adsorbent amount [kg] Bed bulk density [g/cm3] Bed porosity, ε Heat capacity of adsorbent, Cps [J/g/K] Heat capacity of gas, Cpg [J/g/K] Adsorption pressure, PH [atm] Evacuation pressure, Pev [atm] Equalization pressure, Peq [atm] Time for adsorption [s] Time for blowdown [s] Time for pressure equalization [s] Time for rinse/evacuation [s]

Activated carbon8-1217% CO2, in N2

41.29000.570.470.41.050.99421.50.10.553002020360

Table 3. Langmuir parameters and heat of adsorption used in the cal-culation

Parameter CO2 N2

t1* [mmol/g]

t2* [mmol/g]

t3** [atm−1]

t4** [K]

∆H [kJ/mol]

23.944−0.0517

2.1265×10−3

1588.31524.103

7.052−0.0106

4.2169×10−4

1680.03816.928

*qm=t1+t2T**b=t 3 exp(t4/T)

Fig. 2. The effect of flow directions on rinse step.Case (1): cocurrent pressurization by product, cocurrent pressurrinse, Case (2): cocurrent pressurization by product, countercurpressurized rinse, Case (3): countercurrent pressurization by prococurrent pressurized rinse, Case (4): countercurrent pressurizatioproduct, countercurrent pressurized rinse(Reflux ratio=0.75).

���� �38� �6� 2000� 12�

Page 5: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

CO2 PSA���� ����� � 813

Ç. <=@ A� <=5 6 �� CO2� Ù� ��~Æ 0�. ��

CO2� �R� �J :Æ P Ctb. c� 6 �� <=0 CO2�

��* F*��4� 1� àá5 6 ��. U�Rº� k�� Rº%

. ¿�5 ��, ÒÒ Î Rº� ���� êy<=ï� ��� tu

� ±�0�. ��' �v� Fig. 3�� Ò U�Rº� ¦§ tuòª

� æ,�� 8 6 ��. Ý, 1�R�� 1.15�R, 1.3�R%. U�R

º� ÉI 7� tu� /�� ���Æ NJ��* êy<=ï� /

�* l� F*�� 1.5�R��� q�* �� NJ�� 1%. Í

K�. �6�� ��� å=*~. U�Rº� NJ� E¹ F*��

�v� ÍA��. Á� Ù� CMb� r»##� ��, Rº� ��

��� l� �� CO2* <=Ç. �RU�SG�� )L� CO2

� Ù� �POÆ 0�. ¦4� �6�� ¤?ç NJ�� �v� *

�ì� �6�.

�N�� U�Rº� F*#IW �3-%. tu� vN#³ 6 �

{� Ï 6 ���. Î� Î4�� ' *~ ��' pM� [N5 6

���; �� U�Rº� F*� ¦§ tuê*òª� �ó���. ß

ï� ��6ø q�* F*�� �N� lÿ-%. PSA �� Í

� �v��. �� <=SG�� <=� CO2� Ù� ßï� /�

7l� , 7 ��~� 7°��. <=SG��� <=0 CO2* J�

SG" �2 �� ��� P CMb. õ� 1�Ç. Á� <=#

æ ��� ��* �P ~ ë� �w A�� ßï� , ��* <=

0 CO2� Ù� F*#µ q�" XY ��� /�� '�. U�Rº

� 1.5�R� 7" lW, ßï� /� �w��� ßï� ¦§ q��

xH* �§ U�Rº��m ¼>' �v%. F*�� 1%. ÍK

% ßï� O~W� òª� l� *Ñ�Æ F*�� �v� lJ:

��. �� U�SG��� <=@� ��#æ� �o�� 1�4 C

Ò0�. �6�� ��, U�Rº� �� ��* P� Rº��l� Î

/�* F*�� �v� Í·� Ï 6 ��. �# Q�� U�Rº

� ��6ø ßï� ¦§ q�� /�� �PO �6�� /�� R

P � ±�" c� 6 ���. �� PSA" ¤ÌE� �P� �¢'

�l" � �� ±�.� <=@� S¶* ��~W ßï� ¦§ ^

-� U�¤¥� ±�0�� p���. U�Rº� F*� q� > �

6�� F*" �3�~Ñ U�Rº� F*56ø �¢ �N� ßï

F*� q�� vN� ¦§ �Tl� �6�� ���� ­�* X O

~� 7°� õ\d tu� �­�" *�õÆ 0�. ��� ��� �

� �9�dW J�U� 3D ��� ��� ±�5 6:� ��. Î

� ¶p" �� � � ñÆ �95 6 �{� Ï 6 ���.

4-3. ��� �� ��

Î1�W �U�� ��' U�Rº� T � ��� U�r»¼�

¦§ tuê*" #��$�. �� &' tuê*òª� Fig. 5� Í

A��. Î4�� l5� U�r»¼* F*56ø q�* G� NJ�

� �v%. T]<� Ï 6 ��. r»¼* 0.89 ��È~� r»¼

� F*� ¦4 q�� �Õ\ NJ� �% �6�� ��� ��

�{� 8 6 ��. ²' U�r»¼� ¦§ tu� xH ÀU� ßï

� �� N� ��' �v� *~ �{� 8 6 ��. �

U�r»¼* 0.85�N9 ��� ßï� F*� äG�� �� ��'

q�" ß~�J, q�� F*� ¼� �6�� ��* �ÕE� 8

6 ��.Î4�� r»¼ 0.85� 7l� 0.9� 7* q�� � 1% *

ï �� � ÍA �6�� Ò ßï� �P� 10% �N �Õ\

��E� 8 6 ��. l� )�-%. U�r»¼� ¦§ ¾v� Ï

�l� w�J q�m �6�� ÒÒ r»¼� &�� Í& Î4�

Fig. 6� 7��. U�r»¼* F*E� ¦4 z{�� ô��. q�*

Fig. 3. The effect of rinse pressure at PEV=0.1, R=0.75.

Fig. 4. Equilibrium adsorption isotherm of CO2, N2 and O2 on activatedcarbon at 25oC.

Fig. 5. The performance curve of the Case (5), PEV=0.1 atm, PRN=1.0 atm.

HWAHAK KONGHAK Vol. 38, No. 6, December, 2000

Page 6: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

814 ������������ � ���

NJ�� �v� l� , U�r»¼ 0.8-0.85 p��� �ó�* *Ñ

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ï� äG�� q�* ���Æ NJ<� Ï 6 ��. �6�� ��

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' ���� ?=Rº� 0.1�R, U�Rº� 1�R� 7 U�r»¼

" 0.8�N%. ¤Ì�� 1� �6� áW�� n��� Q5 6

��. �m Á� ±�� ßï� 10 SLPM�� U�#æ� YÁ� 190

Â.� U�r»¼" xH#³ ��, 0.8K_�� ��* �P��

�´'�. ¦4� U�r»¼ �# ^-�� oB�f, ��� �Z �

M¶p" ��J � �� ñÆ ̈ � 6 ��� 1� Ï 6 ���.

4-4. ��� ��� �� ��� �� �� ��

w�� ¿[�$5� U�Rº� r»¼� ¦4 � tu� ^-

�� oB�Æ 0�. Î1�W �U�� � e *~ ­�m ?=Rº

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'�. �" w�J &N ��� ¿�' ?= > U�Rº� ¦§

4*~ ��" �s' ±�" ÒÒ ¼Ó�$�; �" Fig. 8� ÍA

��. � 4*~ ��� �3-9 �v� q�� ��� U�r»¼�

F*� ¦4 G�-%. tu� F*�� ÀU" l9�� 1� �6

�� ��� ^-� U�r»¼* oB'�� 1��. Î4�� Ò ò

ª� 3 �� õ§ö��KL ßï� ÒÒ 7.6, 10, 15, 20 SLPM9 �

�" Í&�.

U�Rº� ?=Rº� xH� ¦§ 3 *~ ��� �P� (5)m (6)

� ��" ¼Ó�J ?=Rº� �' ¾v� Ï�lW, T SG��

?=Rº� P�~� ��, l� �� Ù� ?=P q�m �6��

�J :Æ 0�. ¦4� (6)� ��* (5)� ��l� ù� tu� l

9�. �mÁ� �v� Fig. 8� (c)m (d)��� å=*~. Í �;

e Î4 �# ?=Rº� P� �� ù� tu� l� ��.

� *h; ' *~ ��' �� ?=Rº� ��� U�Rº� F*

�� ��l� q�� X � ¾v� â�� p���. �#Q��, Fig.

8� lW (a)m (b) Î� (c)m (d)" ¼Ó5 7 (a)m (c), (b)m (d)�

��l� q�� NJ� l� �ÕE� 8 6 ��. �� ?=Rº�

PÀW ¼Ó- P� r»¼��� �� q�� Ctb� c� 6 �{

� lJ:� 1��. ��' p��, ?=Rº� PL �� ?=ï�

F*� ¦4 �� �6ï� RP Ç. Á� U�r»¼4� U�#

ßV� r»ï ��* RP Æ <%.F Í � �N%. 8 6

��.

3W U�Rº� F*�, ?=Rº� ��' ��m ¼Ó\� 7, w

m� 3&. q�� F*l� �6�� F** �U��� p�� Ï

6 ��. Á� ?=Rº ��� U�Rº� xH" ]^lW, Fig. 8�

(a)m (c), Î� (b)m (d)" ¼Ó�8 7, �6�� �Õ\ F*��

�N� 8 6 ��. ��, U�Rº� �J:W �3-%. �6��

F*'�� p�� lJ: ��. ��' �N� U� Rº� �J�

%.F <=� CO2� Ù� F*�Æ P ��#æ� _�~Ç.

�� �PE ±�. 8 6 ��. U�Rº� 1.5�R9 ��� �6�

� C�� Dô' "m Á� ^- � *~Æ �; Fig. 8� (c)m (d)

�� r»¼� F*� P` #�È~ �6�� F*" �3�Æ

<=@� ��� #�� �2�� a�� �6�� ÅP~� �N�

ÍAÆ 0�. Ý r»¼* P� ¾���� r»¼� F*� ¦4

��� ô,\ F*� �6�� *Ñ\ F*�� 1��. �7 ^&

� oB�f � ^& �2� r»¼��� q�� F*� �� �

P~ 3&. �6�� ô,' ��" ÍAÆ 0�. r»¼* P�

¾��� �6�� F*�� �ß� U�Rº� �� ��, U�#�

CO2 <=ï F*. cP~� �6�� F* ­�* r»¼� F*�

�' �6�� �' �� ­�l� � 7°%., U�#æ�� <=

@� *�\ ��� #�È~� q�� F*m E¹ �æ� �6�

F** Í � 1��[16].

²' U�Rº� �� ��* P� ��l� r»¼� F*� ¦§

q�� xH�� ßï� F*� ¦§ q�� xH�� /�~�

p�� Ï 6 ��. Ý, NR U���� ßï� xH� ¦§ q��

xH* b� òª� �ó�" ��� Ï 6 ��. Î� U�Rº�

1.5�R9 ��� òª� �ó�* *Ñ�� ßï� F*� ¦4 q�

� xHï� /�A� Ï 6 ��. ßï� ¦§ q�� NJ�� /�

~� �N� �� ¤Ì� �P�� U�Rº� ��� ���� �V

ßï� �J� ¤Ì�� 1� �6� W�� ß�' �vk� �´'

�. �" cX Ï�l� ñÆ ÍA� w�J ?=Rº� 0.05�R�

��,ßï� 7.6 SLPM9 ��m 20 SLPM9 ��" ¼Ó�J q�m

�6�� Fig. 9� ÍA��. Î4�� 8 6 �� "m Á� U�R

º� �� ���� r»¼� ¦§ �6�� ^&�� Í Æ �

; � �N� r»¼� �´ <=@�  H#IÆ P õ\d tu�

Fig. 6. The effect of reflux ratio on the purity in the Case (5), PEV=0.1 atm,PRN=1.0 atm.

Fig. 7. The effect of reflux ratio on the recovery in the Case (5), PEV=0.1 atm, PRN=1.0 atm.

���� �38� �6� 2000� 12�

Page 7: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

CO2 PSA���� ����� � 815

��" *�õÆ 0�. ��' �N� ßï� P� ��* � ��l

� ��\ Í �; ßï� /� ��* �6� W�� de ß�E

� Ï 6 ��.

C� Dô' "m Á� ?=Rº� ��m U�Rº� F*� �'

­�� b�-%. �. �§ ­�� ��� [C�Æ 0�. Ý, ��

� ?=ï� F*� �� U�# U�b� Ù� ���� C�� ­�

� 2�� <=ï� F*� �� U�#� <=ï� ���� C�

� ­���. ��' �ß* ?=Rº� ���$� 7l� U�Rº�

F*#I� ��* r»¼� F*� ¦§ q�� xHï� O~� !

9� � 1��.

±�-%., U�Rº� F* ?=Rº� �� ¶e r»¼" ��

#³ 6 �� ­�" *�õÆ �; q�W��� ?=Rº� PÀ

� 1�, 3&. �6� W��� U�Rº� ��� 1� l� ­�

-k� Ï 6 ���. �f-%. � e *~" ¶e -�5 6 ��

Fig. 8. Comparison of the performance curves at different rinse and evacuation conditions.(a) PEV=0.1 atm, PRN=1.0 atm; (b) PEV=0.05 atm, PRN=1.0 atm; (c) PEV=0.1 atm, PRN=1.5 atm; (d) PEV=0.05 atm, PRN=1.5 atm.�: reflux ratio=0.6;�:reflux ratio=0.65;�: reflux ratio=0.7;�: reflux ratio=0.75; �: reflux ratio=0.8; �: reflux ratio=0.85; �: reflux ratio=0.9.

Fig. 9. The effect of feed flow rate on the purity and recovery at PEV=0.05 atm.(a) feed flow rate: 7.6 SLPM; (b) feed flow rate: 20 SLPM

HWAHAK KONGHAK Vol. 38, No. 6, December, 2000

Page 8: CO PSA - CHERICCO2 PSA * †* * (2000 2 1 , 2000 9 18 ) Effect of Evacuation and Rinse Conditions on Performance in PSA Process for CO2 Recovery Hawung Lee, Jae-ho Choi*, Yeong-Koo

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se

p

ing

.:

W *é ù� ¤Ð� , Î� �7� �¤¥ r»¼" ��� 1

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6� ��� !�� ö� ªÞ�J ^- ¤¥� ª��ü 5 1��.

+ ()��� U� Rº� 1�R�� 1.5�R%. �J:�� 7m

?=Rº� 0.1�R�� 0.05�R%. PÀ�� 7, �o� NRU�S

G" �� c� 6 �| �6�l� ^& U ) �N� �6� NJ

� c� 6 ���;, � ���� r»¼� ¦§ ^-� �6�� o

B'�� p�� �95 6 ���. 6½-%. lW, 7.6 SLPM� ß

ï� �� NRU� > 0.1�R� ?=Rº�� 0.9� r»¼" ���

J c� 6 �� q�" c� w���, ?=Rº� 0.05�R%. P

ÀP :�� 7 r»¼" 0.8��. PL 6 �� ­�" c� 6 �

�%f �7� �6�� e )�� F*�$�. 3&. U�Rº� 1.5

�R%. ��� ��� r»¼" �# 0.8. PL 6 ��%f �7

� �6�� 2.5)* F*�$�. � e *~ ��" ¶e -�' �

�� r»¼" 0.75��. PL 6 �%f �6�� 3)È~ F*�$

�. + ()�� ��' S¶� é½" ��5 7, *é ù� ¤Ì ¤

¥� 0.05�R� ?=Rº� 1.5�R� U�Rº�� 0.75 ��� r»

¼" ���J P� ßï%. ¤Ì�� 1� ��-%. *é �6E

� �95 6 ���.

5. � �

`<=a9 CO2" Ctb. c� w' PSA ��� ^- ¤Ì¤

¥� ¨� w� �2ü �� 3D ��� ��, ¶p" �� ^-¤

¥� ¨� w' ¸-%., � tu� vN#I�; �6-9 SG9

U� > T SG� ¤¥� ¦§ ¾v� �s�$�. &N �� Zt

� <=�. ��', RºQ�Hm U�SG*  E0 qr �%.

F U�SG > T SG� ¤¥O� xH#µ*W� tu� xH"

¼Ó�$�. U�SG�� Rº� F*� U�#� <=ï� F*#µ

Ctb� �6�� F*#h�� p�� �95 6 ��%f �7 r

»¼� F*� ��� �È~ ô,' q�� NJ%. ÍK�. ?=

Rº� ��� ?=ï� F*#µ r»#� ßï� F*#I� ­�"

*�õf �� ô,' q�� vN%. ÍK�. ¦4� � e *~

��� ¶e U�SG� r»¼" �� 6 �� ­�. /��f �7

^-� tu� c� r»¼* oBE� �9�$�. ¦4� �" i

¤Ð�J <=@� ��� �A�� ¤Ì� ��PT�W *é ^-�

¤Ì¤¥� c� 6 �{� Ï 6 ���.

� �

+ ()��� 'j �º()!� ~! �k 6]�%f �� �p

lmW�.

����

bi : Langmuir parameter [atm−1]

Ci : gas concentration of component i [mol/cm3]

Ctotal : total gas phase concentration [mol/cm3]

Cps : heat capacity of adsorbent [J/g/K]

Cpg : specific heat of gas mixture [J/g/K]

∆Hi : heat of adsorption of component i [KJ/mol]

ki : overall mass transfer(LDF) rate coefficient of component i [s−1]

L : bed height [cm]

qi : amount adsorped of component i on the solid phase [mol/g

qi* : amount adsorped of component I in equilibrium with gas pha

[mol/g]

qm : langmuir parameter [mol/g]

t : time [s]

t1 : Langmuir parameter [mol/g]

t2 : Langmuir parameter [mol/g]

t3 : Langmuir parameter [atm−1]

t4 : Langmuir parameter [K]

T : temperature [K]

To : feed temperature [K]

u : interstitial gas velocity [cm/s]

ufeed : interstitial velocity of feed gas [cm/s]

uOR : interstitial velocity of rinse gas [cm/s]

yEQ,i : mole fraction of component i fed in pressurized equalization ste

yf, i : mole fraction of component i in gas mixture

yProduct,i: mole fraction of component i fed in rinse step

ρg : density of gas mixture [g/cm3]

ρbulk : bulk density [g/cm3]

ε : bed porosity [-]

����

1. Yang, R. T.: “Gas Separation by Adsorption Process,” Butterworths,

Boston(1987).

2. Ruthven, D. M., Frarooq, S. and Knaebel, K. S.: “Pressure Sw

Adsorption,” VCH, New York(1994).

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32, 2714(1993).

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HWAHAK KONGAK, 36, 562(1998).

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1017(1987).

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