���� JFIF  XX �� �� �     $.' ",#(7),01444'9=82<.342  2!!22222222222222222222222222222222222222222222222222�� ��" �� 4     ��   �� �,�PG"Z_�4�˷����kjز�Z�,F+��_z�,�© �����zh6�٨�ic�fu��� #ډb���_�N� ?� �wQ���5-�~�I���8��� �TK<5o�Iv-� ����k�_U_����� ~b�M��d��� �Ӝ�U�Hh��?]��E�w��Q���k�{��_}qFW7HTՑ��Y��F� ?_�'ϔ��_�Ջt� �=||I �� 6�έ"�����D���/[�k�9�� �Y�8 ds|\���Ҿp6�Ҵ���]��.����6� z<�v��@]�i% �� $j��~ �g��J>��no����pM[me�i$[�� �� s�o�ᘨ�˸ nɜG-�ĨU�ycP� 3.DB�li�;� �hj���x 7Z^�N�h��� ���N3u{�:j �x�힞��#M &��jL P@ _���� P�� &��o8 ������9 �����@Sz 6�t7#O�ߋ � s}Yf�T� ��lmr����Z)'N��k�۞p ����w\�T ȯ?�8` �O��i{wﭹW�[�r�� ��Q4F�׊�� �3m&L�=��h3� ���z~��#� \�l :�F,j@�� ʱ�wQT����8�"kJO��� 6�֚l���� }��� R�>ډK���]��y����&����p�}b�� ;N�1�m�r$� |��7�>e�@ B�TM*-i H��g�D�)� E�m�|�ؘbҗ�a ��Ҿ���� t4��� o���G��*oCN�rP���Q��@z,|?W[0 �����:�n,j WiE��W� �$~/�hp\��?��{(�0���+�Y8rΟ�+����>S-S�� ��VN;� }�s?.����� w �9��˟<���Mq4�Wv' ��{)0�1mB ��V����W[� ����8�/<� �%���wT^�5���b��)iM� p g�N�&ݝ� �VO~� q���u���9� ����!��J27��� �$ O-���! �: �%H��� ـ ����y�ΠM=t{!S�� oK8������ t<����è :a�� ����[���� �ա�H���~��w��Qz`�p o�^ �� ��Q��n�  �,uu�C� $ ^���,� �����8�#��:�6��e�|~� ��!�3� 3.�\0�� q��o�4`.|� ����y�Q�`~;�d�ׯ,��O�Zw�������`73�v�܋�< ���Ȏ�� ـ4k��5�K�a�u�=9Yd��$>x�A�&�� j0� ���vF��� Y� |�y��� ~�6�@c��1vOp �Ig�� ��4��l�OD� ��L����� R���c���j�_�uX 6��3?nk��Wy�f;^*B� ��@ �~a�`��Eu������ +� �� 6�L��.ü>��}y���}_�O�6�͐�:�Yr G�X��kG�� ���l^w�� �~㒶sy� �Iu�!� W ��X��N�7BV��O��!X�2����wvG�R�f�T#�����t�/?���%8�^�W�aT ��G�cL�M���I��(J����1~�8�?aT ���]����AS�E��(��*E}� 2�� #I/�׍qz��^t�̔��� b�Yz4x ���t�){ OH� �+(E��A&�N�������XT��o��"�XC�� '���)}�J�z�p� ��~5�}�^����+�6����w��c��Q�| Lp�d�H��}�(�.|����k��c4^� "�����Z?ȕ ��a< �L�!0 39C� �Eu� C�F�Ew�ç ;�n?�*o���B�8�bʝ���'#Rqf�� �M}7����]��� �s2tcS{�\icTx;�\��7K���P ���ʇ Z O-��~�� c>"��?�� �����P ��E��O�8��@�8��G��Q�g�a�Վ���󁶠 �䧘��_%#r�>� 1�z�a�� eb��qcP ѵ��n���#L��� =��׀t� L�7�` ��V��� A{�C:�g���e@ �w1 Xp 3�c3�ġ���� p��M"'-�@n4���fG� �B3�DJ�8[Jo�ߐ���gK)ƛ��$���� � ��8�3�����+���� �����6�ʻ���� ���S�kI�*KZlT _`�� �?��K� ���QK�d ����B`�s}�>���` ��*�>��,*@J�d�oF*� ���弝��O}�k��s��]��y�ߘ ��c1G�V���<=�7��7����6 �q�PT��tXԀ�!9*4�4Tހ 3XΛex�46�� �Y��D ����� �BdemDa����\�_l,� �G�/���֌7���Y�](�xTt^%�GE�����4�}bT ���ڹ�����; Y)���B�Q��u��>J/J � ⮶.�XԄ��j�ݳ� +E��d ��r�5�_D �1 �� o�� �B�x�΢�#� ��<��W�����8���R6�@ g�M�.��� dr�D��>(otU��@ x=��~v���2� ӣ�d�oBd ��3�eO�6�㣷�� ���ݜ 6��6Y��Qz`�� S��{���\P �~z m5{J/L��1������<�e�ͅPu� b�]�ϔ ���'�� ����f�b� Zpw��c`"��i���BD@:)ִ�:�]��h v�E� w���T�l ��P� ��"Ju�}��وV J��G6��. J/�Qgl߭�e�����@�z�Zev2u� )]կ��� ��7x�� �s�M�-<ɯ�c��r� v�����@��$�ޮ}lk���a�� �'����>x��O\�Z Fu>��� ��ck#��&:��`�$ �ai�>2Δ����l���oF[h� �lE�ܺ�Π k:)���` �� $[6�����9�����kOw�\|��� 8}������ބ:��񶐕� �I�A1/� =�2[�,�!��.}gN#�u����b ��� ~� �݊��}34q��� �d�E��L c��$ ��"�[q�U�硬g^��%B � z���r�p J�ru%v\h 1Y�ne` ǥ:g�� �pQM~�^� Xi� ��`S�:V2 9.�P���V� ?B�k�� AEvw%�_�9C�Q����wKekP ؠ�\� ;Io d�{ ߞo�c1eP��� �\� `����E=���@K<�Y�� �eڼ�J ���w����{av�F�'�M�@ /J��+9p ���|]���� �Iw &` ��8���& M�hg ��[�{ ��Xj�� %��Ӓ� $��(��� �ʹN��� <>�I���RY� ��K2�NPlL�ɀ )��&e� ���B+ь����( � �JTx ���_?EZ� }@ 6�U���뙢ط�z��dWI� n` D����噥�[��uV��"�G& Ú����2 g�}&m� �?ċ �"����Om#� ������� � ��{� ON��"S�X ��Ne��ysQ���@ Fn��Vg��� dX�~nj� ]J�<�K]: ��FW�� b�������62 �=��5f����JKw� �bf�X� 55��~J �%^� ���:�-�QIE��P��v�nZum� z � ~ə ���� ���ة����;�f��\v��� g�8�1��f2 4;�V���ǔ�)��� �9���1\�� c��v�/'Ƞ�w����� ��$�4�R-��t�� �� e�6�/�ġ �̕Ecy�J���u�B���<�W�ַ~�w[B1L۲�-JS΂�{���΃���� ��A��20�c# �� @    0!1@AP"#2Q`$3V�%45a6�FRUq���   � ���^7ׅ,$n� ������+��F�`��2X'��0vM��p�L=������ 5��8������u�p~���.�`r�����\��� O��,ư�0oS ��_�M�����l���4�kv\JSd���x���SW�<��Ae�IX����������$I���w�:S���y���›R��9�Q[���,�5�;�@]�%���u�@ *ro�lbI �� ��+���%m:�͇ZV�����u�̉����θau<�fc�.����{�4Ա� �Q����*�Sm��8\ujqs]{kN���)qO�y�_*dJ�b�7���yQqI&9�ԌK!�M}�R�;�� ����S�T���1���i[U�ɵz�]��U)V�S6���3$K{� ߊ<�(� E]Զ[ǼENg�����'�\?#)Dkf��J���o��v���'�%ƞ�&K�u� !��b�35LX�Ϸ��63$K�a�;�9>,R��W��3�3� d�JeTYE.Mϧ��-�o�j3+y��y^�c�������VO�9NV\nd�1 ��!͕_)a�v;����թ�M�lWR1��)El��P;��yوÏ�u 3�k�5Pr6<�⒲l�!˞*��u־�n�!�l:����UNW ��%��Chx8vL'��X�@��*��)���̮��ˍ��� � ��D-M�+J�U�kvK����+�x8��cY������?�Ԡ��~3mo��|�u@[XeY�C�\Kp�x8�oC�C�&����N�~3-H���� ��MX�s�u<`���~"WL��$8ξ��3���a�)|:@�m�\���^�`�@ҷ)�5p+��6���p�%i)P M���ngc�����#0Aruz���RL+xSS?���ʮ}()#�t��mˇ!��0}}y����<�e� �-ή�Ԩ��X������ MF���ԙ~l L.3���}�V뽺�v��� ��멬��Nl�)�2����^�Iq��a��M��qG��T�����c3#������3U�Ǎ���}��לS�|qa��ڃ�+���-��2�f����/��bz��ڐ�� �ݼ[2�ç����k�X�2�* �Z�d���J�G����M*9W���s{��w���T��x��y,�in�O�v��]���n����P�$� JB@=4�OTI�n��e�22a\����q�d���%�$��(���:���: /*�K[PR�fr\nڙdN���F�n�$�4� [�� U�zƶ����� �mʋ���,�ao�u 3�z� �x��Kn����\[��VFmbE;�_U��&V�Gg�]L�۪&#n%�$ɯ� dG���D�TI=�%+AB�Ru#��b4�1�»x�cs�YzڙJG��f��Il� �d�eF'T� iA��T���uC�$����Y��H?����[!G`}���ͪ� �纤Hv\������j�Ex�K���!���OiƸ�Yj�+u-<���'q����uN�*�r\��+�]���<�wOZ.fp�ێ��,-*)V?j-kÊ#�`�r��dV����(�ݽBk�����G�ƛk�QmUڗe��Z���f}|����8�8��a���i��3'J�����~G_�^���d�8w������ R�`(�~�.��u���l�s+g�bv���W���lGc}��u���afE~1�Ue������Z�0�8�=e�� f@/�jqEKQQ�J� �oN��J���W5~M>$6�Lt�;$ʳ{���^��6�{����v6���ķܰg�V�cnn �~z�x�«�,2�u�?cE+Ș�H؎�%�Za�)���X>uW�Tz�Nyo����s���FQƤ��$��*�&�LLXL)�1�" L��eO��ɟ�9=���:t��Z���c��Ž���Y?�ӭV�wv�~,Y��r�ۗ�|�y��GaF�����C�����.�+� ���v1���fήJ�����]�S��T��B��n5sW}y�$��~z�'�c ��8 ��� ,! �p��VN�S��N�N�q��y8z˱�A��4��*��'������2n<�s���^ǧ˭P�Jޮɏ�U�G�L�J�*#��<�V��t7�8����TĜ>��i}K%,���)[��z�21z ?�N�i�n1?T�I�R#��m-�����������������1����lA�`��fT5+��ܐ�c�q՝��ʐ��,���3�f2U�եmab��#ŠdQ�y>\��)�SLY����w#��.���ʑ�f��� ,"+�w�~�N�'�c�O�3F�������N<���)j��&��,-� �љ���֊�_�zS���TǦ����w�>��?�������n��U仆�V���e�����0���$�C�d���rP �m�׈e�Xm�Vu� �L��.�bֹ��� �[Դaզ���*��\y�8�Է:�Ez\�0�Kq�C b��̘��cө���Q��=0Y��s�N��S.��� 3.���O�o:���#���v7�[#߫ ��5�܎�L���Er4���9n��COWlG�^��0k�%<���ZB���aB_���������'=��{i�v�l�$�uC���mƎҝ{�c㱼�y]���W�i ��ߧc��m�H� m�"�"�����;Y�ߝ�Z�Ǔ�����:S#��|}�y�,/k�Ld� TA�(�AI$+I3��;Y*���Z��}|��ӧO��d�v��..#:n��f>�>���ȶI�TX��� 8��y����"d�R�|�)0���=���n4��6ⲑ�+��r<�O�܂~zh�z����7ܓ�HH�Ga롏���nCo�>������a ���~]���R���̲c?�6(�q�;5%� |�uj�~z8R =X��I�V=�|{v�Gj\gc��q����z�؋%M�ߍ����1y��#��@f^���^�>N��� ��#x#۹��6�Y~�?�dfPO��{��P�4��V��u1E1J �*|���%�� �JN��`eWu�zk M6���q t[�� ��g�G���v��WIG��u_ft����5�j�"�Y�:T��ɐ���*�;� e5���4����q$C��2d�}���� _S�L#m�Yp��O�.�C�;��c����Hi#֩%+) �Ӎ��ƲV���SYź��g |���tj��3�8���r|���V��1#;.SQ�A[���S������#���`n�+���$��$ I �P\[�@�s��(�ED�z���P��])8�G#��0B��[ى��X�II�q<��9�~[Z멜�Z�⊔IWU&A>�P~�#��dp<�?����7���c��'~���5 ��+$���lx@�M�dm��n<=e�dyX��?{�|Aef ,|n3�<~z�ƃ�uۧ�����P��Y,�ӥQ�*g�#먙R�\���;T��i,��[9Qi歉����c>]9�� ��"�c��P�� �Md?٥��If�ت�u��k��/����F��9�c*9��Ǎ:�ØF���z�n*�@|I�ށ9����N3{'��[�'ͬ�Ҳ4��#}��!�V� Fu��,�,mTIk���v C�7v���B�6k�T9��1�*l� '~��ƞF��lU��'�M ����][ΩũJ_�{�i�I�n��$�� �L�� j��O�dx�����kza۪��#�E��Cl����x˘�o�����V���ɞ�ljr��)�/,�߬h�L��#��^��L�ф�,íMƁe�̩�NB�L�����iL����q�}��(��q��6IçJ$�W�E$��:������=#����(�K�B����zђ <��K(�N�۫K�w��^O{!����) �H���>x�������lx�?>Պ�+�>�W���,Ly!_�D���Ō�l���Q�!�[ �S����J��1��Ɛ�Y}��b,+�Lo�x�ɓ)����=�y�oh�@�꥟/��I��ѭ=��P�y9��� �ۍYӘ�e+�p�Jnϱ?V\SO%�(�t� ���=?MR�[Ș�����d�/ ��n�l��B�7j� ��!�;ӥ�/�[-���A�>� dN�sLj ��,ɪv��=1c�.SQ�O3�U���ƀ�ܽ�E����������̻��9G�ϷD�7(�}��Ävӌ\� y�_0[w ���<΍>����a_��[0+�L��F.�޺��f�>oN�T����q;���y\��bՃ��y�jH�<|q-eɏ�_?_9+P���Hp$�����[ux�K w�Mw��N�ی'$Y2�=��q���KB��P��~�� ����Yul:�[<����F1�2�O���5=d����]Y�sw:���Ϯ���E��j,_Q��X��z`H1,#II ��d�wr��P˂@�ZJV����y$�\y�{}��^~���[:N����ߌ�U�������O��d�����ؾe��${p>G��3c���Ė�lʌ�� ת��[��`ϱ�-W����dg�I��ig2��� ��}s ��ؤ(%#sS@���~���3�X�nRG�~\jc3�v��ӍL��M[JB�T��s3}��j�Nʖ��W����;7� �ç?=X�F=-�=����q�ߚ���#���='�c��7���ڑW�I(O+=:uxq�������������e2�zi+�kuG�R��������0�&e�n���iT^J����~\jy���p'dtG��s����O��3����9* �b#Ɋ�� p������[Bws�T�>d4�ۧs���nv�n���U���_�~,�v����ƜJ1��s�� �QIz�� )�(lv8M���U=�;����56��G���s#�K���MP�=��LvyGd��}�VwWBF�'�à �?MH�U�g2�� ����!�p�7Q��j��ڴ����=��j�u��� Jn�A s���uM������e��Ɔ�Ҕ�!) '��8Ϣ�ٔ� �ޝ(��Vp���צ֖d=�IC�J�Ǡ{q������kԭ�߸���i��@K����u�|�p=..�*+����x�����z[Aqġ#s2a�Ɗ���RR�)*HRsi�~�a &f��M��P����-K�L@��Z��Xy�'x�{}��Zm+���:�)�) IJ�-i�u���� ���ܒH��'� L(7�y�GӜq���� j��� 6ߌg1�g�o���,kر���tY�?W,���p���e���f�OQS��!K�۟cҒA�|ս�j�>��=⬒��˧L[�� �߿2JaB~R��u�:��Q�] �0H~���]�7��Ƽ�I���( }��cq '�ήET���q�?f�ab���ӥvr� �)o��-Q��_'����ᴎo��K������;��V���o��%���~OK ����*��b�f:���-ťIR��`B�5!RB@���ï�� �u �̯e\�_U�_������� g�ES��3������� QT��a�� ��x����U<~�c?�*�#]�MW,[8O�a�x��]�1bC|踤�P��lw5V%�)�{t�<��d��5���0i�XSU��m:��Z�┵�i�"��1�^B�-��P�hJ��&)O��*�D��c�W��vM��)����}���P��ܗ-q����\mmζZ-l@�}��a��E�6��F�@��&Sg@���ݚ�M����� ȹ 4����#p�\H����dYDo�H���"��\��..R�B�H�z_�/5˘����6��KhJR��P�mƶi�m���3� ,#c�co��q�a)*P t����R�m�k�7x�D�E�\Y�閣_X�<���~�)���c[[�BP����6�Yq���S��0����%_����;��Àv�~�| VS؇ ��'O0��F0��\���U�-�d@�����7�SJ*z��3n��y��P����O��������� m�~�P�3|Y��ʉr#�C�<�G~�.,! ���bqx���h~0=��!ǫ�jy����l� O,�[B��~��|9��ٱ����Xly�#�i�B��g%�S��������tˋ���e���ې��\[d�t)��.+u�|1 ������#�~Oj����hS�%��i.�~X���I�H�m��0n���c�1uE�q��cF�RF�o���7� �O�ꮧ� ���ۛ{��ʛi5�rw?׌#Qn�TW��~?y$��m\�\o����%W� ?=>S�N@�� �Ʈ���R����N�)�r"C�:��:����� �����#��qb��Y�. �6[��2K����2u�Ǧ�HYR��Q�MV��� �G�$��Q+.>�����nNH��q�^��� ����q��mM��V��D�+�-�#*�U�̒ ���p욳��u:�������IB���m� ��PV@O���r[b= �� ��1U�E��_Nm�yKbN�O���U�}�the�`�|6֮P>�\2�P�V���I�D�i�P�O;�9�r�mAHG�W�S]��J*�_�G��+kP�2����Ka�Z���H�'K�x�W�MZ%�O�YD�Rc+o��?�q��Ghm��d�S�oh�\�D�|:W������UA�Qc yT�q� �����~^�H��/��#p�CZ���T�I�1�ӏT����4��"�ČZ�����}��`w�#�*,ʹ�� ��0�i��課�Om�*�da��^gJ݅{���l�e9uF#T�ֲ��̲�ٞC"�q���ߍ ոޑ�o#�XZTp����@ o�8��(jd��xw�]�,f���`~� |,s��^����f�1���t��|��m�򸄭/ctr��5s��7�9Q�4�H1꠲BB@ l9@���C�����+�wp�xu�£Yc�9��?`@#�o�mH�s2��)�=��2�.�l����jg�9$�Y�S�%*L������R�Y������7Z���,*=�䷘$�������arm�o�ϰ���UW.|�r�uf����IGw�t����Zwo��~5 ��YյhO+=8fF�)�W�7�L9lM�̘·Y���֘YLf�큹�pRF���99.A �"wz��=E\Z���'a� 2��Ǚ�#;�'}�G���*��l��^"q��+2FQ� hj��kŦ��${���ޮ-�T�٭cf�|�3#~�RJ����t��$b�(R��(����r���dx� >U b�&9,>���%E\� Ά�e�$��'�q't��*�א���ެ�b��-|d���SB�O�O��$�R+�H�)�܎�K��1m`;�J�2�Y~9��O�g8=vqD`K[�F)k�[���1m޼c��n���]s�k�z$@��)!I �x՝"v��9=�ZA=`Ɠi �:�E��)` 7��vI��}d�YI�_ �o�:ob���o ���3Q��&D&�2=�� �Ά��;>�h����y.*ⅥS������Ӭ�+q&����j|UƧ��� �}���J0��WW< ۋS�)jQR�j���Ư��rN)�Gű�4Ѷ(�S)Ǣ�8��i��W52���No˓� ۍ%�5brOn�L�;�n��\G����=�^U�dI���8$�&���h��'���+�(������cȁ߫k�l��S^���cƗjԌE�ꭔ��gF���Ȓ��@���}O���*;e�v�WV���YJ\�]X'5��ղ�k�F��b 6R�o՜m��i N�i���� >J����?��lPm�U��}>_Z&�KK��q�r��I�D�Չ~�q�3fL�:S�e>���E���-G���{L�6p�e,8��������QI��h��a�Xa��U�A'���ʂ���s�+טIjP�-��y�8ۈZ?J$��W�P� ��R�s�]��|�l(�ԓ��sƊi��o(��S0 ��Y� 8�T97.�����WiL��c�~�dxc�E|�2!�X�K�Ƙਫ਼�$((�6�~|d9u+�qd�^3�89��Y�6L�.I�����?���iI�q���9�)O/뚅����O���X��X�V��ZF[�یgQ�L��K1���RҖr@v�#��X�l��F���Нy�S�8�7�kF!A��sM���^rkp�jP�DyS$N���q�� nxҍ!U�f�!eh�i�2�m ���`�Y�I�9r�6� �TF���C}/�y�^���Η���5d�'��9A-��J��>{�_l+�`��A���[�'��յ�ϛ#w:݅�%��X�}�&�PSt�Q�"�-��\縵�/����$Ɨh�Xb�*�y��BS����;W�ջ_mc�����vt?2}1�;qS�d�d~u:2k5�2�R�~�z+|HE!)�Ǟl��7`��0�<�,�2*���Hl-��x�^����'_TV�gZA�'j� ^�2Ϊ��N7t�����?w�� �x1��f��Iz�C-Ȗ��K�^q�;���-W�DvT�7��8�Z�������� hK�(P:��Q- �8�n�Z���܃e貾�<�1�YT<�,�����"�6{ / �?�͟��|1�:�#g��W�>$����d��J��d�B�� =��jf[��%rE^��il:��B���x���Sּ�1հ��,�=��*�7 fcG��#q� �eh?��2�7�����,�!7x��6�n�LC�4x��},Geǝ�tC.��vS �F�43��zz\��;QYC,6����~;RYS/6���|2���5���v��T��i����������mlv��������&� �nRh^ejR�LG�f���? �ۉҬܦƩ��|��Ȱ����>3����!v��i�ʯ�>�v��オ�X3e���_1z�Kȗ\<������!�8���V��]��?b�k41�Re��T�q��mz��TiOʦ�Z��Xq���L������q"+���2ۨ��8}�&N7XU7Ap�d�X��~�׿��&4e�o�F��� �H�� ��O���č�c�� 懴�6���͉��+)��v;j��ݷ�� �UV�� i��� j���Y9GdÒJ1��詞�����V?h��l�� ��l�cGs�ځ�������y�Ac���� �\V3�? �� ܙg�>qH�S,�E�W�[�㺨�uch�⍸�O�}���a��>�q�6�n6� ���N6�q�� ���� N    ! 1AQaq�0@����"2BRb�#Pr���3C`��Scst���$4D���%Td��  ? � ��N����a��3��m���C���w��������xA�m�q�m��� m������$����4n淿t'��C"w��zU=D�\R+w�p+Y�T�&�պ@��ƃ��3ޯ?�Aﶂ��aŘ���@-�����Q�=���9D��ռ�ѻ@��M�V��P��܅�G5�f�Y<�u=,EC)�<�Fy'�"�&�չ�X~f��l�KԆV��?�� �W�N����=(� �;���{�r����ٌ�Y���h{�١������jW����P���Tc�����X�K�r��}���w�R��%��?���E��m�� �Y�q|����\lEE4� ��r���}�lsI�Y������f�$�=�d�yO����p�����yBj8jU�o�/�S��?�U��*������ˍ�0����� �u�q�m [�?f����a�� )Q�>����6#������� ?����0UQ����,IX���(6ڵ[�DI�MNލ�c&���υ�j\��X�R|,4��� j������T�hA�e��^���d���b<����n�� �즇�=!���3�^�`j�h�ȓr��jẕ�c�,ٞX����-����a�ﶔ���#�$��]w�O��Ӫ�1y%��L�Y<�wg#�ǝ�̗`�x�xa�t�w��»1���o7o5��>�m뭛C���Uƃߜ}�C���y1Xνm�F8�jI���]����H���ۺиE@I�i;r�8ӭ���� V�F�Շ| ��&?�3|x�B�MuS�Ge�=Ӕ�#BE5G�� ���Y!z��_e��q�р/W>|-�Ci߇�t�1ޯќd�R3�u��g�=0 5��[?�#͏��q�cf���H��{ ?u�=?�?ǯ���}Z��z���hmΔ�BFTW�����<�q� (v� ��!��z���iW]*�J�V�z��gX֧A�q�&��/w���u�gYӘa���; �i=����g:��?2�dž6�ى�k�4�>�Pxs����}������G�9� �3 ���)gG�R<>r h�$��'nc�h�P��Bj��J�ҧH� -��N1���N��?��~��}-q!=��_2hc�M��l�vY%UE�@|�v����M2�.Y[|y�"Eï��K�ZF,�ɯ?,q�?v�M 80jx�"�;�9vk�����+ ֧�� �ȺU��?�%�vcV��mA�6��Qg^M��� �A}�3�nl� QRN�l8�kkn�'�����(��M�7m9و�q���%ޟ���*h$Zk"��$�9��: �?U8�Sl��,,|ɒ��xH(ѷ����Gn�/Q�4�P��G�%��Ա8�N��!� �&�7�;���eKM7�4��9R/%����l�c>�x;������>��C�:�����t��h?aKX�bhe�ᜋ^�$�Iհ �hr7%F$�E��Fd���t��5���+�(M6�t����Ü�UU|zW�=a�Ts�Tg������dqP�Q����b'�m���1{|Y����X�N��b �P~��F^F:����k6�"�j!�� �I�r�`��1&�-$�Bevk:y���#y w��I0��x��=D�4��tU���P�ZH��ڠ底taP��6����b>�xa� ���Q�#� WeF��ŮNj�p�J* mQ�N��� �*I�-*�ȩ�F�g�3 �5��V�ʊ�ɮ�a��5F���O@{���NX��?����H�]3��1�Ri_u��������ѕ�� ����0��� F��~��:60�p�͈�S��qX#a�5>���`�o&+�<2�D����: �������ڝ�$�nP���*)�N�|y�Ej�F�5ټ�e���ihy�Z �>���k�bH�a�v��h�-#���!�Po=@k̆IEN��@��}Ll?j�O������߭�ʞ���Q|A07x���wt!xf���I2?Z��<ץ�T���cU�j��]�� 陎Ltl �}5�ϓ��$�,��O�mˊ�;�@O��jE��j(�ا,��LX���LO���Ц�90�O �.����a��nA���7������j4 ��W��_ٓ���zW�jcB������y՗+EM�)d���N�g6�y1_x��p�$Lv :��9�"z��p���ʙ$��^��JԼ*�ϭ����o���=x�Lj�6�J��u82�A�H�3$�ٕ@�=Vv�]�'�qEz�;I˼��)��=��ɯ���x �/�W(V���p�����$ �m�������u�����񶤑Oqˎ�T����r��㠚x�sr�GC��byp�G��1ߠ�w e�8�$⿄����/�M{*}��W�]˷.�CK\�ުx���/$�WP w���r� |i���&�}�{�X� �>��$-��l���?-z���g����lΆ���(F���h�vS*���b���߲ڡn,|)mrH[���a�3�ר�[1��3o_�U�3�TC�$��(�=�)0�kgP���� ��u�^=��4 �WYCҸ:��vQ�ר�X�à��tk�m,�t*��^�,�}D*� �"(�I��9R����>`�`��[~Q]�#af��i6l��8���6�:,s�s�N6�j"�A4���IuQ��6E,�GnH��zS�HO�uk�5$�I�4��ؤ�Q9�@��C����wp �BGv[]�u�Ov��� 0I4���\��y�����Q�Ѹ��~>Z��8�T��a��q�ޣ;z��a���/��S��I:�ܫ_�|������>=Z����8:�S��U�I�J��"IY���8%b8���H��:�QO�6�;7�I�S��J��ҌAά3��>c���E+&jf$eC+�z�;��V����� �r���ʺ������my�e���aQ�f&��6�ND ��.:��NT�vm�<- u���ǝ\MvZY�N�NT��-A�>jr!S��n�O 1�3�Ns�%�3D@���`������ܟ 1�^c<���� �a�ɽ�̲�Xë#�w�|y�cW�=�9I*H8�p�^(4���՗�k��arOcW�tO�\�ƍR��8����'�K���I�Q�����?5�>[�}��yU�ײ -h��=��% q�ThG�2�)���"ו3]�!kB��*p�FDl�A���,�eEi�H�f�Ps�����5�H:�Փ~�H�0Dت�D�I����h�F3�������c��2���E��9�H��5�zԑ�ʚ�i�X�=:m�xg�hd(�v����׊�9iS��O��d@0ڽ���:�p�5�h-��t�&���X�q�ӕ,��ie�|���7A�2���O%P��E��htj��Y1��w�Ѓ!����  ���� ࢽ��My�7�\�a�@�ţ�J �4�Ȼ�F�@o�̒?4�wx��)��]�P��~�����u�����5�����7X ��9��^ܩ�U;Iꭆ 5 �������eK2�7(�{|��Y׎ �V��\"���Z�1� Z�����}��(�Ǝ"�1S���_�vE30>���p;� ΝD��%x�W�?W?v����o�^V�i�d��r[��/&>�~`�9Wh��y�;���R�� � ;;ɮT��?����r$�g1�K����A��C��c��K��l:�'��3 c�ﳯ*"t8�~l��)���m��+U,z��`( �>yJ�?����h>��]��v��ЍG*�{`��;y]��I�T� ;c��NU�fo¾h���/$���|NS���1�S�"�H��V���T���4��uhǜ�]�v;���5�͠x��'C\�SBpl���h}�N����� A�Bx���%��ޭ�l��/����T��w�ʽ]D�=����K���ž�r㻠l4�S�O?=�k �M:� ��c�C�a�#ha���)�ѐxc�s���gP�iG�� {+���x���Q���I= �� z��ԫ+ �8"�k�ñ�j=|����c ��y��CF��/ ��*9ж�h{ �?4�o� ��k�m�Q�N�x��;�Y��4膚�a�w?�6�> e]�����Q�r�:����g�,i"�����ԩA� *M�<�G��b�if��l^M��5� �Ҩ�{����6J��ZJ�����P�*�����Y���ݛu�_4�9�I8�7���������,^ToR���m4�H��?�N�S�ѕw��/S��甍�@�9H�S�T��t�ƻ���ʒU��*{Xs�@����f��� ��֒Li�K{H�w^���������Ϥm�tq���s� ���ք��f:��o~s��g�r��ט� �S�ѱC�e]�x���a��) ���(b-$(�j>�7q�B?ӕ�F��hV25r[7 Y� }L�R��}����*sg+��x�r�2�U=�*'WS��ZDW]�WǞ�<��叓���{�$�9Ou4��y�90-�1�'*D`�c�^o?(�9��u���ݐ��'PI&� f�Jݮ�������:wS����jfP1F:X �H�9dԯ�� �˝[�_54 �}*;@�ܨ�� ð�yn�T���?�ןd�#���4rG�ͨ��H�1�|-#���Mr�S3��G�3�����)�.᧏3v�z֑��r����$G"�`j �1t��x0<Ɔ�Wh6�y�6��,œ�Ga��gA����y��b��)� �h�D��ß�_�m��ü �gG;��e�v��ݝ�nQ� ��C����-�*��o���y�a��M��I�>�<���]obD��"�:���G�A��-\%LT�8���c�)��+y76���o�Q�#*{�(F�⽕�y����=���rW�\p���۩�c���A���^e6��K������ʐ�cVf5$�'->���ՉN"���F�"�UQ@�f��Gb~��#�&�M=��8�ט�JNu9��D��[̤�s�o�~��� ��� G��9T�tW^g5y$b��Y'��س�Ǵ�=��U-2 #�MC�t(�i� �lj�@Q 5�̣i�*�O����s�x�K�f��}\��M{E�V�{�υ��Ƈ�����);�H����I��fe�Lȣr�2��>��W� I�Ȃ6������i��k�� �5�YOxȺ����>��Y�f5'��|��H+��98pj�n�.O�y�������jY��~��i�w'������l�;�s�2��Y��:'lg�ꥴ)o#'Sa�a�K��Z� �m��}�`169�n���"���x��I ��*+� }F<��cГ���F�P�������ֹ*�PqX�x۩��,� ��N�� �4<-����%����:��7����W���u�`����� $�?�I��&����o��o��`v�>��P��"��l���4��5'�Z�gE���8���?��[�X�7(��.Q�-��*���ތL@̲����v��.5���[��=�t\+�CNܛ��,g�SQnH����}*F�G16���&:�t��4ُ"A��̣��$�b �|����#rs��a�����T�� ]�<�j��B S�('$�ɻ� �wP;�/�n��?�ݜ��x�F��yUn�~mL*-�������Xf�wd^�a�}��f�,=t�׵i�.2/wpN�Ep8�OР���•��R�FJ� 55TZ��T �ɭ�<��]��/�0�r�@�f��V��V����Nz�G��^���7hZi����k��3�,kN�e|�vg�1{9]_i��X5y7� 8e]�U����'�-2,���e"����]ot�I��Y_��n�(JҼ��1�O ]bXc���Nu�No��pS���Q_���_�?i�~�x h5d'�(qw52] ��'ޤ�q��o1�R!���`ywy�A4u���h<קy���\[~�4�\ X�Wt/� 6�����n�F�a8��f���z �3$�t(���q��q�x��^�XWeN'p<-v�!�{�(>ӽDP7��ո0�y)�e$ٕv�Ih'Q�EA�m*�H��RI��=:��� ���4牢) �%_iN�ݧ�l]� �Nt���G��H�L��� ɱ�g<���1V�,�J~�ٹ�"K��Q�� 9�HS�9�?@��k����r�;we݁�]I�!{ �@�G�[�"��`���J:�n]�{�cA�E����V��ʆ���#��U9�6����j�#Y�m\��q�e4h�B�7��C�������d<�?J����1g:ٳ���=Y���D�p�ц� ׈ǔ��1�]26؜oS�'��9�V�FVu�P�h�9�xc�oq�X��p�o�5��Ա5$�9W�V(�[Ak�aY錎qf;�'�[�|���b�6�Ck��)��#a#a˙��8���=äh�4��2��C��4tm^ �n'c� ��]GQ$[Wҿ��i���vN�{Fu ��1�gx��1┷���N�m��{j-,��x�� Ūm�ЧS�[�s���Gna���䑴�� x�p 8<������97�Q���ϴ�v�aϚG��Rt�Һ׈�f^\r��WH�JU�7Z���y)�vg=����n��4�_)y��D'y�6�]�c�5̪ �\� �PF�k����&�c;��cq�$~T�7j ���nç]�<�g ":�to�t}�159�<�/�8������m�b�K#g'I'.W����� 6��I/��>v��\�MN��g���m�A�yQL�4u�Lj�j9��#44�t��l^�}L����n��R��!��t��±]��r��h6ٍ>�yҏ�N��fU�� ���� Fm@�8}�/u��jb9������he:A�y�ծw��GpΧh�5����l}�3p468��)U��d��c����;Us/�֔�YX�1�O2��uq�s��`hwg�r~�{ R��mhN��؎*q 42�*th��>�#���E����#��Hv�O����q�}����� 6�e��\�,Wk�#���X��b>��p}�դ��3���T5��†��6��[��@ �P�y*n��|'f�֧>�lư΂�̺����SU�'*�q�p�_S�����M�� '��c�6��� ��m�� ySʨ;M��r���Ƌ�m�Kxo,���Gm�P��A�G�:��i��w�9�}M(�^�V��$ǒ�ѽ�9���|���� �a����J�SQ�a���r�B;����}���ٻ֢�2�%U���c�#�g���N�a�ݕ�'�v�[�OY'��3L�3�;,p�]@�S��{ls��X�'���c�jw� k'a�.��}�}&�� �dP�*�bK=ɍ!����;3n�gΊU�ߴmt�'*{,=SzfD� A��ko~�G�aoq�_mi}#�m�������P�Xhύ��� �mxǍ�΂���巿zf��Q���c���|kc�����?���W��Y�$���_Lv����l߶��c���`?����l�j�ݲˏ!V��6����U�Ђ(A���4y)H���p�Z_�x��>���e�� R��$�/�`^'3qˏ�-&Q�=?��CFVR �D�fV�9��{�8g�������n�h�(P"��6�[�D���< E�����~0<@�`�G�6����Hг�cc�� �c�K.5��D��d�B���`?�XQ��2��ٿyqo&+�1^� DW�0�ꊩ���G�#��Q�nL3��c���������/��x ��1�1 [y�x�პCW��C�c�UĨ80�m�e�4.{�m��u���I=��f�����0QRls9���f���������9���~f�����Ǩ��a�"@�8���ȁ�Q����#c�ic������G��$���G���r/$W�(��W���V�"��m�7�[m�A�m����bo��D� j����۳� l���^�k�h׽����� ��#� iXn�v��eT�k�a�^Y�4�BN�� ĕ�� 0    !01@Q"2AaPq3BR������ ? � ��@4�Q�����T3,���㺠�W�[=JK�Ϟ���2�r^7��vc�:�9 �E�ߴ�w�S#d���Ix��u��:��Hp��9E!�� V 2;73|F��9Y���*ʬ�F��D����u&���y؟��^EA��A��(ɩ���^��GV:ݜDy�`��Jr29ܾ�㝉��[���E;Fzx��YG��U�e�Y�C���� ����v-tx����I�sם�Ę�q��Eb�+P\ :>�i�C'�;�����k|z�رn�y]�#ǿb��Q��������w�����(�r|ӹs��[�D��2v-%��@;�8<a���[\o[ϧw��I!��*0�krs)�[�J9^��ʜ��p1)� "��/_>��o��<1����A�E�y^�C��`�x1'ܣn�p��s`l���fQ��):�l����b>�Me�jH^?�kl3(�z:���1ŠK&?Q�~�{�ٺ�h�y���/�[��V�|6��}�KbX����mn[-��7�5q�94�������dm���c^���h� X��5��<�eޘ>G���-�}�دB�ޟ� ��|�rt�M��V+�]�c?�-#ڛ��^ǂ}���Lkr���O��u�>�-D�ry� D?:ޞ�U��ǜ�7�V��?瓮�"�#���r��չģVR;�n���/_� ؉v�ݶe5d�b9��/O��009�G���5n�W����JpA�*�r9�>�1��.[t���s�F���nQ� V 77R�]�ɫ8����_0<՜�IF�u(v��4��F�k�3��E)��N:��yڮe��P�`�1}�$WS��J�SQ�N�j �ٺ��޵�#l���ј(�5=��5�lǏmoW�v-�1����v,W�mn��߀$x�<����v�j(����c]��@#��1������Ǔ���o'��u+����;G�#�޸��v-lη��/(`i⣍Pm^� ��ԯ̾9Z��F��������n��1��� ��]�[��)�'������ :�֪�W��FC����� �B9،!?���]��V��A�Վ�M��b�w��G F>_DȬ0¤�#�QR�[V��kz���m�w�"��9ZG�7'[��=�Q����j8R?�zf�\a�=��O�U����*oB�A�|G���2�54 �p��.w7� �� ��&������ξxGHp� B%��$g�����t�Џ򤵍z���HN�u�Я�-�'4��0�� ;_�� 3     !01"@AQa2Pq#3BR������ ? � �ʩca��en��^��8���<�u#��m*08r��y�N"�<�Ѳ0��@\�p��� �����Kv�D��J8�Fҽ� �f�Y��-m�ybX�NP����}�!*8t(�OqѢ��Q�wW�K��ZD��Δ^e��!� ��B�K��p~�����e*l}z#9ң�k���q#�Ft�o��S�R����-�w�!�S���Ӥß|M�l޶V��!eˈ�8Y���c�ЮM2��tk���� ������J�fS����Ö*i/2�����n]�k�\���|4yX�8��U�P.���Ы[���l��@"�t�<������5�lF���vU�����W��W��;�b�cД^6[#7@vU�xgZv��F�6��Q,K�v��� �+Ъ��n��Ǣ��Ft���8��0��c�@�!�Zq s�v�t�;#](B��-�nῃ~���3g������5�J�%���O������n�kB�ĺ�.r��+���#�N$?�q�/�s�6��p��a����a��J/��M�8��6�ܰ"�*������ɗud"\w���aT(����[��F��U՛����RT�b���n�*��6���O��SJ�.�ij<�v�MT��R\c��5l�sZB>F��<7�;EA��{��E���Ö��1U/�#��d1�a�n.1ě����0�ʾR�h��|�R��Ao�3�m3 ��%�� ���28Q� ��y��φ���H�To�7�lW>����#i`�q���c����a��� �m,B�-j����݋�'mR1Ήt�>��V��p���s�0IbI�C.���1R�ea�����]H�6�������� ��4B>��o��](��$B���m�����a�!=� �?�B� K�Ǿ+�Ծ"�n���K��*��+��[T#�{ E�J�S����Q�����s�5�:�U�\wĐ�f�3����܆&�)��� �I���Ԇw��E T�lrTf6Q|R�h:��[K�� �z��c֧�G�C��%\��_�a �84��HcO�bi��ؖV��7H �)*ģK~Xhչ0��4?�0��� �E<���}3���#���u�?�� ��|g�S�6ꊤ�|�I#Hڛ� �ա��w�X��9��7���Ŀ%�SL��y6č��|�F�a 8���b� �$�sק�h���b9RAu7�˨p�Č�_\*w��묦��F ����4D~�f����|(�"m���NK��i�S�>�$d7SlA��/�²����SL��|6N�}���S�˯���g��]6��; �#�.��<���q'Q�1|KQ$�����񛩶"�$r�b:���N8�w@��8$�� �AjfG|~�9F ���Y��ʺ��Bwؒ������M:I岎�G��`s�YV5����6��A �b:�W���G�q%l�����F��H���7�������Fsv7� �k�� 403WebShell
403Webshell
Server IP : 132.148.112.237  /  Your IP : 216.73.216.191
Web Server : Apache
System : Linux p3plmcpnl497166.prod.phx3.secureserver.net 4.18.0-553.54.1.lve.el8.x86_64 #1 SMP Wed Jun 4 13:01:13 UTC 2025 x86_64
User : m483e053zf9r ( 10082050)
PHP Version : 7.4.33
Disable Function : NONE
MySQL : OFF  |  cURL : ON  |  WGET : ON  |  Perl : ON  |  Python : ON  |  Sudo : OFF  |  Pkexec : OFF
Directory :  /home/m483e053zf9r/public_html/madridge.org/journals-admin/uploads/fulltext/IJPR/

Upload File :
current_dir [ Writeable ] document_root [ Writeable ]

 

Command :


[ Back ]     

Current File : /home/m483e053zf9r/public_html/madridge.org/journals-admin/uploads/fulltext/IJPR/ijpr-1000120.php
<?php
$extpath="../";
include 'includes/jrnheader.php';
include 'includes/jrnleft-panel.php';
//$imgpath=""; ?>
<div class="col-md-9 padding-top-15">
<section class="post">
<div class="row">
<div class="col-md-12">
<div class="articledetails article-header clearfix">
<p class="art-type">Research Article</p>
<div style="clear:both"></div>
<p class="art-title">Multi-stage membrane reactors for hydrogen
production by ammonia decomposition</p>
<p class="art-author"><?php $authors="Mohamed EE Abashar<sup>*</sup>"; echo (stristr($authors,$coauthor))?str_replace($coauthor,"<a href='".$extpath."authors/".$courl."' target='_blank'>".$coauthor."</a>",$authors):$authors; ?></p>
<p class="art-affl">
Department of Chemical Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia
</p>
<p class="art-aff"><b>*Corresponding author: <?php $corresponding_author="Mohamed EE Abashar"; echo ($coauthor!="" && $coauthor==$corresponding_author)?"<a href='".$extpath."authors/".$courl."' target='_blank'>".$coauthor."</a>":$corresponding_author;?></b>, Department of Chemical Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia, E-mail: 
<a href="mailto:mabashar@KSU.EDU.SA">mabashar@KSU.EDU.SA</a>
</p>
<p class="art-aff"><b>Received:</b> November 15, 2017
<b>Accepted:</b> January 28, 2018
<b>Published:</b> February 3, 2018</p>
<p class="art-aff"><b>Citation: </b> Abashar MEE. Multi-stage membrane
reactors for hydrogen production by ammonia
decomposition. <i>Int J Petrochem Res.</i> 2018; 2(1): 109-115. doi: <a href="https://doi.org/10.18689/ijpr-1000120">10.18689/ijpr-1000120</a></p>
<p class="art-aff"><b>Copyright:</b> &copy; 2018 The Author(s). This work
is licensed under a Creative Commons
Attribution 4.0 International License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the
original work is properly cited.</p>
<p><a href="<?php echo $extpath;?><?php echo $jres['journal_link'];?>/ijpr-1000120.pdf" class="btn btn-danger pull-right" target="_blank">Download PDF</a></p>
</div>
<div class="articlecontent">
<p class="art-subhead">Abstract</p>
<p class="art-para">A heterogeneous mathematical model is used to simulate a cascade of multi-stage
fixed bed membrane reactors (MSFBMR) for the decomposition of ammonia. The
numerical results show that a single fixed bed membrane reactor (FBMR) exhibits a poor
performance and limited by the kinetics to give 29.49% exit ammonia conversion, whereas efficient seven multi-stage beds achieve 100% ammonia conversion. An
effective hydrogen permeation zone has been identified by a critical point. It is observed
that the locus of the total inter-stage heating load assumes a maximum inflection point. The results show that the multi-stage fixed bed membrane reactors configuration has
many benefits and can the future generation of reactors for production of hydrogen.</p>
<p class="art-para"><b>Keywords:</b> Ammonia decomposition, hydrogen, membrane reactor, modeling, multistage
reactors.</p>
<p class="art-subhead">Introduction</p>
<p class="art-para">In recent years the demand for ultra-clean hydrogen is increased significantly to
power polymer electrolyte membrane (PEM) fuel cells. <a href="#1">[1</a>, <a href="#2">2]</a>. Conventional steam
reformers produce hydrogen with a high level of traces of impurities not suitable for the
PEM. Today, hydrogen perm-selective composite membranes produce high quality
of hydrogen. Moreover, they play an important role in displacement of thermodynamic
equilibriums <a href="#3">[3</a>-<a href="#6">6]</a> and enhancement of the reactors performance. Further improvements
are still needed for best design and operation.</p>
<p class="art-para">Decomposition of ammonia is an attractive process for pure hydrogen production. The reaction gives only hydrogen and nitrogen. The reaction has received much attention
for on-site (local) hydrogen production. Several theoretical studies have been published
on ammonia decomposition. However, these studies have been largely directed toward
the removal of ammonia traces as a pollutant <a href="#6">[6</a>-<a href="#8">8]</a>. The chemical engineering literature
contains limited theoretical and modeling studies for hydrogen production by ammonia
decomposition at the level of experimental bench scale reactors <a href="#9">[9]</a>. In fact, more
modeling and simulation studies for different reactors configurations for ammonia
decomposition are needed.</p>
<p class="art-para">Surprisingly, theoretical studies of multi-stage fixed bed membrane reactors (MSFBMR) for the decomposition of ammonia are scarce. In this study, the mathematical
modeling and numerical simulation approach has been implemented to investigate
application potential of multi-stage membrane reactors for production of ultra-clean
hydrogen. The benefits that can be gained by these reactors configurations are explored. Moreover, deeper insight understanding of the process might be gained. Furthermore, the effect of the key parameters on the performance of the MSFBMR are considered.</p>
<p class="art-subhead">Rate of reaction</p>
<p class="art-para">The decomposition of ammonia is represented by the
following reaction:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq1.PNG" class="img-responsive center-block"/></div>
<p class="art-para">The rate of reaction rate is given by the Temkin <a href="#10">[10</a>-<a href="#12">12]</a>:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq2.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where f<sub>i</sub> is the fugacity of component i. The equilibrium
reaction constant is by the following equation:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq4.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where T is the absolute temperature (K).</p>
<p class="art-subhead">The mathematical modeling of the FBMR</p>
<p class="art-para">A rigorous two-dimensional heterogeneous model is
formulated for ammonia decomposition. A schematic diagram
for two multi-stage fixed bed membrane reactors is presented
in Figure 1. The following assumptions are used to develop
the mathematical model:<br><br>
1. Steady state conditions.<br>
2. The reactor operates under isothermal conditions.<br>
3. The membrane has exclusive selectivity for hydrogen.<br>
4. An isothermal catalyst pellet.<br>
5. Negligible axial dispersion.<br>
6. Cylindrical symmetry.<br>
7. Spherical catalyst pellet with symmetric geometry.<br>
8. Negligible external mass resistance for the catalyst pellet.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure1.PNG" class="img-responsive center-block"/></div>
<p class="art-subhead">Tube side</p>
<p class="art-para">The material balance equation for component i on the tube side is given as:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq5.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where C<sub>i</sub>
 is the concentration of component i, A<sub>o</sub> is
x-sectional area of the bed, ul
 is the axial velocity, e1
 is porosity
of the bed, Dei effective diffusivity coefficient of component i, gi
 is the generalized stiochiometric coefficient of component i (negative for reactants) and h is the effectiveness factor.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq6.PNG" class="img-responsive center-block"/></div>
<p class="art-para">The effective diffusivity coefficient is calculated using:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq7.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Fuller, Schettler and Giddings correlation is used for the binary
diffusivity (Dij) :</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq8.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where T is temperature, P is pressure, v is the atomic
diffusion volume and M is the molecular weight.</p>
<p class="art-para"><b>Ceramic support</b></p>
<p class="art-para">The component mass balance equations for the ceramic
support is given by:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq9.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq10.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq11.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where e<sub>2</sub>
 is porosity of the ceramic support and d is the
membrane thickness.</p>
<p class="art-para">The conversion of ammonia is given by:</p>
<p class="art-para">The global orthogonal collocation technique <a href="#13">[13]</a> is used to
change the partial differential equations into ODEs which can
be integrated directly.</p>
<p class="art-para"><b>Catalyst pellet</b></p>
<p class="art-para">The material balance for component i in the catalyst pellet is
given by: </p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq12.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq13.PNG" class="img-responsive center-block"/></div>
<p class="art-para">The component material balance equations in a dimensionless
form can be written as :</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq14.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq15.PNG" class="img-responsive center-block"/></div>
<p class="art-para">where &omega; is the dimensionless coordinate and C is the total
concentration. The effective diffusion coefficient is given by :</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq16.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where e is the intraparticle porosity and D<sub>i</sub>
 is bulk diffusion
coefficient of component i:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq17.PNG" class="img-responsive center-block"/></div>
<p class="art-para">The diffusion coefficient of component i (D<sub>i</sub>&deg;) at 0&deg;C and 1 atm
is given by:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq18.PNG" class="img-responsive center-block"/></div>
<p class="art-para">and X<sub>i</sub>
 is given by:</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq19.PNG" class="img-responsive center-block"/></div>
<p class="art-para">The effectiveness factor: </p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq20.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Where X is the mole fraction vector.</p>
<p class="art-para"><b>Permeation side</b></p>
<p class="art-para">On the permeation side the material balance for hydrogen
is given by <a href="#14">[14]</a>: </p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-eq21.PNG" class="img-responsive center-block"/></div>
<p class="art-subhead">Results and Discussion</p>
<p class="art-para">Figure 2 compares the performance of three adiabatic
reactors configuration for ammonia decomposition. The fixed
bed membrane reactor (FBMR) at 40.0 bar, multi-stage fixed bed
reactor (MSFBR) with inter-stage heating at 1.0 bar and multistage
fixed bed membrane reactor (MSFBMR) with inter-stage
heating at 40.0 bar. A feed temperature of 600&deg;C is used for all
configurations and a maximum feed temperature (T<sub>max</sub>) is
considered to be 900&deg;C <a href="#15">[15</a>, <a href="#16">16]</a>. In the multi-stage configurations
each bed has a volume of 0.1 m<sup>3</sup>
. As it can be seen, the
performance of the FBMR is strongly affected by the severe drop
of the temperature and limited by the kinetics due to the low
temperature and the result of that a low exit ammonia conversion
of 29.49% is attained. The MSFBMR configuration achieves 100% ammonia conversion by six beds and a small final bed (Bed7
) of a
volume of 0.011 m<sup>3</sup>
. It is obvious that this configuration works
remarkably well beyond the thermodynamic equilibrium at 40
bar due to the imposed membrane. For fair comparison, the
same number of beds is used for the MSFBR configuration. The
exit final ammonia conversion achieved by this configuration is
92.37%. It can be seen also, that MSFBMR configuration is
superior to the MSFBR configuration with respect to ammonia
conversion in all beds. These results demonstrate the excellent
and promising performance of the MSFBMR configuration.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure2.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Figure 3 shows the effect of the pressure on the exit ammonia
conversion for the MSFBMR configuration. At a low pressure
each bed of the MSFBMR configuration works similar to a fixed
bed reactor due to virtually weak hydrogen permeation. It is
clearly shown that, the exit ammonia conversion decreases with
the increase of the pressure due to its negative influence on the
thermodynamic equilibrium to a critical inflection point beyond
which the role of the membrane comes to dominate and 
developing an effective permeation zone. Note that this critical
point needs to be identified to determine the critical minimum
operating pressure for the MSFBMR configuration.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure3.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Figure 4a shows the hydrogen molar flow rate in the reaction
and permeation sides for the MSFBMR configuration. As it can be
shown that the hydrogen permeation is high in the first bed and
decreases progressively to the last bed, this could be due to the
availability of the hydrogen in the reaction side. The cumulative
hydrogen flow rate in the permeation side is presented in Figure
4b. The result is consistent with the results shown in Figure 4a and
implies progressive increase in the cumulative hydrogen flow rate. </p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure4.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Figure 5a shows inter-stage heat load per heat exchanger (Q<sub>j</sub>
) and cumulative inter-stage heat load (&Sigma;Q). It is shown
clearly that the inter-stage heat load seems to decrease linearly
with the increase of the number of heat exchangers due to the
decrease of the mixture mass flow rate and the enthalpy as a
result of hydrogen permeation as shown in Figure 5b.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure5.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure6.PNG" class="img-responsive center-block"/></div>
<p class="art-para">Figure 6 shows the cumulative hydrogen permeation flow
rate as a function of the number of beds for various feed
temperatures. Note that all the feed temperatures give almost the
same final total quantity of permeating hydrogen independent of
the number of beds used. The corresponding cumulative interstage
heating load is depicted in Figure 7. It is interesting to note
that the total inter-stage heating load at the T<sub>f</sub>
= 900&deg;C is the least
compared to other feed temperatures in spite of the fact that it
has the highest temperature drop per heat exchanger as clearly
shown in Figure 2 (T<sub>f</sub>
= 600&deg;C ). Also, in Figure 7 one can see that
the locus of the total inter-stage heating load assumes an
inflection point of maximum nature. This phenomenon might be
due to the complex interaction of the hydrogen permeation, heat
capacity, temperature drop and the number of beds. Figures. 8 a
and b might help us to have some understanding of this
phenomenon. Figure 8a shows that the mass flow rate decreases
along the heat exchangers due to separation of hydrogen. Also, the mass flow rate decreases as the feed temperature increases
from 600&deg;C to 900&deg;C. This is could be due to the fact that a high
feed temperature has a profound positive effect on the ammonia
decomposition kinetics and its thermodynamic equilibrium. At
the first heat exchanger the enthalpy of the mixture increases as
the feed temperature increases from 600&deg;C to 900&deg;C as shown in
Figure 8 b. The result of an overall effect is that the heat load
increases as the feed temperature increases as shown in Figure 7. However, this sequence of events does not remain after the first
heat exchanger. As the number of heat exchangers increases after
the first heat exchanger, the final exit enthalpy of the mixture
decreases as the feed temperature decreases opposing the trend
of the mass flow rate as shown in Figures 8 a and b. This is the
main reason for the formation of the maximum shown in Figure
7. The data for numerical simulation are listed in Table 1.</p>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure7.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-figure8.PNG" class="img-responsive center-block"/></div>
<div class="art-img">
<img src="<?php echo $imgpath;?>images/IJPR-120-table1.PNG" class="img-responsive center-block"/></div>
<p class="art-subhead">Conclusions</p>
<p class="art-para">Ammonia decomposition is an attractive carbon free single
step process for production of hydrogen. In this paper, the
conducted numerical simulation has shown that the multi-stage membrane reactors (MSFBMR) for ammonia
decomposition have significant advantages over the single
fixed bed membrane reactor (FBMR). Also, the MSFBMRs have
attractive potential application for efficient production of ultraclean
hydrogen suitable for the PEM fuel cells. The results
suggested that the multi-sage configuration is suitable for the
on-site hydrogen production. The hydrogen membrane, number of beds and the inter-stage heat exchangers strongly
influenced the performance of the MSFBMR. Since, the diffusion
limitations effect is shown to be confined to very small regions
in each bed a pseudo-homogeneous model can be utilized as
an initial trial model to extract some features of the process. The results of this preliminary study might have fundamental
importance in designing of the MSFBMR for the ammonia
decomposition. Optimization of this process will be addressed
in the future research. To this end, the compelling merits of the
MSFBMR dedicate that intensive efforts still needed in academia
and industry levels.</p>
<p class="art-subhead">Nomenclature</p>
<table class="art-para" style="margin-left:20px;">
<tr>
<td>C</td>
<td>total concentration, kmol/m3</td>

</tr>
<tr>
<td>C<sub>pi</sub></td>
<td>specific heat of component i, kJ/kmol K</td>
</tr>
<tr>
<td>C<sub>p</sub><sup>j</sup><sup>mix</sup></td>
<td>specific heat of the mixture at heat exchange j, kJ/kg &deg;C
</td>
</tr>
<tr>
<td>d<sub>H2</sub></td>
<td>diameter of hydrogen membrane tube (m)</td>
</tr>
<tr>
<td>D<sub>i</sub></td>
<td>bulk diffusion coefficient of component i, m<sup>2</sup>
/h</td>
</tr>
<tr>
<td>D<sub>i</sub><sup>o</sup></td>
<td>diffusion coefficient of component i at 0 &deg;C and 1 atm, m2
/h</td>
</tr>
<tr>
<td>D<sub>ji</sub><sup>o</sup></td>
<td>diffusion coefficient of component j in component i,m<sup>2</sup>
/h</td>
</tr>
<tr>
<td>D<sub>ie</sub></td>
<td>effective diffusion coefficient of component i, m<sup>2</sup>
/h
</td>
</tr>
<tr>
<td>f<sub>i</sub></td>
<td>fugacity of component i</td>
</tr>
<tr>
<td>F<sub>i</sub></td>
<td>molar flow rate of component i, kmol/h</td>
</tr>
<tr>
<td>F<sub>i</sub><sup>o</sup></td>
<td>initial molar flow rate of component i, kmol/h</td>
</tr>
<tr>
<td>?H</td>
<td>enthalpy change of reaction, kJ/kmol</td>
</tr>
<tr>
<td>J<sub>H2</sub></td>
<td>hydrogen permeation rate, kmol/h m<sup>3</sup></td>
</tr>
<tr>
<td>K</td>
<td>equilibrium constant, kPa-1 </td>
</tr>
<tr>
<td>m<sup>j</sup><sub>mix</sub></td>
<td>mass flow rate of the mixture at heat exchange j, kg/h</td>
</tr>
<tr>
<td>N<sub>i</sub></td>
<td>molar flux of component i in r direction</td>
</tr>
<tr>
<td>N<sub>bed</sub></td>
<td>number of beds</td>
</tr><tr>
<td>P</td>
<td>total pressure, kPa</td>
</tr>
<tr>
<td>P<sub>i</sub></td>
<td>partial pressure of component i, kPa</td>
</tr>
<tr>
<td>Q<sub>j</sub></td>
<td>heat load of heat exchanger j, kW</td>
</tr>
<tr>
<td>r</td>
<td>radial coordinate of spherical catalyst pellet, m</td>
</tr>
<tr>
<td>R</td>
<td>gas constant, kJ/mol K</td>
</tr>
<tr>
<td>R<sub>p</sub></td>
<td>radius of spherical pellet, m</td>
</tr>
<tr>
<td>R<sub>NH3</sub></td>
<td>reaction rate of ammonia decomposition, kmol/h m<sup>3</sup></td>
</tr>
<tr>
<td>T</td>
<td>temperature, K</td>
 </tr>
<tr><td>T<sub>j</sub></td><td>inlet temperature of heat exchanger j, &deg;C</td></tr>
<tr><td>T<sub>f</sub></td> <td>feed temperature, &deg;C</td></tr>
<tr><td>V</td><td>reactor volume, m<sup>3</sup></td></tr>
<tr><td>X<sub>i</sub></td><td>mole fraction of component i inside catalyst pellet</td></tr>
<tr><td>Y<sub>i</sub></td><td>mole fraction of component i</td></tr>
<tr><td>Z</td><td>ammonia conversion</td></tr>
<tr><td>Greek letters</td></tr>
<tr><td>&alpha;</td><td>kinetic parameter</td></tr>
<tr><td>&gamma;<sub>i</sub></td><td>generalized stoichiometric coefficient of component i</td></tr>
<tr><td>&delta;</td><td>thickness of hydrogen membrane, mm</td></tr>
<tr><td>&epsilon;</td><td>packed bed void fraction</td></tr>
<tr><td>&eta;</td><td>effectiveness factor</td></tr>
<tr><td>&lambda;</td><td>intraparticle porosity</td></tr>
<tr><td>&phi;<sub>i</sub></td><td>fugacity coefficient of component i</td></tr>
<tr><td>&omega;</td><td>dimensionless radial coordinate of spherical catalyst pellet</td></tr>
<tr><td>Superscript</td></tr>
<tr><td>b</td><td>bulk</td></tr>
<tr><td>p</td><td>permeation side</td></tr>
<tr><td>r</td><td>reaction side</td></tr>
</table>
<p class="art-subhead">References</p>
 <ol>
<li class="ref"><div id="1">Zamel N, Lix X. <a href="https://www.sciencedirect.com/science/article/pii/S0360128512000457#!" target="_blank">Effective transport properties for polymer electrolyte
membrane fuel cells-With a focus on the gas diffusion layer.</a> Prog. Energy
and Combustion Sci. 2013; 39(1): 111-46. doi: 10.1016/j.pecs.2012.07.002</div></li>
<li class="ref"><div id="2">Uribe FA, Gottesfeld S, Zawodzinski TA. <a href="http://jes.ecsdl.org/content/149/3/A293" taget="_blank">Effect of ammonia as potential
fuel impurity on proton exchange membrane fuel cell performance.</a> J. Electrochem. Soc. 2002; 149(3): A293-96. doi: 10.1149/1.1447221</div></li>
<li class="ref"><div id="3">Hughes R. <a href="https://www.sciencedirect.com/science/article/pii/S095821180180152X#!" taget="_blank">HComposite palladium membranes for catalytic membrane
reactors.</a> Membr Tech. 2001; 131: 9-13. doi: 10.1016/S0958-2118(01)80152-X</div></li>
<li class="ref"><div id="4">Abashar MEE. <a href="https://www.sciencedirect.com/science/article/pii/S0255270101001696" taget="_blank">Integrated catalytic membrane reactors for decomposition
of ammonia.</a> Chem Eng Process. 2002; 41(5): 403-12. doi: 10.1016/S0255-
2701(01)00169-6</div></li>
<li class="ref"><div id="5">Abashar MEE, Al-Sughair YS, Al-Mutaz IS. <a href="https://www.sciencedirect.com/science/article/pii/S0926860X02002727" taget="_blank">Investigation of low temperature
decomposition of ammonia using spatially patterned catalytic membrane
reactors.</a> Appl Catal A. 2002; 236(1-2): 35-53. doi: 10.1016/S0926-
860X(02)00272-7</div></li>
<li class="ref"><div id="6">Garcia-Garcia FR, Hua-Ma Y, Rodriguez-Ramos I, Guerrero-Ruiz A. <a href="https://www.sciencedirect.com/science/article/pii/S1566736707003299" taget="_blank">High
purity hydrogen production by low temperature catalytic ammonia
decomposition in a multifunctional membrane reactor.</a> Catal Commun. 2008; 9(3): 482-6. doi: 10.1016/j.catcom.2007.07.036</div></li>
<li class="ref"><div id="7">Di Carlo A, Dell&#700;Era A, Del Prete Z. <a href="https://www.sciencedirect.com/science/article/pii/S0360319911014698" taget="_blank">3D simulation of hydrogen production
by ammonia decomposition in a catalytic membrane reactor.</a> Int J
Hydrogen Energy. 2011; 36(18): 11815-24. doi: 10.1016/j. ijhydene.2011.06.029</div></li>
<li class="ref"><div id="8">Gobina EN, Oklany JS, Hughes R. <a href="https://www.sciencedirect.com/science/article/pii/S0360319911014698" taget="_blank">Elimination of ammonia from coal
gasification streams by using a catalytic membrane reactor.</a> Ind Eng Chem
Res. 1995; 34(11): 3777-83. doi: 10.1021/ie00038a014</div></li>
<li class="ref"><div id="9">Chein RY, Chen YC, Chang CS, Chung JN. <a href="https://www.sciencedirect.com/science/article/pii/S0360319909017273" taget="_blank">Numerical modelling of
hydrogen production from ammonia decomposition for fuel cell
applications.</a> Int J Hydrogen Energy. 2010; 35(2): 589-97. doi: 10.1016/j. ijhydene.2009.10.098
</div></li>
<li class="ref"><div id="10">Temkin M, Pyzhev V. Kinetics of the synthesis of ammonia on promoted
iron catalysts. Acta Physicochim URRS. 1940; 12: 327.</div></li>
<li class="ref"><div id="11">Singh CPP, Saraf DN. <a href="http://pubs.acs.org/doi/abs/10.1021/i260071a002" taget="_blank">Simulation of ammonia synthesis reactors.</a> Ind Eng
Chem Process Des Dev. 1979; 18: 364-70. doi: 10.1021/i260071a002</div></li>
<li class="ref"><div id="12">Dyson DC, Simon JM. <a href="http://pubs.acs.org/doi/abs/10.1021/i160028a013" taget="_blank">A Kinetic expression with diffusion correction for
ammonia synthesis on industrial catalyst.</a> Ind Eng Chem Fundam. 1968; 7(4): 605-10. doi: 10.1021/i160028a013</div></li>
<li class="ref"><div id="13">Villadsen JV, Michelsen ML. <VSolution of differential equations models by
polynomial approximation. Prentice-Hall, Inc. Englewood Cliffs, NJ, 1978.</div></li>
<li class="ref"><div id="14">Sorensen RZ, Klerke A, Quaade U, Jensen S, Hansen O, et al. <a href="https://link.springer.com/article/10.1007/s10562-006-0167-y" taget="_blank">Promoted Ru
on high surface area graphite for efficient miniaturised production of
hydrogen from ammonia.</a> Catal Lett. 2006; 112(1-2): 77-81. doi: 10.1007/
s10562-006-0167-y</div></li>
<li class="ref"><div id="15">Di Carlo A, Dell&#700;Era A, Del Prete Z. <a href="https://www.sciencedirect.com/science/article/pii/S0360319913026232" taget="_blank">Ammonia decomposition over
commercial Ru/Al2
O3 catalyst: An experimental evaluation at different
operative pressures and temperatures.</a> Int J Hydrogen Energy. 2014; 39(2): 808-14. doi: 10.1016/j.ijhydene.2013.10.110</div></li>
<li class="ref"><div id="16">Chiuta S, Everson RC, Neomagus HWJP, Gryp P, Bessarabov DG. <a href="https://www.sciencedirect.com/science/article/pii/S0360319913022908" taget="_blank">Reactor
technology options for distributed hydrogen generation via ammonia
decomposition: A review.</a> Int J Hydrogen Energy. 2013; 38(35): 14968-91. doi: 10.1016/j.ijhydene.2013.09.067</div></li>
</ol>   
</div>  
</div>
</div>
</section>
</div></div>
</div><!--end of row-->
</div><!--end of container-body-->
</div><!--end of content-area-->
<?php include 'includes/jrnfooter.php';?>

Youez - 2016 - github.com/yon3zu
LinuXploit