Dynamic Modeling of Charge and Discharge of Adsorbed Natural Gas storage Tank

Document Type : Chemistry Article

Authors

1 Persian Gulf University

2 Persian Gulf university

Abstract

Recently, adsorbed natural gas (ANG) has been considered as a low pressure and safe method for storage of natural gas, especially in vehicles. Nevertheless, the usage of the ANG storage system is hindered by the thermal effects due to both heat of adsorption and desorption during the charge and discharge processes and hence, an effective thermal enhancement is essential for the development of this technology. The purpose of this study is the investigation of transient thermal behavior of an ANG tank during charge and discharge cycles. There is a gas diffuser at the center of the tank to improve its temperature fluctuations by changing the flow direction from axial to radial. In this study, mass and energy equations were first derived and the resulting equation system was solved by implicit finite difference numerical method. By solving these equations, radial temperature and pressure distributions of adsorbent bed were obtained over time. Then, the effective parameters on the temperature fluctuations and efficiency of the ANG tank were studied. Numerical results show that the gas diffuser increases dynamic efficiency around 5% during the charge and discharge cycles. The results also show that the time of process, adsorbent bed thermal conductivity, convection heat transfer coefficient, tank geometry and dimensionless Biot and Fourier numbers are important factors on the efficiency enhancement. Also it was shown that high penetration resistance of the adsorbent bed may have a significant impact on the storage capacity and charge process time of the ANG tank.

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[1] ملاشاهی، م.، هاشمی پوررفسنجانی، ح. (1389). "بررسی ذخیره سازی گاز طبیعی به روش جذب سطحی و تشکیل هیدرات در جاذب‌های کربنی مرطوب". مجله مهندسی شیمی، سال 9، شماره 48.
[2] Giraldo L., Moreno-Pirajan J.C. (2011). "Novel Activated Carbon Monoliths for Methane Adsorption Obtained from Coffee Husks". Materials Sciences and Applications, vol. 2, pp. 331- 339.
[3] Chang K.J., Talu O. (1996). "Behavior And Performance of Adsorptive Natural Gas Storage Clinders During Discharge". Applied Thermal Engineering, vol. 16, pp. 359-374.
[4] Herna´ndez-Huesca R., Diaz L., Aguilar-Armenta G. (1999). "Adsorption equilibria and kinetics of CO2 , CH4 and  N2 in natural zeolites". Separation and Purification Technology, vol. 15, pp. 163-173.
[5] Bastos-Neto M., SEurico B., Torres B., Diana C.S., Cileo S., Cavalcante J.R. (2005). "Methane Adsorption Storage Using Microporous Carbons Obtained from Coconut Shells". Adsoption, vol. 11, pp. 911-915.
[6] Rashidi A.M., Lotfi R., Nouralishahi A., Khodagholi A.M, Zare M., Eslamipor F. (2011). "Nanoporous carbons as promising novel methane adsorbents for natural gas technology". Journal of Natural Gas Chemistry, vol. 20, pp. 664- 668.
[7] Arami-Niya A., Ashri Wan Daud W.M., Mjalli F.S., Shafeeyan M.S. (2012). "Production of microporous palm shell based activated carbon for methane adsorption: Modeling and optimization using response surface methodology". Chemical Engineering Research and Design, vol. 90, pp. 776- 784.
[8] Mota J.P.B., Rodriguea A.E., Saatdjian E., Tondeur D. (1997). "Dynamics of Natural Gas Adsorption Storage Systems Employing Activated Carbon. Carbon". vol. 35, pp. 1259-1270.
[9] Mota J.P.B. (1999). "Impact of Gas Composition on Natural Gas Storage by Adsorption". American Institute of chemical engineers, vol. 45, pp. 986–996 .
[10] Zhou L., Li M., Sun Y., Zhou Y. (2001). "Effect of moisture in microporous activated carbon on the adsorption of methane". Carbon, vol. 39, pp. 771- 785.
[11] Lara L.G., Couto P., Sophya D.M.A., Cotta R.M. (2006). "Thermal Control of Adsorbed Natural Gas Reservoirs under Discharge Dynamic Condition". 13th International Heat Transfer Conference, Sydney, Australia, 13-18 August.
[12] Hirata S.C., Couto P., Lara L.G., Cotta R.M. (2009). "Modeling and Hybrid Simulation of Slow Discharge Process of Adsorbed Methane Tanks". International Journal of Thermal Sciences, vol. 48, pp. 1176-1183.
[13] Bastos-Neto M., SEurico B., Torres B., Diana C.S., Cileo S., Cavalcante J.R. (2005). "A Theoretical and Experimental Study of Charge and Discharge Cycles in a Storage Vessel for Adsorbed Natural Gas. Adsorption". Adsorption, vol. 11, pp. 147-157.
[14] Jurumenha, D.S., Sphaier, L. A. (2001). "Suitability analysis of lumped-capacitance formulations for adsorbed gas storage ". Applied Thermal Engineering, vol. 31, pp. 2458-2463.
[15] Biloe, S., Goetz, V., Mauran, S. (2001). "Dynamic Discharge and Performance of a New Adsorbent for Natural Gas Storage". American Institute of Chemical Engineers Journal, vol. 47, pp. 2819-2830.
[16] Suzuki, M. (1990). "Adsorption Engineering". Elsevier Science, Tokyo.
[17] Glueckauf, E. (1955). "Theory of Chromatography Part 10 - Formula for Diffusion into Spheres and Their Application to Chromatography". Transactions of the Faraday Society, vol. 51, pp. 1540-1551.