Transport phenomena, thermodynamic analyses, and mathematical modelling of okra convective cabinet-tray drying at different drying conditions
Main Article Content
Abstract
Okra is a vegetable that is highly consumed for its nutritive and health benefits. Due to its highly perishable nature, it is often subjected to hot air drying to increase the shelf-life. Hence, the drying kinetics, moisture diffusivity, heat and mass transfer coefficient, total and specific energy consumption, and exergy (exergetic efficiency, exergetic improvement potential rate, and exergetic sustainability index) are essential parameters required for the drying system design. This study was therefore focused on okra drying data generation for the determination and evaluation of these parameters. The major goal was to utilize the generated data for the development of an innovative process model that can find application in dryer design. A self-designed laboratory cabinet-tray dryer was used for the drying at different drying conditions (temperature (40-70 oC), air velocity (0.5-2.0 m/s), and relative humidity (60-75%)). The obtained results showed that the effective moisture diffusivity ranged from 2.59×10-10 - 7.50×10-10 m2/s while the heat and mass transfer coefficient varied from 1.24-8.07 W/m2K and 1.61×10-7-18.3×10-7 m/s over the drying conditions range, respectively. The energy consumption increased with increasing air velocity, temperature, and relative humidity. The exergy loss rate was higher at higher air velocity, temperature, and relative humidity. The energy and exergetic efficiencies respectively varied from 0.78-4.67% and 65.12-84.96% over the drying conditions range. The exergetic improvement potential rate and the exergetic sustainability index of the drying chamber varied from 0.013-0.201 kW and 2.86-6.65, respectively. An innovative multiple linear regression-Biot-Lag factor model was developed.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
References
Afolabi TJ, Agarry SE. Thin layer drying kinetics and modelling of okra (Abelmoschus Esculentus (L.) Moench) slices under natural and forced convective air drying. Food Sci Qual Manage. 2014;28:35-50.
Kumar D, Prasad S, Murthy GS. Optimization of microwave-assisted hot air drying conditions of okra using response surface methodology. J Food Sci Technol. 2014;51(2):221-32.
Pendre NK, Nema PK, Sharma HP, Rathore SS, Kushwah SS. Effect of drying temperature and slice size on quality of dried okra (Abelmoschus esculentus (L.) Moench). J Food Sci Technol. 2012;49(3):378-81.
Aamir M, Boonsupthin W. Effect of microwave drying on quality kinetics of okra. J Food Sci Technol. 2017;54(5):1239-47.
Klungboonkrong V, Phoungchandang S, Lamsal B. Drying of Orthosiphon Aristaeus leaves: Mathematical modeling, drying characteristics, and quality aspects. Chem Eng Commun. 2018;205(9):1239-51.
Agrawal SG, Methekar RV. Mathematical model for heat and mass transfer during convective drying of pumpkin. Food Bioprod Process. 2017;101:68-73.
Darvishi H. Quality, performance analysis, mass transfer parameters and modeling of drying kinetics of soybean. Braz J Chem Eng. 2017;34(1):143-58.
Castro LMM, Pinheiro MNC. A simple data processing approach for drying kinetics experiments. Chem Eng Commun. 2016;203 (2):258-69.
Akpinar EK, Toraman S. Determination of drying kinetics and convective heat transfer coefficients of ginger slices. Heat Mass Transf. 2016;52:2271-81.
Erbay Z, Icier F. Energy and exergy analyses on drying of olive leaves (Olea European L.) in tray drier. J Food Process Eng. 2011;34:2105-23.
Castro M, Roman C, Echegaray M, Mazza G, Rodriguez R. Exergy analyses of onion drying by convection: influence of dryer parameters on its performance. Entropy. 2018;20:310-4.
Lingayat A, Chandramohan VP, Raju VRK. Energy and exergy analysis on drying of banana using indirect type natural convection solar dryer. Heat Transf Eng. 2020;41(6-7):551-61.
Nwakuba NR, Chukwuezie OC, Asonye GU, Asoegwu SN. Energy analysis and optimization of thin layer drying conditions of okra. Arid Zone J Eng Technol Environ. 2018;14(SP.i4):129-48.
Folayan JA, Osuolale FN, Anawe AL. Data on exergy and exergy analyses of drying process of onion in a batch dryer. Data Brief. 2018;21:1784-93.
Prommas R, Rattanadecho P, Jindarat W. Energy and exergy analyses in drying process of non-hygroscopic porous packed bed using a combined multi-feed microwave-convective air and continuous beltsystem (CMCB). Int Commun Heat Mass Trans. 2012;39:242-50.
Azadbakht M, Torshizi M, Ziaratban A, Aghili H. Energy and exergy analyses during eggplant drying in a fluidized bed dryer. Agric Eng Int: CIGR J. 2017;19(3):177-82.
Mondal MHT, Hossain MA, Sheik MAM, Akhtaruzzaman M, Sarker MSH. Energetic and exergetic investigation of a mixed flow dryer: a case study of maize grain drying. Drying Technol. 2020;39(4):1-16.
Chen C, Venkitasamy C, Zhang W, Deng L, Meng X, Pan Z. Effect of step-down temperature drying on energy consumption and product quality of walnuts. J Food Eng. 2020;285(8):110105.
Agarry SE. Modelling the drying characteristics and kinetics of hot air-drying of un-blanched whole red pepper and blanched bitter leaf slices. Turkish J Agric Food Sci Technol. 2017;5(1):24-32.
Mujaffar S, John S. Thin-layer drying behavior of West Indian lemongrass (Cymbopogan Citratus) leaves. Food Sci Nutr. 2018;6:1085-99.
Said LBH, Najjaa H, Farhat A, Neffati M, Bellagha S. Thin layer convective air drying of wild edible plant (Allium roseum) leaves: experimental kinetics, modeling and quality. J Food Sci Technol. 2015;52(6):3739-49.
Abhishek D, Ramakrishna K, Naik BK. Evaluation of heat and mass transfer coefficients at beetroot-air interface during convective drying. Interfacial Phenom Heat Transf. 2020;8(4):303-19.
Mullen S, Rogers B, Worman H, Martinez EN. The drying of apples in a laboratory tray drier. Chem Eng Edu. 2018;52(1):9-20.
Ndukwu MC, Dirioha C, Abam FI, Ihediwaa VE. Heat and mass transfer parameters in the drying of cocoyam slice. Case Stud Therm Eng. 2017;9:62-71.
Ndukwu MC, Bennamoun L, Anozie O. Evolution of thermo-physical properties of Akuama (Picralima nitida) seed and antioxidants retention capacity during hot air drying. Heat Mass Trans. 2018;54:3533-46.
Guine RPF, Barroca MJ, Silva V. Mass transfer properties of pears for different drying methods. Int J Food Prop. 2013;16(2): 251-62.
Baptestini FM, Correa PC, de Oliveira GHH, Botelho FM, de Oliveira APLR. Heat and mass transfer coefficients and modeling of infrared drying of banana slices. Rev Ceres. 2017;64(5):457-64.
Kaya A, Aydin O, Demirtas C, Akgun M. An experimental study on the drying kinetics of quince. Desalinat. 2007;212(1-3): 328-43.
Taheri-Garavand A, Meda V. Drying kinetics and modeling of savory leaves under different drying conditions. Int Food Res J. 2018;25(4):1357-64.
Velic D, Planinic M, Tomas S, Bilic M. Influence of air flow velocity on kinetics of convection apple drying. J Food Eng. 2004;64:97.
Ju HY, El-Mashad HM, Fang XM, Pan Z, Xiao HW, Liu YH, et al. Drying characteristics and modeling of yam slices under different relative humidity conditions. Drying Technol. 2016;34(3):296-306.
Ju HY, Zhao SH, Mujumdar AS, Zhao HY, Duan X, Zheng ZA, et al. Step-down relative humidity convective air drying strategy to enhance drying kinetics, efficiency, and quality of American ginseng root (Panax quinquefolium). Drying Technol. 2020;38(7):903-16.
Kaveh M, Karami H, Jahanbakhshi A. Investigation of mass transfer, thermodynamics, and greenhouse gases properties in pennyroyal drying. J Food Proc Eng. 2020;43(8):e13446.
Agnihotri V, Jantwal A, Joshi R. Determination of effective moisture diffusivity, energy consumption and active ingredient concentration variation in Inula Racemosa, rhizomes during drying. Ind Crop Prod. 2017;106:40-7.
Dincer I, Sahin AZ. A new model for thermodynamic analysis of a drying process. Int J Heat and Mass Trans. 2004;47(4):645-52.
Wankhade PK, Sapkal RS, Sapkal VS. Drying characteristics of okra slices on drying in hot air dryer. Procedia Eng. 2013;51:371-4.
Olajire AS, Tunde-Akintunde TY, Ogunlakin GO. Drying kinetics and moisture diffusivity study of okra slice. J Food Proc Technol. 2018;9:751-7.
Ouedraogo GWP, Kaboré B, Kam S, Bathiebo DJ. Determination of physical and chemical properties of okra during convective solar drying. Int J Eng Adv Technol. 2017;7(1):76-80.
Roman F, Hensel O. Effect of air temperature and relative humidity on the thin-layer drying of celery leaves (Apium graveolens var. secalinum). Agric Eng Int: CIGR J. 2011;13(2):1-11.
Taheri-Garavand A, Rafiee S, Keyhani A. Effective moisture diffusivity and activation energy of tomato in thin layer dryer during hot air drying. Int Trans J Eng Manage Appl Sci Technol. 2011;2(2):239-48.
Pankaew P, Janjai S, Nilnont W, Phusampao C, Bala BK. Moisture desorption isotherm, diffusivity and finite element simulation of drying of macadamia nut (Macadamia integrifolia). Food Bioprod Process. 2016;100:16-24.
Sigge GO, Hansmann CF, Joubert E. Effect of temperature and relative humidity on the drying rates and drying times of green bell peppers (Capsicum annuum L). Drying Technol. 1998;16(8):1703-14.
Association of official analytical chemists (AOAC). Official methods of analysis. 16th ed. Washington, AOAC; 2015.
Khanali M, Banisharif A, Rafiee S. Modeling of moisture diffusivity, activation energy and energy consumption in fluidized bed drying of rough rice. Heat Mass Trans. 2016;52:2541-9.
Dincer I, Dost SA. Modelling study for moisture diffusivities and moisture transfer coefficients in drying of solid objects. Int J Energy Res. 1996;20:531-9.
Liu X, Hou H, Chen J. Applicability of moisture transfer parameters estimated by correlation between Biot number and lag factor (Bi-G correlation) for convective drying of eggplant slices. Heat Mass Trans. 2013;49:1595-601.
Choi Y, Okos MR. Effects of temperature and composition on the thermal properties of foods. In: Maguer L, Jelen P, editors. Food engineering and process applications. New York: Elsevier; 1986. p. 93-101.
Beigi M. Energy efficiency and moisture diffusivity of apple slices during convective drying. Food Sci Technol. 2016;36(1): 145-50.
Minaei S, Chenarbon HA, Motevali A, Hosseini AA. Energy consumption, thermal utilization efficiency and hypericin content in drying leaves of St John’s Wort (Hypericum Perforatum). J Energy South Africa. 2014;25(3):27-35.
Aghbashlo M, Mobli H, Rafiee S, Madadlou A. Energy and exergy analyses of the spray drying process of fish oil microencapsulation. Biosyst Eng. 2012;111(2):229-41.
Dincer I, Midilli A, Kucuk H. Progress in exergy, energy, and the environment. Switzerland: Springer; 2014.
Sarker MSH, Ibrahim MN, Aziz NA, Punan MS. Energy and exergy analysis of industrial fluidized bed drying of paddy. Energy. 2015;84:131-8.
Ozgen F, Celik N. Evaluation of design parameters on drying of kiwi fruit. Appl Sci. 2019;9(10):1-13.
Taheri-Garavand A, Rafiee S, Keyhani A. Effect of temperature, relative humidity and air velocity on drying kinetics and drying rate of basil leaves. Electron J Environ Agric Food Chem. 2015;10(4):2075-80.
Foroughi-dahr M, Golmohammadi M, Pourjamshidiyan R, Rajabi-hamaneh M, Hashemi SJ. On the characteristics of thin layer drying models for intermittent drying of rough rice. Chem Eng Commun. 2015;202(8):1024-35.
Dai JW, Rao JQ, Wang D, Xie L, Xiao HW, Liu YH, et al. Process-based drying temperature and humidity integration control enhances drying kinetics of apricot halves. Dry Technol. 2015;33(3):365-76.
Doymaz I, Demir H, Yildirim A. Drying of quince slices: effect of pretreatments on drying and rehydration characteristics. Chem Eng Commun. 2015;202(10):1271-9.
Barati E, Esfahani JA. A novel approach to evaluate the temperature during drying of food products with negligible external resistance to mass transfer. J Food Eng. 2013;114:39-46.
Akpinar EK, Dincer I. Application of moisture transfer models to solids drying. Proc Inst Mech Eng A. 2005;219:235-44.
Guine R, Barroca MJ. Estimation of the diffusivities and mass transfer coefficients for the drying of D. Joaquina Pears. World congress on engineering 2013; 2013 Jul 3-5; London, UK. London: IA Eng; 2013. p. 1320-3.
Dincer I, Hussain MM. Development of a new Bi-Di correlation for solids drying. Int J Heat Mass Trans. 2002;45(15):3065-9.
Lee JR, Lau EV. Effects of relative humidity in the convective heat transfer over flat surface using ionic wind. Appl Therm Eng. 2017;114(5):554-60.
Nwakuba NR, Chukwuezie OC, Asonye GU, Asoegwu SN. Influence of process parameters on the energy requirements and dried sliced tomato quality. Eng Rep. 2020;2(2):e12123.
Nwakuba NR, Chukwuezie OC, Osuchukwu LC. Modeling of drying process and energy consumption of onion (Ex-gidankwano Spp.) slices in a hybrid crop dryer. Am J Eng Res. 2017;6(1):44-55.
Motevali A, Minaei S, Banakar A, Ghobadian B, Khoshtaghaza MH. Comparison of energy parameters in various dryers. Energy Convers Manage. 2014;87:711-25.
Icier F, Colak N, Erbay Z, Kuzgunkaya EH, Hepbasli AA. Comparative study on energetic performance assessment for drying of broccoli florets in three different drying systems. Drying Technol. 2010;28:193-204.