Thermal Effects on Drying Performance, Kinetics, and Quality Characteristics of Paddy

M Yahya; Zido Yuwazama; Dedi Wardianto; Arfidian Rachman; Ismet Eka Putra; Putra Andi Kolala

Authors

M Yahya Department of Mechanical Engineering, Institut Teknologi Padang, Indonesia Author https://orcid.org/0000-0002-0498-5869
Zido Yuwazama Department of Mechanical Engineering, Institut Teknologi Padang, Indonesia Author https://orcid.org/0009-0007-2493-0877
Dedi Wardianto Department of Mechanical Engineering, Institut Teknologi Padang, Indonesia Author https://orcid.org/0009-0002-4431-2236
Arfidian Rachman Department of Mechanical Engineering, Institut Teknologi Padang, Indonesia Author https://orcid.org/0000-0003-1856-6259
Ismet Eka Putra Department of Mechanical Engineering, Institut Teknologi Padang, Indonesia Author
Putra Andi Kolala Department of Mechanical Engineering, Institut Teknologi Sumatera, Indonesia Author https://orcid.org/0009-0008-8779-497X

Keywords:

Paddy, Drying, Kinetic, Quality, Performance

Abstract

A solar hybrid continuous dryer (SHCD) was developed to overcome the limitations of conventional solar batch drying systems for paddy. This study investigates the thermal effects on drying performance, drying kinetics, and quality characteristics of paddy at different drying air temperatures. Drying experiments were conducted at average air temperatures of 49.7 °C (Exp 1), 60.0 °C (Exp 2), and 69.6 °C (Exp 3). The results indicate that the SHCD at an air temperature drying of 60.0 °C provides the optimal balance between drying performance, energy efficiency, and product quality. At this temperature, the drying time was significantly reduced, accompanied by higher thermal efficiency and superior rice quality compared to other conditions. In contrast, drying at 49.7 °C resulted in prolonged drying time, whereas drying at 69.6 °C led to reduced thermal efficiency and deterioration in product quality. Moreover, the SHCD at 60.0 °C reduced the paddy mass from 420 kg (16.80% wet basis) to 407.63 kg (14.17% wet basis) within 165.4 min. The average drying rate, specific moisture extraction rate (SMER), and specific energy consumption (SEC) were 2.849 kg/h, 0.125 kg/kWh, and 15.649 kWh/kg, respectively, with a maximum thermal efficiency of 17.14%. Quality analysis showed that the percentages of head rice, broken rice, and rice groats were 85.60 ± 0.65%, 8.73 ± 1.98%, and 4.92 ± 1.67%, respectively. Furthermore, the drying kinetics analysis revealed that the moisture ratio (MR) data were best described by the Page model, indicating its suitability for predicting paddy drying behavior in the SHCD system. These findings present that temperature optimization plays a critical role in enhancing drying efficiency and maintaining product quality in continuous solar drying systems.

References

[1] BPS (Badan Pusat Statistik Indonesia), “Statistik Indonesia,” Jakarta, 2019.

[2] Bonazzi, F. Courteis, C. Geneste, M. C. Lahon, & J. Bimbent, “Influence of drying conditions on the processing quality of rough rice,” Drying Technology, vol. 51, no. 3, pp. 1141–1157, 1997.

[3] D. B. Brooker, F. W. Bakker–Arkema, & C. W. Hall, “Drying and storage of grains and oilseeds,” New York: Van Nostrand Reinhold. 1992.

[4] D. C. Wang, & Y. C. Lee, “Performance evaluation of reversible air flow drying in circulating dryer,” Int. Journal of Advances in Chemical Eng. & Biological Science, vol. 4, no. 1, pp. 185–190, 2017.

[5] R. Thahir, “Pengaruh aliran udara dan ketebalan pengeringan terhadap mutu gabah keringannya,” Buletin Enjiniring Pertanian VII (1&2), 1–5. 2000.

[6] Astuti, “Pengeringan padi dalam unggun bergerak dua tahap”. Institut Teknologi Bandung: Skripsi, 2007.

[7] A. Karbassi, & Z. Mehdizabeh. “Drying rough rice in a fluidized bed dryer”. Journal of Agricultural Science and Technology, vol. 10, no. 3, pp. 233–241. 2008.

[8] M. Yahya, H. Fahmi, & H. Hasibuan, “Experimental performance analysis of a pilot-scale biomass-assisted recirculating mixed-flow dryer for drying paddy,” International Journal of Food Science, pp. 1–15, 2022.

[9] M. Yahya, H. Fahmi, R. Hasibuan, & A. Fudholi, “Development of hybrid solar-assisted heat pump dryer for drying paddy,” Case Studies in Thermal Engineering, vol. 45, 102936, 2023.

[10] E. K. Akpinar, “Drying of mint leaves in a solar dryer and under open sun: Modelling, performances analyses,” Energy Conversion and Management, vol. 51, pp. 2407–2418, 2010.

[11] M. Yahya, H. Fahmi, A. Fudholi, & K. Sopian, “Performance and economic analyses on solar-assisted heat pump fluidised bed dryer integrated with biomass furnace for rice drying,” Solar Energy, vol. 174, pp. 1058–1067, 2018.

[12] M. S. H. Sarker, M. N. Ibrahim, N. Ab. Aziz, & P. M. Salleh, “Energy and rice quality aspects during drying of freshly harvested paddy with industrial inclined bed dryer,” Energy Conversion and Management, vol. 77, pp. 389–395, 2014.

[13] C. W. Cao, D.Y. Yang, & Q. Liu, “Research on modeling and simulation of mixed-flow grain dryer,” Drying Technology, vol. 25, pp. 681–687, 2007.

[14] J. Prasad, & V.K. Vijay, “Experimental studies on drying of Zingiber officinale, Curcuma l. and Tinosopora cardifolia in solar-biomass hybrid dryer,” Renewable Energy, vol. 30, pp. 2097–2109, 2005.

[15] M. Yahya, “Design and performance evaluation of a solar assisted heat pump dryer integrated with biomass furnace for red chilli,” International Journal of Photoenergy, pp. 1–14, 2016.

[16] M. Yapa, “Design and testing of pilot continuous fluidized bed paddy dryer,” M.Eng thesis, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand, 139, 1994.

[17] S. Soponronnarit, M. Yapha, & S. Prachayawarakorn, “Crossflow fluidized bed paddy dryer: prototype and commercialization,” Drying Technology, vol. 13, no. 8–9, pp. 2207–2216, 1995.

[18] M. C. Ndukwu, M. Simo-Tagne, F. I. Abam, O. S. Onwuka, & L. Bennamoun, “Exergetic sustainability and economic analysis of hybrid solar-biomass dryer integrated with copper tubing as heat exchanger,” Heliyon, vol. 6, no. 2, e03401, 2020.

[19] H. T. Jokiniemi, & J. M. Ahokas, “Drying process optimisation in a mixed-flow bacth grain dryer,” Biosystems Engineering, vol. 121, pp. 209–220, 2014.

[20] Y. M. Yunus, H. H. Al-Kayiem, & K. A. K. Albaharin, “Design of a biomass burner/gas-to-gas heat exchanger for thermal backup of a solar dryer,” Journal of Applied Sciences, vol. 11, no. 11, pp. 1929–1936, 2011.

[21] M. A. Billiris, & T. J. Siebenmorgen, “Energy use and efficiency of rice drying systems II. Commercial, cross-flow dryer measurements,” Applied Engineering in Agriculture, vol. 30, no. 2, pp. 217-226, 2014.

[22] W. Jittanit, N. Saeteaw, & A. Charoenchaisri, “Industrial paddy drying and energy saving options,” Journal of Stored Products Research, vol. 46, pp. 209–213, 2010.

[23] M. A. Leon, & S. Kumar, “Design and performance evaluation of a solar-assisted biomass drying system with thermal storage,” Drying Technology, vol. 26, pp. 936–947, 2008.

[24] M. N. Ibrahim, M. S. H. Sarker, N. Ab Aziz, & P. M. Salleh, “Drying performances and milling quality of rice during industrial fluidized bed drying of paddy in Malaysia,” Pertanika Journal of Science and Technology, vol. 23, no. 2, 297–309, 2015.

[25] R. J. Pontawe, R. C. Martinez, N. T. Asuncion, & R. B. Villacorte, “Development of a fully-automated pilot-scale model fluidized bed drying system for complete drying of paddy,” Asian Journal of Applied Sciences, vol. 3, no. 6, pp. 747–758, 2015.

[26] S. Mehran, M. Nikian, M. Ghazi, H. Zareiforoush, & I. Bagheri, “Experimental investigation and energy analysis of a solar-assisted fluidizedbed dryer including solar water heater and solar-powered infrared lamp for paddy grains drying,” Solar Energy, vol. 190, pp. 167–184, 2019.