Humidity Control for Air Circulation in the Drying Process
Keywords:air humidity ratio, drying, humidity control, dynamical system identification
Recycling exhaust air is acknowledged as a method to reduce the energy consumption of agricultural products in the dryer. This study investigates the performance of an air circulation system at a laboratory scale and develops a feedback control compensator for optimizing the drying air circulation process. A servo motor is employed to drive a valve, to feed the exhaust drying air with high temperature and humidity back in different proportions. The system is controlled using an Arduino DUE microcontroller, which communicates data with MATLAB/Simulink. The system identification methodology is employed to analyze the mathematical model of the system. The result indicates that the response of the system meets the acceptance criteria when the percent overshoot is less than 25%, and the settling time is within 60 seconds (with a 2% error tolerance). Evaluation of control system performance during equilibrium employs R2 and RMSE values.
N. K. Fukagawa and L. H. Ziska, “Rice: Importance for Global Nutrition,” Journal of Nutritional Science and Vitaminology, vol. 65, no. Supplement, pp. S2-S3, 2019.
S. Roman, L. M. Sánchez-Siles, and M. Siegrist, “The Importance of Food Naturalness for Consumers: Results of a Systematic Review,” Trends in Food Science & Technology, vol. 67, pp. 44-57, September 2017.
D. Kumar and P. Kalita, “Reducing Postharvest Losses during Storage of Grain Crops to Strengthen Food Security in Developing Countries,” Foods, vol. 6, no. 1, article no. 8, January 2017.
A. Müller, M. T. Nunes, V. Maldaner, P. C. Coradi, R. S. de Moraes, S. Martens, et al., “Rice Drying, Storage and Processing: Effects of Post-Harvest Operations on Grain Quality,” Rice Science, vol. 29, no. 1, pp. 16-30, January 2022.
R. O. Lamidi, L. Jiang, P. B. Pathare, Y. D. Wang, and A. P. Roskilly, “Recent Advances in Sustainable Drying of Agricultural Produce: A Review,” Applied Energy, vol. 233-234, pp. 367-385, January 2019.
M. Aghbashlo, H. Mobli, S. Rafiee, and A. Madadlou, “A Review on Exergy Analysis of Drying Processes and Systems,” Renewable and Sustainable Energy Reviews, vol. 22, pp. 1-22, June 2013.
R. Indiarto, A. H. Asyifaa, F. C. A. Adiningsih, G. A. Aulia, and S. R. Achmad, “Conventional and Advanced Food-Drying Technology: A Current Review,” International Journal of Scientific & Technology Research, vol. 10, no. 1, pp. 99-107, January 2021.
W. Jittanit, N. Saeteaw, and A. Charoenchaisri, “Industrial Paddy Drying and Energy Saving Options,” Journal of Stored Products Research, vol. 46, no. 4, pp. 209-213, October 2010.
M. H. T. Mondal, K. S. P. Shiplu, K. P. Sen, J. Roy, and M. S. H. Sarker, “Performance Evaluation of Small Scale Energy Efficient Mixed Flow Dryer for Drying of High Moisture Paddy,” Drying Technology, vol. 37, no. 12, pp. 1541-1550, 2019.
M. Yapha, P. Bunyawanichakul, and N. Hayinilah, “Must Flow Dryer for Rough Rice,” The Second International Conference on Green Computing, Technology and Innovation, the Asia Pacific University of Technology and Innovation, pp. 26-30, March 2014.
P. Thauynak, M. Chuchonak, M. Yapha, and P. Bunyawanichakul, “Influences of Flow Velocity of Hot Air to Moisture Content Reduction of Paddy in Must Flow Paddy Dryer,” Srinakharinwirot Engineering Journal, vol. 9, no. 1, pp. 28-35, July 2014. (In Thai)
J. Havlík, T. Dlouhý, and M. Sabatini, “The Effect of the Filling Ratio on the Operating Characteristics of an Indirect Drum Dryer,” Acta Polytechnica, vol. 60, no. 1, pp. 49-55, March 2020.
S. Firouzi, M. R. Alizadeh, and D. Haghtalab, “Energy Consumption and Rice Milling Quality Upon Drying Paddy with a Newly-Designed Horizontal Rotary Dryer,” Energy, vol. 119, pp. 629-636, January 2017.
Ministry of Energy (Thailand), “20-Year Energy Efficiency Development Plan (2011-2030),” https://www.eppo.go.th/images/POLICY/ENG/EEDP_Eng.pdf, January 23, 2023.
R. P. Amantéa, M. Fortes, and G. T. Santos, “Exergy Analysis Applied to the Design of Grain Dryers with Air Flow Recirculation,” 2012 Dallas, Texas, July 29-August 1, 2012. American Society of Agricultural and Biological Engineers, article no. 121340983, 2012.
B. Sila, A. Pakdeekaew, K. Treeamnak, and T. Treeamnak, “Effect of Exhaust Air Recirculation on Energy Consumption in Air Heating System,” Proceeding of 14th Conference of Electrical Engineering Network 2022, May 2022. (In Thai)
H. Darvishi, M. Azadbakht, and B. Noralahi, “Experimental Performance of Mushroom Fluidized-Bed Drying: Effect of Osmotic Pretreatment and Air Recirculation,” Renewable Energy, vol. 120, pp. 201-208, May 2018.
R. A. Chayjan, A. Ghasemi, and M. Sadeghi, “Stress Fissuring and Process Duration during Rough Rice Convective Drying Affected by Continuous and Stepwise Changes in Air Temperature,” Drying Technology, vol. 37, no. 2, pp. 198-207, 2019.
M. Tohidi, M. Sadeghi, and M. Torki-Harchegani, “Energy and Quality Aspects for Fixed Deep Bed Drying of Paddy,” Renewable and Sustainable Energy Reviews, vol. 70, pp. 519-528, April 2017.
A. Pakdeekaew, K. Treeamnuk, T. Treeamnuk, and N. Wongbubpa, “Application of Pulse Width Modulation Technique in Air Humidity Control System,” Agriculture and Natural Resources, vol. 57, no. 2, pp. 321-330, March-April 2023.
I. Golpour, R. P. Guiné, S. Poncet, H. Golpour, R. Amiri Chayjan, and J. Amiri Parian, “Evaluating the Heat and Mass Transfer Effective Coefficients during the Convective Drying Process of Paddy (Oryza sativa L.),” Journal of Food Process Engineering, vol. 44, no. 9, article no. e13771, September 2021.
2009 ASHRAE Handbook: Fundamentals, SI ed., Atlanta GA: American Society of Heating Refrigeration and Air-Conditioning Engineers, 2009
L. A. Aloo, P. K. Kihato, and S. I. Kamau, “DC Servomotor-Based Antenna Positioning Control System Design Using Hybrid PID-LQR Controller,” European International Journal of Science and Technology, vol. 5, no. 2, pp. 17-31, March 2016.
A. Rajasekhar, P. Kunathi, A. Abraham, and M. Pant, “Fractinal Order Speed Control of DC Motor Using Levy Mutated Artificial Bee Colony Algorithm,” 2011 World Congress on Information and Communication Technologies, pp. 7-13, December 2011.
R. W. Fox, A. T. McDonald, P. J. Pritchard, and J. W. Mitchell, Fluid Mechanics, London: Wiley Global Education, 2016.
M. Rajalakshmi, V. Saravanan, V. Arunprasad, C. A. T. Romero, O. I. Khalaf, and C. Karthik, “Machine Learning for Modeling and Control of Industrial Clarifier Process,” Intelligent Automation & Soft Computing, vol. 32, no. 1, 2022.
L. Ljung, “Perspectives on System Identification,” Annual Reviews in Control, vol. 34, no. 1, pp. 1-12, April 2010.
K. Ogata, Modern Control Engineering, 5th ed., Boston: Prentice-Hall, 2010.
T. Pongam, J. Srisertpol, and V. Khompis, “PI Controller Design for Temperature Control of Reheating Furnace Walking Hearth Type in Setting Up Process,” Advanced Materials Research, vol. 748, pp. 801-806, August 2013.
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