Monitoring of process variables in hybrid photovoltaic dryers using soft sensors: application in food drying

• Grant number: 17/21890-5
• Support Opportunities: Regular Research Grants
• Duration: February 01, 2018 - January 31, 2020
• Field of knowledge: Engineering - Chemical Engineering - Industrial Operations and Equipment for Chemical Engineering
• Principal Investigator: Gustavo Nakamura Alves Vieira
• Grantee: Gustavo Nakamura Alves Vieira
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The moisture content and colorimetric parameters of foodstuff are important variables for the quality monitoring of these products, during and after drying processes. However, these are variables which are difficult to measure by online procedures, being thus commonly measured by sampling and offline procedures. This approach is not suitable for the monitoring of variables in chemical processes in general, considering that the process is operated in an open-loop manner while the measurement is carried out. Alternatively, one might use variables whose measurement is quicker and which are related to variables whose measurement is more time consuming by using physical mathematical models, that is, variables whose measurement is more difficult might be inferred by soft sensors. In this context, the objective of this project is the development of soft sensors for the measurement of moisture content and colorimetric parameters (in terms of the CIELab coordinates), aiming the on line sensing of these variables during drying in a hybrid photovoltaic solar dryer. This dryer was chosen considering the possibility of application in processing of spices and medicinal plants in the context of familiar agriculture. Firstly, the process will be modeled, based on heat and mass transfer equations and by fitting some of the physical-mathematical model parameters to experimental data. Afterwards, the model will be incorporated to the data acquisition interface, which will provide inferred values of the moisture content and colorimetric coordinates, based on other process variables which can be measured more quickly. The robustness and precision of the soft sensor will be evaluated based on new drying experiments. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

HIDALGO, LETICIA FERRARESI; CANDIDO, MARIANA NASCIMENTO; NISHIOKA, KARINA; FREIRE, JOSE TEIXEIRA; ALVES VIEIRA, GUSTAVO NAKAMURA. Natural and forced air convection operation in a direct solar dryer assisted by photovoltaic module for drying of green onion. Solar Energy, v. 220, p. 24-34, MAY 15 2021. (17/21890-5, 18/24132-7, 18/23762-7, 19/17654-0)