Drying of grape pomace with a double pass solar collector

AKTAŞ M., ŞEVİK S., Dolgun E. C. , Demirci B.

DRYING TECHNOLOGY, vol.37, no.1, pp.105-117, 2019 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 1
  • Publication Date: 2019
  • Doi Number: 10.1080/07373937.2018.1441154
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.105-117
  • Keywords: Double-pass solar air collector, drying efficiency, energy, grape pomace, solar drying, COP, coefficient of performance, DPSAC, double-pass solar air collector, DR, drying rate, g water, g dry matter per min, MR, moisture ratio, SAC, solar air collector, SMER, specific moisture extraction rate, PHENOLIC-COMPOUNDS, TEMPERATURE, EXTRACTION, POLYPHENOLS, SIMULATION, RECOVERY, DESIGN
  • Gazi University Affiliated: Yes


This study aims to analyze the performance of a novel design of the double pass solar air collector (DPSAC)-assisted drying system and investigate the drying kinetics of grape pomace which is an agricultural by-product. The samples were dried to a moisture content of 0.01 g water/g dry matter between 100 and 250 min depending on the weather conditions. The average thermal efficiencies of DPSAC were calculated as 79.77, 79.85, and 69.46%. Average values of the coefficient of performance of DPSAC were determined as 5.32, 5.13, and 4.32. The highest specific moisture extraction rate value was achieved as 617.18 g water/kWh. Whereas the mass transfer coefficient (h(m)) values ranged from 9.15E-11 to 1.04E-7 m/s, the effective moisture diffusivity (D-e) values were obtained between 3.04E-13 and 1.02E-10 m(2)/s. The qualitative analysis showed that the drying using DPSAC may be an alternative for drying applications in terms of short drying time and energy usage. Nevertheless, these results clearly suggest a complex and effective interplay between thermal performance and drying kinetics.