Energy-saving evaluation of a solar integrated vacuum freeze-dryer and building air conditioning system

Abstract

Vacuum freeze-dryer has been widely used in many fields such as food, medicine, and beverage. In the actual operation process, the freeze-dryer and factory buildings need to consume a lot of cold energy. In order to reduce energy consumption, this paper presents a freeze-dryer system using solar energy absorption refrigeration in conjunction with buildings. Through the solar absorption refrigeration system, the cooling capacity is supplied to the freeze-dryer and the building at the same time, so that the cold can be cascaded utilization. The simulation of the system by TRNSYS software shows that the system can greatly reduce the consumption of conventional energy, and it is a new energy-saving measure of vacuum freeze-dryer and building air conditioning.

Effect of pulsed‐vacuum, hot‐air, infrared, and freeze‐drying on drying kinetics, energy efficiency, and physicochemical properties of Ginkgo biloba L. seed

“…Again, freeze‐dryer had a higher SEC compared to the heat‐applied dryers (HD, ID, and PVD) for drying ginkgo seeds with a significant difference ( p < .05). This was due to a more considerable amount of energy to maintain the vacuum, sublimation (Zhou et al, 2019), and circulation (Table 1). A similar pattern was also witnessed for freeze‐drying of ginger slices, apple slices, and purple basil (Altay et al, 2019; Baysal et al, 2015; Osae et al, 2020).…”

“…Using the equations in Table 1, each dryer's total energy consumption was calculated (Beigi, 2016; Jiang et al, 2020; Motevali et al, 2011; Zhou et al, 2019). The moisture extraction rate (MER), specific moisture extraction rate (SMER), and specific energy consumption (SEC) were determined by Equations (4a–c) to assess the effectiveness of those systems (Altay, Hayaloglu, & Dirim, 2019; Jiang et al, 2020): where M wr , E T , t , G , M 0 , and M t denotes the quantity of water removed during drying (kg), total energy supplied (kWh), drying time (hr), the weight of dried GBS (kg), initial MC and final MC of GBS, correspondingly.…”

“…Using the equations in Table 1, each dryer's total energy consumption was calculated (Beigi, 2016;Jiang et al, 2020;Motevali et al, 2011;Zhou et al, 2019). The moisture extraction rate (MER), specific moisture extraction rate (SMER), and specific energy consumption (SEC)…”

“…energy for the hydraulic, E r = energy for the refrigeration, E c = energy for the circulatory, E v = energy for the vacuum, E s = energy for the sublimation (Zhou, Guo, & Lin, 2019)…”

Building integrated renewable energy

“…Solar energy utilization is very important to help reduce the building energy consumption and even achieve net zero energy buildings. Zhou et al (2021) proposed a solar integrated vacuum freeze-dryer and building air conditioning system, where a solar absorption refrigeration system provides cooling to both the building space and the freeze-dryer. Through computer simulation under the TRNSYS environment, it was predicted that 35.2% of the total energy was provided by solar energy.…”