Experimentation and performance analysis of solar-assisted heat pump dryer for intermittent drying of food chips

2021 ◽  
pp. 1-35
Author(s):  
A Singh ◽  
Jahar Sarkar ◽  
Rashmi Sahoo
Keyword(s):  
Energy Efficiency ◽  
Economic Analysis ◽  
Heat Pump ◽  
Payback Period ◽  
Extraction Rate ◽  
Maximum Enhancement ◽  
Drying Time ◽  
Moisture Extraction ◽  
And Performance ◽  
Drying Efficiency

Abstract A solar-assisted heat pump dryer is fabricated for intermittent drying. The experiment is performed for different intermittency ratios for radish drying using future refrigerant R1234yf. The effects of total drying time (on-period + off-period) on various energetic, exergetic, and economic performances are investigated. Radish chips were dried to extract moisture from 92.4% to 11.9%. Energy efficiency and drying efficiency are estimated higher for a lower intermittency ratio. The moisture extraction rate and specific moisture extraction rate are higher for intermittent drying as compared to continuous drying and increase with a decrease in intermittency ratio. The economic analysis concludes that the payback period is lower for a lower intermittency ratio. The payback period for intermittency ratio of 1, 0.66, 0.33 and 0.2 are estimated as 1.617 years, 1.459 years, 1.384 years, and 1.347 years, respectively. Present experimental thermo-economic analysis reveals that intermittent drying is much better (maximum enhancement of specific moisture extraction rate is 60.6%, that of energy efficiency is 56.4% and maximum reduction of drying cost is 37.9% with studied conditions) than continuous drying.

scholarly journals Effect of tray dryer’s independent variables (drying temperature and air velocity) on the quality of olive pomace and system’s energy efficiency

2018 ◽  
Author(s):  
Mehmet Koç ◽  
Ulaş Baysan ◽  
A. Güngör ◽  
Figen Kaymak-Ertekin
Keyword(s):  
Energy Efficiency ◽  
Specific Energy Consumption ◽  
Oxidation Stability ◽  
Extraction Rate ◽  
Olive Pomace ◽  
Air Velocity ◽  
Drying Time ◽  
Drying Temperature ◽  
Moisture Extraction

In this study, the effects of drying temperature (70, 80, 90°C) and air velocity (0.5, 1.8 m/s) of hot air drying (tray drying) on quality of dried 2-phase olive pomace and system’s energy efficiency were investigated. The drying experiments were carried out in a tray dryer. The effects of drying conditions were evaluated with analyzing drying time, the primary and secondary oxidation and calculating specific moisture extraction rate (SMER), moisture extraction rate (MER) and specific energy consumption (SEC). The results showed that increase in drying temperature and decrease in air velocity led to decrease in quality of dried olive pomace. Keywords: Waste valorization, 2-phase olive pomace, Tray dryer, Energy efficiency, oxidation stability  

scholarly journals Design and Thermal Analysis of an Air Source Heat Pump Dryer for Food Drying

2018 ◽  
Vol 10 (9) ◽  
pp. 3216 ◽  
Author(s):  
Haolu Liu ◽  
Khurram Yousaf ◽  
Kunjie Chen ◽  
Rui Fan ◽  
Jiaxin Liu ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Moisture Content ◽  
Ambient Temperature ◽  
Heat Pump ◽  
Initial Moisture Content ◽  
Extraction Rate ◽  
Experimental Heat ◽  
Moisture Extraction ◽  
Temperature And Humidity ◽  
Heat Pump Drying

In this study, an experimental heat pump dryer was designed. The specific moisture extraction rate and moisture extraction rate were used as performance indicators to explore the influence of environmental factors and the style of the hot air cycle on heat pump drying. The average temperature and humidity in Nanjing’s summer, winter, and throughout the whole year were taken as the experimental ambient temperature and humidity. Garlic slices 3 mm thick, with an initial moisture content of 66.714% w.b., were dried until the end moisture content was 10% w.b. Experimental results and thermal analysis showed that the open and semi-open heat pump dryers were greatly affected by ambient temperature and humidity. The closed heat pump drying system was greatly affected by the bypass air rate.

scholarly journals Comparative investigation of performance of gas dryer and two other types of domestic clothes dryers

2020 ◽  
Author(s):  
Xiao-Mei Huang ◽  
Lian-Sen Xiong ◽  
Yan-Wen Zheng ◽  
Hui-Qing Liu ◽  
Yi-Zhen Xu ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Ambient Temperature ◽  
Heat Pump ◽  
Thermal Energy ◽  
Dry Mass ◽  
Primary Energy ◽  
Comparative Investigation ◽  
Ambient Temperatures ◽  
Moisture Extraction

Abstract The moisture extraction rate (MER) and energy efficiency of domestic gas clothes dryers, heat-pump clothes dryers and electric clothes dryers were assessed. The assessment was performed with regard to five indices: the MER, specific MER, specific thermal energy consumption for dehumidification (mSPC), energy efficiency (ηt) and primary energy efficiency (η1). The effects of the dry mass of clothes (mBD) and the ambient temperature on the performance of the clothes dryers were evaluated. The experiments were divided into two parts. In the first part, the ambient temperature was 20°C, and mBD was set as 1.5, 2.5, 3.5, 4.5 and 6 kg. In the second part, mBD was 3.5 kg, and the performance of the dryers was tested at ambient temperatures of 5, 7.5, 10, 12.5, 15 and 20°C. The experimental results indicated that the gas dryer had the highest MER the heat-pump dryer had the best performance with regard to energy conservation and all three types of dryers had a higher MER and energy efficiency when the ambient temperature increased. The performance of the gas dryer was lower than that of heat-pump dryer when the temperature was 20°C. But when the temperature was < 9.5°C, the primary energy efficiency of the gas dryer was higher than that of the heat-pump dryer.

scholarly journals An Economic Analysis of Rewind, Premium, and Standard Efficiency Vertical Hollow Shaft Motors for Irrigation

2020 ◽  
Vol 36 (2) ◽  
pp. 115-123
Author(s):  
Christopher G. Henry ◽  
Kenton B. Watkins ◽  
Ranjitsinh U. Mane ◽  
Gregory L. Stark
Keyword(s):  
Energy Efficiency ◽  
Economic Analysis ◽  
Energy Efficient ◽  
Net Present Value ◽  
Cost Effective ◽  
Payback Period ◽  
Department Of Energy ◽  
Present Value ◽  
Hollow Shaft ◽  
Capital Costs

Abstract. Vertical hollow shaft motors are commonly used for vertical turbine pumps for irrigation. They are a specialty motor which has been exempt from the Department of Energy (DOE) requirement for improved energy efficiency. We evaluated the payback and net present value (NPV) of standard efficiency, energy efficient, and premium efficiency motors for motor sizes used in irrigation. For motor sizes between 22 and 56 kW (30 and 75 hp), the NPV and payback analysis indicated that premium efficient motors are more advantageous than standard efficiency. In motor sizes greater than 75 kW (100 hp) standard efficient motors are more cost effective than replacing a motor with a premium efficiency motor. When considering a repair or rewind of a motor, the result is highly dependent on the quality, and the resulting efficiency expected after the repair. If a repaired motor nameplate efficiency could be attained after rewinding and repair, then rewinding is most cost effective. However, if original nameplate efficiency is not attained, then it may be more cost effective to purchase a premium efficiency motor over rewinding. New DOE requirements may be advantageous for irrigators even though capital costs will be higher for new motors. Keywords: Motor rewind, Net present value (NPV), Payback period, Premium efficiency motor.

scholarly journals Studies on drying characteristics and techno-economic analysis of sprouted moth beans (Vigna aconitifolia) in solar tunnel dryer

2019 ◽  
Author(s):  
C. M Badgujar ◽  
O. S. Karpe ◽  
S. R. Kalbande
Keyword(s):  
Moisture Content ◽  
Economic Analysis ◽  
Initial Moisture Content ◽  
Cost Benefit ◽  
Maximum Temperature ◽  
Drying Time ◽  
Sun Drying ◽  
Tunnel Dryer ◽  
Present Worth ◽  
Drying Efficiency

A commercial solar tunnel dryer (STD) was evaluated for drying of sprouted moth beans and also its techno-economic analysis was carried out. The maximum temperature 58ºC was recorded at 13:00h in STD during the drying process i.e. 41.0% (34.2ºC) higher than the maximum ambient temperature at the same time. A total drying time of 13:50h were required in STD to reduce the initial moisture content from 177.7% dry basis (d.b) to a final moisture content of 16.6% (d.b). However, the open sun drying took 16.5 drying hours to obtain desired moisture content. The net present worth and cost-benefit ratio of dryer was Rs.5,83,910.68/- and 1.19, respectively. However, the payback period for STD was 15 month 8 days. The cost economics of dried products were proved better for STD than open sun drying method. STD samples were found to be of good quality in terms of color, taste and aroma as compared to open sun dried (OSD) with an overall drying efficiency of STD was 19.7%. Therefore, the evaluated solar tunnel dryer were recommended for the drying of sprouted moth beans.

scholarly journals Heat pump drying of industrial wastewater sludge

2020 ◽  
Vol 15 (2) ◽  
pp. 404-415
Author(s):  
Gang Yuan ◽  
Khim Hoong Chu
Keyword(s):  
Heat Pump ◽  
Industrial Wastewater ◽  
Closed Loop ◽  
Energy Savings ◽  
Specific Energy Consumption ◽  
Extraction Rate ◽  
Wastewater Sludge ◽  
Loop Layout ◽  
Moisture Extraction ◽  
Exhaust Treatment

Abstract The popularity of heat drying of wastewater sludge has increased over the past several years because it can reduce sludge mass and volume, and hence disposal costs. However, drying sludge using conventional combustion-heated dryers is energy-intensive. Heat pump dryers can be efficient and offer significant energy savings by recycling the drying heat. This paper describes a heat pump dryer designed for continuous drying of industrial wastewater sludge. The dryer constructed was essentially a closed-loop air system. The air used for drying is dehumidified to recover the latent heat of vaporization, re-heated using the recovered heat, and recirculated in a closed environment. The closed-loop layout eliminates emissions of dust, malodorous gases, and volatile compounds, obviating the need for exhaust treatment otherwise required to meet environmental regulations. Data on the moisture extraction rate, specific moisture extraction rate, and specific energy consumption are presented and discussed.

Solar-Assisted Heat Pump Drying of Coriander: An Experimental Investigation

2018 ◽  
Vol 26 (04) ◽  
pp. 1850037 ◽  
Author(s):  
Abbas Alishah ◽  
Mohammad Valizadeh Kiamahalleh ◽  
Fereshteh Yousefi ◽  
Anita Emami ◽  
Meisam Valizadeh Kiamahalleh
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Solar Collector ◽  
Coefficient Of Performance ◽  
Air Flow Rate ◽  
Drying Time ◽  
Air Temperatures ◽  
Moisture Extraction ◽  
Heat Pump Drying ◽  
Time And Energy

In this study, the solar-assisted heat pump dryer was designed, manufactured, tested and optimized for drying operations of coriander for its preservation. The heat of drying was mainly provided by a solar collector and a heat pump with two experimental modes of turned on and off. The air temperatures and velocity were identified as the critical drying variables. The responses of the experiments were evaluated in terms of coefficient of performance (COP), energy consumption and the specific moisture extraction rate (SMER). Dehumidification of coriander from the moisture contents of 0.9 to 0.1 kg/kg was considerable. The results demonstrated that utilizing heat pump noticeably decreases the drying time (down to [Formula: see text]25%), energy consumption (down to [Formula: see text]12%) and increases SMER (up to [Formula: see text]20%). The increasing of air flow rate and air temperature significantly led to decreasing the drying time and energy consumption, however, increasing the COP and SMER.

scholarly journals Experimental Assessment of the Thermal Performance of a Heat Pump Dryer System Based on the Variations in Compressor Discharge Pressure on Oregano Drying

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6333
Author(s):  
Arley Salazar-Hincapié ◽  
Alvaro Delgado-Mejía ◽  
Andrés Felipe Romero-Maya ◽  
Eduardo Duque-Grisales
Keyword(s):  
Heat Pump ◽  
Coefficient Of Performance ◽  
Drying Time ◽  
Drying Temperature ◽  
Baseline Case ◽  
Moisture Extraction ◽  
Drying System ◽  
Heat Pump Drying ◽  
Discharge Pressure ◽  
Time And Energy

The current study shows an empirical analysis to establish the effects of the variations in compressor discharge pressure on the drying performance of aromatic herbs, in terms of the coefficient of performance (CoP), moisture content (MC), specific moisture extraction rate (SMER), drying temperature, drying time and energy consumption. In conducting the research, a heat pump drying system was utilized as a mechanism for dehydrating herbs, seeds, and fruits. It was used thanks to its benefits like higher efficiency and its low power consumption. Three levels of discharge pressure were considered, 1380 kPa, 1100 kPa, and 827 kPa, using 1,1,1,2-tetrafluoroethane (R134a) as a refrigerant and oregano leaves as the main product. The findings show that, concerning the same oregano moisture sample, the lower the compressor discharge pressure, the lower drying temperature, also, the higher drying time was obtained. Despite the fact that the CoP decreased with the compressor discharge pressure, in comparison with the baseline case, it remained essentially the same for the other two cases.

scholarly journals Experimental Analysis of a Heat Pump Dryer with an External Desiccant Wheel Dryer

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1216
Author(s):  
Kai-Shing Yang ◽  
Khalid Hamid ◽  
Shih-Kuo Wu ◽  
Uzair Sajjad ◽  
Chi-Chuan Wang
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Rate ◽  
Heat Pump ◽  
Transfer Rate ◽  
Extraction Rate ◽  
Pump System ◽  
Test Load ◽  
Desiccant Wheel ◽  
Moisture Extraction ◽  
Lower Test

This study examines the performance of three heat pump dryers: the original reference design, a modified drying chamber, and an external desiccant wheel design. Unlike most existing studies that normally adopt organic products as the drying materials, in this study we used moist sodium polyacrylate (Orbeez) as the drying material for consistent characterization of the heat pump performance. R-134a was adopted as the refrigerant for the heat pump system. The experiments were performed subject to different weights of Orbeez (drying material) at a constant volumetric flow rate of 100 m3/h. During experimentation, different parameters like the coefficient of performance (COPHP), drying rate, heat transfer rate by the condenser, moisture extraction rate, and specific moisture extraction rate were calculated. The average COPHP, mass transfer rate, heat transfer rate, MER, and SMER of the system were calculated as 3.9, 0.30 kg/s, 0.56 kW, 0.495 kg/h, and 1.614 kg/kWh, respectively. The maximum COP for the refrigeration system was achieved at lower test loads with the desiccant wheel. The moisture extraction rate for a lower test loading was higher than that for a higher test load due to the higher penetration of drying air at the lower test load, although the maximum test load showed the maximum relative humidity at the dryer outlet. The desiccant wheel showed good performance in terms of moisture extraction rate and COPHP, but it showed poor performance in terms of the specific moisture extraction rate due to the high power consumption (around 2.6 kW) of the desiccant dehumidifier. The moisture extraction rate (MER) for all designs increased to a maximum value, followed by consistent decline. However, the maximum MER for the desiccant design exceeded those for the other designs.

Sign in / Sign up

Export Citation Format

Share Document