scholarly journals Comparative performance of a solar assisted heat pump dryer with a heat pump dryer for Curcuma

2020 ◽  
Vol 11 (3) ◽  
pp. 1617
Author(s):  
R. Hasibuan ◽  
M Yahya ◽  
H. Fahmi ◽  
Edison Edison
Keyword(s):  
Heat Pump ◽  
Specific Energy Consumption ◽  
Coefficient Of Performance ◽  
Drying Rate ◽  
Comparative Performance ◽  
Drying Time ◽  
Air Mass ◽  
Average Temperature ◽  
Moisture Extraction ◽  
Curcuma Xanthorrhiza

<p>This study evaluated the performances of solar assisted heat pump dryer (SAHPD) and heat pump dryer (HPD) for drying of <em>Curcuma xanthorrhiza Roxb</em>. The HPD and SAHPD reduced mass of <em>Curcuma</em> from 30.70 kg to 7.85 kg needed 10.5 hours and 8 hours with average temperature and relative humidity 49.2oC and 26.5%, and 57.7oC and 19.8%, for SD and SAHPD respectively. The moisture of Curcuma dried from 3.167 db to 0.065 db with an air mass flow rate of 0.121 kg/s. The SAHPD reduced the drying time about 24% compared to HPD. The drying rate and the specific energy consumption were calculated in an average 1.05 kg/h and 1.36kg/h, and 1.17kWh/kg and 2.07kWh/kg for HPD and SAHPD, respectively. The specific moisture extraction rate and the dryer thermal efficiency were calculated in an average 0.931 kg/kWh and 0.521 kg/kWh, and 61.0% and 34.3% for HPD and SAHPD, respectively. Whereas, the pickup efficiency and the coefficient of performance of the heat pump were calculated in an average 57.5% and 59.2%, and 4.03and 4.35 for HPD and SAHPD, respectively. The SAHPD is capable of drying <em>Curcuma</em> quickly because of the high pickup efficiency and high drying rate.</p>

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 Performance Analysis of Solar Assisted Fluidized Bed Dryer Integrated Biomass Furnace with and without Heat Pump for Drying of Paddy

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
M. Yahya
Keyword(s):  
Moisture Content ◽  
Fluidized Bed ◽  
Heat Pump ◽  
Specific Energy Consumption ◽  
Drying Rate ◽  
Fluidized Bed Dryer ◽  
Moisture Extraction ◽  
Rate Period ◽  
Drying Behaviour ◽  
Kinetics Of

The performances of a solar assisted fluidized bed dryer integrated biomass furnace (SA-FBDIBF) and a solar assisted heat pump fluidized bed dryer integrated biomass furnace (SAHP-FBDIBF) for drying of paddy have been evaluated, and also drying kinetics of paddy were determined. The SA-FBDIBF and the SAHP-FBDIBF were used to dry paddy from 11 kg with moisture content of 32.85% db to moisture content of 16.29% db (14% wb) under an air mass flow rate of 0.1037 kg/s within 29.73 minutes and 22.95 minutes, with average temperatures and relative humidities of 80.3°C and 80.9°C and 12.28% and 8.14%, respectively. The average drying rate, specific energy consumption, and specific moisture extraction rate were 0.043 kg/minute and 0.050 kg/minute, 5.454 kWh/kg and 4.763 kWh/kg, and 0.204 kg/kWh and 0.241 kg/kWh for SA-FBDIBF and SAHP-FBDIBF, respectively. In SA-FBDIBF and SAHP-FBDIBF, the dryer thermal efficiencies were average values of 12.28% and 15.44%; in addition, the pickup efficiencies were 33.55% and 43.84% on average, whereas the average solar and biomass fractions were 10.9% and 10.6% and 36.6% and 30.4% for SA-FBDIBF and SAHP-FBDIBF, respectively. The drying of paddy occurred in the falling rate period. The experimental dimensionless moisture content data were fitted to three mathematical models. Page’s model was found best to describe the drying behaviour of paddy.

scholarly journals Performance of a Heat Pump Dehumidifier Dryer

1997 ◽  
Author(s):  
S. Wongwises ◽  
T. Yoovidhaya ◽  
P. Supontana ◽  
W. Kaensup
Keyword(s):  
Heat Pump ◽  
Coefficient Of Performance ◽  
Optimum Operating ◽  
Drying Rate ◽  
Shiitake Mushroom ◽  
Optimum Operating Condition ◽  
Moisture Extraction ◽  
Maximum Coefficient ◽  
Drying Rates ◽  
Key Parameter

In the present study, a heat pump dryer was designed and constructed. The performance of a heat pump assisted dryer was studied. The system was operated by using R22. The experimental data of the drying rates of shiitake mushroom was used to predict the specific moisture extraction rates (SMER). The maximum coefficient of performance (COP) of heat pump was also specified. The optimum operating condition was determined by the percentage of air recirculation from the total air mass flow rate. Finally, the key parameter that influence on the performance of the system and drying rate were specified.

scholarly journals Performance Analysis of Heat Pump Dryer with Unit-Room in Cold Climate Regions

Energies ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 3125 ◽  
Author(s):  
Yuan ◽  
Lin ◽  
Mao ◽  
Li ◽  
Yang ◽  
...  
Keyword(s):  
Heat Pump ◽  
Ambient Air ◽  
Open Loop ◽  
Cold Climate ◽  
Coefficient Of Performance ◽  
Ambient Conditions ◽  
Total Energy Consumption ◽  
Ambient Temperatures ◽  
Moisture Extraction ◽  
Modelling System

This study presents the development and evaluation of a novel partially open-loop heat pump dryer with a unit-room (HPDU). The unit-room was designed to enable the ambient air to be mixed with the return air, thereby reducing the influence of the ambient air on the system performance, while maintaining a high system thermal efficiency. A modelling system for the HPDU was developed and validated based on a real-scale experimental study. By using the modelling system, the system characteristics under different ambient conditions and bypass factors were analyzed. The energy benefit of the proposed HPDU was quantified through a comparative study with a closed-loop heat pump dryer (CHPD). It is evident that a maximal specific moisture extraction rate (SMER) and a minimal total energy consumption (TEC) existed when changing the bypass factor of the HPDU under certain ambient temperatures. Compared to the CHPD, the coefficient of performance (COP) of the HPDU increased by up to 39.56%, presenting a significant energy benefit for the application of HPDU.

An Investigation of Energy Consumption, Solar Fraction and Hybrid Photovoltaic–Thermal Solar Dryer Parameters in Drying of Chamomile Flower

2014 ◽  
Vol 10 (4) ◽  
pp. 697-711 ◽  
Author(s):  
Saeid Minaei ◽  
Ali Motevali ◽  
Barat Ghobadian ◽  
Ahmad Banakar ◽  
Seyed Hashem Samadi
Keyword(s):  
Energy Consumption ◽  
Heat Pump ◽  
Air Temperature ◽  
Coefficient Of Performance ◽  
Pump Mode ◽  
Energy Fraction ◽  
Drying Time ◽  
Solar Dryer ◽  
Drying Behavior ◽  
Chamomile Flower

Abstract In this research, drying of a medicinal plant (chamomile) in a hybrid photovoltaic–thermal solar dryer with and without heat pump was investigated. The experiments were performed at three air speeds (0.5, 1, and 1.5 m/s), three levels of air temperature (40, 50, and 60°C), with and without using a heat pump. Results of analysis indicated that adding a heat pump to the photovoltaic solar dryer decreases drying time, energy consumption, and required specific energy. Solar energy fraction increased with decreasing air temperature and velocity. Analysis of the dryer-related parameters showed that the maximum and minimum thermal efficiencies were 33.8 and 16.4%, respectively, both in the no-heat-pump mode while with the heat pump, its maximum and minimum values were 38.4 and 19.7%, respectively. Moreover, the highest and lowest electrical efficiencies for the no-heat-pump mode were 13.4 and 9.1%, respectively; while using the heat pump, its maximum and minimum values were 14.1 and 10.4%, respectively. Results of analyzing the dryer’s coefficient of performance for drying chamomile showed that the highest and lowest coefficients of performance were 3.41 and 1.82, respectively. Eleven mathematical models were tested, and Page’s model was selected as the best for describing the drying behavior of chamomile flower.

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.

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.

Analysis of a Solar Assisted Heat Pump Dryer With a Storage Tank

Solar Energy ◽  
2006 ◽  
Author(s):  
Yingbai Xie ◽  
Leina Song ◽  
Chuntao Liu
Keyword(s):  
Energy Storage ◽  
Heat Pump ◽  
Storage Tank ◽  
Weather Conditions ◽  
Coefficient Of Performance ◽  
Drying Time ◽  
Energy Inputs ◽  
Drying System ◽  
Typical Summer ◽  
Agriculture Products

In north china, agriculture products may be harvested above safe storage moistures to prevent excessive field losses. A solar-assisted heat pump drying system (SAHP) with an energy storage tank has been proposed to meet the demand in this field. The drying system is designed in such a way that some of the components can be isolated depending on the weather conditions and usage pattern. The performance of the whole system has been modeled and investigated under a typical summer day of the city Baoding, China. Results show that the coefficient of performance (COP) of the SAHP drying system is 5.369, while it is 3.411 without solar energy inputs. With an energy storage tank, the SAHP drying system performs more stable and modulates the mismatch between solar radiation and the energy needed in the night. Other discussions on collector numbers, drying time and drying temperature are also processed, which will be helpful to apply the system in China.

scholarly journals Determination of coefficient of performance of mechanical vapour recompression heat pump

2019 ◽  
Vol 112 ◽  
pp. 01013
Author(s):  
Slav Valchev ◽  
Nenko Nenov ◽  
Vasil Georgiev
Keyword(s):  
Wastewater Treatment ◽  
Water Vapour ◽  
Heat Pump ◽  
Compression Ratio ◽  
Wastewater Treatment Plants ◽  
Specific Energy Consumption ◽  
Coefficient Of Performance ◽  
Pump System ◽  
Heat Pump System

Mechanical vapour recompression heat pump systems are widely used in the industry -in evaporator and distillation installations, in seawater desalination and industrial wastewater treatment plants. The estimation of the energy efficiency level of this type of system is based on values of two basic parameters: specific energy consumption for production of 1 kg clean water (condensate) and actual coefficient of performance of heat pump system. The object of study is experimental determination of value of actual coefficient of performance of mechanical vapour recompression heat pump system for wastewater treatment. A mathematical regression equation between the actual coefficient of performance μ and two significant factors – temperature of secondary water vapour tsv and compression ratio of water vapour in mechanical compressor of heat pump system σ is received. The analysis show that actual coefficient of performance μ highly depends of value of compression ratio σ and less depends of values of temperature of secondary vapour tsv. It conclude that MVR heat pump system, in order to operate with high values of the actual coefficient of performance should be working to high values of temperature of secondary vapour and low values of compression ratio of water vapour in mechanical compressor.

Sign in / Sign up

Export Citation Format

Share Document