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Energy Systems and Applications in Agriculture

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "B: Energy and Environment".

Deadline for manuscript submissions: closed (30 June 2022) | Viewed by 35554

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Guest Editor
Department of Biological and Agricultural Engineering, University of California, Davis, CA 95616, USA
Interests: thermal environment modeling; energy-efficient design; renewable energy-based operation of controlled environment agricultural (CEA) production facilities
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Guest Editor

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Guest Editor
Mechanical and Construction Engineering Department, University of Northumbria, Newcastle Upon Tyne NE1 8ST, UK
Interests: water treatment; cooling; energy storage; renewables; thermodynamics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Agriculture, as a production-oriented sector, entails energy as a substantial input by which global food security is ensured. Agricultural systems use energy either directly as fuel or electricity to operate machinery and equipment, heating, ventilation, and air-conditioning (HVAC) of agricultural built environments, lighting, food transportation, preservation, or indirectly in the fertilizers and chemicals produced off the farm. Increasing agriculture modernization/mechanization mitigates conventional energy reserves, which also escalates greenhouse gas emissions (GHG) and climate change. Therefore, it is important to develop energy-efficient and environmentally friendly solutions for the agriculture sector to achieve the 2030 UN Sustainable Development Goals. Various energy systems and technologies are involved/needed in the agricultural practices/applications that include (but are not limited to) sowing and seedbed preparation; tillage operations and cultivations; spraying and harvesting; post-harvest processing and value addition; livestock/dairy and poultry barns; indoor farming  and aquaponics agriculture; sprinkler and drip irrigation systems. Conventionally, these agricultural systems and their operations are heavily dependent on fossil fuel-based energy sources, which are inefficient, expensive, and responsible for GHG emissions. Therefore, this Special Issue aims to showcase recent advancements and improvements of such energy systems and their technologies for various agricultural practices/applications. This Special Issue will consider cutting-edge research works and review articles focused on energy-efficient system design, integration of renewable energy, automation, and control, modeling and simulation, energy-efficient post-harvest processing, and alternate energy sources for the agricultural production systems.

Prof. Dr. Muhammad Sultan
Prof. Dr. Md Shamim Ahamed
Dr. Redmond R. Shamshiri
Prof. Dr. Muhammad Wakil Shahzad
Guest Editors

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Keywords

  • Energy-efficient agriculture
  • Robotics and farm mechanization
  • Food processing and storage
  • Renewable energy for agriculture
  • Temperature and humidity control systems for agriculture
  • Sustainable energy and clean fuel for farmers
  • Biomass, biogas, and bioenergy
  • Next-generation greenhouses
  • Aquaponics, hydroponic and aeroponic farming
  • Sprinkler and drip irrigation systems
  • Solar dryers and solar pumping
  • Livestock and poultry barns
  • Agricultural built environment
  • Modeling and simulation
  • Modern water/wastewater treatment

Published Papers (12 papers)

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Editorial

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3 pages, 173 KiB  
Editorial
Energy Systems and Applications in Agriculture
by Muhammad Sultan, Muhammad Hamid Mahmood, Md Shamim Ahamed, Redmond R. Shamshiri and Muhammad Wakil Shahzad
Energies 2022, 15(23), 9132; https://doi.org/10.3390/en15239132 - 2 Dec 2022
Viewed by 1238
Abstract
Agriculture and agro-based industries consume more energy, mainly derived from fossil fuels [...] Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)

Research

Jump to: Editorial

13 pages, 3103 KiB  
Article
Effect of Operating Parameters and Energy Expenditure on the Biological Performance of Rotating Biological Contactor for Wastewater Treatment
by Muhammad Irfan, Sharjeel Waqas, Javed Akbar Khan, Saifur Rahman, Izabela Kruszelnicka, Dobrochna Ginter-Kramarczyk, Stanislaw Legutko, Marek Ochowiak, Sylwia Włodarczak and Krystian Czernek
Energies 2022, 15(10), 3523; https://doi.org/10.3390/en15103523 - 11 May 2022
Cited by 8 | Viewed by 2373
Abstract
The rotating biological contactor (RBC) is resistant to toxic chemical and shock loadings, and this results in significant organic and nutrient removal efficiencies. The RBC system offers a low-energy footprint and saves up to 90% in energy costs. Due to the system’s low-energy [...] Read more.
The rotating biological contactor (RBC) is resistant to toxic chemical and shock loadings, and this results in significant organic and nutrient removal efficiencies. The RBC system offers a low-energy footprint and saves up to 90% in energy costs. Due to the system’s low-energy demand, it is easily operable with renewable energy sources, either solar or wind power. An RBC was employed to degrade pollutants in domestic wastewater through biodegradation mechanisms in this study. The high microbial population in the RBC bioreactor produced excellent biological treatment capacity and higher effluent quality. The results showed that the RBC bioreactor achieved an average removal efficiency of 73.9% of chemical oxygen demand (COD), 38.3% of total nitrogen (TN), 95.6% of ammonium, and 78.9% of turbidity. Investigation of operational parameters, disk rotational speed, HRT, and SRT, showed the biological performance impact. Disk rotational speed showed uniform effluent quality at 30–40 rpm, while higher values of disk rotational speed (>40 rpm) resulted in lower effluent quality in COD, TN, and turbidity. The longer hydraulic retention time and sludge retention time (SRT) facilitated higher biological performance efficiency. The longer SRTs enabled the higher TN removal efficiency because of the higher quantity of microbial biomass retention. The longer SRT also resulted in efficient sludge-settling properties and reduced volume of sludge production. The energy evaluation of the RBC bioreactor showed that it consumed only 0.14 kWh/m3, which is significantly lower than the conventional treatment methods; therefore, it is easily operable with renewable energy sources. The RBC is promising substitute for traditional suspended growth processes as higher microbial activity, lower operational and maintenance costs, and lower carbon foot print enhanced the biological performance, which aligns with the stipulations of ecological evolution and environment-friendly treatment. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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23 pages, 7425 KiB  
Article
Potential Investigation of Membrane Energy Recovery Ventilators for the Management of Building Air-Conditioning Loads
by Hadeed Ashraf, Muhammad Sultan, Uzair Sajjad, Muhammad Wakil Shahzad, Muhammad Farooq, Sobhy M. Ibrahim, Muhammad Usman Khan and Muhammad Ahmad Jamil
Energies 2022, 15(6), 2139; https://doi.org/10.3390/en15062139 - 15 Mar 2022
Cited by 4 | Viewed by 2405
Abstract
The present study provides insights into the energy-saving potential of a membrane energy recovery ventilator (ERV) for the management of building air-conditioning loads. This study explores direct (DEC), Maisotsenko cycle (MEC) evaporative cooling, and vapor compression (VAC) systems with ERV. Therefore, this study [...] Read more.
The present study provides insights into the energy-saving potential of a membrane energy recovery ventilator (ERV) for the management of building air-conditioning loads. This study explores direct (DEC), Maisotsenko cycle (MEC) evaporative cooling, and vapor compression (VAC) systems with ERV. Therefore, this study aims to explore possible air-conditioning options in terms of temperature, relative humidity, human thermal comfort, wet bulb effectiveness, energy saving potential, and CO2 emissions. Eight different combinations of the above-mentioned systems are proposed in this study i.e., DEC, MEC, VAC, MEC-VAC, and their possible combinations with and without ERVs. A building was modeled in DesignBuilder and simulated in EnergyPlus. The MEC-VAC system with ERV achieved the highest temperature gradient, wet bulb effectiveness, energy-saving potential, optimum relative humidity, and relatively lower CO2 emissions i.e., 19.7 °C, 2.2, 49%, 48%, and 499.2 kgCO2/kWh, respectively. Thus, this study concludes the hybrid MEC-VAC system with ERV the optimum system for the management of building air-conditioning loads. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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18 pages, 3868 KiB  
Article
Assessment of Wind and Solar Hybrid Energy for Agricultural Applications in Sudan
by Zafar A. Khan, Muhammad Imran, Abdullah Altamimi, Ogheneruona E. Diemuodeke and Amged Osman Abdelatif
Energies 2022, 15(1), 5; https://doi.org/10.3390/en15010005 - 21 Dec 2021
Cited by 21 | Viewed by 3724
Abstract
In addition to zero-carbon generation, the plummeting cost of renewable energy sources (RES) is enabling the increased use of distributed-generation sources. Although the RES appear to be a cheaper source of energy, without the appropriate design of the RES with a true understanding [...] Read more.
In addition to zero-carbon generation, the plummeting cost of renewable energy sources (RES) is enabling the increased use of distributed-generation sources. Although the RES appear to be a cheaper source of energy, without the appropriate design of the RES with a true understanding of the nature of the load, they can be an unreliable and expensive source of energy. Limited research has been aimed at designing small-scale hybrid energy systems for irrigation pumping systems, and these studies did not quantify the water requirement, or in turn the energy required to supply the irrigation water. This paper provides a comprehensive feasibility analysis of an off-grid hybrid renewable energy system for the design of a water-pumping system for irrigation applications in Sudan. A systematic and holistic framework combined with a techno-economic optimization analysis for the planning and design of hybrid renewable energy systems for small-scale irrigation water-pumping systems is presented. Different hybridization cases of solar photovoltaic, wind turbine and battery storage at 12 different sites in Sudan are simulated, evaluated, and compared, considering the crop water requirement for different crops, the borehole depth, and the stochasticity of renewable energy resources. Soil, weather, and climatic data from 12 different sites in Sudan were used for the case studies, with the key aim to find the most robust and reliable solution with the lowest system cost. The results of the case studies suggest that the selection of the system is highly dependent on the cost, the volatility of the wind speed, solar radiation, and the size of the system; at present, hybridization is not the primary option at most of sites, with the exception of two. However, with the reduction in price of wind technology, the possibility of hybrid generation will rise. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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23 pages, 34518 KiB  
Article
Assessing Crop Water Requirements and a Case for Renewable-Energy-Powered Pumping System for Wheat, Cotton, and Sorghum Crops in Sudan
by Zafar A. Khan, Muhammad Imran, Jamal Umer, Saeed Ahmed, Ogheneruona E. Diemuodeke and Amged Osman Abdelatif
Energies 2021, 14(23), 8133; https://doi.org/10.3390/en14238133 - 4 Dec 2021
Cited by 9 | Viewed by 2334
Abstract
Climate change is changing global weather patterns, with an increase in droughts expected to impact crop yields due to water scarcity. Crops can be provided with water via underground pumping systems to mitigate water shortages. However, the energy required to pump water tends [...] Read more.
Climate change is changing global weather patterns, with an increase in droughts expected to impact crop yields due to water scarcity. Crops can be provided with water via underground pumping systems to mitigate water shortages. However, the energy required to pump water tends to be expensive and hazardous to the environment. This paper explores different sites in Sudan to assess the crop water requirements as the first stage of developing renewable energy sources based on water pumping systems. The crop water requirements are calculated for different crops using the CROPWAT and CLIMWAT simulation tools from the Food and Agriculture Organization (FAO) of the United Nations. Further, the crop water requirements are translated into electrical energy requirements. Accurate calculations of the energy needed will help in developing cost-effective energy systems that can help in improving yields and reducing carbon emissions. The results suggest that the northern regions tend to have higher energy demands and that the potential for renewable energy should be explored in these regions, which are more susceptible to drought and where crops tend to be under higher stress due to adverse climate conditions. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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20 pages, 7556 KiB  
Article
Solar-Hybrid Cold Energy Storage System Coupled with Cooling Pads Backup: A Step towards Decentralized Storage of Perishables
by Anjum Munir, Tallha Ashraf, Waseem Amjad, Abdul Ghafoor, Sidrah Rehman, Aman Ullah Malik, Oliver Hensel, Muhammad Sultan and Tatiana Morosuk
Energies 2021, 14(22), 7633; https://doi.org/10.3390/en14227633 - 15 Nov 2021
Cited by 7 | Viewed by 4028
Abstract
Post-harvest loss is a serious issue to address challenge of food security. A solar-grid hybrid cold storage system was developed and designed for on-farm preservation of perishables. Computational Fluid Dynamic analysis was performed to assess airflow and temperature distribution inside the cold chamber. [...] Read more.
Post-harvest loss is a serious issue to address challenge of food security. A solar-grid hybrid cold storage system was developed and designed for on-farm preservation of perishables. Computational Fluid Dynamic analysis was performed to assess airflow and temperature distribution inside the cold chamber. The system comprises a 21.84 m3 cubical cold storage unit with storage capacity of 2 tonnes. A hybrid solar system comprising 4.5 kWp PV system, 5 kW hybrid inverter, and 600 Ah battery bank was used to power the entire system. A vapor-compression refrigeration system (2 tonnes) was employed coupled with three cooling pads (filled with brine solution) as thermal backup to store cooling (−4 °C to 4 °C). Potatoes were stored at 8 °C for a period of three months (May 2019 to July 2019) and the system was tested on grid utility, solar, and hybrid modes. Solar irradiation was recorded in range of 5.0–6.0 kWh/(m2 × d) and average power peak was found to be 4.0 kW. Variable frequency drive was installed with compressor to eliminate the torque load and it resulted about 9.3 A AC current used by the system with 4.6 average Coefficient of Performance of refrigeration unit. The average energy consumed by system was found to be 15 kWh with a share of 4.3 kWh from grid and 10.5 kWh from solar, translating to 30% of power consumption from grid and 70% from solar PV modules. Overall, cold storage unit efficiently controlled total weight loss (7.64%) and preserved quality attributes (3.6 ⁰Brix Total soluble solids, 0.83% Titratable acidity, 6.32 PH) of the product during storage time. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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12 pages, 595 KiB  
Article
Techno-Economic Analysis of Fast Pyrolysis of Date Palm Waste for Adoption in Saudi Arabia
by Sulaiman Al Yahya, Tahir Iqbal, Muhammad Mubashar Omar and Munir Ahmad
Energies 2021, 14(19), 6048; https://doi.org/10.3390/en14196048 - 23 Sep 2021
Cited by 35 | Viewed by 3722
Abstract
Date palm trees, being an important source of nutrition, are grown at a large scale in Saudi Arabia. The biomass waste of date palm, discarded of in a non-environmentally-friendly manner at present, can be used for biofuel generation through the fast pyrolysis technique. [...] Read more.
Date palm trees, being an important source of nutrition, are grown at a large scale in Saudi Arabia. The biomass waste of date palm, discarded of in a non-environmentally-friendly manner at present, can be used for biofuel generation through the fast pyrolysis technique. This technique is considered viable for thermochemical conversion of solid biomass into biofuels in terms of the initial investment, production cost, and operational cost, as well as power consumption and thermal application cost. In this study, a techno-economic analysis has been performed to assess the feasibility of converting date palm waste into bio-oil, char, and burnable gases by defining the optimum reactor design and thermal profile. Previous studies concluded that at an optimum temperature of 525 °C, the maximum bio-oil, char and gases obtained from pyrolysis of date palm waste contributed 38.8, 37.2 and 24% of the used feed stock material (on weight basis), respectively, while fluidized bed reactor exhibited high suitability for fast pyrolysis. Based on the pyrolysis product percentage, the economic analysis estimated the net saving of USD 556.8 per ton of the date palm waste processed in the pyrolysis unit. It was further estimated that Saudi Arabia could earn USD 44.77 million per annum, approximately, if 50% of the total date palm waste were processed through fast pyrolysis, with a payback time of 2.57 years. Besides that, this intervention will reduce 2029 tons of greenhouse gas emissions annually, contributing towards a lower carbon footprint. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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19 pages, 5056 KiB  
Article
A Time-Dependent Model for Predicting Thermal Environment of Mono-Slope Solar Greenhouses in Cold Regions
by Shuyao Dong, Md Shamim Ahamed, Chengwei Ma and Huiqing Guo
Energies 2021, 14(18), 5956; https://doi.org/10.3390/en14185956 - 19 Sep 2021
Cited by 10 | Viewed by 2457
Abstract
Most greenhouses in the Canadian Prairies shut down during the coldest months (November to February) because of the hefty heating cost. Chinese mono-slope solar greenhouses do not primarily rely on supplemental heating; instead, they mostly rely on solar energy to maintain the required [...] Read more.
Most greenhouses in the Canadian Prairies shut down during the coldest months (November to February) because of the hefty heating cost. Chinese mono-slope solar greenhouses do not primarily rely on supplemental heating; instead, they mostly rely on solar energy to maintain the required indoor temperature in winter. This study focuses on improving an existing thermal model, entitled RGWSRHJ, for Chinese-style solar greenhouses (CSGs) to increase the robustness of the model for simulating the thermal environment of the CSGs located outside of China. The modified model, entitled SOGREEN, was validated using the field data collected from a CSG in Manitoba, Canada. The results indicate that the average prediction error for indoor and relative humidity is 1.9 °C and 7.0%, and the rRMSE value is 3.3% and 11.5%, respectively. The average error for predicting the north wall and ground surface temperature is 4.2 °C and 2.3 °C, respectively. The study also conducted a case study to analyze the thermal performance of a conceptual CSG in Saskatoon, Canada. The energy analysis indicates the heating requirement of the greenhouse highly depends on the availability of solar radiation. Besides winter, the heating requirement is relatively low in March to maintain 18 °C indoor temperature when the average outdoor temperature was below –4 °C, and negligible during May–August. The results indicate that vegetable production in CSGs could save about 55% on annual heating than traditional greenhouses. Hence, CSGs could be an energy-efficient solution for ensuring food security for northern communities in Canada and other cold regions. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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18 pages, 8817 KiB  
Article
Investigation of Energy Consumption and Associated CO2 Emissions for Wheat–Rice Crop Rotation Farming
by Muhammad N. Ashraf, Muhammad H. Mahmood, Muhammad Sultan, Redmond R. Shamshiri and Sobhy M. Ibrahim
Energies 2021, 14(16), 5094; https://doi.org/10.3390/en14165094 - 18 Aug 2021
Cited by 7 | Viewed by 1974
Abstract
This study investigates the input–output energy-flow patterns and CO2 emissions from the wheat–rice crop rotation system. In this regard, an arid region of Punjab, Pakistan was selected as the study area, comprising 4150 km2. Farmers were interviewed to collect data [...] Read more.
This study investigates the input–output energy-flow patterns and CO2 emissions from the wheat–rice crop rotation system. In this regard, an arid region of Punjab, Pakistan was selected as the study area, comprising 4150 km2. Farmers were interviewed to collect data and information on input/output sources during the 2020 work season. The total energy from these sources was calculated using appropriate energy equivalents. Three energy indices, including energy use efficiency (ηe), energy productivity (ηp), and net energy (ρ), were defined and calculated to investigate overall energy efficiency. Moreover, the data envelopment analysis (DEA) technique was used to optimize the input energy in wheat and rice production. Finally, CO2 emissions was calculated using emissions equivalents from peer-reviewed published literature. Results showed that the average total energy consumption in rice production was twice the energy consumed in wheat production. However, the values of ηe, ηp, and ρ were higher in wheat production and calculated as 5.68, 202.3 kg/GJ, and 100.12 GJ/ha, respectively. The DEA showed the highest reduction potential in machinery energy for both crops, calculated as −42.97% in rice production and −17.48% in wheat production. The highest CO2 emissions were found in rice production and calculated as 1762.5 kg-CO2/ha. Our conclusion indicates that energy consumption and CO2 emissions from wheat–rice cropping systems can be minimized using optimized energy inputs. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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19 pages, 1039 KiB  
Article
Exergy and Energy Analyses of Microwave Dryer for Cantaloupe Slice and Prediction of Thermodynamic Parameters Using ANN and ANFIS Algorithms
by Safoura Zadhossein, Yousef Abbaspour-Gilandeh, Mohammad Kaveh, Mariusz Szymanek, Esmail Khalife, Olusegun D. Samuel, Milad Amiri and Jacek Dziwulski
Energies 2021, 14(16), 4838; https://doi.org/10.3390/en14164838 - 9 Aug 2021
Cited by 18 | Viewed by 2520
Abstract
The study targeted towards drying of cantaloupe slices with various thicknesses in a microwave dryer. The experiments were carried out at three microwave powers of 180, 360, and 540 W and three thicknesses of 2, 4, and 6 mm for cantaloupe drying, and [...] Read more.
The study targeted towards drying of cantaloupe slices with various thicknesses in a microwave dryer. The experiments were carried out at three microwave powers of 180, 360, and 540 W and three thicknesses of 2, 4, and 6 mm for cantaloupe drying, and the weight variations were determined. Artificial neural networks (ANN) and adaptive neuro-fuzzy inference systems (ANFIS) were exploited to investigate energy and exergy indices of cantaloupe drying using various afore-mentioned input parameters. The results indicated that a rise in microwave power and a decline in sample thickness can significantly decrease the specific energy consumption (SEC), energy loss, exergy loss, and improvement potential (probability level of 5%). The mean SEC, energy efficiency, energy loss, thermal efficiency, dryer efficiency, exergy efficiency, exergy loss, improvement potential, and sustainability index ranged in 10.48–25.92 MJ/kg water, 16.11–47.24%, 2.65–11.24 MJ/kg water, 7.02–36.46%, 12.36–42.70%, 11.25–38.89%, 3–12.2 MJ/kg water, 1.88–10.83 MJ/kg water, and 1.12–1.63, respectively. Based on the results, the use of higher microwave powers for drying thinner samples can improve the thermodynamic performance of the process. The ANFIS model offers a more accurate forecast of energy and exergy indices of cantaloupe drying compare to ANN model. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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22 pages, 93522 KiB  
Article
Development and Validation of Air-to-Water Heat Pump Model for Greenhouse Heating
by Adnan Rasheed, Wook Ho Na, Jong Won Lee, Hyeon Tae Kim and Hyun Woo Lee
Energies 2021, 14(15), 4714; https://doi.org/10.3390/en14154714 - 3 Aug 2021
Cited by 10 | Viewed by 2985
Abstract
This study proposes a building energy simulation (BES) model of an air-to-water heat pump (AWHP) system integrated with a multi-span greenhouse using the TRNSYS-18 program. The proposed BES model was validated using an experimental AWHP and a multi-span greenhouse installed in Kyungpook National [...] Read more.
This study proposes a building energy simulation (BES) model of an air-to-water heat pump (AWHP) system integrated with a multi-span greenhouse using the TRNSYS-18 program. The proposed BES model was validated using an experimental AWHP and a multi-span greenhouse installed in Kyungpook National University, Daegu, South Korea (latitude 35.53° N, longitude 128.36° E, elevation 48 m). Three AWHPs and a water storage tank were used to fulfill the heat energy requirement of the three-span greenhouse with 391.6 m2 of floor area. The model was validated by comparing the following experimental and simulated results, namely, the internal greenhouse temperature, the heating load of the greenhouse, heat supply from the water storage tank to the greenhouse, heat pumps’ output water temperature, power used by the heat pumps, coefficient of performance (COP) of the heat pump, and water storage tank temperature. The BES model’s performance was evaluated by calculating the root mean square error (RMSE) and the Nash–Sutcliffe efficiency (NSE) coefficient of validation results. The overall results correlated well with the experimental and simulated results and encouraged adopting the BES model. The average calculated COP of the AWHP was 2.2 when the outside temperature was as low as −13 °C. The proposed model was designed simply, and detailed information of each step is provided to make it easy to use for engineers, researchers, and consultants. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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22 pages, 4899 KiB  
Article
Study on Adsorption Properties of Modified Corn Cob Activated Carbon for Mercury Ion
by Yuyingnan Liu, Xinrui Xu, Bin Qu, Xiaofeng Liu, Weiming Yi and Hongqiong Zhang
Energies 2021, 14(15), 4483; https://doi.org/10.3390/en14154483 - 24 Jul 2021
Cited by 23 | Viewed by 2995
Abstract
In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of [...] Read more.
In this study, corn cob was used as raw material and modified methods employing KOH and KMnO4 were used to prepare activated carbon with high adsorption capacity for mercury ions. Experiments on the effects of different influencing factors on the adsorption of mercury ions were undertaken. The results showed that when modified with KOH, the optimal adsorption time was 120 min, the optimum pH was 4; when modified with KMnO4, the optimal adsorption time was 60 min, the optimal pH was 3, and the optimal amount of adsorbent and the initial concentration were both 0.40 g/L and 100 mg/L under both modified conditions. The adsorption process conforms to the pseudo-second-order kinetic model and Langmuir model. Scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential characterization results showed that the adsorption process is mainly physical adsorption, surface complexation and ion exchange. Full article
(This article belongs to the Special Issue Energy Systems and Applications in Agriculture)
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