Evaluation of specific energy consumption and GHG emissions for different drying methods (Case study: Pistacia Atlantica)

Abstract Okra pods were dried using the following drying regimes; microwave (MWD), infrared (IRD) and convective hot-air drying (CHD). The objective of this investigate was to report the influences of drying methods on okra quality under different drying conditions. Data analysis showed that rehydration ratio and colour change increased with increase in drying air temperature and air velocity while specific energy consumption and shrinkage ratio decreased with increase in drying air temperature under (CHD). The rehydration ratio and colour of dried okra increased with increase in both infrared intensity but it also increased with a decrease in air velocity under (IRD). In the MWD method, drying time, specific energy consumption and shrinkage ratio decreased with increases in microwave power while the rehydration ratio and colour increased. Optimum drying period, specific energy consumption, colour, shrinkage and rehydration ratio were obtained for microwave drying. The model of Midilli et al. is the greatest for describing the drying curves of okra under all the drying processing conditions.

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Wastewater treatment process impact on energy savings and greenhouse gas emissions

Water Science & Technology ◽

10.2166/wst.2014.521 ◽

2014 ◽

Vol 71 (2) ◽

pp. 303-308 ◽

Cited By ~ 48

Author(s):

D. Mamais ◽

C. Noutsopoulos ◽

A. Dimopoulou ◽

A. Stasinakis ◽

T. D. Lekkas

Keyword(s):

Wastewater Treatment ◽

Energy Consumption ◽

Greenhouse Gas ◽

Energy Savings ◽

Wastewater Treatment Plants ◽

Specific Energy Consumption ◽

Ghg Emissions ◽

Wastewater Treatment Process ◽

Conventional Activated Sludge

The objective of this research was to assess the energy consumption of wastewater treatment plants (WWTPs), to apply a mathematical model to evaluate their carbon footprint, and to propose energy saving strategies that can be implemented to reduce both energy consumption and greenhouse gas (GHG) emissions in Greece. The survey was focused on 10 WWTPs in Greece with a treatment capacity ranging from 10,000 to 4,000,000 population equivalents (PE). Based on the results, annual specific energy consumption ranged from 15 to 86 kWh/PE. The highest energy consumer in all the WWTPs was aeration, accounting for 40–75% of total energy requirements. The annual GHG emissions varied significantly according to the treatment schemes employed and ranged between 61 and 161 kgCO2e/PE. The highest values of CO2 emissions were obtained in extended aeration systems and the lowest in conventional activated sludge systems. Key strategies that the wastewater industry could adopt to mitigate GHG emissions are identified and discussed. A case study is presented to demonstrate potential strategies for energy savings and GHG emission reduction. Given the results, it is postulated that the reduction of dissolved oxygen (DO) set points and sludge retention time can provide significant energy savings and decrease GHG emissions.

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Determination of drying kinetics, specific energy consumption, shrinkage, and colour properties of pomegranate arils submitted to microwave and convective drying

Open Agriculture ◽

10.1515/opag-2020-0209 ◽

2021 ◽

Vol 6 (1) ◽

pp. 230-242

Author(s):

Mohammad Kaveh ◽

Iman Golpour ◽

João Carlos Gonçalves ◽

Sara Ghafouri ◽

Raquel Guiné

Keyword(s):

Energy Consumption ◽

Air Temperature ◽

Specific Energy ◽

Specific Energy Consumption ◽

Drying Kinetics ◽

Drying Methods ◽

Colour Properties ◽

Drying Time ◽

Effective Moisture ◽

Pomegranate Arils

Abstract In this study, the drying kinetics, effective moisture diffusivity (D eff), specific energy consumption (SEC), colour, and shrinkage (S b) of pomegranate arils were compared when dried by convective (CV) drying and microwave (MW) drying. The experiments were performed at air temperature of 50, 60, and 70°C and air velocity of 1 m/s for CV drying and 270, 450, and 630 W for MW drying. The results showed that increasing air temperature and MW power increased the D eff. The calculations demonstrated that the maximum D eff for pomegranate arils was obtained for MW drying (630 W). Maximum SEC for pomegranate arils in the CV dryer was 145.12 kWh/kg, whereas in the MW dryer was 35.42 kWh/kg. In MW dryer, the lowest values of colour change and shrinkage were 6.77 and 50.5%, respectively. Comprehensive comparison of the different drying methods (MW and CV) revealed that MW drying had best drying performance for pomegranate arils, considering the drying time, effective moisture diffusion, SEC, colour, and shrinkage.

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Reducing specific energy consumption by conserving energy and increasing energy efficiency in low tension distribution and utilisation — A case study

IECON 2015 - 41st Annual Conference of the IEEE Industrial Electronics Society ◽

10.1109/iecon.2015.7392183 ◽

2015 ◽

Author(s):

K. Suresh ◽

J. Devishree

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Specific Energy ◽

Specific Energy Consumption ◽

Tension Distribution ◽

Low Tension

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Energy Efficiency of Inland Waterways Transport for Agriculture: The Ukraine Case Study

Applied Sciences ◽

10.3390/app11198937 ◽

2021 ◽

Vol 11 (19) ◽

pp. 8937

Author(s):

Oleg Bazaluk ◽

Valerii Havrysh ◽

Vitalii Nitsenko

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Specific Energy ◽

Specific Energy Consumption ◽

Inland Waterways ◽

Inland Navigation ◽

The Status ◽

National Production ◽

Transport Management

In Ukraine, there has been an increase in agricultural production. The availability of river basins and seaports contributes to the use of inland shipping. However, there is a lack of understanding of how to reduce the energy consumption of inland shipping. We assume the hypothesis that the energy efficiency of inland shipping is much higher than it is technically possible. The purpose of this study is to identify perspective energy-saving technologies for IWT. We use statistical information to determine the export potential and to reveal the status of inland navigation. Traction efficiency, theoretical and actual specific fuel consumption were used as indicators to determine the energy efficiency. The main results are as follows. We have found the grain and sunflower seed production in the Dnieper Basin (Ukraine). Their shares range from 34.75 to 50.92% of national production. Therefore, there is a significant flow of products for inland shipping. The present status of inland waterways transport has been analyzed. The main novelty of this study is the finding of actual and theoretical technical specific energy consumption. It is revealed that actual specific energy consumption is five times higher compared to the theoretical one. Self-propelled vessels are inferior in energy efficiency to towing barges. The energy efficiency of inland waterways transport has been compared to railways and road freight transport. Transport management was identified as the more effective tool to improve the energy efficiency of inland shipping.

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Microwave Processing of Foam Materials

MRS Proceedings ◽

10.1557/proc-269-447 ◽

1992 ◽

Vol 269 ◽

Author(s):

W. Van Loock

Keyword(s):

Energy Consumption ◽

Specific Energy ◽

High Frequency ◽

Specific Energy Consumption ◽

Conveyor Belt ◽

Cellular Materials ◽

Foam Material ◽

Drying Time ◽

Time Constants

ABSTRACTThe distinct phases in the production process of a foam material are foaming, curing and drying. Cellular materials are insulators to conventional heat. This paper discusses the effectiveness of microwave or high frequency energy for processing a layer of foam material on for example a conveyor belt. The emphasis is on the thermal and drying time constants and on the specific energy consumption. It is demonstrated that a limit is set on time gain when using microwaves.A case study for applying microwaves in an industrial production line of foam rubber for mattresses according to the above principles is presented.

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