Tag Archives: renewable energy

365-376 V. Chiteculo, A. Brunerová, P. Surový and M. Brožek
Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes
Abstract |

Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes

V. Chiteculo¹*, A. Brunerová²*, P. Surový¹ and M. Brožek²

¹Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Department of Forest management, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz; chiteculo@fld.czu.cz

Abstract:

In the Federative Republic of Brazil, Jatoba (Hymenaea courbaril) and Garapa (Apuleia leiocarpa) trees are intensively harvested. The yield of one log is approximately 45–55%, which indicates a great amount of produced wood waste biomass.Present research monitored the suitability of wood waste biomass from Jatoba and Garapa trees for bio–briquette for solid biofuel production. The research was focused on chemical parameters,and energy potential of such biomass kinds. Jatoba wood waste biomass was used for the production of bio–briquette fuel and its final mechanical quality was investigated by determination of their mechanical quality indicators. Results of chemical analysis (in wet basis) exhibited great level of ash content in case of both species (Jatoba – 0.31%, Garapa – 3.02%), as well as high level of energy potential; net calorific value equal to 18.92 MJ kg–1 for Jatoba and to 18.395 MJ kg–1 for Garapa. Analysis of elementary composition proved following levels of oxygen content: Jatoba – 41.10%, Garapa – 39.97%. Mechanical analysis proved bio–briquette samples volume density ρ equal to 896.34 kg m–3 which indicated quality bio–briquette fuel, while the level of rupture force RF occurred at a lower level – 47.05 N mm–1. Most important quality indicator, the mechanical durability DU, unfortunately, occurred at a lower level; DU = 77.6% compared to the minimal level of bio–briquette fuels intended for commercial sales which must be > 90%. Overall analysis proved materials suitability for energy generation purpose with certain limitations which can improve by changing production parameters of briquetting.

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656-668 A. Brunerová, H. Roubík, M. Brožek and J. Velebil
Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops
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Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops

A. Brunerová¹*, H. Roubík², M. Brožek¹ and J. Velebil³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Department of Sustainable Technologies, Kamýcká 129, CZ165 00 Prague, Czech Republic
³Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz

Abstract:

Energy consumption in Indonesia and Vietnam has grown rapidly in recent decades. To meet the energy needs of both countries, a higher utilisation of waste biomass sources may represent an adequate solution. Investigated samples represent major crop residues (waste biomass) originating mainly from the agriculture sector of the selected countries. Herbaceous waste biomass from Indonesia is, namely, cassava stems and root peelings (Manihot esculenta), coffee leaves (Coffea arabica), cacao leaves (Theobroma cacao), banana leaves (Musa acuminata), bamboo leaves (Bambusoideae spp.) and aloe vera leaves (Aloe vera). Furthermore, fruit and aquatic waste biomass originating from Vietnam is, specifically, sugarcane bagasse (Saccharum officinarum), durian peelings (Durio zibethinus), rambutan peelings (Nephelium lappaceum), banana peelings (Musa acuminata), water milfoil (Myriophyllum spicatum) and water hyacinth (Eichhornia crassipes). All mentioned types of waste biomass were subjected to proximate and calorimetric analysis: moisture, ash and volatile matter contents (%) and higher and lower heating values (MJ kg–1). Obtained values indicated the highest level of ash content in fruit biomass samples in the case of sugarcane bagasse (0.84%), in herbaceous biomass in the case of cassava stems (3.14%) and in aquatic biomass in the case of water hyacinth (14.16%). The highest levels of lower heating values were achieved by following samples (best samples from each biomass type): cassava stems (17.5 MJ kg–1); banana peelings (17.3 MJ kg–1) and water hyacinth (12.8 MJ kg–1). The overall evaluation of all observed samples indicated that the best suitability for energy utilisation by direct combustion of investigated representatives is fruit waste biomass, followed by herbaceous waste biomass and then aquatic waste biomass.

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1247-1256 K. Sirviö, S. Niemi, R. Help, S. Heikkilä and E. Hiltunen
Kinematic viscosity studies for medium-speed CI engine fuel blends
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Kinematic viscosity studies for medium-speed CI engine fuel blends

K. Sirviö*, S. Niemi, R. Help, S. Heikkilä and E. Hiltunen

University of Vaasa, Faculty of Technology, PL 700, FIN-65101 Vaasa, Finland
*Correspondence: katriina.sirvio@uva.fi

Abstract:

Engine-driven power plants, run by diesel fuel or gas, will be needed for peaking power to keep the electricity grids stable when the production of renewable electricity, e.g. utilizing wind or solar power, is increased.
The choice of the alternative, renewable fuels for engine-driven power plants and marine applications is at the moment quite narrow. The amount of renewables of all liquid fuels is at present less than 2%. Biodiesels, FAMEs, have been studied for long time and apparently, despite of the problems they may have, they are still in the great interest. One important increment to the category of alternatives is fuels that are produced from e.g. oil wastes, i.e., recycled fuels. They are not renewable, but recycling of potential energy raw materials is still one step forward in increasing the suitable and more sustainable options.
To utilize the blends in medium-speed engines for power production, accurate knowledge of the physical and chemical properties of fuel blends is very important for the optimization of engine performance. The determination of the fuel kinematic viscosity is needed to create proper fuel atomisation. The injection viscosity affects directly the combustion efficiency and the engine power. Consequently, this study focused on measuring kinematic viscosity curves for seven fuel blends, as well as the neat fuels used for blending. The temperature range was 10–90 °C. The fuels used for blending were rapeseed methyl ester, animal-fat based methyl ester, hydro-treated vegetable oil, light fuel oil and marine gas oil produced from recycled lubricating oils.

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xxx V. Chiteculo, A. Brunerová, P. Surový and M. Brožek
Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes
Abstract |

Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes

V. Chiteculo¹*, A. Brunerová²*, P. Surový¹ and M. Brožek²

¹Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Department of Forest management, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz; chiteculo@fld.czu.cz

Abstract:

In the Federative Republic of Brazil, Jatoba (Hymenaea courbaril) and Garapa (Apuleia leiocarpa) trees are intensively harvested. The yield of one log is approximately 45–55%, which indicates a great amount of produced wood waste biomass.Present research monitored the suitability of wood waste biomass from Jatoba and Garapa trees for bio–briquette for solid biofuel production. The research was focused on chemical parameters,and energy potential of such biomass kinds. Jatoba wood waste biomass was used for the production of bio–briquette fuel and its final mechanical quality was investigated by determination of their mechanical quality indicators. Results of chemical analysis (in wet basis) exhibited great level of ash content in case of both species (Jatoba – 0.31%, Garapa – 3.02%), as well as high level of energy potential; net calorific value equal to 18.92 MJ kg–1 for Jatoba and to 18.395 MJ kg–1 for Garapa. Analysis of elementary composition proved following levels of oxygen content: Jatoba – 41.10%, Garapa – 39.97%. Mechanical analysis proved bio–briquette samples volume density ρ equal to 896.34 kg m–3 which indicated quality bio–briquette fuel, while the level of rupture force RF occurred at a lower level – 47.05 N mm–1. Most important quality indicator, the mechanical durability DU, unfortunately, occurred at a lower level; DU = 77.6% compared to the minimal level of bio–briquette fuels intended for commercial sales which must be > 90%. Overall analysis proved materials suitability for energy generation purpose with certain limitations which can improve by changing production parameters of briquetting.

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344–358 A. Brunerová, M. Brožek and M. Müller
Utilization of waste biomass from post–harvest lines in the form of briquettes for energy production
Abstract |
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Utilization of waste biomass from post–harvest lines in the form of briquettes for energy production

A. Brunerová*, M. Brožek and M. Müller

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and anufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic *Correspondence:brunerova@tf.czu.cz

Abstract:

A great amount of herbal waste biomass is produced nowadays during agriculture crop processing; also during ‘post–harvest lines’ operations. Such waste biomass occurs in the bulk form, thus, is not suitable for direct combustion; it can be improved by using of briquetting technology. Therefore, present paper provides chemical, mechanical and microscopic analyses of waste biomass originating from post–harvest lines and briquettes produced from it. Namely, waste biomass originated from production of oat (Avena sativa) – husks, wheat (Triticum spp.) – husks and poppy (Papaver somniferum) – straw and seed pods and mixture of all mentioned were investigated. Unprocessed materials were subjected to microscopic and chemical analysis and subsequently produced briquette samples were subjected to determination of its mechanical quality. A satisfactory level of moisture and ash content was observed, as well as, materials energy potential; oat – 17.39 MJ kg-1, wheat – 17.04 MJ kg-1, poppy – 14.48 MJ kg-1. Also microscopic analysis proved suitability of all feedstock materials within evaluation of geometrical shapes of their particles. However, evaluation of briquette mechanical quality unsatisfactory results. Process of briquetting revealed unsuitability of oat feedstock for briquette production; other materials proved following values of volume density and mechanical durability (in sequence): wheat – 1,023.19 kg m-3, 89.1%; poppy – 1,141.43 kg m-3, 94.7%; mixture – 972.49 kg m-3, 62.7%. In general, only poppy briquettes achieved requested mechanical quality level for commercial briquette production. However, undeniable advantage of investigated materials is the form they occurred in; no further feedstock preparation (drying, crushing) was needed.

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456–467 M. Križan, K. Krištof, M. Angelovič and J. Jobbágy
The use of maize stalks for energy purposes and emissions measurement during their combustion
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The use of maize stalks for energy purposes and emissions measurement during their combustion

M. Križan, K. Krištof*, M. Angelovič and J. Jobbágy

University of Agriculture in Nitra, Faculty of Engineering, Department of Machines and Production Biosystems, Tr. A. Hlinku 2, SK949 76 Nitra, Slovakia
*Correspondence: koloman.kristof@uniag.sk

Abstract:

Biomass is an ideal renewable energy with advantages of abundance resources and neutral in greenhouse gas circulation. Majority of this energy could have been used directly in agriculture itself. The rest of the biomass for other parts of industry or even communal parts could be made available as a refined and densified biomass available for direct combustion in form of bales. The objective of the work was a monitoring of possibilities of maize cortical use for energy purposes during combustion. Emissions measurement from the combustion of maize phytomass was performed by measuring device TESTO 350 M/XL. During the combustion of packages with the moisture of 18% and 38% was monitored and the effect of moisture on the content of gas emissions of CO, CO2, NO, NO2 as well as the percentage of residual O2 in the flue gas after combustion. All values of monitored emission limits were in current normative limits defined in Collection of Laws no. 356/2010. All emissions limits are in accordance to monitored standards for CO, CO2, NO, NO2, but on the other hand it should be noted that the more favourable results are based on combustion of cortical with moisture of 18% than at 38%. The issue of maize cortical harvesting considering machinery, technological and economical viewpoint within the Slovak republic but also worldwide is poorly understood and therefore these issues should be the subject of further research.

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1101–1106 A. Mäkiranta, B. Martinkauppi and E. Hiltunen
Seabed sediment – a natural seasonal heat storage feasibility study
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Seabed sediment – a natural seasonal heat storage feasibility study

A. Mäkiranta*, B. Martinkauppi and E. Hiltunen

University of Vaasa, Faculty of Technology, Electrical Engineering and Energy Technology, P.O. Box 700, FI-65101 Vaasa, Finland
*Correspondence: anne.makiranta@uva.fi

Abstract:

The new discovery among renewable energy resources, seabed sediment, has been utilised as a heat source for 42 houses in Vaasa since 2008. Sediment heat is annually loaded by the Sun. In this study the amount of annually charged energy is estimated. The difference of sediment temperatures between the coldest and the warmest month during the year is a key value in the approximation of the loaded energy. Sediment temperatures are measured once per month via optical cable by distributed temperature sensing (DTS) method. The monitoring period is three years, 2014–2016. The estimation of incoming energy (575 MWh) versus known exploited energy (560 MWh) is reasonable. Despite of the extraction this seasonal heat storage in the seabed of the Baltic Sea seems to reload well annually.

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359–368 A. Brunerová, J. Malaťák, M. Müller, P. Valášek and H. Roubík
Tropical waste biomass potential for solid biofuels production
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Tropical waste biomass potential for solid biofuels production

A. Brunerová¹*, J. Malaťák², M. Müller¹, P. Valášek¹ and H. Roubík³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague, Czech Republic
³Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Department of Sustainable Technologies, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz

Abstract:

Subsequent utilization of waste biomass in developing countries occurs at poor level, despite the  act, that it has great potential in solid biofuel production. Densified waste biomass is utilized for  direct combustion, therefore, its suitability (energy potential, chemical composition) must be determined in attempt to protect environment and reduce air pollution. Main aim of present research was to determine suitability of waste biomass originating from production of rice (Oryza sativa), Date fruit (Phoenix dactylifera L.) and Jatropha fruit (Jatropha curcas) for solid biofuel production. Within a moisture, ash and volatile matter contents, major chemical elements (C, H, N, O) and net calorific value (NCV) were determined. Rice waste analysis proved low NCV (14.33 MJ kg–1) and high ash content (20.74%), which presented problems during combustion. Jatropha fruit waste (cake) analyses exhibited outstanding NCV (24.44 MJ kg–1) caused by residual oil content. Within major elements analysis a low content of oxygen (26.61%) was proved (recommended). Date fruit waste exhibited average NCV (16.40 MJ kg–1). However, high oxygen content (44.01%) was defined as limiting factor. Overall evaluation proved greatest suitability for Jatropha fruit waste (cake), followed by Date fruit waste and lowest potential was determined for Rice waste. However, investigated plants are not cultivated for energy production purposes, thus, observed results achieved satisfactory level of their suitability for solid biofuel production.

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322–328 M. Bloch-Michalik and M. Gaworski
Agricultural vs forest biomass: production efficiency and future trends in Polish conditions
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Agricultural vs forest biomass: production efficiency and future trends in Polish conditions

M. Bloch-Michalik* and M. Gaworski

Department of Production Management and Engineering, Warsaw University of Life Sciences, PL02-787 Warsaw, Nowoursynowska str. 164, Poland
*Correspondence: marta_michalik@sggw.pl

Abstract:

Biomass is one of the main sources of renewable energy with rapidly growing trend in the European Union countries. The technical potential of biomass energy in Poland is one of the highest in Europe, estimated at approximately 900 PJ/year. Solid biomass is the primary Polish RES and the share in the structure of production in Poland amounted to almost 77% in 2015. The most common types of biomass are waste raw materials from crop fields and forests.
The paper presents current potential of the biomass of two basic types, i.e. agricultural and forest material, based on the analyses developed with the scenario forecast of future use in Poland. Detailed considerations include differences in efficiency of agricultural and forest biomass production. To develop the efficiency aspects some indices were proposed to compare potential of energy production basing on different kind of biological material.

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1720-1729 T. Vaimann, A. Rassõlkin, A. Kallaste and M. Märss
Feasibility study of a local power supply system for sparsely populated areas in Estonia
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Feasibility study of a local power supply system for sparsely populated areas in Estonia

T. Vaimann¹²*, A. Rassõlkin¹, A. Kallaste¹² and M. Märss¹³

¹Tallinn University of Technology, Faculty of Power Engineering, Department of Electrical Engineering, Ehitajate tee 5, EE19086 Tallinn, Estonia
²Aalto University, School of Electrical Engineering, Department of Electrical Engineering and Automation, PO Box 13000, FI00076 Aalto, Finland
³Estonian University of Life Sciences, Institute of Technology, Department of Energy Engineering, Fr.R. Kreutzwaldi 56/1, EE51014 Tartu, Estonia
*Correspondence: toomas.vaimann@ttu.ee

Abstract:

The paper analyzes the reasonability of using an off-grid hybrid power supply system or in other words a local grid for sparsely populated areas as well as the necessary components selection and price development of such system. Typical consumers are selected and all estimations and calculations are based on them. Consumer profiles are set and analyzed as well as different elements of the local power supply grid and the possibility of connecting to the traditional grid. Estonian example is used in this paper as the country lies relatively north and has some remote areas, where local power supply grids can be implemented. All prices in the paper are derived from the Estonian example. Necessity of further study is proposed.

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