Volume 10 (2012)
  Special Issue I

International Scientific Conference
Biosystems Engineering 2012

10.-11. May 2012, Tartu, Estonia

Conference information – PDF (62 K)

Contents


Pages

3-10 A. Aan and M. Heinloo
Computer based comparison analysis of single and double–connecting–rod slider–crank linkages
Abstract |
Full text PDF (190 kB)

Computer based comparison analysis of single and double–connecting–rod slider–crank linkages

A. Aan and M. Heinloo

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia; e-mail: aare.aan@emu.ee

Abstract:

This paper presents the results of comparative numerical analysis of single and double–connecting–rod slider–crank linkages on the worksheet of Computer Package Mathcad. On the base of composed virtual models of both linkages the motion of the slider (piston) in these linkages is studied thoroughly. This paper has the links to the video clips, comparing the motions of single and double–connecting–rod slider–crank linkages and visualizing the change of vectors of velocities and accelerations in the pivot, where connects two links of double connecting rod. Concluded, that the motion of the slider (piston) and the force of reaction to the track of slider (wall of a cylinder) in these linkages is quite different.

Key words:

, ,




11-16 A. Abánades
The challenge of Hydrogen production for the transition to a CO2-free economy
Abstract |
Full text PDF (168 kB)

The challenge of Hydrogen production for the transition to a CO2-free economy

A. Abánades¹ ²

¹Institute for Advanced Sustainability Studies, Berliner Straße 130. D-14467 Potsdam,
Germany
²Universidad Politécnica de Madrid, c/Ramiro de Maeztu 7, E-28040, Spain;
e-mail: abanades@etsii.upm.es

Abstract:

The energy demand of the world is foreseen to be increased due to the improvements
on the living standard of the developing countries and the development of the global economy.
The increase in sustainability of the energy supply must be considered as a must to avoid
spoiling natural resources for the next human generations and more dramatic effects such as the
so-called global atmospheric warming. The utilization of CO2-free energy sources, as in the
case of renewables, is one of the most promising ways to attain such objectives. Nevertheless,
the massive energy production with such energy sources are far from being practically feasible
in the short-medium term and an innovative solution should be put into practice for the CO2-
free exploitation of the huge fossil fuel resources already available. This general assumption is
also applicable to any energy carrier such as Hydrogen or electricity. In this case, an analysis is
done of the Hydrogen production processes and the discussion of the need to develop a CO2-
free production scheme like methane cracking is shown. 

Key words:

, ,




17-24 A. Beloborodko, L. Timma, A. Žandeckis and F. Romagnoli
The regression model for the evaluation of the quality parameters for pellets
Abstract |
Full text PDF (149 kB)

The regression model for the evaluation of the quality parameters for pellets

A. Beloborodko, L. Timma, A. Žandeckis and F. Romagnoli

Institute of Environment and Energy Systems, Riga Technical University,
Kronvaldablvd. 1, Riga, LV-1010, Latvia; e-mail: anna.beloborodko@rtu.lv

Abstract:

In Latvia no European legislation concerning the quality of the production of pellets is adopted. Since the market is not regulated by any governmental regulations, biofuel testing is not compulsory. This aspect leads to a situation where pellets of various qualities are available on the market. The main objective of this paper is to compare the characteristics of the pellets which are produced in various regions of Latvia. The second goal is to develop a regression model which describes the influence of the independent aspects (physical parameters, price, trading form, transportation distance etc.) on the pellet quality. The quality parameters for the solid biofuels were determined according to the methods described in the Technical Specifications of the European Commission for Standardization. The regression model for the pellet quality has been implemented using the software STATGRAPHICS Centurion 16.1.15. The results of the research emphasize that the physical parameters of the pellets vary widely. Three regression models were built in order to describe the influence of the various parameters on the indicator (price per net calorific value) and on the mechanical quality of the pellets. The fitted Models were described by the regression equation given in the paper.

Key words:

, ,




25-38 D. Blumberga, L. Lipsane, I. Laicane, J. Gusca and S. N. Kalnins
Analysis of wood fuel chain in Latvia
Abstract |
Full text PDF (245 kB)

Analysis of wood fuel chain in Latvia

D. Blumberga, L. Lipsane, I. Laicane, J. Gusca and S. N. Kalnins

Institute of Energy Systems and Environment, Riga Technical University, Kronvalda
bulvaris 1, LV-1010, Riga, Latvia; e-mail: dagnija.blumberga@rtu.lv

Abstract:

The objective is to investigate solid biofuels logistic system’s stages and to develop regional firewood supply network, which would include storage terminals by choice, exploring several possible scenarios and developing conclusions about supply optimization results. Analysis of supply and demand markets of wood fuel in Latvia, focusing on region that includes Jelgava, Tukums, Dobele and Bauska districts were investigated in the research. In the defined researched region geographical location of boiler houses and storage terminals from perspectives of increasing of solid biofuel demand was observed. A method that allows calculating optimal production flow and expected costs for final customers (boiler houses) within different scenarios and delivery options was developed. In addition the model demonstrates differences between direct production flow of wood fuel and flow through storage terminals. Linear programming and mixed integer programming models implementation is carried out using Xpress Solver in combination with geographical data processing with ArcGis 9.3.

Key words:

, , , ,




39-48 J. Frorip, E. Kokin, J. Praks, V. Poikalainen, A. Ruus, I. Veermäe, L.Lepasalu, W. Schäfer, H. Mikkola, J. Ahokas
Energy consumption in animal production – case farm study
Abstract |
Full text PDF (154 kB)

Energy consumption in animal production – case farm study

J. Frorip¹, E. Kokin¹, J. Praks¹, V. Poikalainen¹, A. Ruus¹, I. Veermäe¹, L.Lepasalu¹, W. Schäfer², H. Mikkola³, J. Ahokas³

¹Estonian University of Life Sciences, Kreutzwaldi 1, EE51014, Tartu, Estonia;
e-mail: juri@monte.ee
²MTT Agrifood Research Finland, Agricultural Engineering Research
(MTT/VAKOLA), Vakolantie 55, FI-03400 Vihti, Uusimaa, Finland;
e-mail: winfried.schafer@mtt.fi
³Department of Agrotechnology, University of Helsinki, P.O. Box 28 (Koetilantie 3),
FI-00014 Helsinki, Finland;
e-mail: Jukka.ahokas@helsinki.fi; hannu.j.mikkola@helsinki.fi

Abstract:

The objective of this study was to analyse the energy use by the dairy case-farm with un-insulated cowsheds in Estonia for the period of 2009-2010. The energy balance calculation includes the direct energy input of fuel, lubricants and electricity and the indirect input of forage, cereals, concentrates for young stock, dairy cattle and buildings. Energy outputs are milk, meat, and manure. The energy values were calculated multiplying the quantities of inputs and outputs by their energy conversion factors. The quantitative parameters of the inputs and outputs are based on book-keeping data, the energy conversion factors of feed were measured. The energy output-input ratio of the case-farm was 1.88 in 2009 and 1.85 in 2010. Energy input of milk was 5.4 and 5.3 per MJ kg-1, respectively. Our study indicated that the case farm energy consumption is generally higher than that of comparable European dairy farms. The further research is needed to find the reason of mentioned differences.

Key words:

, , ,




49-54 S. Saeid Hosseini and Mohsen Shamsi
Performance optimization of a rotary mower using Taguchi method
Abstract |
Full text PDF (169 kB)

Performance optimization of a rotary mower using Taguchi method

S. Saeid Hosseini and Mohsen Shamsi

Department of mechanics of Agricultural Machinery, Shahid Bahonar University of
Kerman, Kerman, Iran; e-mail: saeid_hossaini@yahoo.com

Abstract:

Optimum energy consumption and prevention of energy losses are important issues in various fields including agricultural engineering. Mower is one of the agricultural machineries that can waste too much energy if does not function properly. In this study, the performance of a single disc rotary mower was studied and optimized by measurement of cutting quality of the stem cross section (cutting quality) as a criterion. Taguchi L9 orthogonal arrays table was used to find the optimum combination of parameters to reach the best cutting quality. The selected factors are: mower forward velocity, disc rotational speed, number of disc blades and shape of the blade, each one at 3 different levels. To measure the quality of the cut hay, ENVI image processing software was used. This software has been developed for texture qualification of image processing studies. The texture of the images captured from the cross section of cut stems by the mower is analyzed according to the reflected wavelength from the surface. ENVI software assigns a number to the cutting quality of each stem, which is called eigenvalue. The results then were imported to the orthogonal arrays table of the Taguchi method. Minitab software was used to calculate the optimal level of the studied variables. Analysis of the results show that 886 rpm of the disc rotational speed, 1m s-1 of the forward speed, four symmetrical triangular serrated blades on the mower disc are the optimal values of the factors and offer the highest cutting quality. The optimum value predicted by the Taguchi method was approved by an experimental method.

Key words:

, , , ,




55-74 R. Ilves and J. Olt
Study of prior art of spark ignition engine fuel supply system
Abstract |
Full text PDF (336 kB)

Study of prior art of spark ignition engine fuel supply system

R. Ilves and J. Olt

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia; e-mail: risto.ilves@emu.ee

Abstract:

The technical development of contemporary fuel supply systems is vast. Reasons for development include improving the economical parameters of engines as well as decreasing the concentration of exhaust fumes. The aim of this particular article is to define, firstly, the technical standard of the fuel supply systems of spark ignition combustion engines, and secondly, the validity of the given patent. For these purposes, a literature-based overview of the engines’ fuel supply systems, their developments and most pertinent parts will be provided. The structural specialties of fuel supply systems are analyzed and their suitability for using bio fuels will be reviewed. Innovative solutions for upgrading the fuel supply systems so that liquid bio fuels could be used in spark ignition engines will be given.

Key words:

, , , , , , ,




75-84 A. Jasinskas, I. Ulozevičiūtė, E. Šarauskis and A. Sakalauskas
Impact of immature willows stems chopping quality on the harmful emissions evaluation
Abstract |
Full text PDF (163 kB)

Impact of immature willows stems chopping quality on the harmful emissions evaluation

A. Jasinskas, I. Ulozevičiūtė, E. Šarauskis and A. Sakalauskas

Aleksandras Stulginskis University, Faculty of Agricultural Engineering, KaunasAkademija,
Studentu str. 15A, LT-53361 Kauno r., Lithuania;

Abstract:

The analytical review of the experimental research results of energy plants preparation, burning efficiency and the emissions of harmful substances into the air while burning these plants, is presented in this paper. After the experimental study, immature (1–2 year of growth) willow (Salix viminalis) stems chaff chopping quality were observed. In truth, use of the drum chopping equipment prepared chaff fractional composition, and there were defined and calculated immature willow stems chaff of theoretical length (from 11.8 till 61.3 mm). They were presented and compared with the experimental research results of the low power boiler efficiency and harmful emissions into the air while burning energy plants – immature willow, chopped by the drum chopper of Maral-125 combine. The test was carried out in the laboratory of the low power boiler, which is designed to burn wood, wood briquettes and large wood chaff. After determination of boiler efficiency and harmful substances (CO2, CO, NO, NOx) emissions into the environment while burning different lengths of willow chaff, it was concluded that the boiler developed about 66–86% of nominal boiler power, and pollution emissions concentration into the environment was lower when willow chaff of 49.2 mm length was burned.

Key words:

, , , , , , ,




85-95 T. Jokiniemi, H. Mikkola, H. Rossner, L. Talgre, E. Lauringson, M. Hovi and J. Ahokas
Energy savings in plant production
Abstract |
Full text PDF (287 kB)

Energy savings in plant production

T. Jokiniemi¹, H. Mikkola¹, H. Rossner², L. Talgre², E. Lauringson², M. Hovi³ and J. Ahokas¹

¹Department of Agrotechnology, University of Helsinki, P.O. Box 28, 00014 Helsinki,
Finland; e-mail: tapani.jokiniemi@helsinki.fi; hannu.j.mikkola@helsinki.fi;
jukka.ahokas@helsinki.fi
²Institute of Agricultural and Environmental Sciences, Estonian University of Life
Science, Kreutzwaldi 1, EE51014 Tartu, Estonia; e-mail: helis.rossner@emu.ee;
liina.talgre@emu.ee; enn.lauringson@emu.ee
³Institute of Technology, Estonian University of Life Science, Kreutzwaldi 56,
EE51014 Tartu, Estonia; e-mail: mart.hovi@emu.ee

Abstract:

At the moment energy costs in agriculture are relatively low compared to other costs. In 2010 energy costs were 10% of the total agricultural costs in Finland. However, energy costs are expected to grow. The EU has made a directive on Energy End-Use Efficiency and Energy Services, which claims that agriculture must save 9% of their average energy consumption of the period 2001–2005. The highest energy consumptions in plant production originate from agro-chemicals (fertilizers, lime and pesticides). However, regarding energy statistics, energy consumption for agrochemicals is allocated to the industrial sector. Chemicals are for this reason seen as indirect energy in agriculture. Direct energy input in agriculture consists of fuels and electricity. The most dominating direct energy input in plant production is diesel and heating oil. Energy consumption can be easily decreased in plant production by some 10–30%. For instance, 10–20% of energy can be saved in grain drying by heat insulation. In machine operations the dominating factor in energy consumption is the driver. With properly implemented maintenance and adjustment and efficient driving habits, 10–30% savings can be achieved

Key words:

, ,




97-107 T. Jokiniemi, H. Rossner and J.Ahokas
Simple and cost effective method for fuel consumption measurements of agricultural machinery
Abstract |
Full text PDF (135 kB)

Simple and cost effective method for fuel consumption measurements of agricultural machinery

T. Jokiniemi¹, H. Rossner² and J.Ahokas¹

¹Department of Agrotechnology, University of Helsinki, P.O. Box 28, 00014 Helsinki,
Finland; e-mail: tapani.jokiniemi@helsinki.fi; jukka.ahokas@helsinki.fi
²Institute of Agricultural and Environmental, Estonian University of Life Sciences,
Kreutzwaldi 1, Tartu EE51014, Estonia; e-mail: helis.rossner@emu.ee

Abstract:

Energy saving objectives in agriculture have created a demand for energy consumption figures of single field operations and for total fuel consumption in farm level. Although the fuel consumption of field operations is quite well known in general level, the conditions in different locations and years result in variation between these figures. In order to create an energy analysis for a single farm, a way to measure the fuel consumption on site is needed. The most useful unit for fuel consumption in most of the farming field operations is l ha-1, since it enables the comparison between different farms and years. Using this unit also reduces the effect of uncontrollable factors, for example weather and soil conditions. In this study, a simple and cost effective way to measure the fuel consumption of agriculture machinery in l ha-1 was tested. The fuel consumption was measured by the voltage signal of machine’s own fuel level sensor. The signal was recorded with a voltage data logger, and movements of the machine were recorded with a simple personal GPS-tracker. Manual bookkeeping was also made to provide support for data analysis. A calibration curve was created for each machine to calculate the corresponding fuel level for each voltage reading. Measuring system was inexpensive, easy to install and did not require any modifications to the fuel system. It can also be installed to almost any tractor or other self propelled farm machine. Results showed that this is a useful measuring method with certain restrictions. The measuring period has to be relatively long to obtain reliable results, and therefore the continuous working periods for each working phase has to be long enough. The conclusion was that this kind of measuring system can be used to provide average values for energy analysis and also to detect the critical points in the production system.

Key words:

, , , , , ,




109-113 M. H. Jorgensen
Agricultural Field Machinery for the future – from an Engineering Perspective
Abstract |

Agricultural Field Machinery for the future – from an Engineering Perspective

M. H. Jorgensen

Department of Mechanical and Manufacturing Engineering, Aalborg University,
Fibigerstraede 16, DK-9220 Aalborg East, Denmark; e-mail: mhj@m-tech.aau.dk

Abstract:

When analyzing agricultural field machinery from an engineering perspective, it appears that the technical development has progressed in a different pattern compared to what is seen in other industrial mechanical or tooling systems. As in other fields, the technical development of agricultural field machinery has brought new technical and engineering elements into use. Especially for tractors and combine harvesters, where modern mechanical and control engineering solutions are implemented. Developing work on implements has more concerned on monitors, sensors and actuators for the classical adjustment elements. It is special for agricultural field machinery, that the overall design and the tooling principles have changed very little even since the time of horse driven units and during the following up-scaling of tractor and implement size, which has continuously taken place until now, where the power of an tractor is more than 10 times bigger, than for the first tractors. When analyzing the design of industrial mechanical or tooling systems, the technological and engineering based development has in many cases been accompanied by change of working principles, operation interactions and of the overall design and layout. The assumption is that the development of agricultural field machinery is in a stage where further up-scaling is not the best solution due to optimization of the overall production economy. Instead it is expected probable, that the next design step will involve a radical redesign of the whole systems for the different types of implements. A logical approach is development of compact integrated tooling systems, where propulsion and tooling systems will be integrated in harmonic systems and the design will be dedicated to specific operations. The sizing then, will be balanced due to a new set of conditions.

Key words:

, , , , , , , ,




115-122 S. Kalinauskaite, A. Sakalauskas, E. Šarauskis, A. Jasinskas, M. Ahlhaus and H. Gerath
Biomass preparation for conversion humidity and value assessment
Abstract |
Full text PDF (265 kB)

Biomass preparation for conversion humidity and value assessment

S. Kalinauskaite, A. Sakalauskas, E. Šarauskis, A. Jasinskas¹, M. Ahlhaus² and H. Gerath³

¹Aleksandras Stulginskis University, Studentų g. 11, Akademija, Kauno r. LT-53361,
Lithuania; e-mail: solveiga.kalinauskaite@gmail.com
²Fachhochschule Stralsund, Institut für Regenerative EnergieSysteme (IRES), Zur
Schwedenschanze 15, 18435 Stralsund, Germany;
e-mail: Matthias.Ahlhaus@fh-stralsund.de
³Hochschule Wismar, Philipp-Müller-Straße PF 1210 Wismar 23952, Germany;
e-mail: horst.gerath@hs-wismar.de

Abstract:

Biomass usage for heat and energy purposes is one of the questions which still required more detailed analysis and scientific research. In this research we have focused on an analysis of humidity correlation on biomass preparation to conversion steps and calorific value assessment. The concept of biomass is widely understood, and in this research the chosen research object is agricultural, biomass with a main focus on straw, and additionally for results comparison are analyzed samples, composition are a mixture of straw and hay, with an additional 2% lime additive. For this research analyzed samples and their humidity for production steps is: one chop size reduction (20 mm) straw briquettes, two chops size reduction (30 mm and 10 mm) straw briquettes, pallets composition of 100% straw, 98% straw incl. 2% lime additive, 50% straw and 50% hay, 49% straw and 49% hay incl. 2% lime additive, 100% hay, 98% hay incl. 2% lime additive. Samples of straw and hay mixture, also with a lime additive is choosen because it is discussed widely that not only is it possible to use surplus straw from agricultural biomass as renewable energy and heat source, as a lime additive helps to keep a higher temperature on the combustion process and to generate more energy, but it is not healthy for the plant and not recommended under environmental aspects. The results received will help to estimate and determine the material humidity impact on biomass preparation for conversion steps, following an energy requirement for the production of briquettes and pallets, combustion factor and efficiency. It is defined as material calorific, HHV (higher heating value) and ash content which is one of the main factors and the criteria for fuel valuation will allow to determine tested samples further usage for heat and energy purposes. The research results will help further research tasks on bio energy as an agricultural biomass usage.

Key words:

, , , ,




123-129 T. Kaps, R. Reiska, U. Kallavus, M. Koolme, Ü. Luga and J. Kers
Effective protection of pinewood against fungal attack
Abstract |
Full text PDF (237 kB)

Effective protection of pinewood against fungal attack

T. Kaps¹, R. Reiska¹, U. Kallavus², M. Koolme¹, Ü. Luga¹ and J. Kers¹

¹Chair of Woodworking Department of Polymer Materials, Tallinn University of
Technology, Teaduspargi 5, EE12618, Tallinn, Estonia; e-mail: jaan.kers@ttu.ee
²Centre for Materials Research, Faculty of Chemical and Materials Technology,
Ehitajate tee 5, Tallinn EE19086, Estonia

Abstract:

This paper gives an overview about an effective protection technology of pinewood. The new impregnation emulsion based on rapeseed-oil and boron compounds was developed and tested. To compare the efficiency of new impregnate widely used ‘Tanalith E’ wood preservative was used. The obtained results demonstrate that the new impregnation agent ensures effective protection against wood rotting fungi and discolouring fungi. Bio testing according to the EN113 at Latvian State Institute of Wood Chemistry revealed that the new preservative ensures effective protection against wood rotting fungi (mass loss less than 3%) and discolouring fungi (mould).

Key words:

, ,




131-138 P. Kliimak, M. Luik, A. Leola and M. Reinvee
Analysis of students’ assessments about the noise educational lecture
Abstract |
Full text PDF (142 kB)

Analysis of students’ assessments about the noise educational lecture

P. Kliimak, M. Luik, A. Leola and M. Reinvee

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia; e-mail: kliimak@emu.ee; matis.luik@emu.ee;
arvo.leola@emu.ee; mart.reinvee@emu.ee

Abstract:

Exposure to excessive noise is a major cause of preventable hearing disorders worldwide. Most cases of noise-induced hearing loss are caused by occupational noise exposure. The importance of using hearing protection in the workplace is nowadays well recognized and most industries have programs and regulations in place to ensure the hearing health of their workers. Far less attention has been paid to hearing disorders due to noise during leisure time, although the sound levels of such occasions can exceed occupational safety limits. Moreover, noise induced hearing loss has become one of the biggest health issues among young people’s life at the present time. Researchers have noticed that it is mainly caused by being exposed to loud noises during leisure time activities: visiting concerts, nightclubs, sporting events or listening to music with loud devices, such as MP3 players. Average sound level can be between 95…115 dB(A) on such occasions. The aim of this study was to compose a noise educational lecture for young adults to improve their knowledge about noise and increase their awareness of preventable hearing loss. The noise educational lecture was conducted among students and a feedback questionnaire was handed out to gather students’ assessments about the lecture in order to carry out an evaluation process to determine the lecture’s effectiveness. In this article, data about the methodology of the feedback questionnaire and results are presented in order to give an overview of students’ opinion about the noise educational lecture and make an evaluation of the lecture.

Key words:

, , ,




139-148 A. Küüt, O. Panova and J. Olt
Characteristics describing the price formation of bioethanol used as the fuel for an internal combustion engine
Abstract |
Full text PDF (207 kB)

Characteristics describing the price formation of bioethanol used as the fuel for an internal combustion engine

A. Küüt, O. Panova and J. Olt

Institute of Technology, Estonian University of Life Sciences, 56 Kreutzwaldi,
EE51014 Tartu, Estonia; e-mail: arne.kyyt@emu.ee

Abstract:

A wider introduction of bioethanol as a biorenewable fuel is hindered by low awareness. The main problems related with its use are related to the properties of bioethanol fuel as well as the differences arising from its energetic value in comparison with regular fuels. This raises questions concerning the economic purposefulness of using bioethanol. In order to describe bioethanol as a motor fuel, a comparative analysis was performed based on experimental research. Experimental research allows for establishing a calculation model that describes the use of bioethanol as a fuel for an internal combustion engine in case of different ethanol content and various mixture ratios with regular fuels. The parameters to be studied and compared include the quantity and price of the fuel based on ethanol content. The comparative characteristics derived from the calculation model are indicated in tables and in figures. Calculation model creates a connection between using bioethanol as a motor fuel, and its production, thus providing useful information when choosing the production technology.

Key words:

, , ,




149-155 A. Menind, L. Oper, M. Hovi, J. Kers, M. Tutt and T. Kikas
Pretreatment and usage of pulp and paper industry residues for fuels production and their energetic potential
Abstract |
Full text PDF (174 kB)

Pretreatment and usage of pulp and paper industry residues for fuels production and their energetic potential

A. Menind¹, L. Oper², M. Hovi¹, J. Kers³, M. Tutt¹ and T. Kikas¹

¹Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia; e-mail: andres.menind@emu.ee
²Institute of Economics and Social Sciences, Estonian University of Life Sciences,
Kreutzwaldi 1, EE51014 Tartu, Estonia; e-mail: liis.oper@emu.ee
³Department of Polymer Materials, Tallinn University of Technology;
e-mail: jaan.kers@ttu.ee

Abstract:

This paper gives an overview about Pulp and Paper Industry (PPI) residues, their properties and some solutions for converting those materials into fuels. The main leftovers are bark, sludge of aerobic digestion, primary floto sediment (PFS) and pulp rejects (PR). PFS and PR after applying dewatering (press fluids) have considerable biogas potential. Bark and press cake of PR are a good resource for briquetting. Ethanol potentials of bark and PR cake are presented.

Key words:

, , , , , , , ,




157-166 V. Mikita, J. Roots and J. Olt
Simulation model of the combustion processes of a diesel engine
Abstract |
Full text PDF (157 kB)

Simulation model of the combustion processes of a diesel engine

V. Mikita¹, J. Roots² and J. Olt¹

¹Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014, Tartu, Estonia; e-mail: villu.mikita@emu.ee,
²Institute of Economics and Social Sciences, Estonian University of Life Sciences,
Kreutzwaldi 56, EE51014 Tartu, Estonia

Abstract:

It is foreseen that in the near future in Estonia there will be growth in the consumption of alternative liquid fuels in internal combustion engines. The main share of it will be formed by the local raw material based diesel fuel and ethanol. In connection with this, the choice of fuels and the variety of their qualitative characteristics in filling stations will grow. This kind of situation will give rise to the necessity of creating new quality assessment methods which should be reliable, efficient and economical. There may be several assessment methods for taking fuel samples. Drivers consider the fuel quality assessment express methods especially valuable. Working out a new method like that is at present also supported by the electronic control system of the engine and the use of digital diagnostic devices. Creating and implementing the fuel quality assessment express method requires a considerable amount of effort. It includes the evaluation and prognosis of the fuels physical and chemical parameters, designing the simulation models of the engine combustion process pressure and temperature and carrying out the control testing.

Key words:

, ,




167-174 A. Normak, J. Suurpere, K. Orupõld, E. Jõgi and E. Kokin
Simulation of anaerobic digestion of cattle maure
Abstract |
Full text PDF (193 kB)

Simulation of anaerobic digestion of cattle maure

A. Normak¹, J. Suurpere¹, K. Orupõld¹, E. Jõgi² and E. Kokin²

¹Institute of Agricultural and Environmental Sciences, Estonian University of Life
Sciences, Kreutzwaldi 5, EE51014 Tartu, Estonia; e–mail: argo.normak@emu.ee
²Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia

Abstract:

IWA Anaerobic Digestion Model No.1 (ADM1) was used to simulate the anaerobic digestion process of cattle slurry. The model was applied to 200 l single stage completely stirred tank reactor. The simulation results of pH, biogas flow rate, acetate and methane concentration were under study. Ammonia inhibition constant was optimized during this study to improve modelling results compared to measurements of acetate concentration. Maximum methane yield during experiment was 291 l (kg VSadded) -1 at organic loading rate 2.0 kg VS (m3 d)-1.

Key words:

, ,




175-180 E. Nugis and J. Kuht
Outline of results concerning assessment of soil compaction in Estonia
Abstract |
Full text PDF (125 kB)

Outline of results concerning assessment of soil compaction in Estonia

E. Nugis¹ ² and J. Kuht³

¹Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, Tartu,
Estonia, EE51014; e-mail: edvin.nugis@emu.ee
²Estonian Research Institute of Agriculture, Teaduse 13, Saku, Estonia,
EE75501;e-mail: edvin.nugis@eria.ee 3
³Institute of Agricultural and Environmental Sciences, Estonian University of Life
Sciences, Kreutzwaldi 56, Tartu, Estonia, EE51014; e-mail: jaan.kuht@emu.ee

Abstract:

In Estonia the effect of compaction on soil/subsoil is studied in two leading organizations: Estonian University of Life Sciences (EMÜ) and Estonian Research Institute of Agriculture (ERIA). An attempt has been made to methodologically harmonize them with methodological instructions given in the ISTRO (International Soil Tillage Research Organization). A novel methodology for complex assessment of the effect and influence of mobile technical means (MTM) on soil has been offered. The soil has been examined as a polydisperse body where certain changes occur in compactibility, vulnerability, achieving physical mellowness and in textural composition. The relevant assessment criteria were worked out and approved in three separately carried out tests. As it appears from the results, such an approach allows us to do the necessary generalizations in assessment of the effect of MTM on soil, to adequately value the respective factors (extent, character, sign systems), i.e. issue from soil physical properties and pedosemiotics characteristics at the same time, while also not excluding the energy consumption.

Key words:

, , , , ,




181-186 J. Olt and V.V. Maksarov
Using an anisotropic properties of sheetmetal to develop a design of vibrationless cutting tool
Abstract |
Full text PDF (664 kB)

Using an anisotropic properties of sheetmetal to develop a design of vibrationless cutting tool

J. Olt¹ and V.V. Maksarov

¹Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56, Tartu,
EE51014, Estonia;
²National Mineral Resources University ‘Mining University’, Vasilevsky island,
21 line, the house 2, St.-Petersburg, 199106, Russia

Abstract:

The article proposing a new technology for manufacturing of vibration-proof tool with multilayered damping tool holder. Desired damping effect is obtained by anisotropic properties of tool holder plates, as a result from machining by pressure a source material. The experimental research in the piece processing allows to provide effective dynamic absorbing of vibration. This method is more effective (in comparison with standard methods) because it have high coefficients of damping and absorption. The value of dissipative force of multilayered tool holder material (with differently directed structure) is enough to ensure a good damping effect.

Key words:

, , , ,




187-194 V. Poikalainen, J. Praks, I. Veermäe and E. Kokin
Infrared temperature patterns of cow’s body as an indicator for health control at precision cattle farming
Abstract |
Full text PDF (304 kB)

Infrared temperature patterns of cow’s body as an indicator for health control at precision cattle farming

V. Poikalainen, J. Praks, I. Veermäe and E. Kokin

Estonian University of Life Sciences, Kreutzwaldi 1, EE51014, Tartu, Estonia

Abstract:

Cows’ infrared radiation temperature study was carried out at experimental cowshed (120 cows) of Estonian University of Life Sciences. Thermal image scanner Fluke TiS was used for obtaining 640×480 pixels thermal images with resolution of 0.1°C. The temperature distribution pattern of different parts of cow’s body was estimated and analysed with SmartView software. Special attention was paid to udder, feet and areas with skin injuries. It was estimated that the temperature varies considerably at different parts of the body. Radiation temperature of healthy udder did not change considerably after milking. It means that automatic monitoring of udder temperature is possible not only in milking parlour or milking robot but also in other places where cows are identified. The udder thermograms enable to assess the milking hygiene, as the cleanliness of udder surface influences the measurement results, especially average temperature. The temperature of legs was lowest at the hoofs and highest at coronary band. Differences from this distribution may be used for estimation of leg disorders. Thermal images can be also successfully used for detection of skin injuries. Radiation temperature of injured and depilous locations was higher by several degrees than their surroundings. The study showed that thermal images analysis is promising method to be implemented at precision cattle farming.

Key words:

, , ,




195-204 M. Rajaniemi and J. Ahokas
A case study of energy consumption measurement system in broiler production
Abstract |
Full text PDF (311 kB)

A case study of energy consumption measurement system in broiler production

M. Rajaniemi and J. Ahokas

Department of Agrotechnology, University of Helsinki, P.O. Box 28, 00014 Helsinki,
Finland

Abstract:

Energy savings in animal production have become increasingly important due to climate change and rising energy prices. In order to find potential savings, the energy consumption and its allocation inside the production systems must be known. The biggest energy input in broiler production is feed. To reduce this energy input the savings must be done in crop and feed production chain. This study focused on the direct energy consumption inside the broiler house. Ventilation, lighting, feeding and heating systems consume also a considerable large amount of energy. However, information of this energy consumption is incomplete, and variation between different locations, farms and broiler batches is large. In this study, the energy consumption of broiler production was measured in one insulated broiler house in Southern Finland. Energy consumption was measured from ventilation, lighting, feeding and heating during broiler batches. Also environmental factors, such as indoorand outdoor temperatures, carbon dioxide level and relative humidity were measured continuously, because they have an effect on energy consumption and the microclimate inside the building must be kept good. This data can also be used in calculations of ventilation heating demand. Energy consumption of ventilation, feeding and lighting were measured with current clamps. Clamps were located in the electrical center, and energy consumption was calculated from the measured current and voltage. Data was saved on a data logger. Heating energy was measured from the heating pipes. Energy consumption was calculated from the temperature difference of incoming and outgoing water and water flow rate. Measured data was uploaded from the data loggers after every broiler batch. Energy consumption was calculated for each broiler batch and per kg of slaughter weight.

Key words:

, ,




205-209 M. D. Rasmussen
Educational requirements to support research and innovation in Bioenergy
Abstract |
Full text PDF (111 kB)

Educational requirements to support research and innovation in Bioenergy

M. D. Rasmussen

Department of Engineering, Aarhus University. Blichers Allé 20, DK-8830 Tjele,
Denmark;
e-mail: mdr@ase.au.dk

Abstract:

Conversion of biomasses to energy, food, feed and chemical building blocks for
further usage become increasingly important. Educations and research within biorefinery and
especially bioenergy have become popular and are offered at most universities in Europe.
Bioenergy is a very wide scientific area however, and we must educate students that possess the
qualifications to bring the industry and research forward. We must not just educate students that
know some general elements but students that really can go into the depth. Universities should
specialise and seek partners to complement educations and research areas.

Key words:

, ,




211-218 O. Sada, E. Mikson and B. Reppo
Ammonia emission in cowsheds and pigsties during the summer periood
Abstract |
Full text PDF (164 kB)

Ammonia emission in cowsheds and pigsties during the summer periood

O. Sada, E. Mikson and B. Reppo

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014 Tartu, Estonia

Abstract:

As is known, cows in uninsulated cowsheds can tolerate lower temperatures much better than higher temperatures, so we can say that these buildings are well suited for animals, although there are problems with workers and the working environment in uninsulated cowsheds in extreme cases, during very low and high outside temperatures. The goal of this study was to identify the outdoor climate impact on the indoor climate in cowsheds with 420, 500 and 500 cow places during winter and summertime. For that, indoor and outdoor temperature, relative humidity and indoor ammonia content were measured simultaneously. The processed results are well applicable when designing new cattle housing or improving the indoor climate of already existing uninsulated cowsheds. Building of large pigsties with deep litter and without litter which use liquid manure removal systems has become a wide practice nowadays. Indoor climate parameters of the working environment have an impact on the human capacity for work and the productivity of animals. Enlargement of pigsties is accompanied with problems regarding the achievement of the required indoor climate for the working environment. For the purpose of studying the pigsties with different animal-keeping technologies and the simultaneous effect of temperature and relative humidity on the emission ammonia content in the air of a pigsty were measured in summer above a pig-pen at the height of 1.5 meters from the floor and were measured daily. Data logger equipment, relevant sensors and content of ammonia in the air was measured for the study by using Gas Monitor Pac III equipment. Measurement results were statistically processed by using the computer programmes AMR Win Control, Pac III Software3.nn, SAS and MS Excel.

Key words:

, , , , , , , , , , , , ,




219-226 A. Salinš, M. Freimanis, R. Truhanovs and J. Priekulis
The most effi cient solutions of forage distribution on modern dairy cow farms
Abstract |
Full text PDF (157 kB)

The most effi cient solutions of forage distribution on modern dairy cow farms

A. Salinš, M. Freimanis, R. Truhanovs and J. Priekulis

Institute of Agricultural Engineering, Latvia University of Agriculture, J.Čakstes bulv.
5, LV-3001, Latvia

Abstract:

The most efficient technological solutions of forage mix preparation and distribution on modern farms with herds of 100 to 600 cows have been investigated. Seven different technologies were compared – technologies applying mobile equipment and those applying forage distribution robots. Technological versions were evaluated by specific labour intensity and specific operational costs. For this reason a mathematical model was worked out, using computer simulation programme MatLab Simmulink. Calculations were based on the timekeeping data of the technological lines of forage preparation and distribution obtained on the farms included in the research. It was ascertained that it is more efficient to apply technologies that propose all operations to be performed by a single mobile technological unit. If the number of cows in the herd does not exceed 370, it is efficient to use a tractor unit with a frontally hooked scoop for loading silage and with a forage mixer-distributor hooked on the backside, but in the case of more cows, it is more efficient to use a unit of self-propelled type. Forage distribution robots can compete with mobile distributors if concentrated feed is included in the feed mix and if separately arranged stations are not used for this purpose.

Key words:

, , , ,




227-234 V. Zagorska, I. Ziemelis, L. Kancevica and H. Putans
Experimental investigation of photovoltaic-thermal hybrid solar collector
Abstract |
Full text PDF (297 kB)

Experimental investigation of photovoltaic-thermal hybrid solar collector

V. Zagorska, I. Ziemelis, L. Kancevica and H. Putans

Latvia University of Agriculture, Liela Street 2, Jelgava, LV-3001, Latvia;

Abstract:

From August 6 2011 till September 29 2011 an experimental investigation of hybrid classic photovoltaic-thermal solar collector MWPVT-1414 was carried out. The hybrid solar battery had produced 23.01 kWh of electric energy during 55 days of investigation, or 0.418 kWh per day on average. It was calculated that during the summer months from March 1 till November 1 the amount of electric energy produced by the battery could be about 100 kWh. The highest cooling water temperature was 43°C, which is 16°C higher than the surrounding air temperature.

Key words:

, , ,




235-242 M. Zajicek and P. Kic
Improvement of the broiler house ventilation using the CFD simulation
Abstract |
Full text PDF (439 kB)

Improvement of the broiler house ventilation using the CFD simulation

M. Zajicek¹ and P. Kic²

¹Institute of Information Theory and Automation, The Academy of Science of The
Czech Republic, v.v.i., Pod vodarenskou vezi 4, 182 00, Prague 5, Czech Republic

²Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, 165
21, Prague 6, Czech Republic

Abstract:

The need for an exact control of the indoor conditions in buildings is the main reason for different simulation methods as a help for designers and researchers. This paper is focused on the numerical analysis of ventilation of building for broilers during the summer period with the use of computer fluid dynamics (CFD) software from Fluent Inc. The summer period is particularly critical. This paper presents the results of measurement and CFD analysis of the flow pattern, thermal state and concentration of pollutants inside the broiler house. Calculation respected the Czech standard. Final results show the improved arrangement of ventilation. There are a lot of aspects which has to be included in the process of improving the function of an existing broiler house ventilation system. It is commonly required to find an acceptable balance between the financial costs and maximum obtainable functionality of the system. It is usually impossible to make great structural and interior changes for houses and therefore the geometrical shape and the configuration of inlets and outlets is almost definitely a given and non-changeable condition. The paper presents the CFD solution of miscellaneously improved cases for the various flow and shape configurations of the broiler house. Effects of the transversal and longitudinal ventilation are combined with the changes of inlet air streams directions and also with the different cross-section shaping obtained using curtains. All cases are evaluated and compared according to the same methodology. Results are discussed in terms of an existing state and also in terms of the expected costs needed for the ventilation system reconstruction.

Key words:

, ,




243-250 K. Tamm and R. Vettik
The model to define optimum volume for slurry tanker
Abstract |
Full text PDF (130 kB)

The model to define optimum volume for slurry tanker

K. Tamm and R. Vettik

Research Institute of Agriculture, 13 Teaduse St. EE75501 Saku, Estonia;

Abstract:

The capacity of a slurry tanker is affected by different variables. According to previous studies, the most significant influence is the tank volume. In the present version of the selection model of a tanker a pattern is composed to determine the optimum volume for a slurry tanker. The aim of the paper is to introduce the pattern and give an overview of the model. The optimality criterion is minimum slurry distribution cost. In the results the importance of optimum value for tank volume is discussed and the impact of a non-optimal solution is explained. The the impact of the parameters on distribution costs is also clarified. The calculations show that the bigger the annual amount, the longer the transportation distance is and the shorter the tolerated distribution period – then the bigger the optimum value is for the tank size if slurry is transported with the distributor itself. Only for short distances (<3 km) and big slurry amounts (>4,000 m3 ) is the transportation with the distributor itself a cost benefit. However, in most of the cases it is cheapest to use a separate tanker for slurry transportation, while the distance has no effect on the optimum size of a distributor tank. There, in most cases only one set of the application equipment is required to supply the farm with sufficient distribution capacity. If an annual amount is 4,000 m3 or less then a 5 m3 tank is sufficient to serve a farm with the required distribution capacity. If an annual amount is 8,000 m3 then a 10 m3 tank is optimal.

Key words:

, , ,




251-260 P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle
Vibration and noise caused by lawn maintenance machines in association with risk to healt
Abstract |
Full text PDF (141 kB)

Vibration and noise caused by lawn maintenance machines in association with risk to healt

P. Tint, G. Tarmas, T. Koppel, K. Reinhold and S. Kalle

Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia;

Abstract:

The aim of this study was to compare vibration and noise characteristics caused by different types of lawn maintenance machines in association with the risk factors to workers’ health. In the present study, the method connecting vibration hazard, health damages and risk levels is presented. Three types of agriculture machines were investigated: all-terrain vehicles (ATV), simple lawn-mowers, ride-on mowers. These machines are used not only in occupational settings, but also by the inhabitants for cutting grass. The gardeners and maintenance workers of the municipal authorities use them daily, sometimes 8 hours a day. The protective equipment against noise is used in occupational settings, but hardly by the public. Noise was evaluated using a Sound Level Meter (TES 1358) following the standard ISO 9612:2009. Vibration was determined as acceleration, velocity and amplitude – measured using a Vibration Dosimeter & Analyser (SV 100) following the standards ISO 2631-4, EVS-EN 5349-2. The risk to the health is assessed by the original flexible risk assessment method worked out in TTU. On the basis of this flexible model the scheme for connecting the local and whole-body vibration hazards and possible health damages was worked out. The results showed that there are differences in the noise and vibration generated by the ATV, lawn-mowers and ride-on mowers. The safest was ride-on mower (local vibration below 1.15 m (s2 ) -1). Lawnmowers gave high vibration levels (over 3 m (s2 ) -1). The personal protective equipment (PPE) has to be worn by all users of the investigated machines. The noise spectral content by these three types of machines is presented and it is different. This enables to choose the right type of ear-muffs by the frequency of noise. The PPE against vibration is also available.

Key words:

, ,




261-268 P. Tint, A. Traumann, V. Pille, V.-R. Tuulik-Leisi and V. Tuulik
Computer users’ health risks caused by the simultaneous infl uence of inadequate indoor climate and monotonous work
Abstract |
Full text PDF (206 kB)

Computer users’ health risks caused by the simultaneous infl uence of inadequate indoor climate and monotonous work

P. Tint, A. Traumann, V. Pille, V.-R. Tuulik-Leisi and V. Tuulik

Tallinn University of Technology, Ehitajate 5, EE19086 Tallinn, Estonia.

Abstract:

This paper is aimed at improving the workplace ergonomics of computer workers (working as information-technologists or in offices and at the till of trade companies). The paper includes the assessment of the risk of monotonous work, but also the influence of indoor climate conditions on development of health damages at workplace (developing carpal channel syndrome). A questioning of workers was carried out (Kiva questionnaire) to clarify the opinion of workers about the work atmosphere at the workplace. The novelty of the study is that the work conditions (indoor climate, lighting, noise) are closely connected with the monotonousness of the work. Cold temperatures (<20°C in office), bad lighting (<300 lx at the till or <400 lx in the office) are supplementary factors for developing the musculoskeletal disorders. The results of analysis of repetitive work (ART tool) show that the intensity of work for workers totally engaged in info-technology is high, but in some way monotonous, therefore health problems like musculoskeletal disorders are very common. The rehabilitation possibilities are proposed. The questioning of the workers showed that the workers working with computers are focused on their own work tasks and do not require very much the relations with the co-workers.

Key words:

, ,




269-276 M. Tutt, T. Kikas and J. Olt
Influence of different pretreatment methods on bioethanol production from wheat straw
Abstract |
Full text PDF (179 kB)

Influence of different pretreatment methods on bioethanol production from wheat straw

M. Tutt, T. Kikas and J. Olt

Institute of Technology, Estonian University of Life Sciences, Kreutzwaldi 56,
EE51014, Tartu, Estonia; e-mail: marti.tutt@emu.ee

Abstract:

Article investigates the influence of different pretreatment methods on sugar
conversion and bioethanol production. Different dilute acid and alkaline pretreatment methods
are compared to determine the best pretreatment method to give the highest glucose and ethanol
yields under the mild operating conditions. Wheat straw is used as a raw material as it is the
most widely grown cereal in Europe. Dilute sulfuric acid, hydrochloric acid, nitric acid and
potassium hydroxide solutions are used for pretreatment in combination with enzymatic
hydrolysis. Results indicate that the highest cellulose-to-glucose conversion rate of 316.7 g kg-1
of biomass is achieved by the pretreatment with nitric acid. The lowest glucose concentration of
221.3 g kg-1 is achieved by hydrochloric acid. In the wheat straw samples pretreated with
sulfuric acid and KOH, two different approaches are used. Solid phase of half the samples is
rinsed with water before adding enzymes, and the rest of the samples are not. The rinsed
samples pretreated with KOH solution give the highest ethanol yield of 104.3 g kg-1, while the
lowest ethanol yield is 67.7 g kg-1 from samples pretreated with HCl solution. Unrinsed samples
and rinsed samples pretreated with sulfuric acid give an ethanol yield of 78.7 g kg-1 and
92.0 g kg-1, respectively. These results indicate that rinsing the solid phase of the samples with
distilled water before hydrolysis removes most of the inhibitory compounds formed during the
pretreatment with dilute acid and increases fermentation efficiency by approximately 12%. 

Key words:

, , , ,