Tag Archives: emissions.

1254-1265 L. Paura, L. Berzina, L. Degola, E. Aplocina, D. Kairisa, D. Jonkus and O. Skiste
Trends in milk yield productivity and emissions from the dairy sector in Latvia
Abstract |
Full text PDF (782 KB)

Trends in milk yield productivity and emissions from the dairy sector in Latvia

L. Paura¹, L. Berzina¹*, L. Degola², E. Aplocina², D. Kairisa², D. Jonkus² and O. Skiste³

¹Latvia University of Life Sciences and Technologies, Faculty of Information Technologies, Department of Control Systems, Liela street 2, LV–3001 Jelgava, Latvia
²Latvia University of Life Sciences and Technologies, Faculty of Agriculture, Institute of Animal Sciences, Liela street 2, LV–3001 Jelgava, Latvia
³Latvia University of Life Sciences and Technologies, Faculty of Environment and Civil Engineering, Department of Environment and Water Management, Akademijas street 19, LV–3001 Jelgava, Latvia
*Correspondence: laima.berzina@llu.lv

Abstract:

Dairy cow productivity continuously increased in Latvia in recent years. Despite decreasing numbers of dairy cow population dairy farms have been identified as an important source of greenhouse gas (GHG) emissions. Dairy sector emissions create the largest share of enteric fermentation emissions as well as emissions from manure in housing facilities, during long-term storage and field application within agriculture sector total emissions. The main objective of this study is to present the results of trend analysis in the productivity of the dairy sector and corresponding emission in Latvia. Research is focused on analysis of dairy cow productivity and feeding strategies to quantify the effect of increasing milk yield on GHG emissions. In the framework of this research, emissions were calculated and evaluated for low and high productivity dairy cows according to the methodology of ‘2019 Refinement to the 2006 Guidelines for National Greenhouse Gas Inventories’. During the last decade dairy cow productivity in Latvia has increased and the average milk yield in standard lactation was 8,320 kg per year in 2021. It was observed that 60% of the total number of dairy cows met the requirements of a high-productivity system, while 40% of the dairy cows belonged to low-productivity systems in Latvia. Research results show that total GHG emissions for high-productivity system can reach 5.3 kt CO2 eq. per 1,000 cows per year, however, for low-productivity system the total amount of emissions does not exceed 3.1 kt CO2 eq. per 1,000 cows.

Key words:

, , , ,



1575-1585 A. Lenerts, K. Naglis-Liepa, D. Popluga, Dz. Kreišmane, E. Aplociņa, L. Bērziņa and O. Frolova
Marginal abatement cost curve for an ammonia reduction measure in agriculture: the case of Latvia
Abstract |
Full text PDF (498 KB)

Marginal abatement cost curve for an ammonia reduction measure in agriculture: the case of Latvia

A. Lenerts¹*, K. Naglis-Liepa¹, D. Popluga¹, Dz. Kreišmane², E. Aplociņa², L. Bērziņa³ and O. Frolova³

¹Latvia University of Life Sciences and Technologies, Faculty of Economics and Social Development, Institute of Economics and Regional Development, 18 Svetes street, LV-3001 Jelgava, Latvia
²Latvia University of Life Sciences and Technologies, Faculty of Agriculture, 2 Liela street, LV-3001 Jelgava, Latvia
³Latvia University of Life Sciences and Technologies, Faculty of Environment and Civil Engineering, 19 Akademijas street, LV-3001 Jelgava, Latvia
*Correspondence: arnis.lenerts@llu.lv

Abstract:

With the production of grain and livestock–derived agricultural commodities increasing, the agricultural sector has become one of the main sources of ammonia (NH3) emissions in Latvia. In 2018, the agricultural sector contributed to 83% of the total NH3 emissions originated in Latvia (15.46 kt) (LIIR 2020). The EU has already put in place measures to control NH3 emissions. This includes the EU target of reducing ammonia emissions by 21% by 2030 and sets out emission reduction commitments for Latvia. Considering Latvia’s indicative reduction target, the NH3 emission reductions need to be achieved by 2030 (Directive 2016/2284) so that the emissions do not exceed the 2005 level (11.33 kt). Implementing no mitigation measures, Latvia has projected agricultural sector NH3 emissions to be 32.4% higher than those in 2005, and therefore the mitigation of the NH3 emissions from agriculture is important. The research aims to estimate cost-effective NH3 emission reduction measures in agriculture in Latvia. The results of the research represent a marginal abatement cost curve (MACC) analysis, in which we have quantified the potential for reduction for selected NH3 emission mitigation measures in Latvia. A list of the measures has been established taking into account the experience of good agricultural practices in the reduction of NH3 emissions (UN, 2014) and of other European countries as well. The calculations carried out allowed us to group the measures according to their priorities: measures that are cost-effective and with high potential for reduction of NH3; measures that are cost-effective but with low NH3 emission reduction potential; measures that are not cost-effective but with high potential for reduction of NH3; measures that are not cost-effective and with low potential for reduction of NH3. The estimated cumulative (total) reduction of NH3 emissions in Latvian agriculture by 2030, with the implementation of the measures analysed, is equal to 20.08 kt.

Key words:

, , , ,



2033-2048 M. Hissa, S. Niemi and A. Niemi
Combustion and emission studies of a common-rail direct injection diesel engine with various injector nozzles
Abstract |
Full text PDF (1 MB)

Combustion and emission studies of a common-rail direct injection diesel engine with various injector nozzles

M. Hissa*, S. Niemi and A. Niemi

University of Vaasa, School of Technology and Innovations, P.O. Box 700, FI-65101 Vaasa Finland
*Correspondence: Michaela.Hissa@univaasa.fi

Abstract:

Fuel injection has a critical role in an internal combustion engine and a significant effect on the quality of the fuel spray. In turn, fuel spray directly affects an engine´s combustion, efficiency, power and emissions. This study evaluated three different injector nozzles in a high-speed, non-road diesel engine. It was run on diesel fuel oil (DFO) and testing was conducted at three different engine loads (100%, 75% and 50%) and at two engine speeds (2,200 rpm and 1,500 rpm). The nozzles had 6, 8 and 10 holes and a relatively high mass flow rate (HF). The study investigated and compared injection and combustion characteristics, together with gaseous emissions. The combustion parameters seemed to be very similar with all studied injector nozzles. The emission measurements indicated general reductions in hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx) at most load/speed points when using the 6- and 10-hole nozzles instead of the reference 8-hole nozzles. However, smoke number increased when the alternative nozzles were used.

Key words:

, , , ,



1001–1012 M. Holúbek, M. Pexa, J. Čedík and D. Mader
Effect of long-term operation of combustion engine running on n-butanol – rapeseed oil – diesel fuel blend
Abstract |
Full text PDF (1 MB)

Effect of long-term operation of combustion engine running on n-butanol – rapeseed oil – diesel fuel blend

M. Holúbek*, M. Pexa, J. Čedík and D. Mader

Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamýcká 129, CZ165 21, Prague 6, Czech Republic
*Correspondence: holubekm@tf.czu.cz

Abstract:

The short time use of biofuels in compression ignition engines is being studied by many authors. However, in many cases the real long–term operation of the engine on biofuels may cause problems. The article deals with the operation parameters of the combustion engine, fuelled by n-butanol – rapeseed oil – diesel fuel blend, during 70 hours operation in total. Two brand new diesel power generators Kipor KDE 6500 with output power of 4.6 kW were used for certain testing. The first generator was operated on 100% diesel fuel and it was used as a reference and the second generator was operated on experimental fuel containing 10% n-butanol – 20% rapeseed oil – 70% diesel fuel blend. The generators were equipped with single cylinder compression ignition engine Kipor KM 186 with the rated power of 5.7 kW. For the first 10 operating hours approx. 40% load was applied. Then, the generators worked for another 60 operating hours with approx. 70% load. The harmful emissions, smoke, fuel consumption and the amount of produced particles were also measured after 10 hours run-in period and then after another 60 hours of operation. Consequently, the results were compared. Measurements were carried out at gradually increasing electric power output, approx. 14%, 28%, 42%, 56%, 68%, 82% and 95% (in results can be found in Watts). Emission analyser and opacimeter BrainBee and Engine Exhaust Particle Sizer TSI were used for the measurements. The results showed increased production of emission of the engine running on fuel blend after 70 hours of operation. On the other hand, engine which operated on standard diesel reached lower fuel consumption. After 70 hours the blended fuel tended to produce more particles in comparison with diesel fuel.

Key words:

, , , , ,



157-166 J. Malaťák, J. Bradna, J. Velebil, A. Gendek and T. Ivanova
Evaluation of dried compost for energy use via co-combustion with wood
Abstract |
Full text PDF (599 KB)

Evaluation of dried compost for energy use via co-combustion with wood

J. Malaťák¹*, J. Bradna¹, J. Velebil¹, A. Gendek² and T. Ivanova³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 21 Prague, Czech Republic
²Warsaw University of Life Sciences, Department of Agricultural and Forest Machinery, Faculty of Production Engineering, Nowoursynowska 166, PL02-787 Warsaw, Poland
³Czech University of Life Sciences, Faculty of Tropical AgriSciences, Department of Sustainable Technologies, Kamýcká 129, CZ165 21 Prague, Czech Republic
*Correspondence: malatak@tf.czu.cz

Abstract:

There is still a question of utilization of compost of unsatisfactory quality. This article deals with energy utilization of untreated compost. The energy utilization of raw compost as a fuel is not directly possible without further processing. Separation might be necessary due to large amount of mineral content (soils and other inert substances).
This article is focused on the analysis of the basic fuel characteristics of compost. Proximate and elemental analyses were performed and stoichiometric combustion was calculated. Finally, the sample was co-burned with wood biomass in a fixed grate combustion device and the gaseous emissions were determined in dependence on the amount of combustion air supplied. The emissions were expressed in graphs against excess air coefficient and flue gas temperature.
Elemental analysis of the compost sample shows high percentage of ash up to 61.70% wt. on dry basis causing low average calorific value of 8.51 MJ kg-1 on dry basis. For combustion tests, the heating value was increased by addition of wood chips to reach an average calorific value of the mixture to 13.4 MJ kg-1. The determined stoichiometric parameters can help in optimization of diffusion controlled combustion of composts or similar materials. In combustion of the mixture of compost and wood biomass an optimum of emission parameters was found not exceeding the emission limits. Measured emission concentrations show the possibility of optimizing the combustion processes and temperatures while lowering CO emissions via the regulation of combustion air.

Key words:

, , ,



1733–1742 M. Pexa, J. Čedík, F. Kumhála and R. Pražan
Comparison of mechanical and electric drive of mulcher
Abstract |
Full text PDF (630 KB)

Comparison of mechanical and electric drive of mulcher

M. Pexa¹*, J. Čedík¹, F. Kumhála² and R. Pražan³

¹Czech University of Life Sciences, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamýcká 129, CZ16521, Prague 6, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Agricultural Machines, Kamýcká 129, CZ16521, Prague 6, Czech Republic
³Research Institute of Agriculture Engineering, Drnovská 507, CZ161 01, Prague 6, Czech Republic
*Correspondence: pexa@tf.czu.cz

Abstract:

The contribution is focused on comparison of mechanical and electric drive of mulcher with vertical axis of rotation by means of mathematical model. The mulcher has working width of 6 m and it is usually aggregated with tractor of minimal power of 150 kW. On the test plot the torque and power transferred trough the tractor PTO, fuel consumption and the production of gaseous emissions components were monitored. This field measurement served as a basis for modelling as well as measured complete characteristics of the combustion engine of the tractor John Deere 7930. As a main base for the modelling the record of real operation of the tractor with mulcher was used. Then, in the software product MathCad the operation of the tractor with mechanical and electrical drive of the mulcher was modelled. In the case of the electrical drive of the mulcher the tractor with internal combustion engine, connected to generator was taken into consideration. Due to overall lower efficiency of the electrical drive with generator, worse values of the fuel consumption and emissions production in comparison with mechanical drive were reached in case of electric drive. At hypothetical use of batteries (100% electro-powered tractor) and when the energy mix at Czech Republic is taken into consideration, it is possible to reach the quarter values of emissions production in comparison with combustion engine.

Key words:

, , ,



783–789 P. Jindra, M. Kotek, J. Mařík and M. Vojtíšek
Effect of different biofuels to particulate matters production
Abstract |
Full text PDF (348 KB)

Effect of different biofuels to particulate matters production

P. Jindra¹*, M. Kotek¹, J. Mařík¹ and M. Vojtíšek²

¹Czech University of Life Science Prague, Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ 16521 Prague, Czech republic
²Czech Technical University in Prague, Faculty of Mechanical Engineering, Center of Vehicles for Sustainable Mobility, Technická 4, CZ 16607 Prague, Czech Republic
*Correspondence: jindrap@tf.czu.cz

Abstract:

 In recent years the European Union has exhibited a significant interest in the reduction of crude oil usage. Biofuels can be used in conventional engines but the biofuels should reduce the emissions produced by internal combustion engines. This article deals with analysis of particulate matters (PM) production in chosen biofuels burned in internal combustion engine Zetor 1505. The conventional emission analysers are capable to detect gaseous emission components but they are not able to classify PM. Analysis of PM was performed with a TSI Engine Exhaust Particle Sizer 3090 which is able to classify particles from 5.6 nm to 560 nm. The device analysed different blends of alcohol–based biofuels tested under NRSC cycle conditions. The given size of PM can be taken as an impact on human organism’s cells consequently human health. PM create an ideal medium for polyaromatic hydrocarbons (PAH), their composition and structure. Analysis of PM should become a standard component of every emission parameter assessment.

Key words:

, ,



725–732 D. Černý, J. Malaťák and J. Bradna
Influence of biofuel moisture content on combustion and emission characteristics of stove
Abstract |
Full text PDF (239 KB)

Influence of biofuel moisture content on combustion and emission characteristics of stove

D. Černý*, J. Malaťák and J. Bradna

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ 165 21 Prague, Czech Republic
*Correspondence: david.cerny@dotacenazeleno.cz

Abstract:

 The research aim was to study the effect of moisture in solid fuel on combustion in a stove and its emissions. Analysed samples were from spruce woodchips. Four samples were prepared with different moisture contents and furthermore spruce wood was used as a reference sample. Combustion device used was a stove with a fixed fire grate. Studied parameters were ambient temperature, temperature of flue gases, coefficient of excess air, and contents of oxygen and carbon monoxide in flue gases. Laboratory measurement was performed on an analyser of flue gases whose function is based on electro-chemical converters. Measured values were first converted to a referential oxygen content in flue gases. Evaluation of these values was then made by regression analyses. The course of combustion process and its quality can be seen well in functional dependence of carbon monoxide on excess air coefficient. The area of combustion was the smallest with the least moist sample (3.2%) and increases with increasing moisture. A sample with high moisture (31.1%) was already causing the fire to gradually extinguish. Because flue gas temperature is in the same range for all samples, the overall efficiency of the stove decreases sharply with fuel moisture due to specific heat of flue gases. It has been thus confirmed that fuel moisture content has a substantial influence on combustion, especially in the chosen combustion device, which has been verified by comparison with the reference fuel.

Key words:

, , , ,



540–546 M. Pexa, J. Čedík,, F. Kumhála and R. Pražan
Estimation of mulching energy intensity
Abstract |
Full text PDF (502 KB)

Estimation of mulching energy intensity

M. Pexa¹, J. Čedík,¹*, F. Kumhála² and R. Pražan³

¹Czech University of Life Sciences, Faculty of Engineering, Department for Quality and
Dependability of Machines, Kamycka 129, CZ 165 21 Prague 6, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Agricultural
Machines, Kamycka 129, CZ 165 21 Prague 6, Czech Republic
³Research Institute of Agricultural Engineering, p.r.i., Drnovská 507, CZ 161 01
Prague 6, Czech Republic
*Correspondence: cedikj@tf.czu.cz

Abstract:

Mulching is one of the energy-intensive activities in agriculture. The energy is gained from the consumed fuel. Besides the consumed fuel the combustion engine produces harmful and unharmful exhaust gases. The general trend is to reduce the production of harmful constituents of emissions as well as carbone dioxide. This can be achieved by various construction modifications or additional modifications of exhaust gases. It is possible to estimate the energy intensity in advance by several different ways. The paper presents the estimation based on measured complete characteristics of emissions production and the fuel consumption of used combustion engine and on the measured on-board data. The results show that the estimation of fuel consumption and thus also production of carbon dioxide can be relatively successful. The estimation differs quite significantly for other emissions components. During different transition modes of the combustion engine there is a change of emissions production which is hard to describe. The solution could lie in use of other parameters determining the operation mode of the engine in addition to the commonly used speed and torque of the combustion engine.

Key words:

, , ,



123–133 A. Lēnerts, D. Popluga, K. Naglis-Liepa and P. Rivža
Fertilizer use efficiency impact on GHG emissions in the Latvian crop sector
Abstract |
Full text PDF (348 KB)

Fertilizer use efficiency impact on GHG emissions in the Latvian crop sector

A. Lēnerts¹, D. Popluga¹*, K. Naglis-Liepa¹ and P. Rivža²

¹Latvia University of Agriculture, Faculty of Economics and Social Development,
Institute of Economics and Regional Development, Svetes street 18, LV-3001, Jelgava,
Latvia
²Latvia University of Agriculture, Faculty of Information technologies, Liela street 2,
LV-3001, Jelgava, Latvia
*Correspondence: dina.popluga@llu.lv

Abstract:

Within increasing production activity Latvian agricultural sector has become one of the main sources of greenhouse gas emissions (GHG) in Latvia. In 2013, agricultural sector contributed 21.0% of the total GHG emissions originated in Latvia (2310.1 Gg CO2eq). Analysis of agricultural GHG emissions by sources shows that direct N2O emissions from agricultural soils through the usage of synthetic fertilizers are one of the most significant GHG source in Latvia. The usage of synthetic fertilizers is one of the most common widespread agricultural practices in Latvian cropping systems and according to statistical data usage of synthetic fertilizers is constantly increasing, for example, in 2013 it increased by 6.9% if compared with 2012. Taking into account that over-fertilization can lead to negative economic and environmental consequences, such as high production costs, depletion of energy resources, and increased GHG emissions, this research aims to estimate how effective usage of synthetic fertilizers are in Latvian crop farms. In order to achieve the set aim an N fertilizer usage were estimated in four crop farms by giving insight into N balance and N use efficiency (NUE) rate in these farms. Research results suggest that improved N efficiency can be selected as GHG mitigation measure as it reduces N surpluses and the use and production of mineral fertiliser while maintaining yield levels. It was also concluded that improved N efficiency reduces direct N2O emissions from fertilized soils and indirect N2O emissions that occur by the release of NH3.

Key words:

, , ,