scholarly journals Impact of Ignition Technique on Pollutants Emission during the Combustion of Selected Solid Biofuels

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2664 ◽  
Author(s):  
Artur Kraszkiewicz ◽  
Artur Przywara ◽  
Alexandros Sotirios Anifantis
Keyword(s):  
Fossil Fuels ◽  
Initial Period ◽  
Combustion Process ◽  
Operating Conditions ◽  
So2 Emissions ◽  
Top Down ◽  
Operational Conditions ◽  
Solid Biofuels ◽  
Pollutants Emission ◽  
The Impact

Nowadays, heating using wood, briquettes, or pellets is a curious replacement to fossil fuels such as coal, oil, or gas. Unfortunately, the combustion of biofuels, especially in low-power boilers with unstable operating conditions, releases a lot of gas pollutants (e.g., carbon monoxide (CO), nitric oxide (NO), and various organic compounds) that are usually generated due to the incomplete product combustion. The combustion of biofuel in grate boilers with top-down ignition is a new approach, popular in society (mainly used for coal fuels), which improves the combustion process and reduces the amount of pollutants emitted. This study evaluated the impact of ignition techniques on the emission level of gas pollutants during the combustion of wood logs, briquettes, and pellets of pine in grate-based charging boilers. The combination of top ignition mode with pinewood logs allowed us to achieve a reduction of 6% in CO and sulfur dioxide (SO2) emission into the atmosphere. However, the combination of top-down ignition mode with pellets and briquettes produced, in fully operational conditions, 1- to 18-fold higher levels of CO and SO2 respectively, than bottom-up ignition, after an initial period of low level CO and SO2 emissions. During the tests (mainly with ignition from top), substantial emissions of NO were observed of up to 400 mg·m−3 at 10% O2. Therefore, further research is required to decrease emission related to the content of nitrogen in biomass. In this respect, research of impact on the combustion temperature of such emissions is needed.

scholarly journals Performance analysis of the working surface of the rails from test batches on the Test Loop of JSC “VNIIZhT”

2018 ◽  
Vol 77 (3) ◽  
pp. 141-148
Author(s):  
M. Yu. Khvostik ◽  
I. V. Khromov ◽  
O. A. Bykova ◽  
G. A. Beresten’
Keyword(s):  
Wear Resistance ◽  
Operating Time ◽  
Operating Conditions ◽  
Continuous Change ◽  
Wear Area ◽  
Railway Network ◽  
Operational Conditions ◽  
Rolling Surface ◽  
Test Loop ◽  
The Impact

The monitoring of railway rails damage on the railway network of the JSC “Russian Railways” as well as operational and polygon tests are conducted with the purpose of assessing the impact of operating conditions on the intensity of rails damage, obtaining initial data for forecasting rails failures. The increased intensity of rails wear on sites with a complex plan and profile leads to the fact that with a continuous change from the track, rails which have an underutilized service life of more than 20 % are retrieved. Polygon tests on the Test Loop of the JSC “VNIIZhT” near the Scherbinka station can provide the repeatability and reliability of the results, comparative tests are carried out under identical conditions and their duration is several times less than when tested at experimental sites under operational conditions. The results of the polygon tests of new differentially heat-strengthened rails did not reveal any advantages in the wear resistance of special purposed rails (laid in the recommended radius of the curve for its application) when comparing the rails of domestic manufacturers. Metal shelling out on the rolling surface of rails is the main reason for the removal of rails from test batches. The origin and development of defects of this kind is due to both violations of the technology of manufacturing rails, and because of violations of the current maintenance of the track. The metal stock in the area of the rail head of R65 type due to the increase in its dimensions positively affects the extension of the lifetime of the rails, reducing the cost of the life cycle and the rail itself, and the design of the track as a whole. When carrying out a separate study in order to obtain results characterizing the stability of high-quality rails to contact fatigue damage, it is advisable to optimize the conditions of the polygon tests, bringing them closer to operational ones. When forming the test results, it is necessary to expand the list of criteria for assessing the wear resistance of rails, supplementing it with the size of the wear area at the time of a certain operating time of the tonnage, with the introduction of this criterion into the appropriate methods for the polygon (operational) tests.

A comparative study of the effect of compression ratio on the efficiency and flame development angle in a Cooperative Fuel Research engine fueled with binary gasoline–alcohol blends

2019 ◽  
pp. 146808741985910 ◽  
Author(s):  
Guillermo Rubio-Gómez ◽  
Lis Corral-Gómez ◽  
David Rodriguez-Rosa ◽  
Fausto A Sánchez-Cruz ◽  
Simón Martínez-Martínez
Keyword(s):  
Comparative Study ◽  
Compression Ratio ◽  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Fossil Fuels ◽  
Combustion Process ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Flame Development ◽  
The Impact

In the last few years, increasing concern about the harmful effects of the use of fossil fuels in internal combustion engines has been observed. In addition, the limited availability of crude oil has driven the interest in alternative fuels, especially biofuels. In the context of spark ignition engines, bioalcohols are of great interest owing to their similarities and blend capacities with gasoline. Methanol and ethanol have been widely used, mainly due to their knocking resistance. Another alcohol of great interest is butanol, thanks to its potential of being produced as biofuel and its heat value closer to gasoline. In this study, a comparative study of gasoline–alcohol blend combustion, with up to 20% volume, with neat gasoline has been carried out. A single-cylinder, variable compression ratio, Cooperative Fuel Research-type spark ignition engine has been employed. The comparison is made in terms of fuel conversion efficiency and flame development angle. Relevant information related to the impact in the combustion process of the use of the three main alcohols used in blends with gasoline has been obtained.

Effects of dual biofuel approach for total elimination of diesel on injection system by reciprocatory friction monitor

2017 ◽  
Vol 232 (9) ◽  
pp. 1068-1076 ◽  
Author(s):  
Paramvir Singh ◽  
Varun Goel ◽  
SR Chauhan
Keyword(s):  
Diesel Engine ◽  
Fossil Fuels ◽  
Operating Conditions ◽  
Injection System ◽  
Effect Of Temperature ◽  
Compression Ignition ◽  
Oil Blends ◽  
Compression Ignition Engines ◽  
The Impact ◽  
Total Elimination

Biodiesel is a promising fuel which shows potential and gradually received attention as a best alternate feedstock for diesel engine. Previous investigations have shown that use of double biofuels in a diesel engine can be a promising aspect for complete elimination of diesel from compression ignition engines which will decrease our dependency on fossil fuels. The tribological performance of injection system is primarily based on the lubricity characteristics of the fuel. So, it is imperative to a more diversified research about the impact of using double biofuels in engine. In the present investigation, different biodiesel-oil blends were investigated using the ASTM D6079 by the reciprocatory friction monitor. The effect of temperature variation on lubricity characteristics was also studied. The biodiesel-oil blends shows improvement in results as compared to diesel. Biodiesel is prone to oxidation due to availability of unsaturation in their moieties. The effects of oxidation on lubricity characteristics were also studied. It was also found that the operating conditions collectively affected the lubricity characteristics of tested feedstocks.

Numerical and Experimental Investigation on an Effusion-Cooled Lean Burn Aeronautical Combustor: Aerothermal Field and Emissions

2018 ◽  
Vol 141 (4) ◽  
Author(s):  
L. Mazzei ◽  
S. Puggelli ◽  
D. Bertini ◽  
A. Andreini ◽  
B. Facchini ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Combustion Process ◽  
Operating Conditions ◽  
Pollutant Emissions ◽  
Flame Spray ◽  
Distribution Factor ◽  
Lean Burn ◽  
Radial Temperature ◽  
Flamelet Generated Manifold ◽  
The Impact

Lean burn combustion is increasing its popularity in the aeronautical framework due to its potential in reducing drastically pollutant emissions (NOx and soot in particular). Its implementation, however, involves significant issues related to the increased amount of air dedicated to the combustion process, demanding the redesign of injection and cooling systems. Also, the conditions at the combustor exit are a concern, as high turbulence, residual swirl, and the impossibility to adjust the temperature profile with dilution holes determine a harsher environment for nozzle guide vanes. This work describes the final stages of the design of an aeronautical effusion-cooled lean burn combustor. Full annular tests were carried out to measure temperature profiles and emissions (CO and NOx) at the combustor exit. Different operating conditions of the ICAO cycle were tested, considering Idle, Cruise, Approach, and Take-off. Scale-adaptive simulations with the flamelet generated manifold (FGM) combustion model were performed to extend the validation of the employed computational fluid dynamics (CFD) methodology and to reproduce the experimental data in terms of radial temperature distribution factor (RTDF)/overall temperature distribution factor (OTDF) profiles as well as emission indexes (EIs). The satisfactory agreement paved the way to an exploitation of the methodology to provide a deeper understanding of the flow physics within the combustion chamber, highlighting the impact of the different operating conditions on flame, spray evolution, and pollutant formation.

scholarly journals Determining air pollutant emission rates based on mass balance using airborne measurement data over the Alberta oil sands operations

2015 ◽  
Vol 8 (5) ◽  
pp. 4769-4816 ◽  
Author(s):  
M. Gordon ◽  
S.-M. Li ◽  
R. Staebler ◽  
A. Darlington ◽  
K. Hayden ◽  
...  
Keyword(s):  
Oil Sands ◽  
Air Pollutant ◽  
Operating Conditions ◽  
Pollutant Emission ◽  
Retrieval Algorithm ◽  
Emission Rates ◽  
So2 Emissions ◽  
Top Down ◽  
Implementation Plan ◽  
Bottom Up

Abstract. Top-down approaches to measure total integrated emissions provide verification of bottom-up, temporally-resolved, inventory-based estimations. Aircraft-based measurements of air pollutants from sources in the Canadian oil sands were made in support of the Joint Canada–Alberta Implementation Plan on Oil Sands Monitoring during a summer intensive field campaign between 13 August and 7 September 2013. The measurements contribute to knowledge needed in support of the Joint Canada–Alberta Implementation Plan on Oil Sands Monitoring. This paper describes a Top-down Emission Rate Retrieval Algorithm (TERRA) to determine facility emissions of pollutants, using SO2 and CH4 as examples, based on the aircraft measurements. In this algorithm, the flight path around a facility at multiple heights is mapped to a two-dimensional vertical screen surrounding the facility. The total transport of SO2 and CH4 through this screen is calculated using aircraft wind measurements, and facility emissions are then calculated based on the divergence theorem with estimations of box-top losses, horizontal and vertical turbulent fluxes, surface deposition, and apparent losses due to air densification and chemical reaction. Example calculations for two separate flights are presented. During an upset condition of SO2 emissions on one day, these calculations are within 5% of the industry-reported, bottom-up measurements. During a return to normal operating conditions, the SO2 emissions are within 11% of industry-reported, bottom-up measurements. CH4 emissions calculated with the algorithm are relatively constant within the range of uncertainties. Uncertainty of the emission rates is estimated as 20%, which is primarily due to the unknown SO2 and CH4 mixing ratios near the surface below the lowest flight level.

scholarly journals Application of Data Validation and Reconciliation to Improve Measurement Results in the Determination Process of Emission Characteristics in Co-Combustion of Sewage Sludge with Coal

2021 ◽  
Vol 13 (9) ◽  
pp. 5300
Author(s):  
Michał Kozioł ◽  
Joachim Kozioł
Keyword(s):  
Sewage Sludge ◽  
Fossil Fuels ◽  
Combustion Process ◽  
Emission Characteristics ◽  
Gaseous Emissions ◽  
Data Validation ◽  
Measurement Instruments ◽  
Operational Conditions ◽  
Air Stream ◽  
Improve Measurement

One of the actions popularized worldwide to reduce the consumption of fossil fuels is the combustion of renewable fuels and the co-combustion of both of these fuels. To properly implement combustion and co-combustion processes in power-generation installations, operational characteristics, including emission characteristics are required. To determine these characteristics, tests must be conducted, within the scope of which, for individual operating stages of the installation’s work, the readings collected from a relatively large number of control and measurement instruments should be taken into account. All these instruments have different levels of accuracy, which, among other factors, bring about lower adequacy of the characteristics determined on the basis of these measurements. The objective of this study is to present possible adaptations of data validation and reconciliation methods to increase the adequacy of emission characteristics for the process of co-combustion of fuels. The methodology is discussed based on the example of studies on the co-combustion process of sewage sludge with coal in a grate furnace. The aforementioned characteristics were determined based on measurement tests of gaseous emissions of flue gas components. The tests were carried out for various preset operational conditions of the process, such as the thickness of fuel layer on the grate, the share of sludge in the fuel, the humidity of the sludge, the theoretical ratio of excess air to combustion, and the distribution of air stream during the process. The research object is described and detailed research results concerning two exemplary measurement tests are given, as well as the most important results referring to the whole research. The performed calculations indicate the necessity to take into account often significant corrections, which can amount to about 10% of the measured value.

Numerical and Experimental Investigation on an Effusion-Cooled Lean Burn Aeronautical Combustor: Aerothermal Field and Emissions

2018 ◽  
Author(s):  
L. Mazzei ◽  
S. Puggelli ◽  
D. Bertini ◽  
A. Andreini ◽  
B. Facchini ◽  
...  
Keyword(s):  
Combustion Process ◽  
Operating Conditions ◽  
Pollutant Emissions ◽  
Combustion Model ◽  
Flame Spray ◽  
Lean Burn ◽  
Flamelet Generated Manifold ◽  
Nozzle Guide ◽  
Nozzle Guide Vanes ◽  
The Impact

Lean burn combustion is increasing its popularity in the aeronautical framework due to its potential in reducing drastically pollutant emissions (NOx and soot in particular). Its implementation however involves significant issues related to the increased amount of air dedicated to the combustion process, demanding the redesign of injection and cooling systems. Also the conditions at the combustor exit are a concern, as high turbulence, residual swirl and the impossibility to adjust the temperature profile with dilution holes determine a harsher environment for nozzle guide vanes. This work describes the final stages of the design of an aeronautical effusion-cooled lean burn combustor. Full annular tests were carried out to measure temperature profiles and emissions (CO and NOx) at the combustor exit. Different operating conditions of the ICAO cycle were tested, considering Idle, Cruise, Approach and Take-Off. Scale-adaptive simulations with the Flamelet Generated Manifold combustion model were performed to extend the validation of the employed CFD methodology and to reproduce the experimental data in terms of RTDF/OTDF profiles as well as emission indexes. The satisfactory agreement paved the way to an exploitation of the methodology to provide a deeper understanding of the flow physics within the combustion chamber, highlighting the impact of the different operating conditions on flame, spray evolution and pollutant formation.

scholarly journals Methodological Approach for 1D Simulation of Port Water Injection for Knock Mitigation in a Turbocharged DISI Engine

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4297
Author(s):  
Federico Millo ◽  
Fabrizio Gullino ◽  
Luciano Rolando
Keyword(s):  
Film Formation ◽  
Methodological Approach ◽  
Direct Injection ◽  
Water Injection ◽  
Combustion Process ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Transient Phenomena ◽  
Wall Film ◽  
The Impact

In the upcoming years, more challenging CO2 emission targets along with the introduction of more severe Real Driving Emissions limits are expected to foster the development and the exploitation of innovative technologies to further improve the efficiency of automotive Spark Ignition (SI) engines. Among these technologies, Water Injection (WI), thanks to its knock mitigation capabilities, can represent a valuable solution, although it may significantly increase the complexity of engine design and calibration. Since, to tackle such a complexity, reliable virtual development tools seem to be mandatory, this paper aims to describe a quasi-dimensional approach to model a Port Water Injection (PWI) system integrated in a Turbocharged Direct Injection Spark Ignition (T-DISI) engine. Through a port-puddling model calibrated with 3D-CFD data, the proposed methodology was proven to be able to properly replicate transient phenomena of water wall film formation, catching cycle by cycle the amount of water that enters into the cylinder and is therefore available for knock mitigation. Moreover, when compared with experimental measurements under steady state operating conditions, this method showed good capabilities to predict the impact of the water content on the combustion process and on the knock occurrence likelihood.

scholarly journals Determining air pollutant emission rates based on mass balance using airborne measurement data over the Alberta oil sands operations

2015 ◽  
Vol 8 (9) ◽  
pp. 3745-3765 ◽  
Author(s):  
M. Gordon ◽  
S.-M. Li ◽  
R. Staebler ◽  
A. Darlington ◽  
K. Hayden ◽  
...  
Keyword(s):  
Oil Sands ◽  
Air Pollutant ◽  
Operating Conditions ◽  
Pollutant Emission ◽  
Retrieval Algorithm ◽  
Emission Rates ◽  
So2 Emissions ◽  
Top Down ◽  
Implementation Plan ◽  
Bottom Up

Abstract. Top-down approaches to measure total integrated emissions provide verification of bottom-up, temporally resolved, inventory-based estimations. Aircraft-based measurements of air pollutants from sources in the Canadian oil sands were made in support of the Joint Canada–Alberta Implementation Plan for Oil Sands Monitoring during a summer intensive field campaign between 13 August and 7 September 2013. The measurements contribute to knowledge needed in support of the Joint Canada–Alberta Implementation Plan for Oil Sands Monitoring. This paper describes the top-down emission rate retrieval algorithm (TERRA) to determine facility emissions of pollutants, using SO2 and CH4 as examples, based on the aircraft measurements. In this algorithm, the flight path around a facility at multiple heights is mapped to a two-dimensional vertical screen surrounding the facility. The total transport of SO2 and CH4 through this screen is calculated using aircraft wind measurements, and facility emissions are then calculated based on the divergence theorem with estimations of box-top losses, horizontal and vertical turbulent fluxes, surface deposition, and apparent losses due to air densification and chemical reaction. Example calculations for two separate flights are presented. During an upset condition of SO2 emissions on one day, these calculations are within 5 % of the industry-reported, bottom-up measurements. During a return to normal operating conditions, the SO2 emissions are within 11 % of industry-reported, bottom-up measurements. CH4 emissions calculated with the algorithm are relatively constant within the range of uncertainties. Uncertainty of the emission rates is estimated as less than 30 %, which is primarily due to the unknown SO2 and CH4 mixing ratios near the surface below the lowest flight level.

scholarly journals Assessment of the Performance of Alternative Aviation Fuel in a Modern Air-Spray Combustor (MAC)

2008 ◽  
Author(s):  
I. Uryga-Bugajska ◽  
M. Pourkashanian ◽  
D. Borman ◽  
E. Catalanotti ◽  
L. Ma ◽  
...  
Keyword(s):  
Mixture Fraction ◽  
Combustion Process ◽  
Oxidation Mechanism ◽  
Design Tool ◽  
Operating Conditions ◽  
Aviation Fuel ◽  
Substantial Part ◽  
Chemical Difference ◽  
Blended Fuel ◽  
The Impact

Recent concerns over energy security and environmental considerations have highlighted the importance of finding alternative aviation fuels. It is expected that coal and biomass derived fuels will fulfil a substantial part of these energy requirements. However, because of the physical and chemical difference in the composition of these fuels, there are potential problems associated with the efficiency and the emissions of the combustion process. Over the past 25 years Computational Fluid Dynamics (CFD) has become increasingly popular with the gas turbine industry as a design tool for establishing and optimising key parameters of systems prior to starting expensive trials. In this paper the performance of a typical aviation fuel, kerosene, an alternative aviation fuel, biofuel and a blend have been examined using CFD modelling. A comprehensive understanding of the kinetics of the reaction for bio aviation fuels at both high and low temperature is necessary to perform reliable simulations of ignition, combustion and emissions in an aero-engine. A novel detailed reaction mechanism was used to represent the aviation fuel oxidation mechanism. The fuel combustion is calculated using a 3D commercial solver using a mixture fraction/pdf approach. Firstly, the study demonstrates that CFD predictions compare favourably with experimental data obtained by QinetiQ for a Modern Airspray Combustor (MAC) when used with traditional jet fuel (kerosene). Furthermore, the 3D CFD model has been refined to use the laminar flamelet model (LFM) approach that incorporates recently developed chemical reaction mechanisms for the bio-aviation fuel. This has enabled predictions for the bio-aviation fuel to be made. The impact of using the blended fuel has been shown to be very similar in performance to that of the 100% kerosene, confirming that aircraft running on 20% blended fuel should have no significant reduction in performance. It was also found that for the given operating conditions there is a significant reduction in performance when 100% biofuel is used. Additionally, interesting predictions were obtained, related to NOx emissions for the blend and 100% biofuel.

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