scholarly journals Optimization of Ship Propulsion Diesel Engine to Fulfill the New Requirements for Exhaust Emissions

2014 ◽  
Vol 3 (1) ◽  
pp. 20-31
Author(s):  
Branko Lalić ◽  
Ivan Komar ◽  
Danilo Nikolić

Impacts of exhaust gas emissions on the environment and air pollution from ships have received considerable attention in the past few decades. Due to the characteristics of the combustion process, typical for large marine two-stroke low-speed engines, and the use of residual fossil fuels, the world’s fleet emits into the atmosphere significant amount of pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO2), hydrocarbons (HC), sulphur oxides (SOx) and carbon particles (PM). Impact assessment of the process of their formation, emitted amounts and the influence of emission are important factors for decision making in regulation development and also for engine designers who aim to improve low-speed two-stroke marine engines, for further tightening of regulations regarding limiting emissions. This paper consists of three parts: the first section describes the injection and combustion process in lowspeed two-stroke marine engines, the second part describes the formation of the exhaust as emissions as a product of the combustion process and the third part, in which the known techniques to reduce harmful emissions that are currently used in low-speed two-stroke marine engines are described.

2014 ◽  
Vol 13 (2) ◽  
pp. 5-17
Author(s):  
Agnieszka Bok ◽  
Joanna Guziałowska-Tic ◽  
Wilhelm Jan Tic

Abstract The dynamic growth of the use of non-renewable fuels for energy purposes results in demand for catalysts to improve their combustion process. The paper describes catalysts used mainly in the processes of combustion of motor fuels and fuel oils. These catalysts make it possible to raise the efficiency of oxidation processes simultanously reducing the emission of pollutants. The key to success is the selection of catalyst compounds that will reduce harmful emissions of combustion products into the atmosphere. Catalysts are introduced into the combustion zone in form of solutions miscible with fuel or with air supplied to the combustion process. The following compounds soluble in fuel are inclused in the composition of the described catalysts: organometallic complexes, manganese compounds, salts originated from organic acids, ferrocen and its derivatives and sodium chloride and magnesium chloride responsible for burning the soot (chlorides). The priority is to minimize emissions of volatile organic compounds, nitrogen oxides, sulphur oxides, and carbon monoxide, as well as particulate matter.


Author(s):  
YANTI SUPRIANTI

ABSTRAKPemerintah menargetkan peningkatan peran energi terbarukanhingga mencapai 24% pada tahun 2050. Biogas sebagai salah satu dari sumber energi terbarukan harus memiliki nilai kalor yang memadaiagar dapat bersaing dengan sumber energi fosil. Zat yang memiliki kontribusi terbesar dalam menentukan nilai kalor biogas adalah Metana (CH4). Namun, biogas juga memiliki kandungan Karbon dioksida (CO2) yang bersifat tidak terbakar. Upaya untuk meningkatkan nilai kalor biogas dapat ditempuh dengan menurunkan kandungan CO2, salah satunya melalui proses adsorpsi. Penelitian ini menggunakan kolom adsorpsi seri berukuran 2,43 L untuk meningkatkan waktu kontak antara adsorben karbon aktif dengan gas-gas kontaminan. Hasil penelitian menunjukkan bahwa kandungan CO2 dapat ditekan hingga di bawah 14% pada waktu adsorpsi 10 menit,dan diperoleh kandungan CH4 hingga minimal 78,73%. Hasil optimum kinerja kolom adsorpsi seri yaitu pada laju alir 2,4 L/menit dan waktu adsorpsi 10 menit, mampu memurnikan biogas hingga mengandung CH4 91,60%. Pada kondisi optimum tersebut, efektifitas kolom adsorpsi adalah sebesar 98,31%.Kata kunci: biogas, pemurnian, karbon aktif, waktu adsorpsi, efektifitas kolom adsorpsi.ABSTRACTIndonesian government had targettedthe role of renewable energy, up to 24% in 2050. Biogas, as one of renewable energy, should have sufficient calorific valuein order to be efficiently used and competitive compared to fossil fuels. Methane (CH4) in biogas is the most important substance that determine biogas calorific value. On the other hand, another component of biogas, Carbon dioxide (CO2), the one that inhibit combustion process must be reduced. One of the methods to reduce CO2 content can be conducted through adsorption process. This research utilized serial adsorption column to increase contact between activated carbon as adsorbent and contaminant gases. The result showed that CO2 content can be suppressed below 14% in 10 minutes adsorption time, so that CH4 content can be upgraded above 78.73%. The optimum performance of serial adsorption column obtained at 2.4 lpm of biogas flow in 10 minutes adsorption time, able to purify biogas to 91.60% of CH4 content. In optimum condition, serial adsorption column effectiveness was 98.31%.Keywords: biogas, purification, activated carbon, adsorption time, serial adsorption column effectiveness.


Author(s):  
Kartika Srivastava

Abstract: Carbon dioxide capture and sequestration (CCS) is the capture and storage of carbon dioxide (CO2) that is emitted to the atmosphere as a result of combustion process. Presently majority of efforts focus on the removal of carbon dioxide directly from industrial plants and thereby storing it in geological reservoirs. The principle is to achieve a carbon neutral budget if not carbon negative, and thereby mitigate global climate change. Currently, fossil fuels are the predominant source of the global energy generation and the trend will continue for the rest of the century. Fossil fuels supply over 63% of all primary energy; the rest is contributed by nuclear, hydro-electricity and renewable energy. Although research and investments are being targeted to increase the percentage of renewable energy and foster conservation and efficiency improvements of fossil-fuel usage, development of CCS technology is the most important tool likely to play a pivotal role in addressing this crisis. [1] Keywords: Carbon Capture and Storage, Carbon dioxide, fossil fuels, Greenhouse gases


2013 ◽  
pp. 109-128 ◽  
Author(s):  
C. Rühl

This paper presents the highlights of the third annual edition of the BP Energy Outlook, which sets out BP’s view of the most likely developments in global energy markets to 2030, based on up-to-date analysis and taking into account developments of the past year. The Outlook’s overall expectation for growth in global energy demand is to be 36% higher in 2030 than in 2011 and almost all the growth coming from emerging economies. It also reflects shifting expectations of the pattern of supply, with unconventional sources — shale gas and tight oil together with heavy oil and biofuels — playing an increasingly important role and, in particular, transforming the energy balance of the US. While the fuel mix is evolving, fossil fuels will continue to be dominant. Oil, gas and coal are expected to converge on market shares of around 26—28% each by 2030, and non-fossil fuels — nuclear, hydro and renewables — on a share of around 6—7% each. By 2030, increasing production and moderating demand will result in the US being 99% self-sufficient in net energy. Meanwhile, with continuing steep economic growth, major emerging economies such as China and India will become increasingly reliant on energy imports. These shifts will have major impacts on trade balances.


2017 ◽  
Vol 68 (11) ◽  
pp. 2676-2681
Author(s):  
Mihaela Gabriela Dumitru ◽  
Dragos Tutunea

The purpose of this work was to investigate the physicochemical properties of watermelon seeds and oil and to find out if this oil is suitable and compatible with diesel engines. The results showed that the watermelon seeds had the maximum length (9.08 mm), width (5.71mm), thickness (2.0 mm), arithmetic mean diameter (5.59 mm), geometrical mean diameter (4.69 mm), sphericity (51.6%), surface area (69.07), volume 0.17 cm3 and moisture content 5.4%. The oil was liquid at room temperature, with a density and refractive index of 0.945 and 1.4731 respectively acidity value (1.9 mgNaOH/g), free fatty acid (0.95 mgNaOH), iodine value (120 mgI2/100g), saponification value (180 mgKOH/g), antiradical activity (46%), peroxide value (7.5 mEqO2/Kg), induction period (6.2 h), fatty acid: palmitic acid (13.1%), stearic acid (9.5 %), oleic acid (15.2 %) and linoleic acid (61.3%). Straight non food vegetable oils can offer a solution to fossil fuels by a cleaner burning with minimal adaptation of the engine. A single cylinder air cooled diesel engine Ruggerini RY 50 was used to measure emissions of various blends of watermelon oil (WO) and diesel fuel (WO10D90, WO20D80, WO30D70 and WO75D25). The physic-chemical properties of the oil influence the combustion process and emissions leading to the reduction of NOX and the increase in CO, CO2 and HC.


2021 ◽  
Author(s):  
Wenzhang Li ◽  
Keke Wang ◽  
yanfang Ma ◽  
Yang Liu ◽  
Weixin Qiu ◽  
...  

The ever-growing factitious over-consumption of fossil fuels and the accompanying massive emissions of CO2 have caused severe energy crisis and environmental issues. Photoelectrochemical (PEC) reduction of CO2 that can combine...


2009 ◽  
Vol 131 (4) ◽  
Author(s):  
F. Ochs ◽  
W. Heidemann ◽  
H. Müller-Steinhagen

More than 30 international research and pilot seasonal thermal energy stores (TESs) were realized within the past 30 years. Experiences with operation of these systems show that TES are technically feasible and work well. Seasonal storage of solar thermal energy or of waste heat from heat and power cogeneration plants can significantly contribute to substitute fossil fuels in future energy systems. However, performance with respect to thermal losses and lifetime has to be enhanced, while construction costs have to be further reduced. This paper gives an overview about the state-of-the-art of seasonal thermal energy storage with the focus on tank and pit TES construction. Aspects of TES modeling are given. Based on modeled and measured data, the influence of construction type, system configuration, and boundary conditions on thermal losses of large-scale TES is identified. The focus is on large-scale applications with tank and pit thermal energy stores and on recent investigations on suitable materials and constructions. Furthermore, experiences with the operation of these systems with respect to storage performance are discussed.


Nanoscale ◽  
2022 ◽  
Author(s):  
Meiqiu Xie ◽  
Xuhai Liu ◽  
Yang Li ◽  
Xing'ao Li

The past several years have witnessed remarkable research efforts to develop high-performance photovoltaics (PVs), to curtail energy crisis by avoiding dependence on traditional fossil fuels. In this regard, it is...


Author(s):  
Leezna Saleem ◽  
Imran Ahmad Siddiqui ◽  
Intikhab Ulfat

Pakistan is the world's sixth most populous country, currently facing the worst energy crisis. Although rich in renewable resources, Pakistan's energy system relies mainly on fossil fuels and imported energy for its energy needs. This study aims to use an analytical hierarchy pro-cess to prioritize six renewable technologies for Pakistan, with four criteria and thirteen subcriteria. The results indicate that solar power is particularly well suited for Pakistan, as it gained 42% priority weightage in the final aggregation. Wind energy is ranked second with a priority weight of 24%, followed by hydro 13%, biomass 9%, ocean 8% and geothermal en-ergy 3%. Solar and wind energies accounted for nearly 66% of the total weightage. This result highlighted the significance of economic criteria for the selection of renewable technologies in Pakistan, with around 43% priority weightage. Environmental criteria gained 19% whereas socio-political criteria registered 14% and technical criteria 23% priority weightage. During the potential assessment of the research, it was concluded that although renewable resource development has not been allocated sufficient attention in Pakistan in the past, if the correct decisions are taken regarding the exploitation of these resources, this can remedy the country's hazardous dependence on fossil fuel and imported energy.


Sign in / Sign up

Export Citation Format

Share Document