The impact of the metallic modifiers on the ecological and economic efficiency of the heavy fuel oils combustion process

2020 ◽  
Vol 273 ◽  
pp. 123137
Author(s):  
Wilhelm Jan Tic ◽  
Joanna Guziałowska-Tic
Keyword(s):  
Economic Efficiency ◽  
Combustion Process ◽  
Fuel Oils ◽  
Heavy Fuel Oils ◽  
The Impact

scholarly journals Long-Range Transport of Sulfur Dioxide Emissions From External Sources to Tehran

2021 ◽  
Author(s):  
Reza Bashiri Khuzestani ◽  
Ahmad Taheri ◽  
Bijan Yeganeh
Keyword(s):  
Sulfur Dioxide ◽  
Power Plants ◽  
Large Scale ◽  
Thermal Power ◽  
Emission Sources ◽  
Emission Data ◽  
Regulatory Strategies ◽  
Fuel Oils ◽  
Heavy Fuel Oils ◽  
The Impact

Abstract Large-scale emissions of sulfur dioxide (SO2) from the combustion of heavy fuel oils are deteriorating the air quality in Tehran and regularly causing complex atmospheric pollution situations and human health concerns. Our analysis of the long-term SO2 emission data in Tehran confirmed that the magnitude of local SO2 emission sources is not adequate to reach SO2 concentrations to their present levels. Tehran is predominantly affected by regional transport of SO2 from exterior sources further away located in Iraq, Saudi Arabia, and adjacent provinces neighboring Tehran. Approximately 80% of total SO2 emissions in Tehran were observed to have impacts from the external hotspots outside of Tehran. While local emission sources only contribute around 20% of the total SO2 emissions. Bivariate polar plots, k-mean cluster, pairwise polar correlation, and PSCF analysis provided evidence for the impact of large-scale transport of SO2 emissions from external locations from the west/northwest, north/northeast, and south/southwestern areas of the region. Further observations of these hotspot areas observed in our analysis with TROPOMI satellite data confirmed significant SO2 emissions resulting from the consumption of heavy fuel oils in thermal power plants and oil/gas refineries. Overall, the results suggested that the regulatory strategies for controlling local traffic emissions of SO2 in Tehran would not be beneficial for reducing public health exposures to SO2 in Tehran. Such improvements can be attained mainly by diminishing the emission sources located further away from Tehran.

scholarly journals Comprehensive Thermodynamic Analysis of the Humphrey Cycle for Gas Turbines with Pressure Gain Combustion

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3521 ◽  
Author(s):  
Panagiotis Stathopoulos
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Combustion Process ◽  
Ideal Gas ◽  
Point Of View ◽  
Pressure Gain Combustion ◽  
Combustion Technology ◽  
Secondary Air ◽  
And Performance ◽  
The Impact

Conventional gas turbines are approaching their efficiency limits and performance gains are becoming increasingly difficult to achieve. Pressure Gain Combustion (PGC) has emerged as a very promising technology in this respect, due to the higher thermal efficiency of the respective ideal gas turbine thermodynamic cycles. Up to date, only very simplified models of open cycle gas turbines with pressure gain combustion have been considered. However, the integration of a fundamentally different combustion technology will be inherently connected with additional losses. Entropy generation in the combustion process, combustor inlet pressure loss (a central issue for pressure gain combustors), and the impact of PGC on the secondary air system (especially blade cooling) are all very important parameters that have been neglected. The current work uses the Humphrey cycle in an attempt to address all these issues in order to provide gas turbine component designers with benchmark efficiency values for individual components of gas turbines with PGC. The analysis concludes with some recommendations for the best strategy to integrate turbine expanders with PGC combustors. This is done from a purely thermodynamic point of view, again with the goal to deliver design benchmark values for a more realistic interpretation of the cycle.

scholarly journals Effects of Catalysts on Emissions of Pollutants from Combustion Processes of Liquid Fuels

2014 ◽  
Vol 13 (2) ◽  
pp. 5-17
Author(s):  
Agnieszka Bok ◽  
Joanna Guziałowska-Tic ◽  
Wilhelm Jan Tic
Keyword(s):  
Combustion Process ◽  
Combustion Products ◽  
Organometallic Complexes ◽  
Liquid Fuels ◽  
Motor Fuels ◽  
Harmful Emissions ◽  
Fuel Oils ◽  
Sulphur Oxides ◽  
Dynamic Growth ◽  
Combustion Processes

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.

Reduction of Fuel Utilization Through Oxygen-Enriched Combustion in a Reheat Furnace Pusher-Type

2021 ◽  
Author(s):  
Francisco J. Martinez Zambrano ◽  
Armin K. Silaen ◽  
Kelly Tian ◽  
Joe Maiolo ◽  
Chenn Zhou
Keyword(s):  
Heat Flux ◽  
Fuel Injection ◽  
Combustion Process ◽  
Oxygen Enrichment ◽  
Rolling Temperature ◽  
Heating Zone ◽  
Reheat Furnace ◽  
Steel Slabs ◽  
The Impact ◽  
Reheating Process

Abstract Steelmaking is an energy-intensive process. Thus, energy efficiency is highly important. Several stages of steelmaking involve combustion processes. One of the most energy-consuming processes in steelmaking is the slab reheating process in a reheat furnace (RF). The energy released by fuel combustion is used to heat steel slabs to their proper hot-rolling temperature. The steel slabs move through the reheat furnace passing the three stages of heating called: Preheating Zone (PZ), Heating Zone (HZ), and Soaking Zone (SZ) to finally leave the discharge door at a rolling temperature of 2375 °F. One way to improve a reheat furnace’s fuel consumption is by implementing oxygen-enriched combustion. This study investigates the implementation of oxygen-enriched combustion in a pusher-type reheat furnace. The increment of oxygen in the combustion process allows for increasing the furnace gas temperature. Consequently, the oxygen enrichment approach allows for the reduction of fuel injection. The principal goal of this investigation is to model the combustion-based on oxygen-enrichment and develop parametric studies of fuel injection rates. The different simulations aim to match the slab heat flux profile of the industrial reheat furnace pusher-type. Computational fluid dynamics are used to generate the slab heat flux distribution. To reach more uniform slab heating, oxygen and fuel ports were alternated. Also, injection angles were modified to optimize slab heating and avoid the impact of hot spots. Thermocouple readings of the industrial reheat furnace are compared to simulation results. The results determined that 40–45% fuel reduction can be achieved.

scholarly journals Impact of Irrigation Ecology on Rice Production Efficiency in Ghana

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
John Kanburi Bidzakin ◽  
Simon C. Fialor ◽  
Dadson Awunyo-Vitor ◽  
Iddrisu Yahaya
Keyword(s):  
Economic Efficiency ◽  
Production Efficiency ◽  
Positive Impact ◽  
Stochastic Frontier ◽  
Allocative Efficiency ◽  
Rice Production ◽  
Cross Sectional ◽  
Rice Farmers ◽  
Effect Regression ◽  
The Impact

Irrigation production is a means by which agricultural production can be increased to meet the growing food demands in the world. This study evaluated the effect of irrigation ecology on farm household technical, allocative, and economic efficiency of smallholder rice farmers. Cross-sectional data was obtained from 350 rice farmers across rain fed and irrigation ecologies. Stochastic frontier analyses are used to estimate the production efficiency and endogenous treatment effect regression model is used to estimate the impact of irrigation ecology on rice production efficiency. The impact of irrigation ecology on technical efficiency is about 0.05, which implies farmers producing under irrigation ecology are more technically efficient in their rice production than those in rain fed production. The impact of irrigation ecology on allocative efficiency is about 0.33, which shows that farmers participating in irrigation farming are more allocatively efficient in their rice production than those in rain fed production. The impact on economic efficiency is about 0.23, meaning that farmers participating in irrigation farming are more economically efficient in their rice production than those in rain fed production. Irrigation ecology has positive impact on production efficiency; hence farmers should be encouraged to produce more under irrigation for increased yield and profit.

scholarly journals Biomarkers responses in fish (Atherinella brasiliensis) of paranaguá bay, southern Brazil, for assessment of pollutant effects

2013 ◽  
Vol 61 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Ciro Alberto de Oliveira Ribeiro ◽  
Alberto Katsumiti ◽  
Patrícia França ◽  
Jocieli Maschio ◽  
Eliandra Zandoná ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Protected Areas ◽  
Aquatic Organisms ◽  
Southern Brazil ◽  
Paranaguá Bay ◽  
Fuel Oils ◽  
Polycyclic Aromatic ◽  
Biochemical Genetic ◽  
Autumn And Winter ◽  
The Impact

Paranaguá bay is a complex estuary located in southern Brazil containing three protected areas listed by UNESCO. Historically, the estuary has been affected by urban, industrial, agricultural and harbor activities, and occasional accidents. Specifically, the explosion of the Chilean ship Vicuña in December 2004 spilled methanol and crude and fuel oils which affected both protected and non-protected areas. The present study sought to investigate the pollution threat to aquatic organisms in order to evaluate the potential effects of pollutants. One hundred and twenty adult fish Atherinella brasiliensis were collected from different sites within Paranaguá estuary, including the harbor and open ocean, during summer, autumn and winter of 2005. Among the biomarkers, the somatic index, chemical analysis of bile, biochemical, genetic and morphological parameters were considered. Chemical analysis of bile showed a continuous bioavailability of polycyclic aromatic hydrocarbons (PAHs) according to proximity to the harbor site. The histopathological findings have demonstrated aconsiderable incidence of severe pathologies in the liver and gills, corroborated by biochemical disturbances and genetic damage. These findings indicate that more studies are necessary to evaluate both water quality and fish health so as to permit a better analysis of the impact of pollution in Paranaguá estuary.

scholarly journals The impact of governance on the outcomes of contracting out

2017 ◽  
Vol 3 (4) ◽  
pp. 215-233
Author(s):  
Jacob Torfing ◽  
Eva Sørensen ◽  
Lena Brogaard
Keyword(s):  
Systematic Review ◽  
Economic Efficiency ◽  
Local Governance ◽  
Impact Factors ◽  
International Studies ◽  
Value For Money ◽  
Public Authorities ◽  
Contracting Out ◽  
Private Actors ◽  
The Impact

Whether contracting out to private actors results in value for money depends on how public authorities govern, organize and manage service contracting. However, only a few studies have attempted to investigate how local governing practices can help to ensure that the contracting out of public services enhances economic efficiency and service quality. To further advance our knowledge on this topic, we present the results of a systematic review of 21 international studies, published between 2000 and 2018, on the impact of governance on the outcomes of contracting out. We combine insights from the reviewed studies to develop a theoretical framework of use to both practitioners and researchers that posits how eight impact factors mediate the influence of local governance on the outcomes of contracting out.

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