China 
Africa 
Explore chapters and articles related to this topic
Biotechnology in the Refinery
Published in Wael Ahmed Ismail, Jonathan Van Hamme, Hydrocarbon Biotechnology, 2023
Nour Sh. El-Gendy, James G. Speight
Sulfur-which is the third most abundant element in crude oil after carbon and hydrogen-is a major concern for refiners and is used as a determinant of the value of crude oils. Heavy crude oil and bitumen contain 3 to 6% sulfur, and sulfur must be removed before oils are used as a refinery feedstock. The combustion of sulfur-containing fuels leads to the increased emissions of sulfur oxides (SOx) which are major contributors to acid rain and also particulate matter. It has been reported that the total particulate matter emissions from diesel-fueled vehicles are proportional to the diesel sulfur content (Stanislaus et al., 2010; Mohebali and Ball, 2016). If desulfurization occurs on the crude feedstocks before they enter the refinery system, this would minimize the downstream desulfurization costs through reduced catalyst poisoning and reduced hydrogen usage (El-Gendy and Nassar, 2018). Viscous, high-density crude oils normally contain higher amounts of more complex sulfur compounds, with aliphatic acyclic sulfides (thioethers) and cyclic sulfides (thiolanes) being most amenable to hydrodesulfurization (HDS) and thermal treatments. Aromatic sulfur compounds, such as thiophenes and the benzo-derivatives (e.g., benzothiophenes, dibenzothiophenes (DBTs), and benzonaphthothiophenes) are considerably recalcitrant for HDS and thermal conversion (Gray et al. 1996; El-Gendy and Nassar, 2018; Nassar et al. 2021 c).
Introduction to Biofuels
Published in K.A. Subramanian, Biofueled Reciprocating Internal Combustion Engines, 2017
Fossil fuel reserves deplete at a faster rate due to large consumption, resulting in a huge gap in demand and supply. Diesel and gasoline fuels, which are derived from the feedstock of petroleum crude oil, are used as the main fuels in internal combustion engines. An internal combustion engine fueled with petroleum fuels during combustion emits harmful emissions such as carbon monoxide (CO), hydrocarbon (HC), NOx, and smoke/particulate matter. Biofuels are a viable option to tackle these issues. Fossil fuels that are generally embedded with sulfur result in the formation of SOx emissions during combustion. Sulfur molecules are generally not embedded with biofuels, which are structured with elements such as carbon, hydrogen, nitrogen, and oxygen. The composition of biofuels does not generally have aromatic content. The molecular structure of biofuels does not embed with sulfur (CxHyOz) and aromatics but it contains oxygen, which helps to better oxidation of hydrocarbon during combustion.
Clean combustion and emission control
Published in Emily S. Nelson, Dhanireddy R. Reddy, Green Aviation: Reduction of Environmental Impact Through Aircraft Technology and Alternative Fuels, 2018
H2O and CO2 are greenhouse gases; that is, they impact climate change. Their emissions are directly related to the amount of fuel burned. Fuel consumption is largely self-controlled by the aviation industry, which is operating under the tight constraints imposed by economic pressures. Figure 6.1 shows equilibrium values of these emissions at one inlet temperature and four pressures. SOx impacts local air quality; consequently, they have been regulated by the U.S. Environmental Protection Agency (EPA). However, SOx are not a regulated aircraft engine emission. Instead, they are controlled through limitations on jet fuel sulfur content.
A comprehensive review of four decades of thermally efficient biomass cookstove initiatives for sustainable development in India
Published in International Journal of Ambient Energy, 2022
R. K. Aggarwal, Shyam Singh Chandel
Biomass burning also emits NOx. High N-content in the fuel and high combustion temperatures increases NOx emissions in biomass-burning cookstove (Obernberger and Brunner 2005). Oxides of nitrogen (NOx), nitric oxide (NO) and nitrogen dioxide (NO2) are formed by the oxidation of nitrogen, both in the fuel and in the air. The concentration of nitrous oxide is low but contributes to global warming. Emissions of NOx range between 303 mg/m3 (95 g/GJ) for wet wood and 674 mg/m3 (211 g/GJ) for dry wood. The uncontrolled higher burning wood can yield higher flame temperatures forms higher NOx. NOx can be reduced by reducing flame temperature, providing secondary air to main combustion chamber and flue gas recirculation without compromising on combustion efficiency. Wood contains low Sulphur content with emissions of Sulphur oxides (primarily Sulphur dioxide) estimated at 10.8 g/GJ by the USEPA. SOx can be reduced with flue gas scrubbing, but it will be costly (Beauchemin and Tampier 2008).
An overview of viscosity reduction techniques on hydrocarbon fluids
Published in International Journal of Ambient Energy, 2022
Rakesh Kumar Sidheshware, S. Ganesan, Virendra Bhojwani
Under different operating conditions and Fuel/Air ratio, emission of CO, HC, oxides of Nitrogen and Sulphur are mainly due incomplete chemical reaction in combustion chamber. Pollutants like aerosols, Aldehydes and Soot particles are the products of Diesel engine combustion which exhausted to atmosphere can penetrate deeply into human lungs. Sulphur oxides (SOx) in the exhaust emission, promotes acid rain. Higher combustion temperature approximately 11000C results emission of nitrogen oxides (NOx), demonstrated to be hazardous to both plant and animal health. Vijaya Kumar, Patro, and Pudi (2014) installed magnets on fuel line to ionise inorder to have complete combustion reaction emitting less harmful emission and data recorded 5% less emission than conventional methods.