Characterization and Combustion of SRC II Fuel Oil

1980 ◽  
Vol 102 (3) ◽  
pp. 672-678
Author(s):  
W. Downs ◽  
S. J. Vecci ◽  
J. A. Barsin ◽  
W. C. Rovesti
Keyword(s):  
Experimental Evaluation ◽  
Fuel Oil ◽  
Petroleum Distillate ◽  
Nox Emissions ◽  
Combustion Control ◽  
Control Techniques ◽  
Combustion Properties ◽  
High Concentrations ◽  
The One ◽  
Combustion Tests

This paper deals with an experimental evaluation of the combustion properties of solvent refined coal II fuel oil. The purpose was to identify problems, if any, associated with handling, storing, pumping, and burning SRC fuel oil. Detailed fuels characterizations were performed and compared to petroleum distillate products. Laboratory fuel analyses and combustion tests were performed with SRC fuel oil, No. 2 fuel oil, and No. 5 fuel oil. Four B&W atomizers were tested and two B&W oil burners were utilized. The laboratory fuel analyses indicated that in most respects this SRC fuel oil sample behaved similarly to No. 2 fuel oil. The combustion tests confirmed that expectation. The one identified problem was relatively high concentrations of fuel-bound nitrogen and, consequently NOx emissions were relatively high. It was concluded that SRC fuel oil may require the application of NOx combustion control techniques.

scholarly journals Conversion of Liquid to Gaseous Fuel for Prevaporised Premixed Combustion in Gas Turbines

1997 ◽  
Author(s):  
Y. Wang ◽  
L. Reh ◽  
D. Pennell ◽  
D. Winkler ◽  
K. Döbbeling
Keyword(s):  
High Pressure ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Liquid Fuel ◽  
Fuel Injection ◽  
Premixed Combustion ◽  
Fuel Oil ◽  
Injection System ◽  
Nox Emissions ◽  
Combustion Tests

Stationary gas turbines for power generation are increasingly being equipped with low emission burners. By applying lean premixed combustion techniques for gaseous fuels both NOx and CO emissions can be reduced to extremely low levels (NOx emissions <25vppm, CO emissions <10vppm). Likewise, if analogous premix techniques can be applied to liquid fuels (diesel oil, Oil No.2, etc.) in gas-fired burners, similar low level emissions when burning oils are possible. For gas turbines which operate with liquid fuel or in dual fuel operation, VPL (Vaporised Premixed Lean)-combustion is essential for obtaining minimal NOx-emissions. An option is to vaporise the liquid fuel in a separate fuel vaporiser and subsequently supply the fuel vapour to the natural gas fuel injection system; this has not been investigated for gas turbine combustion in the past. This paper presents experimental results of atmospheric and high-pressure combustion tests using research premix burners running on vaporised liquid fuel. The following processes were investigated: • evaporation and partial decomposition of the liquid fuel (Oil No.2); • utilisation of low pressure exhaust gases to externally heat the high pressure fuel vaporiser; • operation of ABB premix-burners (EV burners) with vaporised Oil No.2; • combustion characteristics at pressures up to 25bar. Atmospheric VPL-combustion tests using Oil No.2 in ABB EV-burners under simulated gas turbine conditions have successfully produced emissions of NOx below 20vppm and of CO below 10vppm (corrected to 15% O2). 5vppm of these NOx values result from fuel bound nitrogen. Little dependence of these emissions on combustion pressure bas been observed. The techniques employed also ensured combustion with a stable non luminous (blue) flame during transition from gaseous to vaporised fuel. Additionally, no soot accumulation was detectable during combustion.

Semi–Empirical Predictions and Correlations of NOx Emissions From Utility Combustion Turbines

1995 ◽  
Author(s):  
Donald M. Newburry ◽  
Arthur M. Mellor
Keyword(s):  
Natural Gas ◽  
A Priori ◽  
Fuel Oil ◽  
Pollutant Emissions ◽  
Nox Emissions ◽  
Time Model ◽  
Heterogeneous Effects ◽  
Inlet Conditions ◽  
Thermal Nox ◽  
Semi Empirical

Semi–empirical equations model the dominant subprocesses involved in pollutant emissions by assigning specific times to the fuel evaporation, chemistry, and turbulent mixing. They then employ linear ratios of these times with model constants established by correlating data from combustors with different geometries, inlet conditions, fuels, and fuel injectors to make a priori predictions. In this work, thermal NOx emissions from two heavy–duty, dual fuel (natural gas and fuel oil #2) diffusion flame combustors designated A and B operating without inert injection are first predicted, and then correlated using three existing semi–empirical approaches termed the Lefebvre (AHL) model, the Rizk–Mongia (RM) model, and the characteristic time model (CTM). Heterogeneous effects were found to be significant, as fuel droplet evaporation times were required to align the natural gas and fuel oil data. Only the RM model and CTM were employed to study this phenomenon. The CTM achieved the best overall prediction and correlation, as the data from both combustors fell within one standard deviation of the predicted line. The AHL and RM models were not able to account for the geometries of the two combustors. For Combustor A the CTM parameter correlated the data in a highly linear manner, as expected, but for Combustor B there was significant curvature. Using the CTM this was shown to be a residence time effect.

Combustion Optimization for the ALSTOM GT13E2 Gas Turbine

2006 ◽  
Author(s):  
Ch. Steinbach ◽  
N. Ulibarri ◽  
M. Garay ◽  
H. Lu¨bcke ◽  
Th. Meeuwissen ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Flame Temperature ◽  
Air Entrainment ◽  
Flame Stabilization ◽  
Flame Stability ◽  
Nox Emissions ◽  
Combustion Control ◽  
Control Logic ◽  
The Individual ◽  
Combustion Optimization

The NOx emissions of low NOx premix combustors are not only determined by the burner design, but also by the multi burner interaction and the related distribution of air and fuel flows to the individual burners. Often the factors that have a positive impact on NOx emission have a negative impact on the flame stability, so the main challenge is to find an optimum point with the lowest achievable NOx while maintaining good flame stability. The hottest flame zones are where most of the NOx is formed. Avoiding such zones in the combustor (by homogenization of the flame temperature) reduces NOx emissions significantly. Improving the flame stability and the combustion control allows the combustor to operate at a lower average flame temperature and NOx emissions. ALSTOM developed a combustion optimization package for the GT13E2. The optimization package development focused on three major issues: • Flame stability; • Homogenization of flame temperature distribution in the combustor; • Combustion control logic. The solution introduced consists of: • The reduction of cooling air entrainment in the primary flame zone for improved flame stability; • The optical measurement of the individual burner flame temperatures and their homogenization by burner tuning valves; • Closed loop control logic to control the combustion dependent on the pulsation signal. This paper shows how fundamental combustion research methods were applied to derive effective optimization measures. The flame temperature measurement technique will be presented along with results of the measurement and their application in homogenization of the combustor temperature distribution in an engine equipped with measures to improve flame stabilization. The main results achieved are: • Widening of the main burner group operation range; • Improved use of the low NOx operation range; • NOx reduction at the combustor pulsation limit and hence, large margins to the European emission limit (50 mg/m3 @ 15%O2).

PROPERTIES OF BOILER FUEL COMPOUNDED BY NARROW FUEL FRACTIONS

2021 ◽  
pp. 22-29
Author(s):  
K. Shevchenko ◽  
A. Grigorov ◽  
I. Sinkevich
Keyword(s):  
Raw Materials ◽  
Fire Hazard ◽  
Flash Point ◽  
Fuel Oil ◽  
Raw Material ◽  
Material Base ◽  
Boiler Fuel ◽  
Performance Properties ◽  
Lower Heat ◽  
The One

In order to improve the performance properties, in particular viscosity-temperature, of boiler fuel, it is proposed to combine them with narrow fuel fractions obtained by thermal destruction of secondary polymer raw materials (low pressure polyethylene and polypropylene). When compounding grade 100 fuel oil with narrow fuel fractions, the values ​​of density are reduced to 865 (873) kg / m3, conditional viscosity to 2.50 (2.63) deg. um., pour point up to 8 (13) °C), sulfur content up to 0.17 wt%. and the lower heat of combustion increases to 43606 (43850) kJ / kg. At the same time, there is a gradual decrease in the value of the flash point to 114 (127) °C. This reduction is a negative point, which leads to increased fire safety of fuel oil during its use, storage, pumping and transport. However, the values of the flash point, according to the requirements of regulatory documentation, are within acceptable limits. That is, the value of this indicator can limit the content of fuel oil in narrow fuel fractions. It is determined that the rational concentration of narrow fuel fractions in the composition of fuel oil grade 100, is within 30% of the mass. Within these limits, there is a permissible decrease in flash point values – an indicator that characterizes the fire hazard of fuel oil during its use, storage, pumping and transportation against the background of improving other performance properties of fuel oil. The production of the proposed compound boiler fuel on the one hand allows to expand the raw material base of the process by involving in the production process secondary polymer raw materials – solid waste subject to mandatory disposal, on the other – to meet existing demand for boiler fuel by increasing its production.

Taurine secretion in primary monolayer cultures of flounder renal epithelium: stimulation by low osmolality

2000 ◽  
Vol 279 (2) ◽  
pp. R704-R712 ◽  
Author(s):  
Siribhinya Benyajati ◽  
J. Larry Renfro
Keyword(s):  
Transport Systems ◽  
Disulfonic Acid ◽  
Renal Epithelium ◽  
Ussing Chambers ◽  
Monolayer Cultures ◽  
High Concentrations ◽  
The One ◽  
Secretory System ◽  
Taurine Efflux

Transepithelial taurine fluxes determined in short-circuited monolayer cultures of flounder renal proximal cells in Ussing chambers revealed net taurine secretion. Both unidirectional secretory and reabsorptive taurine fluxes exhibited saturation kinetics contributed by two distinct saturable transepithelial taurine transport systems operating at different taurine concentration ranges. The taurine secretory system operating below 0.5 mM had lower affinity but higher capacity than the reabsorptive system, whereas the one operating at high concentrations (0.5–3.0 mM) had higher affinity but the same capacity as the corresponding reabsorptive system. Exposure (2 h) of the cultures to hyposmotic medium in the presence of taurine increased taurine secretory flux twofold with no effect on the reabsorptive flux. The hyposmolality-induced increase in taurine secretion was associated with a decreased peritubular taurine efflux and a concurrent increased luminal taurine efflux; the latter occurred via a pathway that was not affected by 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid but inhibited by probenecid. The culture response in hyposmotic medium mimics the in vivo response of the intact marine fish kidney to dilution.

scholarly journals VEGF-A in Cardiomyocytes and Heart Diseases

2020 ◽  
Vol 21 (15) ◽  
pp. 5294
Author(s):  
Mariantonia Braile ◽  
Simone Marcella ◽  
Leonardo Cristinziano ◽  
Maria Rosaria Galdiero ◽  
Luca Modestino ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Heart Diseases ◽  
Premature Death ◽  
Vascular Endothelial ◽  
Main Cell Type ◽  
High Concentrations ◽  
Cytokine Stimulation ◽  
The One ◽  
Endothelial Growth Factor

The vascular endothelial growth factor (VEGF), a homodimeric vasoactive glycoprotein, is the key mediator of angiogenesis. Angiogenesis, the formation of new blood vessels, is responsible for a wide variety of physio/pathological processes, including cardiovascular diseases (CVD). Cardiomyocytes (CM), the main cell type present in the heart, are the source and target of VEGF-A and express its receptors, VEGFR1 and VEGFR2, on their cell surface. The relationship between VEGF-A and the heart is double-sided. On the one hand, VEGF-A activates CM, inducing morphogenesis, contractility and wound healing. On the other hand, VEGF-A is produced by CM during inflammation, mechanical stress and cytokine stimulation. Moreover, high concentrations of VEGF-A have been found in patients affected by different CVD, and are often correlated with an unfavorable prognosis and disease severity. In this review, we summarized the current knowledge about the expression and effects of VEGF-A on CM and the role of VEGF-A in CVD, which are the most important cause of disability and premature death worldwide. Based on clinical studies on angiogenesis therapy conducted to date, it is possible to think that the control of angiogenesis and VEGF-A can lead to better quality and span of life of patients with heart disease.

ACETYLASPARTIC ACID AND AMMONIA POISONING

1960 ◽  
Vol 38 (7) ◽  
pp. 763-768 ◽  
Author(s):  
Jean-Paul Du Ruisseau
Keyword(s):  
Amino Acid ◽  
Ammonium Acetate ◽  
Normal Liver ◽  
The Other ◽  
Normal Brain ◽  
High Concentrations ◽  
The One ◽  
Ammonia Poisoning

Acetylaspartic acid has been followed in nine tissues of normal and ammonia-poisoned rats. This acetylated amino acid is present at high concentrations in normal brain and remains unchanged in ammonia-poisoned brain. Acetylaspartic acid is absent or present in trace amounts in normal liver. It increases appreciably in ammonium acetate poisoning, reaching a peak at death. No change in concentration was detectable in the other tissues examined. There is a correlation between aspartic and acetylaspartic acid in the liver. But no correlation was observed between acetylaspartic acid on the one hand and ammonia and urea on the other. The possible origins of acetylaspartic acid are discussed.

scholarly journals Crystallization of CaCO3 in Aqueous Solutions with Extremely High Concentrations of NaCl

Crystals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 647
Author(s):  
Mengqi Qian ◽  
Yuwei Zuo ◽  
Zhihao Chen ◽  
Xiaoshuang Yin ◽  
Ying Liu ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
High Concentration ◽  
Retention Efficiency ◽  
Static Test ◽  
Inductively Coupled ◽  
High Concentrations ◽  
The One ◽  
Phosphate Inhibitors

The effect of NaCl at extremely high concentrations from 3.5 to 14 wt. % on the crystallization of CaCO3 was investigated in depth. The static test experiment verified that the Ca2+ retention efficiency (η) of NaCl on CaCO3 scale increased from 31.06% (3.5 wt. %) to 41.56% (14 wt. %). Based on the calculation of supersaturation rations, the high concentration of NaCl could reduce the activity coefficients of [Ca2+] and [CO32−], thus reducing the actual concentration of CaCO3. The CaCO3 deposition rate constants (k) showed that NaCl slowed down the rate of CaCO3 crystallization. The X–ray diffraction (XRD) testing disclosed that the growth of (1 0 4) and (1 1 0) faces from calcite was impeded, while the formation of (1 1 1) face from aragonite was induced by the increasing concentration of NaCl. The inductively coupled plasma optical emission spectrometry (ICP–OES) results indicated that Na+ could be doped into CaCO3, leading to the one–dimensional crystal growth. It was further proved that NaCl heightens the efficiency of the typical phosphate inhibitors (2–phosphonobutane–1,2,4–tricarboxylic acid (PBTCA) and 1–hydroxyethane–1,1–diphosphonic acid (HEDP)) on prohibiting the scale of CaCO3.

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