Recognition and Prevention of Distillate Fuel Emulsions

2006 ◽  
Author(s):  
T. D. Newbound ◽  
A. N. Al-Nasser ◽  
M. P. Sang ◽  
W. J. Carrigan
Keyword(s):  
Gas Turbine ◽  
Microbial Activity ◽  
Red Sea ◽  
Diesel Fuel ◽  
Sodium Sulfate ◽  
Sea Water ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Water Soluble ◽  
High Concentrations

This paper describes a case study involving chronic plugging of 5μm particulate filters in a gas turbine diesel fuel system in a Red Sea refinery. Rapid plugging of the filters was caused by water-in-diesel emulsions generated in diesel fuel supply tanks. Sludge with a wax-like appearance recovered from the 5 μm filters was, in fact, found to be composed of up to 50 percent water with no significant wax content. X-ray studies of the filter catch solids revealed a variety of iron oxide phases, sodium chloride, and high concentrations of sodium sulfate. Microbial cultures inoculated from storage tank ‘rag’ layers yielded moderate to high counts of general aerobic bacteria (GAB), moderate fungal cultures (yeast and molds) and low sulfate reducing bacteria (SRB). Elemental analysis of water in supply tanks where microbial activity was highest revealed ion concentrations similar to those found in Red Sea water. Sulfur isotope ratios in sulfate from filter catches suggest that much of the sulfate was derived from microbial metathesis of sulfur-bearing hydrocarbons. Frequent contamination of on-shore liquid hydrocarbon fuel tanks with sea water can cause corrosion and create a favorable environment for bacterial growth. Surfactant byproducts of microbial activity are capable of stabilizing emulsions, suspending water soluble salts such as sodium sulfate, and metals such as lead and copper. Copper is well known to promote gum formation, while all of these contaminants are potentially corrosive to gas turbine hot gas path components.

COASTAL AND ESTUARINE SEDIMENT DYNAMICS IN THE MEZEN BAY AND ESTUARIES MEZEN AND KULOY

2018 ◽  
Author(s):  
Н. Демиденко ◽  
N. Demidenko
Keyword(s):  
River Water ◽  
River Discharge ◽  
Sea Water ◽  
Sediment Dynamics ◽  
Estuarine Sediment ◽  
Sea Surface ◽  
Cross Sectional ◽  
Sand Waves ◽  
Tidal Estuaries ◽  
High Concentrations

In the Mezen bay and estuaries Mezen and Kuloy can be high concentrations of mud suspension there, involving the formation at times mobile suspensions and settled mud. Within estuaries the river water is mixed with the sea water by the action of tidal motions, by waves on the sea surface and by the river discharge forcing its way to the sea. Nearly all shallow tidal estuaries, where currents exceed about 1,0m s-1 and where sand is present, have sand waves. Sand waves have a variety of cross-sectional and plan forms.

scholarly journals Role of Inorganic and Organic Fractions in Animal Manure Compost in Lead Immobilization and Microbial Activity in Soil

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Masahiko Katoh ◽  
Wataru Kitahara ◽  
Takeshi Sato
Keyword(s):  
Microbial Activity ◽  
Contaminated Soil ◽  
Animal Manure ◽  
Water Soluble ◽  
Residual Fraction ◽  
Inorganic Component ◽  
Manure Compost ◽  
Microbial Enzyme ◽  
Lead Immobilization ◽  
Inorganic Fraction

This study aimed to identify how the ratio of inorganic-to-organic components in animal manure compost (AMC) affected both lead immobilization and microbial activity in lead-contaminated soil. When AMC containing 50% or more inorganic fraction with high phosphorous content was applied to contaminated soil, the amounts of water-soluble lead in it were suppressed by over 88% from the values in the soil without compost. The residual fraction under sequential extraction increased with the inorganic fraction in the AMC; however, in those AMCs, the levels of microbial enzyme activity were the same or less than those in the control soil. The application of AMC containing 25% inorganic fraction could alter the lead phases to be more insoluble while improving microbial enzyme activities; however, no suppression of the level of water-soluble lead existed during the first 30 days. These results indicate that compost containing an inorganic component of 50% or more with high phosphorus content is suitable for immobilizing lead; however, in the case where low precipitation is expected for a month, AMC containing 25% inorganic component could be used to both immobilize lead and restore microbial activity.

scholarly journals NMR Structure and Action on Nicotinic Acetylcholine Receptors of Water-soluble Domain of Human LYNX1

2011 ◽  
Vol 286 (12) ◽  
pp. 10618-10627 ◽  
Author(s):  
Ekaterina N. Lyukmanova ◽  
Zakhar O. Shenkarev ◽  
Mikhail A. Shulepko ◽  
Konstantin S. Mineev ◽  
Dieter D'Hoedt ◽  
...  
Keyword(s):  
Nicotinic Acetylcholine Receptors ◽  
Acetylcholine Receptors ◽  
Nmr Structure ◽  
Water Soluble ◽  
Gpi Anchor ◽  
Nicotinic Acetylcholine ◽  
Brain Functions ◽  
The Central Nervous System ◽  
High Concentrations

Discovery of proteins expressed in the central nervous system sharing the three-finger structure with snake α-neurotoxins provoked much interest to their role in brain functions. Prototoxin LYNX1, having homology both to Ly6 proteins and three-finger neurotoxins, is the first identified member of this family membrane-tethered by a GPI anchor, which considerably complicates in vitro studies. We report for the first time the NMR spatial structure for the water-soluble domain of human LYNX1 lacking a GPI anchor (ws-LYNX1) and its concentration-dependent activity on nicotinic acetylcholine receptors (nAChRs). At 5–30 μm, ws-LYNX1 competed with 125I-α-bungarotoxin for binding to the acetylcholine-binding proteins (AChBPs) and to Torpedo nAChR. Exposure of Xenopus oocytes expressing α7 nAChRs to 1 μm ws-LYNX1 enhanced the response to acetylcholine, but no effect was detected on α4β2 and α3β2 nAChRs. Increasing ws-LYNX1 concentration to 10 μm caused a modest inhibition of these three nAChR subtypes. A common feature for ws-LYNX1 and LYNX1 is a decrease of nAChR sensitivity to high concentrations of acetylcholine. NMR and functional analysis both demonstrate that ws-LYNX1 is an appropriate model to shed light on the mechanism of LYNX1 action. Computer modeling, based on ws-LYNX1 NMR structure and AChBP x-ray structure, revealed a possible mode of ws-LYNX1 binding.

Stabilization of liquid hydrocarbon fuel combustion by using a programmable microwave discharge in a subsonic airflow

2012 ◽  
Vol 38 (6) ◽  
pp. 503-512 ◽  
Author(s):  
P. V. Kopyl ◽  
O. S. Surkont ◽  
V. M. Shibkov ◽  
L. V. Shibkova
Keyword(s):  
Microwave Discharge ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Fuel Combustion

OPTIMIZATION OF GAS-DIESEL ENGINE REGULATION AS A METHOD OF IMPROVING ITS ECOLOGICAL CHARACTERISTICS

2021 ◽  
pp. 28-32
Author(s):  
VALERIY L. CHUMAKOV ◽  
Keyword(s):  
Carbon Monoxide ◽  
Diesel Engine ◽  
Nitrogen Oxides ◽  
Diesel Fuel ◽  
Hydrocarbon Fuel ◽  
Load Range ◽  
Engine Operation ◽  
Exhaust Gases ◽  
Wide Range ◽  
Diesel Cycle

The paper shows some ways to improve the environmental characteristics of a diesel engine using gaseous hydrocarbon fuel and operating the engine in a gas-diesel cycle mode. Some possibilities to reduce toxic components of exhaust gases in a gas-diesel engine operating on liquefi ed propane-butane mixtures have been studied. Experiments carried out in a wide range of load from 10 to 100% and speed from 1400 to 2000 rpm showed that the gas-diesel engine provides a suffi ciently high level of diesel fuel replacement with gas hydrocarbon fuel. The authors indicate some eff ective ways to reduce the toxicity of exhaust gases. The engine power should be adjusted by the simultaneous supply of fuel, gas and throttling the air charge in the intake manifold. This method enriches the fi rst combusting portions to reduce nitrogen oxides and maintains the depletion of the main charge within the fl ammability limits of the gas-air charge to reduce carbon monoxide and hydrocarbons. The authors found that when the engine operates in a gas-diesel cycle mode, the power change provides a decrease in nitrogen oxide emissions of gas-diesel fuel only due to gas supply in almost the entire load range as compared to the pure diesel. At high loads (more than 80%) stable engine operation is ensured up to 90% of diesel fuel replaced by gas. Even at 10% of diesel fuel used the concentration of nitrogen oxides decreases by at least 15…20% as compared with a diesel engine in the entire load range. However, there is an increased emission of hydrocarbons and carbon monoxide in the exhaust gases. Further experimental studies have shown that optimization of the gas diesel regulation can reduce the mass emission of nitrogen oxides contained in exhaust gases in 2…3 times and greatly reduce the emission of incomplete combustion products – carbon monoxide and hydrocarbons.

scholarly journals Characteristics of aerosol pollution during heavy haze events in Suzhou, China

2016 ◽  
Vol 16 (11) ◽  
pp. 7357-7371 ◽  
Author(s):  
Mi Tian ◽  
Huanbo Wang ◽  
Yang Chen ◽  
Fumo Yang ◽  
Xiaohua Zhang ◽  
...  
Keyword(s):  
Gas Phase ◽  
Inorganic Ions ◽  
Weather Conditions ◽  
Water Soluble ◽  
Chemical Components ◽  
Formation Mechanisms ◽  
Visibility Impairment ◽  
Aerosol Pollution ◽  
Haze Formation ◽  
High Concentrations

Abstract. Extremely severe haze weather events occurred in many cities in China, especially in the east part of the country, in January 2013. Comprehensive measurements including hourly concentrations of PM2.5 and its major chemical components (water-soluble inorganic ions, organic carbon (OC), and elemental carbon (EC)) and related gas-phase precursors were conducted via an online monitoring system in Suzhou, a medium-sized city in Jiangsu province, just east of Shanghai. PM2.5 (particulate matter with an aerodynamic diameter of 2.5 µm or less) frequently exceeded 150 µg m−3 on hazy days, with the maximum reaching 324 µg m−3 on 14 January 2013. Unfavorable weather conditions (high relative humidity (RH), and low rainfall, wind speed, and atmospheric pressure) were conducive to haze formation. High concentrations of secondary aerosol species (including SO42−, NO3−, NH4+, and SOC) and gaseous precursors were observed during the first two haze events, while elevated primary carbonaceous species emissions were found during the third haze period, pointing to different haze formation mechanisms. Organic matter (OM), (NH4)2SO4, and NH4NO3 were found to be the major contributors to visibility impairment. High concentrations of sulfate and nitrate might be explained by homogeneous gas-phase reactions under low RH conditions and by heterogeneous processes under relatively high RH conditions. Analysis of air mass trajectory clustering and potential source contribution function showed that aerosol pollution in the studied areas was mainly caused by local activities and surrounding sources transported from nearby cities.

Effect of Long-Lived Species Generated by Non-Thermal Plasmas on the Auto-Ignition Delay of Liquid Hydrocarbon Fuel-Air Pre-Mixtures

2017 ◽  
Vol 189 (9) ◽  
pp. 1624-1638 ◽  
Author(s):  
Takuma Ono ◽  
Takehiko Segawa ◽  
Naoaki Saito ◽  
Eiichi Takahashi ◽  
Makihito Nishioka
Keyword(s):  
Ignition Delay ◽  
Hydrocarbon Fuel ◽  
Liquid Hydrocarbon ◽  
Thermal Plasmas ◽  
Auto Ignition

scholarly journals High concentrations of coarse particles emitted from a cattle feeding operation

2011 ◽  
Vol 11 (16) ◽  
pp. 8809-8823 ◽  
Author(s):  
N. Hiranuma ◽  
S. D. Brooks ◽  
J. Gramann ◽  
B. W. Auvermann
Keyword(s):  
United States ◽  
Particulate Matter ◽  
Chemical Properties ◽  
Field Measurements ◽  
The United States ◽  
Water Soluble ◽  
Size Distributions ◽  
Cattle Feeding ◽  
High Concentrations ◽  
Organic Particles

Abstract. Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United States. In the summer of 2008, measurements and samplings were conducted at the upwind and downwind edges of the facility. A series of far-field measurements and samplings was also conducted 3.5 km north of the facility. Two instruments, a GRIMM Sequential Mobility Particle Sizer (SMPS) and a GRIMM Portable Aerosol Spectrometer (PAS), were used to measure particle size distributions over the range of 0.01 to 25 μm diameter. Raman microspectroscopy was used to determine the chemical composition of particles on a single particle basis. Volume size distributions of dust were dominated by coarse mode particles. Twenty-four hour averaged concentrations of PM10 (particulate matter with a diameter of 10 μm or less) were as high as 1200 μg m−3 during the campaign. The primary constituents of the particulate matter were carbonaceous materials, such as humic acid, water soluble organics, and less soluble fatty acids, including stearic acid and tristearin. A significant fraction of the organic particles was present in internal mixtures with salts. Basic characteristics such as size distribution and composition of agricultural aerosols were found to be different than the properties of those found in urban and semi-urban aerosols. Failing to account for such differences may lead to errors in estimates of aerosol effects on local air quality, visibility, and public health.

scholarly journals Characteristics, seasonality and sources of carbonaceous and ionic components in the tropical Indian aerosols

2011 ◽  
Vol 11 (2) ◽  
pp. 3937-3976 ◽  
Author(s):  
C. M. Pavuluri ◽  
K. Kawamura ◽  
S. G. Aggarwal ◽  
T. Swaminathan
Keyword(s):  
Organic Carbon ◽  
Atmospheric Aerosols ◽  
Atmospheric Transport ◽  
Indian Subcontinent ◽  
Ionic Species ◽  
Water Soluble ◽  
Carbonaceous Aerosols ◽  
Mass Fractions ◽  
High Concentrations ◽  
Ionic Components

Abstract. To better characterize South and Southeast Asian aerosols, PM10 samples collected from tropical Chennai, India (13.04° N; 80.17° E) were analyzed for carbonaceous and water-soluble ionic components. Concentration ranges of elemental carbon (EC) and organic carbon (OC) were 2.4–14 μg m−3 and 3.2–15.6 μg m−3 in winter samples whereas they were 1.1–2.5 μg m−3 and 4.1–17.6 μg m−3 in summer samples, respectively. Concentration of secondary organic carbon (SOC) retrieved from EC-tracer method was 4.6 ± 2.8 μg m−3 in winter and 4.3 ± 2.8 μg m−3 in summer. SO42- (8.8 ± 2.5 μg m−3 and 4.1 ± 2.7 μg m−3 in winter and summer, respectively) was found as the most abundant ionic species (57% on average, n = 49), followed by NH4+ (15%) > NO3− > Cl− > K+> Na+ > Ca2+ > MSA− > Mg2+. The mass fractions of EC, organic matter (OM) and ionic species varied seasonally, following the air mass trajectories and corresponding source strength. Based on mass concentration ratios of selected components and relations of EC and OC to marker species, we found that biofuel/biomass burning is the major source of atmospheric aerosols in South and Southeast Asia. The high concentrations of SOC and WSOC/OC ratios (ave. 0.45; n = 49) as well as good correlations between SOC and WSOC suggest that the secondary production of organic aerosols during long-range atmospheric transport is also significant in this region. This study provides the baseline data of carbonaceous aerosols for southern part of the Indian subcontinent.

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