Abstract: Methane is the second most important greenhouse gas
(GHG) after carbon dioxide. Amount of methane emission from
energy sector is increasing day by day with various activities. In
present work, various sources of methane emission from upstream,
middle stream and downstream of oil & gas sectors are identified and
categorised as per IPCC-2006 guidelines. Data were collected from
various oil & gas sector like (i) exploration & production of oil & gas
(ii) supply through pipelines (iii) refinery throughput & production
(iv) storage & transportation (v) usage. Methane emission factors for
various categories were determined applying Tier-II and Tier-I
approach using the collected data. Total methane emission from
Indian Oil & Gas sectors was thus estimated for the year 1990 to
2007.
Abstract: Observations and long-term trends indicate that climate
change impacts would be significant and affects Taiwan directly and
severely. Taiwan engages not only in mitigation, but also in adaptation.
However, there are cognitive gaps on adaptation between government
and populace. Besides, a vision of zero-carbon and renewable energy
100% will be adopted in future. Therefore, the objectives of this
article are to 1) hold a National Forum for knowing differences
between the strategies of zero-carbon and renewable energy 100% and
cognitions of general populace, and 2) plan a clear roadmap for the
vision, strategy, and measures. In this forum, we set 5 group topics, 5
presumed themes, and issues mentioned review for concluding the
critical issues. Finally, there are 4 strategies and 14 critical issues
which correlate with the vision and strategy of government and the
cognition of the general populace.
Abstract: MOC (method of cell) is a new method of investigating
wave propagating in material with periodic microstructure, and can
reflect the effect of microstructure. Wave propagation in periodically
laminated medium consisting of linearly elastic layers can be treated
as a special application of this method. In this paper, it was used to
simulate the dynamic response of carbon-phenolic to impulsive
loading under certain boundary conditions. From the comparison
between the results obtained from this method and the exact results
based on propagator matrix theory, excellent agreement is achieved.
Conclusion can be made that the oscillation periodicity is decided by
the thickness of sub-cells. In the end, the NHDMOC method, which
permits studying stress wave propagation with one dimensional strain,
was applied to study the one-dimensional stress wave propagation. In
this paper, the ZWT nonlinear visco-elastic constitutive relationship
with 7 parameters, NHDMOC, and corresponding equations were
deduced. The equations were verified, comparing the elastic stress
wave propagation in SHPB with, respectively, the elastic and the
visco-elastic bar. Finally the dispersion and attenuation of stress wave
in SHPB with visco-elastic bar was studied.
Abstract: The aim of this study was to synthesize the single
walled carbon nanotubes (SWCNTs) and determine their hydrogen
storage capacities. SWCNTs were firstly synthesized by chemical
vapor deposition (CVD) of acetylene (C2H2) on a magnesium oxide
(MgO) powder impregnated with an iron nitrate (Fe(NO3)3·9H2O)
solution. The synthesis parameters were selected as: the synthesis
temperature of 800°C, the iron content in the precursor of 5% and the
synthesis time of 30 min. Purification process of SWCNTs was
fulfilled by microwave digestion at three different temperatures (120,
150 and 200 °C), three different acid concentrations (0.5, 1 and 1.5
M) and for three different time intervals (15, 30 and 60 min). Nitric
acid (HNO3) was used in the removal of the metal catalysts. The
hydrogen storage capacities of the purified materials were measured
using volumetric method at the liquid nitrogen temperature and gas
pressure up to 100 bar. The effects of the purification conditions such
as temperature, time and acid concentration on hydrogen adsorption
were investigated.
Abstract: Composting is the process in which municipal solid
waste (MSW) and other organic waste materials such as biosolids
and manures are decomposed through the action of bacteria and other
microorganisms into a stable granular material which, applied to
land, as soil conditioner. Microorganisms, especially those that are
able to degrade polymeric organic material have a key role in speed
up this process. The aim of this study has been established to
isolation of microorganisms with high ability to production
extracellular enzymes for degradation of natural polymers that are
exists in MSW for decreasing time of degradation phase. Our
experimental study for isolation designed in two phases: in first
phase we isolated degrading microorganism with selected media that
consist a special natural polymer such as cellulose, starch, lipids and
etc as sole source of carbon. In second phase we selected
microorganism that had high degrading enzyme production with
enzymatic assay for seed production. However, our findings in pilot
scale have indicated that usage of this microbial consortium had high
efficiency for decreasing degradation phase.
Abstract: The main issue in sweetening natural gas is H2S
dissociation. The present study is concerned with simulating thermal
dissociation of H2S in industrial natural gas carbon black furnace.
The comparison of calculated results against experimental
measurements shows good agreement. The results show that sulfur
derived from H2S thermal dissociation peaked at φ=0.95. H2S
thermal dissociation is enhanced in equivalence ratio upper than 1
and H2S oxidization is increased in equivalence ratio lower than 1.
H2 concentration of H2S thermal dissociation is increased with
increase of equivalence ratio up to 1. Also, H2S concentration
decreased in outlet as equivalence ratio increases. H2S thermal
dissociation to hydrogen and Sulfur reduces its toxic characteristics
and make economical benefits.
Abstract: Paper presents knowledge about types of test in area
of materials properties of selected methods of rapid prototyping
technologies. In today used rapid prototyping technologies for
production of models and final parts are used materials in initial state
as solid, liquid or powder material structure. In solid state are used
various forms such as pellets, wire or laminates. Basic range
materials include paper, nylon, wax, resins, metals and ceramics. In
Fused Deposition Modeling (FDM) rapid prototyping technology are
mainly used as basic materials ABS (Acrylonitrile Butadiene
Styrene), polyamide, polycarbonate, polyethylene and polypropylene.
For advanced FDM applications are used special materials as silicon
nitrate, PZT (Piezoceramic Material - Lead Zirconate Titanate),
aluminium oxide, hydroxypatite and stainless steel.
Abstract: The modified Claus process is commonly used in oil
refining and gas processing to recover sulfur and destroy
contaminants formed in upstream processing. A Claus furnace feed
containing a relatively low concentration of H2S may be incapable of
producing a stable flame. Also, incomplete combustion of
hydrocarbons in the feed can lead to deterioration of the catalyst in
the reactors due to soot or carbon deposition. Therefore, special
consideration is necessary to achieve the appropriate overall sulfur
recovery. In this paper, some configurations available to treat lean
acid gas streams are described and the most appropriate ones are
studied to overcome low H2S concentration problems. As a result,
overall sulfur recovery is investigated for feed preheating and hot gas
configurations.
Abstract: In recent years, the underground water sources in
southern Taiwan have become salinized because of saltwater
intrusions. This study explores the adsorption characteristics of
activated carbon on salinizing inorganic salts using isothermal
adsorption experiments and provides a model analysis. The
temperature range for the isothermal adsorption experiments ranged
between 5 to 45 ℃, and the amount adsorbed varied between 28.21 to
33.87 mg/g. All experimental data of adsorption can be fitted to both
the Langmuir and the Freundlich models. The thermodynamic
parameters for per chlorate onto granular activated carbon were
calculated as -0.99 to -1.11 kcal/mol for DG°, -0.6 kcal/mol for DH°,
and 1.21 to 1.84 kcal/mol for DS°. This shows that the adsorption
process of granular activated carbon is spontaneously exothermic. The
observation of adsorption behaviors under low ionic strength, low pH
values, and low temperatures is beneficial to the adsorption removal of
perchlorate with granular activated carbon.
Abstract: In order to investigate a PROX microreactor
performance, two-dimensional modeling of the reacting flow
between two parallel plates is performed through a finite volume
method using an improved SIMPLE algorithm. A three-step surface
kinetics including hydrogen oxidation, carbon monoxide oxidation
and water-gas shift reaction is applied for a Pt-Fe/γ-Al2O3 catalyst
and operating temperatures of about 100ºC. Flow pattern, pressure
field, temperature distribution, and mole fractions of species are
found in the whole domain for all cases. Also, the required reactive
length for removing carbon monoxide from about 2% to less than 10
ppm is found. Furthermore, effects of hydraulic diameter, wall
temperature, and inlet mole fraction of air and water are investigated
by considering carbon monoxide selectivity and conversion. It is
found that air and water addition may improve the performance of
the microreactor in carbon monoxide removal in such operating
conditions; this is in agreement with the pervious published results.
Abstract: The machining of Carbon Fiber Reinforced Plastics
has come to constitute a significant challenge for many fields of
industry. The resulting surface finish of machined parts is of primary
concern for several reasons, including contact quality and impact on
the assembly. Therefore, the characterization and prediction of
roughness based on machining parameters are crucial for costeffective
operations. In this study, a PCD tool comprised of two
straight flutes was used to trim 32-ply carbon fiber laminates in a bid
to analyze the effects of the feed rate and the cutting speed on the
surface roughness. The results show that while the speed has but a
slight impact on the surface finish, the feed rate for its part affects it
strongly. A detailed study was also conducted on the effect of fiber
orientation on surface roughness, for quasi-isotropic laminates used
in aerospace. The resulting roughness profiles for the four-ply
orientation lay-up were compared, and it was found that fiber angle is
a critical parameter relating to surface roughness. One of the four
orientations studied led to very poor surface finishes, and
characteristic roughness profiles were identified and found to only
relate to the ply orientations of multilayer carbon fiber laminates.
Abstract: The aim of this work is to investigate on the internalflow
patterns in a plate heat exchanger channel, which affect the
rate of sedimentation fouling on the heat transfer surface of the
plate heat exchanger. The research methodologies were the
computer simulation using Computational Fluid Dynamics (CFD)
and the experimental works. COMSOL MULTIPHYSICS™
Version 3.3 was used to simulate the velocity flow fields to verify
the low and high flow regions. The results from the CFD technique
were then compared with the images obtained from the
experiments in which the fouling test rig was set up with a singlechannel
plate heat exchanger to monitor the fouling of calcium
carbonate. Two parameters were varied i.e., the crossing angle of
the two plate: 55/55, 10/10, and 55/10 degree, and the fluid flow
rate at the inlet: 0.0566, 0.1132 and 0.1698 m/s. The type of plate
“GX-12" (the surface area 0.12 m2, the depth 2.9 mm, the width of
fluid flow 215 mm and the thickness of stainless plate of 0.5 mm)
was used in this study. The results indicated that the velocity
distribution for the case of 55/55 degree seems to be very well
organized when compared with the others. Also, an increase in the
inlet velocity resulted in the reduction of fouling rate on the surface
of plate heat exchangers.
Abstract: The modified Claus process is the major technology
for the recovery of elemental sulfur from hydrogen sulfide. The
chemical reactions that can occur in the reaction furnace are
numerous and many byproducts such as carbon disulfide and carbon
carbonyl sulfide are produced. These compounds can often contribute
from 20 to 50% of the pollutants and therefore, should be hydrolyzed
in the catalytic converter. The inlet temperature of the first catalytic
reactor should be maintained over than 250 °C, to hydrolyze COS
and CS2. In this paper, the various configurations for the first
converter reheating of sulfur recovery unit are investigated. As a
result, the performance of each method is presented for a typical
clause unit. The results show that the hot gas method seems to be
better than the other methods.
Abstract: Carbon tetrachloride (CCl4) is a well-known
hepatotoxin and exposure to this chemical is known to induce
oxidative stress and causes liver injury by the formation of free
radicals. Flacourtia indica commonly known as 'Baichi' has been
reported as an effective remedy for the treatment of a variety of
diseases. The objective of this study was to investigate the
hepatoprotective activity of aqueous extract of leaves of Flacourtia
indica against CCl4 induced hepatotoxicity. Animals were pretreated
with the aqueous extract of Flacourtia indica (250 & 500 mg/kg
body weight) for one week and then challenged with CCl4 (1.5 ml/kg
bw) in olive oil (1:1, v/v) on 7th day. Serum marker enzymes (ALP,
AST, ALT, Total Protein & Total Bilirubin) and TBARS level
(Marker for oxidative stress) were estimated in all the study groups.
Alteration in the levels of biochemical markers of hepatic damage
like AST, ALT, ALP, Total Protein, Total Bilirubin and lipid
peroxides (TBARS) were tested in both CCl4 treated and extract
treated groups. CCl4 has enhanced the AST, ALT, ALP and the
Lipid peroxides (TBARS) in liver. Treatment of aqueous extract of
Flacourtia indica leaves (250 & 500 mg/kg) exhibited a significant
protective effect by altering the serum levels of AST, ALT, ALP,
Total Protein, Total Bilirubin and liver TBARS. These biochemical
observations were supported by histopathological study of liver
sections. From this preliminary study it has been concluded that the
aqueous extract of the leaves of Flacourtia indica protects liver
against oxidative damages and could be used as an effective protector
against CCl4 induced hepatic damage. Our findings suggested that
Flacourtia indica possessed good hepatoprotective activity
Abstract: Although oil-based drilling fluids are of paramount practical and economical interest, they represent a serious source of pollution, once released into the environment as drill cuttings. The aim of this study is to assess the capability of isolated microorganisms to degrade gasoil fuel. The commonly used physicochemical and biodegradation remediation techniques of petroleum contaminated soil were both investigated. The study revealed that natural biodegradation is favorable. Even though, the presence of heavy metals, the moisture level of (8.55%) and nutrient deficiencies put severe constrains on microorganisms- survival ranges inhibiting the biodegradation process. The selected strains were able to degrade the diesel fuel at significantly high rates (around 98%).
Abstract: The concentrations of aliphatic and polycyclic aromatic hydrocarbons (PAH) were determined in atmospheric aerosol samples collected at a rural site in Hungary (K-puszta, summer 2008), a boreal forest (Hyytiälä,
April 2007) and a polluted rural area in Italy (San Pietro Capofiume, Po Valley, April 2008). A clear distinction between “clean" and “polluted" periods was observed. Concentrations obtained for Hyytiälä are significantly lower than those for the other two sites. Source reconciliation was performed using diagnostic parameters, such as the carbon preference index and ratios between PAH. The presence of an unresolved complex mixture of hydrocarbons, especially for the Finnish and Italian samples, is indicative of petrogenic inputs. In K-puszta, the aliphatic hydrocarbons are dominated by leaf wax n-alkanes. The long range transport of anthropogenic pollution contributed to the Finnish aerosol. Industrial activities and vehicular emissions represent major sources in San Pietro Capofiume. PAH in K-puszta consist of both pyrogenic and petrogenic compounds.
Abstract: To reduce the carbon dioxide emission into the
atmosphere, adsorption is believed to be one of the most attractive
methods for post-combustion treatment of flue gas. In this work,
activated carbon (AC) was modified by polyethylenimine (PEI) via
impregnation in order to enhance CO2 adsorption capacity. The
adsorbents were produced at 0.04, 0.16, 0.22, 0.25, and 0.28 wt%
PEI/AC. The adsorption was carried out at a temperature range from
30 °C to 75 °C and five different gas pressures up to 1 atm. TG-DTA,
FT-IR, UV-visible spectrometer, and BET were used to characterize
the adsorbents. Effects of PEI loading on the AC for the CO2
adsorption were investigated. Effectiveness of the adsorbents on the
CO2 adsorption including CO2 adsorption capacity and adsorption
temperature was also investigated. Adsorption capacities of CO2 were
enhanced with the increase in the amount of PEI from 0.04 to 0.22
wt% PEI before the capacities decreased onwards from0.25 wt% PEI
at 30 °C. The 0.22 wt% PEI/AC showed higher adsorption capacity
than the AC for adsorption at 50 °C to 75 °C.
Abstract: Due to the environmental and price issues of current
energy crisis, scientists and technologists around the globe are
intensively searching for new environmentally less-impact form of
clean energy that will reduce the high dependency on fossil fuel.
Particularly hydrogen can be produced from biomass via thermochemical
processes including pyrolysis and gasification due to the
economic advantage and can be further enhanced through in-situ
carbon dioxide removal using calcium oxide. This work focuses on
the synthesis and development of the flowsheet for the enhanced
biomass gasification process in PETRONAS-s iCON process
simulation software. This hydrogen prediction model is conducted at
operating temperature between 600 to 1000oC at atmospheric
pressure. Effects of temperature, steam-to-biomass ratio and
adsorbent-to-biomass ratio were studied and 0.85 mol fraction of
hydrogen is predicted in the product gas. Comparisons of the results
are also made with experimental data from literature. The
preliminary economic potential of developed system is RM 12.57 x
106 which equivalent to USD 3.77 x 106 annually shows economic
viability of this process.
Abstract: Deoxygenation of beef fat for the production of hydrogenated biodiesel is investigated in a high pressure continuous flow fixed bed reactor over palladium-supported mesoporous titania catalyst synthesized via a combined single-step sol-gel process with surfactant-assisted templating method (SATM). The catalyst possessed a mesoporous charactheristic with high surface area and narrow pore size distribution. The main products of all Pd/TiO2 catalysts are n-heptadecane (n-C17) and n-pentadecane (n-C15) resulting from decarbonylation reaction. Pd/TiO2 catalyst synthesized via a combined single-step sol-gel process with SATM (SSSG) gave higher activity and selectivity to the desired products when compared to IWI/SG-TiO2 and IWI/P25-TiO2, respectively. SSSG catalyst gave the average conversion up to 80-90 % and 80 % for the selectivity in diesel range hydrocarbons. This result may cause by the higher surface area and the ability in dispersion of palladium ion in mesoporous of TiO2 during sol-gel process.
Abstract: A large quantity of world-s oil reserves exists in
carbonate reservoirs. Carbonate reservoirs are very sensitive to
chemical enhanced oil recovery process because of containing large
amount of calcite, dolomite and calcium sulfate minerals. These
minerals cause major obstacles during alkali-surfactant-polymer
(ASP) flooding. Alkali reacts with these minerals and form undesired
precipitations which plug effective porous openings, reduce
permeability and cause scale occurrence at the wellbore. In this
paper, a new chemical combination consists of acrylic acid and alkali
was used to minimize precipitation problem during ASP flooding. A
series of fluid-fluid compatibility tests were performed using acrylic
acid and different concentrations of alkaline. Two types of alkalis
namely; sodium carbonate and sodium metaborate were screened. As
a result, the combination of acrylic acid and sodium carbonate was
not effective in preventing calcium and magnesium precipitations.
However, acrylic acid and sodium metaborate showed promising
results for keeping all solutions without any precipitations. The ratio
of acrylic acid to sodium metaborate of 0.7:1.0 was found to be
optimum for achieving a compatible solution for 30 days at 80oC.