Abstract: Some of the polycyclic aromatic hydrocarbons (PAHs)
are the strongest known carcinogens compounds; the majority of
them are mostly produced by the incomplete combustion of fossil
fuels; Motor vehicles are a significant source of polycyclic aromatic
hydrocarbon (PAH) where diesel emission is one of the main sources
of such compounds available in the ambient air. There is a big
concern about the increasing concentration of PAHs in the
environment. Researchers are trying to explore optimal methods to
reduce those pollutants and improve the quality of air. Water blended
fuel is one of the possible approaches to reduce emission of PAHs
from the combustion of diesel in urban and domestic vehicles. In this
work a modeling study was conducted using CHEMKIN-PRO
software to simulate spray combustion at similar diesel engine
conditions. Surrogate fuel of (80 % n-heptane and 20 % toluene) was
used due to detailed kinetic and thermodynamic data needed for
modeling is available for this kind of fuel but not available for diesel.
An emulsified fuel with 3, 5, 8, 10 and 20 % water by volume is used
as an engine feed for this study. The modeling results show that water
has a significant effect on reducing engine soot and PAHs precursors
formation up to certain extent.
Abstract: The environment pollution with pesticides and heavy
metals is a recognized problem nowadays, with extension to the
global scale the tendency of amplification. Even with all the progress
in the environmental field, both in the emphasize of the effect of the
pollutants upon health, the linked studies environment-health are
insufficient, not only in Romania but all over the world also. We aim
to describe the particular situation in Romania regarding the
uncontrolled use of pesticides, to identify and evaluate the risk zones
for health and the environment in Romania, with the final goal of
designing adequate programs for reduction and control of the risk
sources. An exploratory study was conducted to determine the
magnitude of the pesticide use problem in a population living in
Saliste, a rural setting in Transylvania, Romania. The significant
stakeholders in Saliste region were interviewed and a sample from
the population living in Saliste area was selected to fill in a designed
questionnaire. All the selected participants declared that they used
pesticides in their activities for more than one purpose. They
declared they annually applied pesticides for a period of time
between 11 and 30 years, from 5 to 9 days per year on average,
mainly on crops situated at some distance from the houses but high
risk behavior was identified as the volunteers declared the use of
pesticides in the backyard gardens, near their homes, where children
were playing. The pesticide applicators did not have the necessary
knowledge about safety and exposure. The health data must be
correlated with exposure biomarkers in attempt to identify the
possible health effects of the pesticides exposure. Future plans
include educational campaigns to raise the awareness of the
population on the danger of uncontrolled use of pesticides.
Abstract: The combustion chamber dimensions have important
effects on pollutant emission in furnaces as a direct result of
temperature distribution and maximum temperature value. In this
paper the pollutant emission and the temperature distribution in two
cylindrical furnaces with different dimensions (with similar length to
diameter ratio) in similar condition have been investigated
experimentally. The furnace fuel is gas oil that is used with three
different flow rates. The results show that in these two cases the
temperature increases to its maximum value quickly, and then
decreases slowly. The results also show that increase in fuel flow rate
cause to increase in NOx emission in each case, but this increase is
greater in small furnace. With increase in fuel flow rate, CO emission
decreases firstly, and then it increases. Combustion efficiency
reduces with increase in fuel flow rate but the rate of reduction in
small furnace is greater than large furnace. The results of axial
temperature distribution have been compared with those have been
obtained numerically and experimentally by Moghiman.
Abstract: The aim of this study was to develop a storm water quality improvement strategy plan (WQISP) which assists managers and decision makers of local city councils in enhancing their activities to improve regional water quality. City of Gosnells in Western Australia has been considered as a case study. The procedure on developing the WQISP consists of reviewing existing water quality data, identifying water quality issues in the study areas and developing a decision making tool for the officers, managers and decision makers. It was found that land use type is the main factor affecting the water quality. Therefore, activities, sources and pollutants related to different land use types including residential, industrial, agricultural and commercial are given high importance during the study. Semi-structured interviews were carried out with coordinators of different management sections of the regional councils in order to understand the associated management framework and issues. The issues identified from these interviews were used in preparing the decision making tool. Variables associated with the defined “value versus threat" decision making tool are obtained from the intensive literature review. The main recommendations provided for improvement of water quality in local city councils, include non-structural, structural and management controls and potential impacts of climate change.
Abstract: 17α-ethinylestradiol (EE2) is a recalcitrant micropollutant which is found in small amounts in municipal wastewater. But these small amounts still adversely affect for the reproductive function of aquatic organisms. Evidence in the past suggested that full-scale WWTPs equipped with nitrification process enhanced the removal of EE2 in the municipal wastewater. EE2 has been proven to be able to be transformed by ammonia oxidizing bacteria (AOB) via co-metabolism. This research aims to clarify the EE2 degradation pattern by different consortium of ammonia oxidizing microorganism (AOM) including AOA (ammonia oxidizing archaea) and investigate contribution between the existing ammonia monooxygenase (AMO) and new synthesized AOM. The result showed that AOA or AOB of N. oligotropha cluster in enriched nitrifying activated sludge (NAS) from 2mM and 5mM, commonly found in municipal WWTPs, could degrade EE2 in wastewater via co-metabolism. Moreover, the investigation of the contribution between the existing ammonia monooxygenase (AMO) and new synthesized AOM demonstrated that the new synthesized AMO enzyme may perform ammonia oxidation rather than the existing AMO enzyme or the existing AMO enzyme may has a small amount to oxidize ammonia.
Abstract: ZnO nanocrystals with mean diameter size 14 nm
have been prepared by precipitation method, and examined as
photocatalyst for the UV-induced degradation of insecticide diazinon
as deputy of organic pollutant in aqueous solution. The effects of
various parameters, such as illumination time, the amount of
photocatalyst, initial pH values and initial concentration of
insecticide on the photocatalytic degradation diazinon were
investigated to find desired conditions. In this case, the desired
parameters were also tested for the treatment of real water containing
the insecticide. Photodegradation efficiency of diazinon was
compared between commercial and prepared ZnO nanocrystals. The
results indicated that UV/ZnO process applying prepared
nanocrystalline ZnO offered electrical energy efficiency and
quantum yield better than commercial ZnO. The present study, on the
base of Langmuir-Hinshelwood mechanism, illustrated a pseudo
first-order kinetic model with rate constant of surface reaction equal
to 0.209 mg l-1 min-1 and adsorption equilibrium constant of 0.124 l
mg-1.
Abstract: This paper present an efficient and reliable technique of optimization which combined fuel cost economic optimization and emission dispatch using the Sigmoid Decreasing Inertia Weight Particle Swarm Optimization algorithm (PSO) to reduce the cost of fuel and pollutants resulting from fuel combustion by keeping the output of generators, bus voltages, shunt capacitors and transformer tap settings within the security boundary. The performance of the proposed algorithm has been demonstrated on IEEE 30-bus system with six generating units. The results clearly show that the proposed algorithm gives better and faster speed convergence then linearly decreasing inertia weight.
Abstract: The objectives of this study are to determine the
effects of soil cover type on characteristics of leachates generated
from landfill lysimeters. Four lysimeters with diameter and height
of 0.15 and 3.00 m, respectively, were prepared. Three lysimeters
were filled with municipal waste and three different cover soil types
i.e. sandy loam soil, silty loam soil and clay soil while another
lysimeter was filled solely with municipal waste. The study was
conducted in the rainy season. Leachate quantities were measured
every day and leachate characteristics were determined once a week.
The cumulative leachate quantity from the lysimeter filled solely
with municipal waste was found to be around 27% higher than the
lysimeters using cover soils. There were no any differences of the
cumulative leachate amounts generated from the lysimeters using
three types of soils. The comparison of the total mass of pollutants
generated from all lysimeters showed that the lysimeter filled solely
with municipal waste generated the maximum quantities of
pollutants. Among the lysimeters using different types of soils, the
lysimeter using sandy loam soil generated the lowest amount of most
of pollutants, compared with the lysimeters using silty loam and clay
soils. It can be concluded that in term of pollutant attenuation in the
leachate, a sandy loam is the most suitable soil to be used as a cover
soil in the landfill.
Abstract: Ground-level tropospheric ozone is one of the air
pollutants of most concern. It is mainly produced by photochemical
processes involving nitrogen oxides and volatile organic compounds
in the lower parts of the atmosphere. Ozone levels become
particularly high in regions close to high ozone precursor emissions
and during summer, when stagnant meteorological conditions with
high insolation and high temperatures are common.
In this work, some results of a study about urban ozone
distribution patterns in the city of Badajoz, which is the largest and
most industrialized city in Extremadura region (southwest Spain) are
shown. Fourteen sampling campaigns, at least one per month, were
carried out to measure ambient air ozone concentrations, during
periods that were selected according to favourable conditions to
ozone production, using an automatic portable analyzer.
Later, to evaluate the ozone distribution at the city, the measured
ozone data were analyzed using geostatistical techniques. Thus, first,
during the exploratory analysis of data, it was revealed that they were
distributed normally, which is a desirable property for the subsequent
stages of the geostatistical study. Secondly, during the structural
analysis of data, theoretical spherical models provided the best fit for
all monthly experimental variograms. The parameters of these
variograms (sill, range and nugget) revealed that the maximum
distance of spatial dependence is between 302-790 m and the
variable, air ozone concentration, is not evenly distributed in reduced
distances. Finally, predictive ozone maps were derived for all points
of the experimental study area, by use of geostatistical algorithms
(kriging). High prediction accuracy was obtained in all cases as
cross-validation showed. Useful information for hazard assessment
was also provided when probability maps, based on kriging
interpolation and kriging standard deviation, were produced.
Abstract: This paper puts forward one kind of air-fuel ratio
control method with PI controller. With the help of
MATLAB/SIMULINK software, the mathematical model of air-fuel
ratio control system for distributorless CNG engine is constructed.
The objective is to maintain cylinder-to-cylinder air-fuel ratio at a
prescribed set point, determined primarily by the state of the Three-
Way-Catalyst (TWC), so that the pollutants in the exhaust are
removed with the highest efficiency. The concurrent control of airfuel
under transient conditions could be implemented by Proportional
and Integral (PI) controller. The simulation result indicates that the
control methods can easily eliminate the air/fuel maldistribution and
maintain the air/fuel ratio at the stochiometry within minimum
engine events.
Abstract: Atmospheric stability plays the most important role in
the transport and dispersion of air pollutants. Different methods are
used for stability determination with varying degrees of complexity.
Most of these methods are based on the relative magnitude of
convective and mechanical turbulence in atmospheric motions.
Richardson number, Monin-Obukhov length, Pasquill-Gifford
stability classification and Pasquill–Turner stability classification, are
the most common parameters and methods. The Pasquill–Turner
Method (PTM), which is employed in this study, makes use of
observations of wind speed, insolation and the time of day to classify
atmospheric stability with distinguishable indices. In this study, a
model is presented to determination of atmospheric stability
conditions using PTM. As a case study, meteorological data of
Mehrabad station in Tehran from 2000 to 2005 is applied to model.
Here, three different categories are considered to deduce the pattern
of stability conditions. First, the total pattern of stability classification
is obtained and results show that atmosphere is 38.77%, 27.26%,
33.97%, at stable, neutral and unstable condition, respectively. It is
also observed that days are mostly unstable (66.50%) while nights are
mostly stable (72.55%). Second, monthly and seasonal patterns are
derived and results indicate that relative frequency of stable
conditions decrease during January to June and increase during June
to December, while results for unstable conditions are exactly in
opposite manner. Autumn is the most stable season with relative
frequency of 50.69% for stable condition, whilst, it is 42.79%,
34.38% and 27.08% for winter, summer and spring, respectively.
Hourly stability pattern is the third category that points out that
unstable condition is dominant from approximately 03-15 GTM and
04-12 GTM for warm and cold seasons, respectively. Finally,
correlation between atmospheric stability and CO concentration is
achieved.
Abstract: Three dimensional simulations are carried out to estimate the effect of wind direction, wind speed and geometry on the flow and dispersion of vehicular pollutant in a street canyon. The pollutant sources are motor vehicles passing between the two buildings. Suitable emission factors for petrol and diesel vehicles at varying vehicle speed are used for the estimation of the rate of emission from the streets. The dispersion of automobile pollutant released from the street is simulated by introducing vehicular emission source term as a fixed-flux boundary condition at the ground level over the road. The emission source term is suitably calculated by adopting emission factors from literature for varying conditions of street traffic. It is observed that increase in wind angle disturbs the symmetric pattern of pollution distribution along the street length. The concentration increases in the far end of the street as compared to the near end.
Abstract: A physically based, spatially-distributed water quality model is being developed to simulate spatial and temporal distributions of material transport in the Great Lakes Watersheds of the U.S. Multiple databases of meteorology, land use, topography, hydrography, soils, agricultural statistics, and water quality were used to estimate nonpoint source loading potential in the study watersheds. Animal manure production was computed from tabulations of animals by zip code area for the census years of 1987, 1992, 1997, and 2002. Relative chemical loadings for agricultural land use were calculated from fertilizer and pesticide estimates by crop for the same periods. Comparison of these estimates to the monitored total phosphorous load indicates that both point and nonpoint sources are major contributors to the total nutrient loads in the study watersheds, with nonpoint sources being the largest contributor, particularly in the rural watersheds. These estimates are used as the input to the distributed water quality model for simulating pollutant transport through surface and subsurface processes to Great Lakes waters. Visualization and GIS interfaces are developed to visualize the spatial and temporal distribution of the pollutant transport in support of water management programs.
Abstract: A unique combination of adsorption and
electrochemical regeneration with a proprietary adsorbent material
called Nyex 100 was introduced at the University of Manchester for
waste water treatment applications. Nyex 100 is based on graphite
intercalation compound. It is non porous and electrically conducing
adsorbent material. This material exhibited very small BET surface
area i.e. 2.75 m2g-1, in consequence, small adsorptive capacities for
the adsorption of various organic pollutants were obtained. This work
aims to develop composite adsorbent material essentially capable of
electrochemical regeneration coupled with improved adsorption
characteristics. An organic dye, acid violet 17 was used as standard
organic pollutant. The developed composite material was
successfully electrochemically regenerated using a DC current of 1 A
for 60 minutes. Regeneration efficiency was maintained at around
100% for five adsorption-regeneration cycles.
Abstract: The Beshar River is one aquatic ecosystem, which is
located next to the city of Yasuj in southern Iran. The Beshar river
has been contaminated by industrial factories such as effluent of
sugar factory, agricultural and other activities in this region such as,
Imam Sajjad hospital, drainage from agricultural farms, Yasuj urban
surface runoff and effluent of wastewater treatment plants ,specially
Yasuj waste water treatment plant. In order to evaluate the effects of
these pollutants on the quality of the Beshar river, five monitoring
stations were selected along its course. The first station is located
upstream of Yasuj near the Dehnow village; stations 2 to 4 are
located east, south and west of city; and the 5th station is located
downstream of Yasuj. Several water quality parameters were
sampled. These include pH, dissolved oxygen, biological oxygen
demand (BOD), temperature, conductivity, turbidity, total dissolved
solids and discharge or flow measurements. Water samples from the
five stations were collected and analyzed to determine the following
physicochemical parameters: EC, pH, T.D.S, T.H, No2, DO, BOD5,
COD during 2008 to 2010. The study shows that the BOD5 value of
station 1 is at a minimum (1.7 ppm) and increases downstream from
stations 2 to 4 to a maximum (11.6 ppm), and then decreases at
station 5. The DO values of station 1 is a maximum (8.45 ppm),
decreases downstream to stations 2 - 4 which are at a minimum (3.1
ppm), before increasing at station 5. The amount of BOD and TDS
are highest at the 4th station and the amount of DO is lowest at this
station, marking the 4th station as more highly polluted than the
other stations .This study shows average amount of the water quality
parameters in first year of sampling (2008) have had a better quality
relation to third year in 2010 because of recent drought in this region
and pollutant increasing .As the Beshar river path after 5th station
goes through the mountain area with more slope and flow velocity
,so the physicochemical parameters improve at the 5th station due to
pollutant degradation and dilution. Finally the point and nonpoint
pollutant sources of Beshar river were determined and compared to
the monitoring results.
Abstract: The present paper was concerned primarily with the
analysis, simulation of the air flow and thermal patterns in a lecture
room. The paper is devoted to numerically investigate the influence
of location and number of ventilation and air conditioning supply and
extracts openings on air flow properties in a lecture room. The work
focuses on air flow patterns, thermal behaviour in lecture room where
large number of students. The effectiveness of an air flow system is
commonly assessed by the successful removal of sensible and latent
loads from occupants with additional of attaining air pollutant at a
prescribed level to attain the human thermal comfort conditions and
to improve the indoor air quality; this is the main target during the
present paper. The study is carried out using computational fluid
dynamics (CFD) simulation techniques as embedded in the
commercially available CFD code (FLUENT 6.2). The CFD
modelling techniques solved the continuity, momentum and energy
conservation equations in addition to standard k – ε model equations
for turbulence closure.
Throughout the investigations, numerical validation is carried out by
way of comparisons of numerical and experimental results. Good
agreement is found among both predictions.
Abstract: Data envelopment analysis (DEA) has gained great popularity in environmental performance measurement because it can provide a synthetic standardized environmental performance index when pollutants are suitably incorporated into the traditional DEA framework. Since some of the environmental performance indicators cannot be controlled by companies managers, it is necessary to develop the model in a way that it could be applied when discretionary and/or non-discretionary factors were involved. In this paper, we present a semi-radial DEA approach to measuring environmental performance, which consists of non-discretionary factors. The model, then, has been applied on a real case.
Abstract: Nanophotocatalysts such as titanium (TiO2), zinc (ZnO), and iron (Fe2O3) oxides can be used in organic pollutants oxidation, and in many other applications. But among the challenges for technological application (scale-up) of the nanotechnology scientific developments two aspects are still little explored: research on environmental risk of the nanomaterials preparation methods, and the study of nanomaterials properties and/or performance variability. The environmental analysis was performed for six different methods of ZnO nanoparticles synthesis, and showed that it is possible to identify the more environmentally compatible process even at laboratory scale research. The obtained ZnO nanoparticles were tested as photocatalysts, and increased the degradation rate of the Rhodamine B dye up to 30 times.
Abstract: “Garbage enzyme", a fermentation product of kitchen waste, water and brown sugar, is claimed in the media as a multipurpose solution for household and agricultural uses. This study assesses the effects of dilutions (5% to 75%) of garbage enzyme in reducing pollutants in domestic wastewater. The pH of the garbage enzyme was found to be 3.5, BOD concentration about 150 mg/L. Test results showed that the garbage enzyme raised the wastewater-s BOD in proportion to its dilution due to its high organic content. For mixtures with more than 10% garbage enzyme, its pH remained acidic after the 5-day digestion period. However, it seems that ammonia nitrogen and phosphorus could be removed by the addition of the garbage enzyme. The most economic solution for removal of ammonia nitrogen and phosphorus was found to be 9%. Further tests are required to understand the removal mechanisms of the ammonia nitrogen and phosphorus.
Abstract: Eutrophication of surface water is one of the most
widespread environmental problems at present. Large number of
pilgrims and tourists visit sacred artificial tank known as “Brahma
Sarover” located at Kurukshetra, India to take holy dip and perform
religious ceremonies. The sources of pollutants include impurities in
feed water, mass bathing, religious offerings and windblown
particulate matter. Studies so far have focused mainly on assessing
water quality for bathing purpose by using physico-chemical and
bacteriological parameters. No effort has been made to assess nutrient
concentration and trophic status of the tank to take more appropriate
measures for improving water quality on long term basis. In the
present study, total nitrogen, total phosphorous and chlorophyll a
measurements have been done to assess the nutrient level and trophic
status of the tank. The results show presence of high concentration of
nutrients and Chlorophyll a indicating mesotrophic and eutrophic
state of the tank. Phosphorous has been observed as limiting nutrient
in the tank water.