Abstract: This study evaluates the performance of horizontal
subsurface flow constructed wetland (HSSF-CW) for the removal of
chlorinated resin and fatty acids (RFAs) from pulp and paper mill
wastewater. The dimensions of the treatment system were 3.5 m x 1.5
m x 0.28 m with surface area of 5.25 m2, filled with fine sand and
gravel. The cell was planted with an ornamental plant species Canna
indica. The removal efficiency of chlorinated RFAs was in the range
of 92-96% at the hydraulic retention time (HRT) of 5.9 days. Plant
biomass and soil (sand and gravel) were analyzed for chlorinated
RFAs content. No chlorinated RFAs were detected in plant biomass
but detected in soil samples. Mass balance studies of chlorinated
RFAs in HSSF-CW were also carried out.
Abstract: The oleaginous yeasts Lipomyces starkey were grown
in the presence of dairy industry wastewaters (DIW). The yeasts were
able to degrade the organic components of DIW and to produce a
significant fraction of their biomass as triglycerides.
When using DIW from the Ricotta cheese production or residual
whey as growth medium, the L. starkey could be cultured without
dilution nor external organic supplement. On the contrary, the yeasts
could only partially degrade the DIW from the Mozzarella cheese
production, due to the accumulation of a metabolic product beyond
the threshold of toxicity. In this case, a dilution of the DIW was
required to obtain a more efficient degradation of the carbon
compounds and an higher yield in oleaginous biomass.
The fatty acid distribution of the microbial oils obtained showed a
prevalence of oleic acid, and is compatible with the production of a II
generation biodiesel offering a good resistance to oxidation as well as
an excellent cold-performance.
Abstract: A local wastewater treatment plant (WWTP)
experiencing poor nitrification tracked down high level of
surfactants in the plant-s influent and effluent. The aims of this project were to assess the potential inhibitory effect of surfactants on activated sludge processes. The effect of the
presence of TergitolNP-9, TrigetolNP-7, Trigetol15-S-9,
dodecylbenzene sulphonate (SDBS) and sodium dodecyl
sulfate (SDS) on activated sludge oxygen uptake rate (OUR) and nitrification were assessed. The average concentration of non-ionic and anionic
surfactants in the influent to the local WWTP were 7 and 8.7 mg/L, respectively. Removal of 67% to 90% of the non-ionic and 93-99% of the anionic surfactants tested were measured. All surfactants tested showed inhibitory effects both on OUR
and nitrification. SDS incurred the lowest inhibition whereas
SDBS and NP-9 caused severe inhibition to OUR and
Nitrification. Activated sludge flocs sizes slightly decreased
after 3 hours contact with the surfactant present in the test.
The results obtained indicated that high concentrations of
surfactants are likely to have an adverse effect on the
performance of WWTPs utilizing activated sludge processes.
Abstract: Short message integrated distributed monitoring systems (SM-DMS) are growing rapidly in wireless communication applications in various areas, such as electromagnetic field (EMF) management, wastewater monitoring, and air pollution supervision, etc. However, delay in short messages often makes the data embedded in SM-DMS transmit unreliably. Moreover, there are few regulations dealing with this problem in SMS transmission protocols. In this study, based on the analysis of the command and data requirements in the SM-DMS, we developed a processing model for the control center to solve the delay problem in data transmission. Three components of the model: the data transmission protocol, the receiving buffer pool method, and the timer mechanism were described in detail. Discussions on adjusting the threshold parameter in the timer mechanism were presented for the adaptive performance during the runtime of the SM-DMS. This model optimized the data transmission reliability in SM-DMS, and provided a supplement to the data transmission reliability protocols at the application level.
Abstract: Laboratory experiments have been performed to investigate photocatalytic detoxification by using TiO2 photocatalyst for treating dairy effluent. Various operational parameters such as catalyst concentration, initial concentration, angle of tilt of solar flat plate reactor and flow rate were investigated. Results indicated that the photocatalytic detoxification process can efficiently treat dairy effluent. Experimental runs with dairy wastewater can be used to identify the optimum operational parameters to perform wastewater degradation on large scale for recycling purpose. Also effect of two different types of reactors on degradation process was analyzed.
Abstract: In this study, the reduction of Cr(VI) by use of scrap
iron, a cheap and locally available industrial waste, was investigated
in continuous system. The greater scrap iron efficiency observed for
the first two sections of the column filling indicate that most of the
reduction process was carried out in the bottom half of the column
filling. This was ascribed to a constant decrease of Cr(VI)
concentration inside the filling, as the water front passes from the
bottom to the top end of the column. While the bottom section of the
column filling was heavily passivated with secondary mineral phases,
the top section was less affected by the passivation process; therefore
the column filling would likely ensure the reduction of Cr(VI) for
time periods longer than 216 hours. The experimental results indicate
that fixed beds columns packed with scrap iron could be successfully
used for the first step of Cr(VI) polluted wastewater treatment.
However, the mass of scrap iron filling should be carefully estimated
since it significantly affects the Cr(VI) reduction efficiency.
Abstract: In this work, biohydrogen production via dark
fermentation from alcohol wastewater using upflow anaerobic sludge
blanket reactors (UASB) with a working volume of 4 L was
investigated to find the optimum conditions for a maximum hydrogen
yield. The system was operated at different COD loading rates (23,
31, 46 and 62 kg/m3d) at mesophilic temperature (37 ºC) and pH 5.5.
The seed sludge was pretreated before being fed to the UASB system
by boiling at 95 ºC for 15 min. When the system was operated under
the optimum COD loading rate of 46 kg/m3d, it provided the
hydrogen content of 27%, hydrogen yield of 125.1 ml H2/g COD
removed and 95.1 ml H2/g COD applied, hydrogen production rate of
18 l/d, specific hydrogen production rate of 1080 ml H2/g MLVSS d
and 1430 ml H2/ L d, and COD removal of 24%.
Abstract: The effects of irrigation with dairy factory wastewater
on soil properties were investigated at two sites that had received
irrigation for > 60 years. Two adjoining paired sites that had never
received DFE were also sampled as well as another seven fields from
a wider area around the factory. In comparison with paired sites that
had not received effluent, long-term wastewater irrigation resulted in
an increase in pH, EC, extractable P, exchangeable Na and K and
ESP. These changes were related to the use of phosphoric acid,
NaOH and KOH as cleaning agents in the factory. Soil organic C
content was unaffected by DFE irrigation but the size (microbial
biomass C and N) and activity (basal respiration) of the soil
microbial community were increased. These increases were
attributed to regular inputs of soluble C (e.g. lactose) present as milk
residues in the wastewater. Principal component analysis (PCA) of
the soils data from all 11sites confirmed that the main effects of DFE
irrigation were an increase in exchangeable Na, extractable P and
microbial biomass C, an accumulation of soluble salts and a liming
effect. PCA analysis of soil bacterial community structure, using
PCR-DGGE of 16S rDNA fragments, generally separated individual
sites from one another but did not group them according to irrigation
history. Thus, whilst the size and activity of the soil microbial
community were increased, the structure and diversity of the
bacterial community remained unaffected.
Abstract: An HPLC-UV analytical method was developed to
determine ethylenediaminetetraacetic acid (EDTA) in dairy
wastewater and surface water. The optimizing separation was achieved
by reversed–phase ion-pair liquid chromatography on a C18 column
using methanol as mobile phase solvent, tetrabutylammonium bromide
as the ion-pair reagent in pH 3.3 formate buffer solution at a flow rate
of 0.9 mL min-1 with a UV detector at 265 nm. No interference of Ca,
Mg or NO3
- was detected. Method performance was evaluated in terms
of linearity, repeatability and reproducibility. The method detection
limit was 5 μg L-1. The contents of EDTA in dairy effluents were 72 ~
261 μg L-1 at a large dairy site. A change of EDTA concentration was
observed downstream of the dairy effluent discharge, but this was well
under the predicted no effect concentration for aquatic ecosystem.
Abstract: Porcine production in China represents approximately
the 50% of the worldwide pig production. Information about pig
husbandry characteristics in China and manure properties from sows
to fatteners in intensive pig farms are not broadly available for
scientific studies as it is a time consuming, expensive task and highly
inaccessible. This study provides a report about solid pig manures
(28% dry matter) in a commercial pig farm located in the peri-urban
area of Beijing as well as a general overview of the current pig
husbandry techniques including pig breeds, feeds, diseases, housing as
well as pig manure and wastewater disposal. The main results are
intended to serve as a literature source for young scientists in order to
understand the main composition of pig manures as well as to identify
the husbandry techniques applied in an intensive pig farm in Beijing.
Abstract: The agriculture lignocellulosic by-products are receiving increased attention, namely in the search for filter materials that retain contaminants from water. These by-products, specifically almond and hazelnut shells are abundant in Portugal once almond and hazelnuts production is a local important activity. Hazelnut and almond shells have as main constituents lignin, cellulose and hemicelluloses, water soluble extractives and tannins. Along the adsorption of heavy metals from contaminated waters, water soluble compounds can leach from shells and have a negative impact in the environment. Usually, the chemical characterization of treated water by itself may not show environmental impact caused by the discharges when parameters obey to legal quality standards for water. Only biological systems can detect the toxic effects of the water constituents. Therefore, the evaluation of toxicity by biological tests is very important when deciding the suitability for safe water discharge or for irrigation applications.
The main purpose of the present work was to assess the potential impacts of waters after been treated for heavy metal removal by hazelnut and almond shells adsorption systems, with short term acute toxicity tests.
To conduct the study, water at pH 6 with 25 mg.L-1 of lead, was treated with 10 g of shell per litre of wastewater, for 24 hours. This procedure was followed for each bark. Afterwards the water was collected for toxicological assays; namely bacterial resistance, seed germination, Lemna minor L. test and plant grow. The effect in isolated bacteria strains was determined by disc diffusion method and the germination index of seed was evaluated using lettuce, with temperature and humidity germination control for 7 days. For aquatic higher organism, Lemnas were used with 4 days contact time with shell solutions, in controlled light and temperature. For terrestrial higher plants, biomass production was evaluated after 14 days of tomato germination had occurred in soil, with controlled humidity, light and temperature.
Toxicity tests of water treated with shells revealed in some extent effects in the tested organisms, with the test assays showing a close behaviour as the control, leading to the conclusion that its further utilization may not be considered to create a serious risk to the environment.
Abstract: Since water resources of desert Naein City are very
limited, a approach which saves water resources and meanwhile
meets the needs of the greenspace for water is to use city-s sewage
wastewater. Proper treatment of Naein-s sewage up to the standards
required for green space uses may solve some of the problems of
green space development of the city. The present paper closely
examines available statistics and information associated with city-s
sewage system, and determines complementary stages of sewage
treatment facilities of the city. In the present paper, population, per
capita water use, and required discharge for various greenspace
pieces including different plants are calculated. Moreover, in order to
facilitate the application of water resources, a Crude water
distribution network apart from drinking water distribution network is
designed, and a plan for mixing municipal wells- water with sewage
wastewater in proposed mixing tanks is suggested. Hence, following
greenspace irrigation reform and complementary plan, per capita
greenspace of the city will be increased from current amount of 13.2
square meters to 32 square meters.
Abstract: CTMA-bentonite and BTEA-Bentonite prepared by Na-bentonite cation exchanged with cetyltrimethylammonium(CTMA) and benzyltriethylammonium (BTEA). Products were characterized by XRD and IR techniques.The d001 spacing value of CTMA-bentonite and BTEA-bentonite are 7.54Å and 3.50Å larger than that of Na-bentonite at 100% cation exchange capacity, respectively. The IR spectrum showed that the intensities of OH stretching and bending vibrations of the two organoclays decreased greatly comparing to untreated Na-bentonite. Batch experiments were carried out at 303 K, 318 K and 333 K to obtain the sorption isotherms of Crystal violet onto the two organoclays. The results show that the sorption isothermal data could be well described by Freundlich model. The dynamical data for the two organoclays fit well with pseudo-second-order kinetic model. The adsorption capacity of CTMA-bentonite was found higher than that of BTEA-Bentonite. Thermodynamic parameters such as changes in the free energy (ΔG°), the enthalpy (ΔH°) and the entropy (ΔS°) were also evaluated. The overall adsorption process of Crystal violet onto the two organoclays were spontaneous, endothermic physisorption. The CTMA-bentonite and BTEA-Bentonite could be employed as low-cost alternatives to activated carbon in wastewater treatment for the removal of color which comes from textile dyes.
Abstract: The problem of wastewater treatment in Egypt is a two-fold problem; the first part concerning the existing rural areas, the second one dealing with new industrial/domestic areas. In Egypt several agricultural projects have been initiated by the government and the private sector as well, in order to change its infrastructure. As a reliable energy source, photovoltaic pumping systems have contributed to supply water for local rural communities worldwide; they can also be implemented to solve the problem “wastewater environment pollution". The solution of this problem can be categorised as recycle process. In addition, because of regional conditions past technologies are being reexamined to select a smallscale treatment system requiring low construction and maintenance costs. This paper gives the design guidelines of a Photovoltaic Small- Scale Wastewater Treatment Plant (PVSSWTP) based on technologies that can be transferred.
Abstract: The Bangnanglee Sub-district Administrative Office,
Thailand had initiated a policy to environmental protection with
encouraging household waste management in order to promote civil
responsibility for domestic hygienic. This research studied the
household behaviors on solid waste and wastewater management. A
sample population of 306 families answered a questionnaire. The
study showed that, on average, domestic activities had produced 1.93
kilograms of waste per household per day. It has been found that 79%
of the households made several attempts to reduce their own amount
of waste. 80% of the households stationed their own garbage bins.
71% managed their waste by selling recyclable products. As for the
rest of the waste, 51% burned them, while 29% disposed their waste
in the nearby public trashcans and other 13% have them buried. As
for wastewater, 60% of the households disposed it into the sewage,
whereas 30% disposed them right from their elevated house.
Abstract: The estimation of overall on-site and off-site greenhouse gas (GHG) emissions by wastewater treatment plants revealed that in anaerobic and hybrid treatment systems greater emissions result from off-site processes compared to on-site processes. However, in aerobic treatment systems, onsite processes make a higher contribution to the overall GHG emissions. The total GHG emissions were estimated to be 1.6, 3.3 and 3.8 kg CO2-e/kg BOD in the aerobic, anaerobic and hybrid treatment systems, respectively. In the aerobic treatment system without the recovery and use of the generated biogas, the off-site GHG emissions were 0.65 kg CO2-e/kg BOD, accounting for 40.2% of the overall GHG emissions. This value changed to 2.3 and 2.6 kg CO2-e/kg BOD, and accounted for 69.9% and 68.1% of the overall GHG emissions in the anaerobic and hybrid treatment systems, respectively. The increased off-site GHG emissions in the anaerobic and hybrid treatment systems are mainly due to material usage and energy demand in these systems. The anaerobic digester can contribute up to 100%, 55% and 60% of the overall energy needs of plants in the aerobic, anaerobic and hybrid treatment systems, respectively.
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: The ionizing radiation of livestock wastewater for the
removal of nitrogen and phosphorus was studied in the presence of a
natural zeolite. The feasibility of a combined process of zeolite ion
exchange and electron beam irradiation of livestock wastewater was
also investigated. The removal efficiencies of NH4
+-N, T-N and T-P
were significantly enhanced by electron beam irradiation after zeolite
ion exchange as a pre-treatment. The presence of silica zeolite
accelerated the decomposition rate of livestock wastewater in the
electron beam irradiation process. These results indicate that the
combined process of zeolite ion exchange and electron beam
irradiation has the potential for the treatment of livestock wastewater
Abstract: Thirty six samples from each (aerobic and anoxic)
activated sludge were collected from two wastewater treatment plants
with MBRs in Berlin, Germany. The samples were prepared for count
and definition of fungal isolates; these isolates were purified by
conventional techniques and identified by microscopic examination.
Sixty tow species belonging to 28 genera were isolated from
activated sludge samples under aerobic conditions (28 genera and 58
species) and anoxic conditions (26 genera and 52 species). The
obtained data show that, Aspergillus was found at 94.4% followed by
Penicillium 61.1 %, Fusarium (61.1 %), Trichoderma (44.4 %) and
Geotrichum candidum (41.6 %) species were the most prevalent in all
activated sludge samples. The study confirmed that fungi can thrive
in activated sludge and sporulation, but isolated in different numbers
depending on the effect of aeration system. Some fungal species in
our study are saprophytic, and other a pathogenic to plants and
animals.
Abstract: This paper describes technological possibilities to
enhance methane productionin the anaerobic stabilization of wastewater treatment plant excess sludge. This objective can be achieved by the addition of waste residues: crude glycerol from biodiesel production and residues from fishery. The addition
ofglycerol in an amount by weight of 2 – 5% causes enhancement of methane production of about 250 – 400%. At the same time the
percentage increase of total solids concentration in the outgoing sludge is ten or more times less. The containment of methane in
biogas is higher in case of admixed substrate.