Search results for: dye degradation

Authors: Ahmad Aroziki Abdul Aziz, Sakinah Mohd Alauddin, Ruzitah Mohd Salleh, Mohammed Iqbal Shueb

Abstract:

This paper illustrates the effect of nano Magnesium Hydroxide (MH) loading on the thermal properties of Low Density Polyethylene (LDPE)/ Poly (ethylene-co vinyl acetate)(EVA) nano composite. Thermal studies were conducted, as it understanding is vital for preliminary development of new polymeric systems. Thermal analysis of nano composite was conducted using thermo gravimetric analysis (TGA), and differential scanning calorimetry (DSC). Major finding of TGA indicated two main stages of degradation process found at (350 ± 25 oC) and (480 ± 25 oC) respectively. Nano metal filler expressed better fire resistance as it stand over high degree of temperature. Furthermore, DSC analysis provided a stable glass temperature around 51 (±1 oC) and captured double melting point at 84 (±2 oC) and 108 (±2 oC). This binary melting point reflects the modification of nano filler to the polymer matrix forming melting crystals of folded and extended chain. The percent crystallinity of the samples grew vividly with increasing filler content. Overall, increasing the filler loading improved the degradation temperature and weight loss evidently and a better process and phase stability was captured in DSC.

Keywords: thermal properties, nano MH, nano particles, cable and wire, LDPE/EVA

Procedia PDF Downloads 437

Authors: Katarina Lazarević, Mirjana Todosijević, Tijana Vulević, Natalija Momirović, Ranka Erić

Abstract:

Due to increasing demand, climate change, and world population growth, natural resources are getting exploit fast. One of the most important natural resources is soil, which is susceptible to degradation. Erosion as one of the forms of land degradation is also one of the most global environmental problems. Ecosystem services are often defined as benefits that nature provides to humankind. Soil, as the foundation of basic ecosystem functions, provides benefits to people, erosion control, water infiltration, food, fuel, fibers… This research is using the ecosystem approach as a strategy for natural resources management for promoting sustainability and conservation. The research was done on the Topčiderska River basin (Belgrade, Serbia). The InVEST Sediment Delivery Ratio model was used, to quantify erosion intensity with a spatial distribution output map of overland sediment generation and delivery to the stream. InVEST SDR, a spatially explicit model, is using a method based on the concept of hydrological connectivity and (R) USLE model. This, combined with socio-economic and law and policy analysis, gives a full set of information to decision-makers helping them to successfully manage and deliver sustainable ecosystems.

Keywords: ecosystem services, InVEST model, soil erosion, sustainability

Procedia PDF Downloads 123

Authors: Sachil Kumar, Anoop K.Verma, Uma Shankar Singh

Abstract:

It’s extremely important to study postmortem interval in different causes of death since it assists in a great way in making an opinion on the exact cause of death following such incident often times. With diligent knowledge of the interval one could really say as an expert that the cause of death is not feigned hence there is a great need in evaluating such death to have been at the CRIME SCENE before performing an autopsy on such body. The approach described here is based on analyzing the degradation or proteolysis of a cardiac protein in cases of deaths due to burn as a marker of time since death. Cardiac tissue samples were collected from (n=6) medico-legal autopsies, (Department of Forensic Medicine and Toxicology), King George’s Medical University, Lucknow India, after informed consent from the relatives and studied post-mortem degradation by incubation of the cardiac tissue at room temperature (20±2 OC) for different time periods (~7.30, 18.20, 30.30, 41.20, 41.40, 54.30, 65.20, and 88.40 Hours). The cases included were the subjects of burn without any prior history of disease who died in the hospital and their exact time of death was known. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS-PAGE) and visualization by Western blot using cTnT specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc. As time postmortem progresses the intact cTnT band degrades to fragments that are easily detected by the monoclonal antibodies. A decreasing trend in the level of cTnT (% of intact) was found as the PM hours increased. A significant difference was observed between <15 h and other PM hours (p<0.01). Significant difference in cTnT level (% of intact) was also observed between 16-25 h and 56-65 h & >75 h (p<0.01). Western blot data clearly showed the intact protein at 42 kDa, three major (28 kDa, 30kDa, 10kDa) fragments, three additional minor fragments (12 kDa, 14kDa, and 15 kDa) and formation of low molecular weight fragments. Overall, both PMI and cardiac tissue of burned corpse had a statistically significant effect where the greatest amount of protein breakdown was observed within the first 41.40 Hrs and after it intact protein slowly disappears. If the percent intact cTnT is calculated from the total area integrated within a Western blot lane, then the percent intact cTnT shows a pseudo-first order relationship when plotted against the time postmortem. A strong significant positive correlation was found between cTnT and PM hours (r=0.87, p=0.0001). The regression analysis showed a good variability explained (R2=0.768) The post-mortem Troponin-T fragmentation observed in this study reveals a sequential, time-dependent process with the potential for use as a predictor of PMI in cases of burning.

Keywords: burn, degradation, postmortem interval, troponin-T

Procedia PDF Downloads 431

Authors: E. Roshan Ara Begum, K. Bhavani, K. Subachitra, C. Kirthika, R. Shenbagarathai

Abstract:

In recent years, there has been a growing concern for the production of chitosan blend nanofibrous scaffold for its favorable physicochemical properties which mimic the native extracellular matrix (ECM) both morphologically and chemically. Therefore, this study focused on production of β-chitosan(β-Cts) and Poly(vinyl alcohol)(PVA) blend nanofibrous scaffold by electrospinning. β-Cts was extracted from the squid pen waste of locally available squid variety Loligo duvauceli (Indian Squid). To the best of our knowledge, there are no reports on nanofibers preparation from the extracted β-Cts. Both the β-Cts and PVA polymers were mixed in two different proportions (30:70 and 40:60 respectively. The electrospun nanofibrous scaffolds were characterized by SEM, swelling property, in vitro enzymatic degradation, and hemo, biocompatibility properties. β-Cts/PVA nanofibers scaffolds had an average fiber diameter of 120 to 550nm.Among the two different β-Cts/PVA blends nanofibers the β-Cts/PVA (40:60) blend fibers demonstrated favourable tissue engineering properties. The β-Cts/PVA (40:60) blend nanofibers exhibited a swelling ratio of 36 ± 2.5% with mass loss percentage of 20 ± 2.71% after 4 weeks of degradation. It has exhibited good hemocompatible properties. HEK-293(Human Embryonic Kidney) cells lines were able to adhere and proliferate well in the β-Cts/PVA blends nanofibers. All these results indicated that electrospun β-Cts/PVA blends nanofibers are a suitable scaffold to be used for tissue engineering purposes.

Keywords: β-chitosan, electrospinning, nanofibers, poly(vinyl alcohol) (PVA)

Procedia PDF Downloads 221

Authors: Aisami A., Z. A. Adamu, Lawan Bulama

Abstract:

Due to growing issues of crude oil pollution in both marine and terrestrial environments, Billions to Trillions of US Dollars were spent over the years for the treatment of this spill. There is an urgent need for effective bioremediation strategies. This current study focuses on the isolation and characterization of a crude oil-degrading bacterium from hydrocarbon-contaminated soil samples. Soil samples were collected from an oil spill site and subjected to enrichment culture techniques in a mineral salt medium supplemented with crude oil as the singular carbon source. The isolates were screened for their crude oil-degrading capabilities using gravimetric analysis. The most efficient isolation was identified through 16S rRNA gene sequencing. Cultural and physical conditions such pH, temperature salinity and crude oil concentrations were optimized. The isolates showed significant crude oil degradation efficiency, reducing oil concentration (2.5%) by 75% within 15 days of incubation. The strain was identified as Providencia sp. through molecular characterization, the sequence was deposited at the NCBI Genbank with accession number MN880494. The bacterium exhibited optimal growth at 32.5°C, pH 7.0 to 7.5, and in the presence of 1.5% (w/v) NaCl. The isolated Providencia sp. shows encouraging potential for bioremediation of crude oil-contaminated environments. This study successfully isolated and characterized a crude oil-degrading Providencia sp., highlighting its potential in bioremediation.

Keywords: crude oil degradation, providencia sp., bioremediation, hydrocarbon utilization, environmental pollution.

Procedia PDF Downloads 7

Authors: Kaustuvmani Patowary, Suresh Deka

Abstract:

Oil pollution accidents, nowadays, have become a common phenomenon and have caused ecological and social disasters. Microorganisms with high oil-degrading performance are essential for bioremediation of petroleum hydrocarbon. In this investigation, an effective biosurfactant producer and hydrocarbon degrading bacterial strain, Pseudomonas sp.PG1 (identified by 16s rDNA sequencing) was isolated from hydrocarbon contaminated garage soil of Pathsala, Assam, India, using crude oil enrichment technique. The growth parameters such as pH and temperature were optimized for the strain and upto 81.8% degradation of total petroleum hydrocarbon (TPH) has been achieved after 5 weeks when grown in mineral salt media (MSM) containing 2% (w/v) crude oil as the carbon source. The biosurfactant production during the course of hydrocarbon degradation was monitored by surface tension measurement and emulsification activity. The produced biosurfactant had the ability to decrease the surface tension of MSM from 72 mN/m to 29.6 mN/m, with the critical micelle concentration (CMC)of 56 mg/L. The biosurfactant exhibited 100% emulsification activity on crude oil. FTIR spectroscopy and LCMS-MS analysis of the purified biosurfactant revealed that the biosurfactant is Rhamnolipidic in nature with several rhamnolipid congeners. Gas Chromatography-Mass spectroscopy (GC-MS) analysis clearly demonstrated that the strain PG1 efficiently degrade different hydrocarbon fractions of the crude oil. The study suggeststhat application of the biosurfactant producing strain PG1 as an appropriate candidate for bioremediation of crude oil contaminants.

Keywords: petroleum hydrocarbon, hydrocarbon contamination, bioremediation, biosurfactant, rhamnolipid

Procedia PDF Downloads 335

Authors: Sanjida Ahmed Sinthia

Abstract:

Bangladesh is one of the poorest countries in the world. There are several reasons for this insufficiency and uncontrolled population growth is one of the prime reasons. Others include low economic progress, imbalanced resource management, unemployment and underemployment, urban migration and natural catastrophes etc. As a result, the rate of urban poor is increasing inevitably in every sphere of urban cities in Bangladesh and Dhaka is the most affected one. Besides there is scarcity of urban land, housing, urban infrastructure and amenities which create pressure on urban cities and mostly encroach the open space, wetlands that causes environmental degradation. Government has no or limited control over these due to poor government policy and management, political pressure and lack of resource management. Unfortunately, over centralization and bureaucracy creates unnecessary delay and interruptions in any government initiations. There is also no coordination between government and private sector developer to solve the problem of urban Poor. To understand the problem of these huge populations this paper analyzes one of the single largest slum areas in Dhaka, Korail Slum. The study focuses on socio demographic analysis, morphological pattern and role of different actors responsible for the improvements of the area and recommended some possible steps for determining the potential outcomes.

Keywords: demographic analysis, environmental degradation, government policy, housing and land management policy

Procedia PDF Downloads 152

Authors: Luxi He, Tianfang Zhang, Zhengbin He, Songlin Yi

Abstract:

Heat treatment has been widely recognized for its effectiveness in enhancing the physicochemical properties of wood, including hygroscopicity and dimensional stability. Nonetheless, the non-negligible volumetric shrinkage and loss of mechanical strength resulting from heat treatment may diminish the wood recovery and its product value. In this study, tung oil was used to alleviate heat-induced shrinkage and reduction in mechanical properties of wood during heat treatment. Tung oil was chosen as a modifier because it is a traditional Chinese plant oil that has been widely used for over a thousand years to protect wooden furniture and buildings due to its biodegradable and non-toxic properties. The effects of different heating media (air, tung oil) and their effective treatment parameters (temperature, duration) on the changes in the physical properties (morphological characteristics, pore structures, micromechanical properties), and chemical properties (chemical structures, chemical composition) of wood were investigated by using scanning electron microscopy, confocal laser scanning microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and dynamic vapor sorption. Meanwhile, the correlation between the mass changes and the color change, volumetric shrinkage, and hygroscopicity was also investigated. The results showed that the thermal degradation of wood cell wall components was the most important factor contributing to the changes in heat-induced shrinkage, color, and moisture adsorption of wood. In air-heat-treated wood samples, there was a significant correlation between mass change and heat-induced shrinkage, brightness, and moisture adsorption. However, the presence of impregnated tung oil in oil-heat-treated wood appears to disrupt these correlations among physical properties. The results of micromechanical properties demonstrated a significant decrease in elastic modulus following high-temperature heat treatment, which was mitigated by tung oil treatment. Chemical structure and compositional analyses indicated that the changes in chemical structure primarily stem from the degradation of hemicellulose and cellulose, and the presence of tung oil created an oxygen-insulating environment that slowed down this degradation process. Morphological observation results showed that tung oil permeated the wood structure and penetrated the cell walls through transportation channels, altering the micro-morphology of the cell wall surface, obstructing primary water passages (e.g., vessels and pits), and impeding the release of volatile degradation products as well as the infiltration and diffusion of water. In summary, tung oil treatment represents an environmentally friendly and efficient method for maximizing wood recovery and increasing product value. This approach holds significant potential for industrial applications in wood heat treatment.

Keywords: tung oil, heat treatment, physicochemical properties, wood cell walls

Procedia PDF Downloads 55

Authors: Bushra Nabi, Saleha Rehman, Sanjula Baboota, Javed Ali

Abstract:

Aim: The objective of research undertaken is analytical method validation (HPLC method) of an anti-HIV drug Elvitegravir (EVG). Additionally carrying out the forced degradation studies of the drug under different stress conditions to determine its stability. It is envisaged in order to determine the suitable technique for drug estimation, which would be employed in further research. Furthermore, comparative pharmacokinetic profile of the drug from lipid architectonics and drug suspension would be obtained post oral administration. Method: Lipid Architectonics (LA) of EVR was formulated using probe sonication technique and optimized using QbD (Box-Behnken design). For the estimation of drug during further analysis HPLC method has been validation on the parameters (Linearity, Precision, Accuracy, Robustness) and Limit of Detection (LOD) and Limit of Quantification (LOQ) has been determined. Furthermore, HPLC quantification of forced degradation studies was carried out under different stress conditions (acid induced, base induced, oxidative, photolytic and thermal). For pharmacokinetic (PK) study, Albino Wistar rats were used weighing between 200-250g. Different formulations were given per oral route, and blood was collected at designated time intervals. A plasma concentration profile over time was plotted from which the following parameters were determined:

Keywords: AIDS, Elvitegravir, HPLC, nanostructured lipid carriers, pharmacokinetics

Procedia PDF Downloads 126

Authors: Elakneswaran Yogarajah, Toyoharu Nawa, Eiji Owaki

Abstract:

Cement-based materials have been using in various reinforced concrete structural components as well as in nuclear waste repositories. The sulfate attack has been an environmental issue for cement-based materials exposed to sulfate bearing groundwater or soils, and it plays an important role in the durability of concrete structures. The reaction between penetrating sulfate ions and cement hydrates can result in swelling, spalling and cracking of cement matrix in concrete. These processes induce a reduction of mechanical properties and a decrease of service life of an affected structure. It has been identified that the precipitation of secondary sulfate bearing phases such as ettringite, gypsum, and thaumasite can cause the damage. Furthermore, crystallization of soluble salts such as sodium sulfate crystals induces degradation due to formation and phase changes. Crystallization of mirabilite (Na₂SO₄:10H₂O) and thenardite (Na₂SO₄) or their phase changes (mirabilite to thenardite or vice versa) due to temperature or sodium sulfate concentration do not involve any chemical interaction with cement hydrates. Over the past couple of decades, an intensive work has been carried out on sulfate attack in cement-based materials. However, there are several uncertainties still exist regarding the mechanism for the damage of concrete in sulfate environments. In this study, modelling work has been conducted to investigate the chemical degradation of cementitious materials in various sulfate environments. Both internal and external sulfate attack are considered for the simulation. In the internal sulfate attack, hydrate assemblage and pore solution chemistry of co-hydrating Portland cement (PC) and slag mixing with sodium sulfate solution are calculated to determine the degradation of the PC and slag-blended cementitious materials. Pitzer interactions coefficients were used to calculate the activity coefficients of solution chemistry at high ionic strength. The deterioration mechanism of co-hydrating cementitious materials with 25% of Na₂SO₄ by weight is the formation of mirabilite crystals and ettringite. Their formation strongly depends on sodium sulfate concentration and temperature. For the external sulfate attack, the deterioration of various types of cementitious materials under external sulfate ingress is simulated through reactive transport model. The reactive transport model is verified with experimental data in terms of phase assemblage of various cementitious materials with spatial distribution for different sulfate solution. Finally, the reactive transport model is used to predict the long-term performance of cementitious materials exposed to 10% of Na₂SO₄ for 1000 years. The dissolution of cement hydrates and secondary formation of sulfate-bearing products mainly ettringite are the dominant degradation mechanisms, but not the sodium sulfate crystallization.

Keywords: thermodynamic calculations, reactive transport, radioactive waste disposal, PHREEQC

Procedia PDF Downloads 147

Authors: Michael Louis Sunaris, Robby Yussac Tallar

Abstract:

The concept of sustainable river is evolving in Indonesia today. Many rivers condition in Indonesia have decreased by quality and quantity. The degradation of this condition is caused by rapid land use change as a result of increased population growth and human activity. It brings the degradation of the existing watersheds including some types of land use that an important factor in determining the status of river sustainability. Therefore, an evaluation method is required to determine the sustainability status of waterbody within watershed. The purpose of this study is to analyze various types of land use in determining the status of river sustainability. This study takes the watersheds of Citarum Upstream as a study area. The results of the analysis prove the index of sustainability status of the river that changes from good to bad or average in the rivers in the study area. The rapid and uncontrolled changes of land use especially in the upper watersheds area are the main causes that happened over time. It was indicated that the cumulative runoff coefficients were increased significantly. These situations indicated that the damage of watersheds has an impact on the water surplus or deficit problem yearly. Therefore, the rivers in Indonesia should be protected and conserved. The sustainability index of the rivers is an index to indicate the condition of watersheds by defining status of rivers in order to achieve sustainable water resource management.

Keywords: land use change, runoff coefficient, a simple index, sustainable river

Procedia PDF Downloads 136

Authors: Gao Qin, Hu Liwei, Dong Xiangzhou, Zhu Qifa, Cheng Tingming, Zhao Limei, Yang Mengmeng, Zhai Zhen, Dai Huaxin, Liang Taibo, Zhang Shixiang, Xue Chaoqun

Abstract:

The functional strain T976 for starch degradation was isolated from Nicotiana tabacum L. Yunyan 97 tobacco leaves, the ratio of starch hydrolysis transparent circle diameter to colony diameter of the strain was 4.14, 16S rDNA sequencing identified these strains as Enterobacter ludwigii. Then Enterobacter ludwigii T976 was fermented and spaying Yunyan 97 plant in vigorous growing stage. The results of once spraying fermentation broth of Enterobacter ludwigii T976 showed that starch content of upper leaves decreased slightly, from 3.77% to 3.1%, the reducing sugar content increased from 4.39% to 5.53%, and the total sugar content increased from 5.82% to 7.39%. The chemical content was also checked after three time spraying. The starch content of middle leaves decreased from 5.63% to 3.74%, while the content of total sugar and reducing sugar decreased slightly. And the starch content of upper leaves decreased from 7.62% to 4.78%, the total sugar and reducing sugar decreased slightly, and starch content of middle leaf decreased from 6.27% to 3.62%, the total sugar and reducing sugar did not change much, and other chemical components were in a suitable range.

Keywords: nicotiana tabacum, yunyan 97, leaf, starch, degradation, enterobacter ludwigii

Procedia PDF Downloads 32

Authors: Yuvraj S. Malghe, Atul B. Lavand

Abstract:

In recent years, semiconductor photocatalytic degradation processes have attracted a lot of attention and are used widely for the destruction of organic pollutants present in waste water. Among various semiconductors, titanium dioxide (TiO2) is the most popular photocatalyst due to its excellent chemical stability, non-toxicity, relatively low cost and high photo-oxidation power. It has been known that zinc oxide (ZnO) with band gap energy 3.2 eV is a suitable alternative to TiO2 due to its high quantum efficiency, however it corrodes in acidic medium. Unfortunately TiO2 and ZnO both are active only in UV light due to their wide band gaps. Sunlight consist about 5-7% UV light, 46% visible light and 47% infrared radiation. In order to utilize major portion of sunlight (visible spectrum), it is necessary to modify the band gap of TiO2 as well as ZnO. This can be done by several ways such as semiconductor coupling, doping the material with metals/non metals. Doping of TiO2 using transition metals like Fe, Co and non-metals such as N, C or S extends its absorption wavelengths from UV to visible region. In the present work, we have synthesized ZnO-TiO2 nanocomposite using reverse microemulsion method. Visible light photocatalytic activity of synthesized nanocomposite was investigated for degradation of aqueous solution of malachite green (MG). To increase the photocatalytic activity of ZnO-TiO2 nanocomposite, it is decorated with C and Fe. Pure, carbon (C) doped and carbon, iron(C, Fe) co-doped nanosized ZnO-TiO2 nanocomposites were synthesized using reverse microemulsion method. These composites were characterized using, X-ray diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Scanning electron microscopy (SEM), UV visible spectrophotometery and X-ray photoelectron spectroscopy (XPS). Visible light photocatalytic activities of synthesized nanocomposites were investigated for degradation of aqueous malachite green (MG) solution. C, Fe co-doped ZnO-TiO2 nanocomposite exhibit better photocatalytic activity and showed threefold increase in photocatalytic activity. Effect of amount of catalyst, pH and concentration of MG solution on the photodegradation rate is studied. Stability and reusability of photocatalyst is also studied. C, Fe decorated ZnO-TiO2 nanocomposite shows threefold increase in photocatalytic activity.

Keywords: malachite green, nanocomposite, photocatalysis, titanium dioxide, zinc oxide

Procedia PDF Downloads 275

Authors: Nada Verdel, Tomaz Rijavec, Albin Pintar, Ales Lapanje

Abstract:

Objectives: White water circuits of woodfree paper mills contain suspended, dissolved, and colloidal particles, such as cellulose, starch, paper sizings, and dyes. By closing the white water circuits, these particles start to accumulate and affect the production. Due to high amount of organic matter that scavenge radicals and adsorbs onto catalyst surfaces, treatment of white water with photocatalysis is inappropriate. The most suitable approach should be bioaugmentation-assisted bioremediation. Accordingly, objectives were: - to isolate bacteria capable of degrading organic compounds used for the papermaking process - to select the most active bacteria for bioaugmentation. Status: The state-of-the-art of bioaugmentation of pulp and paper mill effluents is mostly based on biodegradation of lignin. Whereas in white water circuits of woodfree paper mills only papermaking compounds are present. As far as one can tell from the literature, the study on degradation activities of bacteria for all possible compounds of the papermaking process is a novelty. Methodology: The main parameters of the selected white water were systematically analyzed during a period of two months. Bacteria were isolated on selective media with particular carbon source. Organic substances used as carbon source either enter white water circuits as base paper or as recycled broke. The screening of bacterial activities for starch, cellulose, latex, polyvinyl alcohol, alkyl ketene dimers, and resin acids was followed by addition of lugol. Degraders of polycyclic aromatic dyes were selected by cometabolism tests; cometabolism is simultaneous biodegradation of two compounds, in which the degradation of the second compound depends on the presence of the first. The obtained strains were identified by 16S rRNA sequencing. Findings: 335 autochthonous strains were isolated on plates with selected carbon source. The isolated strains were selected according to degradation of the particular carbon source. The ultimate degraders of cationic starch, cellulose, and sizings are Pseudomonas sp. NV-CE12-CF and Aeromonas sp. NV-RES19-BTP. The most active strains capable of degrading azo dyes are Aeromonas sp. NV-RES19-BTP and Sphingomonas sp. NV-B14-CF. Klebsiella sp. NV-Y14A-BTP degrade polycyclic aromatic direct blue 15 and also yellow dye, Agromyces sp. NV-RED15A-BF and Cellulosimicrobium sp. NV-A4-BF are specialists for whitener and Aeromonas sp. NV-RES19-BTP is general degrader of all compounds. To the white water adapted bacteria were isolated and selected according to their degradation activities for particular organic substances. Mostly isolated bacteria are specialized to lower the competition in the microbial community. Degraders of readily-biodegradable compounds do not degrade recalcitrant polycyclic aromatic dyes and vice versa. General degraders are rare.

Keywords: bioaugmentation, biodegradation of azo dyes, cometabolism, smart wastewater treatment technologies

Procedia PDF Downloads 187

Authors: Z. Mmango, U. Nwodo, L. V. Mabinya, A. I. Okoh

Abstract:

Cellulose and hemicellulose account for a large portion of the world‘s plant biomass. In nature, these polysaccharides are intertwined forming complex materials that requires multiple and expensive treatment processes to free up the raw materials trapped in the matrix. Enzymatic degradation remains as the preferred technique as it is inexpensive and eco-friendly. However, the insufficiencies of enzyme battery systems in the degradation of lignocellulosic complex motivate the search for effective degrading enzymes from bacterial isolates from uncommon environment. The study aimed at the evaluation of actinomycetes isolated from saw dust samples collected from wood factory under bed. Cellulase and xylanase production was screened through organism culture on carboxyl methyl cellulose agar and Birchwood xylan. Halo zone indicating lignocellose utilization was shown by an isolate identified through 16S rRNA gene as Micrococcus luteus. The optimum condition for the production of cellulase and xylanase were incubation temperature of 25 °C, fermentation medium pH 5 and 10, agitation speed of 50 and 200 (rpm) and fermentation incubation time of 96 and 84 (h) respectively. The high cellulose and xylanase activity obtained from this isolate portends industrial relevance.

Keywords: carboxyl methyl cellulose, birchwood xylan, optimization, cellulase, xylanase, micrococcus, DNS method

Procedia PDF Downloads 331

Authors: Magda Posani, Maria Do Rosario Veiga, Vasco Peixoto De Freitas

Abstract:

The presented research considers the hygrothermal data acquired in the municipal library of Porto. The library is housed in an XVIII century convent and, among all the rooms in the construction, one, in particular, was chosen for the monitoring campaign because of the presence of a great number of historic books. Temperature and relative humidity, as well as CO₂ concentration, were measured for six consecutive months, in the period December 24th - June 24th. The indoor environment of the building is controlled with a heating and cooling system that is turned on only during the opening hours of the library. The ventilation rate is low because the windows are kept closed, and there is no forced ventilation. The micro-climate is analyzed in terms of users’ comfort and degradation risks for historic books and valuable building surfaces. Through a comparison between indoor and outdoor measured hygrothermal data, indoor relative humidity appears very stable. The influence of the hygroscopicity of books on the stabilization of indoor relative humidity is therefore investigated in detail. The paper finally discusses the benefits given by the presence of historic books in libraries with intermittent heating and cooling. The possibility of obtaining a comfortable and stable indoor climate with low use of HVAC systems in these conditions, while avoiding degradation risks for books and historic building components, is further debated.

Keywords: books, historic buildings, hygroscopicity, relative humidity

Procedia PDF Downloads 134

Authors: Muhammad Younis Laghari

Abstract:

Microbial communities play the most important role in aquatic ecosystems. These microbes have a great role in fish growth and aquaculture production. Unfortunately, the farmers are unaware of these useful creatures. Nowadays, the trend of fish farming is developed to re-circulatory aquaculture system (RAS) to increase production and reduce the investment/management cost to increase the profit. However, sometimes, it has been observed that even the growth of fish is decreased in RAS without apparent changes in water quality. There is a great importance of microorganisms in aquaculture, where they occur naturally. However, they can be added artificially by applying different roles. Even these microbes play an important role in the degradation of organic matter and recycling nutrients, along with nutritional support to fish. Even some microorganisms may protect fish and larvae against diseases. But if not managed/utilized properly, they may cause to infect or kill the fish and their larvae. However, manipulating the microbes and monitoring them in aquaculture systems hold great potential to assess and improve the water quality as well as to control the development of microbial infections. While there is an utmost need for research to determine the microbiomes of healthy aquaculture systems, we also need to develop authentic methods for the successful manipulation of microbes as well as engineer these microbiomes. Hence, we should develop a plan to utilize and get full advantage from these microbial interactions for the successful management of aquaculture through advanced research and technology.

Keywords: aquaculture, ecology system, degradation, microbes, nutrient recycling, water quality

Procedia PDF Downloads 62

Authors: Khomkrit Mongkhuntod, Chatchawal Chaichana, Atipoang Nuntaphan

Abstract:

Feed Water Heater is the important equipment for thermal power plant. The heating temperature from feed heating process is an impact to power plant efficiency or heat rate. Normally, the degradation of feed water heater that operated for a long time is effect to decrease plant efficiency or increase plant heat rate. For Mae Moh power plant, each unit operated more than 20 years. The degradation of the main equipment is effect of planting efficiency or heat rate. From the efficiency and heat rate analysis, Mae Moh power plant operated in high heat rate more than the commissioning period. Some of the equipment were replaced for improving plant efficiency and plant heat rates such as HP turbine and LP turbine that the result is increased plant efficiency by 5% and decrease plant heat rate by 1%. For the target of power generation plan that Mae Moh power plant must be operated more than 10 years. These work is focus on thermal efficiency analysis of feed water heater to compare with the commissioning data for find the way to improve the feed water heater efficiency that may effect to increase plant efficiency or decrease plant heat rate by use heat balance model simulation and economic value add (EVA) method to study the investment for replacing the new feed water heater and analyze how this project can stay above the break-even point to make the project decision.

Keywords: feed water heater, power plant efficiency, plant heat rate, thermal efficiency analysis

Procedia PDF Downloads 348

Authors: Madhumita Roy

Abstract:

Kolkata, the city of joy, is an organic city with 45 lakhs of people till date. The increasing population stress is creating a constant pressure on the ground surface which in turn reducing the possible area for plantation. Humans, plants, and birds have a mutualistic relationship, and all are dependent on each other for their survival. Vegetation structure is very important for a bird life because it can be used as a residence, foraging, life cycle, and shelter from predators. On the other hand, in urban areas, buildings and structures also plays a major role for birds habitat w.r.t, nesting, resting, etc. City birds are constantly upgrading their adaptative mechanism with changing urban pattern with modern architectural designs. Urbanisation and unplanned development lead to environmental degradation and bird habitat fragmentation, which have impacts on the degradation of the quality and quantity of bird habitat. Declining green cover and habitat loss affects the diversity and population structure of birds. Their reducing number is an increasing threat not only to the bird community but also to the city as birds are considered as one of the most important environmental indicator. This study aims to check the present avian status like species richness, relative abundance, and diversity of bird species in the context of changing urban pattern in Kolkata city. Nesting strategy in the urban habitat of the avian community is another avenue of interest.

Keywords: urbanisation, avian species, kolkata metropolis, planning

Procedia PDF Downloads 87

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

Abstract:

The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester non-woven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibers. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

Procedia PDF Downloads 303

Authors: Orkan Ozcan, Nebiye Musaoglu, Murat Turkes

Abstract:

Climate change is largely recognized as one of the real, pressing and significant global problems. The concept of ‘climate change vulnerability’ helps us to better comprehend the cause/effect relationships behind climate change and its impact on human societies, socioeconomic sectors, physiographical and ecological systems. In this study, multifactorial spatial modeling was applied to evaluate the vulnerability of a Mediterranean forest ecosystem to climate change. As a result, the geographical distribution of the final Environmental Vulnerability Areas (EVAs) of the forest ecosystem is based on the estimated final Environmental Vulnerability Index (EVI) values. This revealed that at current levels of environmental degradation, physical, geographical, policy enforcement and socioeconomic conditions, the area with a ‘very low’ vulnerability degree covered mainly the town, its surrounding settlements and the agricultural lands found mainly over the low and flat travertine plateau and the plains at the east and southeast of the district. The spatial magnitude of the EVAs over the forest ecosystem under the current environmental degradation was also determined. This revealed that the EVAs classed as ‘very low’ account for 21% of the total area of the forest ecosystem, those classed as ‘low’ account for 36%, those classed as ‘medium’ account for 20%, and those classed as ‘high’ account for 24%. Based on regionally averaged future climate assessments and projected future climate indicators, both the study site and the western Mediterranean sub-region of Turkey will probably become associated with a drier, hotter, more continental and more water-deficient climate. This analysis holds true for all future scenarios, with the exception of RCP4.5 for the period from 2015 to 2030. However, the present dry-sub humid climate dominating this sub-region and the study area shows a potential for change towards more dry climatology and for it to become a semiarid climate in the period between 2031 and 2050 according to the RCP8.5 high emission scenario. All the observed and estimated results and assessments summarized in the study show clearly that the densest forest ecosystem in the southern part of the study site, which is characterized by mainly Mediterranean coniferous and some mixed forest and the maquis vegetation, will very likely be influenced by medium and high degrees of vulnerability to future environmental degradation, climate change and variability.

Keywords: forest ecosystem, Mediterranean climate, RCP scenarios, vulnerability analysis

Procedia PDF Downloads 338

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

Abstract:

The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester nonwoven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibres. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

Procedia PDF Downloads 333

Authors: J. S. Rudas, J. M. Gutiérrez Cabeza, A. Corz Rodríguez, L. M. Gómez, A. O. Toro

Abstract:

The prediction of the wear rate of rubbing pairs has attracted the interest of many researchers for years. It has been recently proposed that the sliding wear rate can be inferred from the calculation of the energy rate dissipated by the tribological pair. In this paper some of the dissipative mechanisms present in a pin-on-disc configuration are discussed and both analytical and numerical calculations are carried out. Three dissipative mechanisms were studied: First, the energy release due to temperature gradients within the solid; second, the heat flow from the solid to the environment, and third, the energy loss due to abrasive damage of the surface. The Finite Element Method was used to calculate the dynamics of heat transfer within the solid, with the aid of commercial software. Validation the FEM model was assisted by virtual and laboratory experimentation using different operating points (sliding velocity and geometry contact). The materials for the experiments were Ti6Al4V alloy and Tungsten Carbide (WC-Co). The results showed that the sliding wear rate has a linear relationship with the energy dissipation flow. It was also found that energy loss due to micro-cutting is relevant for the system. This mechanism changes if the sliding velocity and pin geometry are modified though the degradation coefficient continues to present a linear behavior. We found that the less relevant dissipation mechanism for all the cases studied is the energy release by temperature gradients in the solid.

Keywords: degradation, dissipative mechanism, dry sliding, entropy, friction, wear

Procedia PDF Downloads 490

Authors: L. Alejandro Cárdenas, Fernando Herrera, David Nova, Juan Ballesteros

Abstract:

This paper presents a methodology to optimize the maintenance of grid-connected photovoltaic systems, considering the cleaning and module replacement periods based on an asset management strategy. The methodology is based on the analysis of the energy production of the PV plant, the energy feed-in tariff, and the cost of cleaning and replacement of the PV modules, with the overall revenue received being the optimization variable. The methodology is evaluated as a case study of a 5.6 kWp solar PV plant located on the Bogotá campus of the Universidad Nacional de Colombia. The asset management strategy implemented consists of assessing the PV modules through visual inspection, energy performance analysis, pollution, and degradation. Within the visual inspection of the plant, the general condition of the modules and the structure is assessed, identifying dust deposition, visible fractures, and water accumulation on the bottom. The energy performance analysis is performed with the energy production reported by the monitoring systems and compared with the values estimated in the simulation. The pollution analysis is performed using the soiling rate due to dust accumulation, which can be modelled by a black box with an exponential function dependent on historical pollution values. The pollution rate is calculated with data collected from the energy generated during two years in a photovoltaic plant on the campus of the National University of Colombia. Additionally, the alternative of assessing the temperature degradation of the PV modules is evaluated by estimating the cell temperature with parameters such as ambient temperature and wind speed. The medium-term energy decrease of the PV modules is assessed with the asset management strategy by calculating the health index to determine the replacement period of the modules due to degradation. This study proposes a tool for decision making related to the maintenance of photovoltaic systems. The above, projecting the increase in the installation of solar photovoltaic systems in power systems associated with the commitments made in the Paris Agreement for the reduction of CO2 emissions. In the Colombian context, it is estimated that by 2030, 12% of the installed power capacity will be solar PV.

Keywords: asset management, PV module, optimization, maintenance

Procedia PDF Downloads 22

Authors: Muhammad Ajmal, Muhammad Siddiq, Nurettin Sahiner

Abstract:

We prepared poly(methacrylic acid-co-acrylonitrile) (p(MAc-co-AN)) microgels by inverse suspension polymerization, and converted the nitrile groups into amidoxime groups to obtain more hydrophilic amidoximated poly(methacrylic acid-co-acrylonitile) (amid-p(MAc-co-AN)) microgels. Amid-microgels were used as microreactors for in situ synthesis of copper and cobalt nanoparticles. Cu (II) and Co (II) ions were loaded into microgels from their aqueous metal salt solutions and then converted to corresponding metal nanoparticle (MNP) by treating the loaded metal ions with sodium borohydride (NaBH4). The characterization of the prepared microgels and microgel metal nanoparticle composites was carried out by SEM, TEM and TG analysis. The amounts of metal nanoparticles within microgels were estimated by AAS measurements by dissolving the MNP entrapped within microgels by concentrated HCl acid treatment. Catalytic performances of the prepared amid-p(MAc-co-AN)-M (M: Cu, Co) microgel composites were investigated by using them as catalyst for the degradation of cationic and anionic organic dyes such as eosin Y (EY), methylene blue (MB) and methyl Orange (MO), and for the reduction of nitro aromatic pollutants like 2-nitrophenol (2-NP) and 4-nitrophenol (4-NP) to their corresponding amino phenols. Here, we also report for the first time, the simultaneous degradation/reduction of MB, EY, and 4-NP by amid-p(MAc-co-AN)-Cu microgel composites. Different parameters affecting the reduction rates such as metal types, amount of catalysts, temperature and the amount of reducing agent were investigated.

Keywords: microgels, nanoparticles, catalyst, pollutants

Procedia PDF Downloads 337

Authors: Sourour Chaabane, Davide Clematis, Marco Panizza

Abstract:

This study investigates the oxidation of Erythrosine B (EB) food dye by a homogeneous electro-Fenton process using iron (II) sulfate heptahydrate as a catalyst, carbon felt as cathode, and Ti/RuO2. The treated synthetic wastewater contains 100 mg L⁻¹ of EB and has a pH = 3. The effects of three independent variables have been considered for process optimization, such as applied current intensity (0.1 – 0.5 A), iron concentration (1 – 10 mM), and stirring rate (100 – 1000 rpm). Their interactions were investigated considering response surface methodology (RSM) based on Doehlert design as optimization method. EB removal efficiency and energy consumption were considered model responses after 30 minutes of electrolysis. Analysis of variance (ANOVA) revealed that the quadratic model was adequately fitted to the experimental data with R² (0.9819), adj-R² (0.9276) and low Fisher probability (< 0.0181) for EB removal model, and R² (0.9968), adj-R² (0.9872) and low Fisher probability (< 0.0014) relative to the energy consumption model reflected a robust statistical significance. The energy consumption model significantly depends on current density, as expected. The foregoing results obtained by RSM led to the following optimal conditions for EB degradation: current intensity of 0.2 A, iron concentration of 9.397 mM, and stirring rate of 500 rpm, which gave a maximum decolorization rate of 98.15 % with a minimum energy consumption of 0.74 kWh m⁻³ at 30 min of electrolysis.

Keywords: electrofenton, erythrosineb, dye, response serface methdology, carbon felt

Procedia PDF Downloads 59

Authors: Diana Bardhi

Abstract:

Road safety is an essential part of the economic and social development of any industrialized country. Decisions to maintain and improve the reliability, functionality of infrastructure structures can only be achieved through integrated road life cycle planning and management. There has always been a tendency to review road maintenance strategies, but there is still no serious and reliable administration due to not only insufficient funds but also problems in the proper reorganization of this system. The safety and performance of the road system depend on the ongoing activity of road maintenance management. For it to be effective, it is necessary to intervene before the degradation has caused irreparable damage or damage with a high economic cost of repairs. Investments in road infrastructure during 2006-2014 show that the life of these projects presents problems related to the maintenance and management of life cycle performance in a wide range of constituent elements. Maintenance planning includes various problems that depend on the degree of degradation of asphalt layers, the degree of damage to road structures (bridges, tunnels, culverts, and the economic planning of resources for their repair). The purpose of this study is first to provide a brief overview of the problems in the field of maintenance and life cycle management of road infrastructure investments, proposing ways to reorganize the sector of administration and maintenance of ongoing roads and secondly testing and evaluating the work and nature of standards of different types of road infrastructure projects, through a methodology consisting of a) development, b) data collection, and c) analysis.

Keywords: infrastructure, maintenance, depreciation, efficiency

Procedia PDF Downloads 139

Authors: Cherry Dhiman, Ayushi Paliwal, Mohd. Shahid Khan, M. N. Reddy, Vinay Gupta, Monika Tomar

Abstract:

The laser based high resolution spectroscopic experimental techniques such as Laser Induced Breakdown Spectroscopy (LIBS), Rotating Disk Electrode Optical Emission spectroscopy (RDE-OES) and Surface Plasmon Resonance (SPR) have been used for the study of composition and degradation analysis of used engine oils. Engine oils are mainly composed of aliphatic and aromatics compounds and its soot contains hazardous components in the form of fine, coarse and ultrafine particles consisting of wear metal elements. Such coarse particulates matter (PM) and toxic elements are extremely dangerous for human health that can cause respiratory and genetic disorder in humans. The combustible soot from thermal power plants, industry, aircrafts, ships and vehicles can lead to the environmental and climate destabilization. It contributes towards global pollution for land, water, air and global warming for environment. The detection of such toxicants in the form of elemental analysis is a very serious issue for the waste material management of various organic, inorganic hydrocarbons and radioactive waste elements. In view of such important points, the current study on used engine oils was performed. The fundamental characterization of engine oils was conducted by measuring water content and kinematic viscosity test that proves the crude analysis of the degradation of used engine oils samples. The microscopic quantitative and qualitative analysis was presented by RDE-OES technique which confirms the presence of elemental impurities of Pb, Al, Cu, Si, Fe, Cr, Na and Ba lines for used waste engine oil samples in few ppm. The presence of such elemental impurities was confirmed by LIBS spectral analysis at various transition levels of atomic line. The recorded transition line of Pb confirms the maximum degradation which was found in used engine oil sample no. 3 and 4. Apart from the basic tests, the calculations for dielectric constants and refractive index of the engine oils were performed via SPR analysis.

Keywords: surface plasmon resonance, laser-induced breakdown spectroscopy, ICCD spectrometer, engine oil

Procedia PDF Downloads 130

Authors: Şevket Evci, Mehmet Akif Karsli

Abstract:

The aim of this study is to determine nutrient contents, in situ ruminal degradation kinetics and protein fractions of screenings bean (B), chick pea (ChP), red lentil (RL) and green lentil (GL) that is used as residue in grain legume packing industry. For this purpose, four samples of each legumes species-a total of 16 samples, collected from different parts of our country were utilized. Feedstuffs used in the experiment were incubated for 0, 2 4, 8, 12, 24, and 48 hours in the rumen of 3 ruminally cannulated Akkaraman rams as duplicate. The nutrient contents, in situ ruminal dry matter (DM), organic matter (OM) and crude protein (CP) degradabilities and fractions, and escape protein contents were evaluated. The highest OM and CP contents were observed in RL (P<0.05). Chick pea had the highest ether extract (EE) content and EE values were 3.47, 6.72, 2.26, 8.66 % for RL, B, GL and ChP, respectively (P<0.05). Crude fiber (CF), ADF, and NDF contents were the highest in RL and the lowest in ChP. CF values were 24.03, 10.80, 4.09 and 3.57 % for RL, GL, B and ChP (P<0.05). Acid detergent insoluble nitrogen content of samples did not differ. Escape protein content was the highest in RL and the lowest in B (P<0.05). After 48 h incubation, the lowest OM and CP degradabilities were observed in RL. While the highest OM degradability was seen in ChP the highest CP degradability was observed in B (P<0.05). The lowest water soluble OM and CP contents were observed in RL whereas the highest potentially degradable OM and CP contents were seen in B and ChP (P<0.05). Both rate of OM and CP degradations (k-1) did not differ among samples (P>0.05). In conclusion, it was noted that feedstuffs (GL, ChP and B) used in the experiment except RL had a greater ruminal degradibilities of both OM and CP and moreover, had a higher escape protein contents, except B. It was thought that these feedstuffs can be substituted with some of common protein sources used in animal nutrition.

Keywords: in situ, nutrient contents, ruminant, subsieve

Procedia PDF Downloads 465

Authors: Suchitra Sivakumar, Hajime Shingyouchi, Toshinori Okajima, Kyohei Yamaguchi, Jin Kusaka

Abstract:

The progressing need for powertrain electrification calls for more accurate and reliable simulation models. A battery pack serves as the most vital component for energy storage in an electrified powertrain. Hybrid electric vehicles (HEV) do not behave the same way as they age, and there are several environmental factors that account for the degradation of the battery on a system level. Therefore, in this work, a battery model was proposed to study the state of charge (SOC) variation and the internal dynamic changes that contribute to aging and performance degradation in HEV batteries. An equivalent circuit battery model (ECM) is built using MATLAB Simulink to investigate the output characteristics of the lithium-ion battery. The ECM comprises of circuit elements like a voltage source, a series resistor and a parallel RC network connected in series. A parameter estimation study is conducted on the ECM to study the dependencies of the circuit elements with the state of charge (SOC) and the terminal voltage of the battery. The battery model is extended to simulate the temperature dependence of the individual battery cell and the battery pack with the environment. The temperature dependence model accounts for the heat loss due to internal resistance build up in the battery pack during charging, discharging, and due to atmospheric temperature. The model was validated for a lithium-ion battery pack with an independent drive cycle showing a voltage accuracy of 4% and SOC accuracy of about 2%.

Keywords: battery model, hybrid electric vehicle, lithium-ion battery, thermal model

Procedia PDF Downloads 276