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Waste Generation and Characteristics in Sri Lankan Textile and Apparel Sector: Case Study of the Biyagama Industrial Export Processing Zone, Sri Lanka
2022
L.G.L.M. Edirisinghe, M. Wijayasundara | A.A.P. De Alwis
The main goal of the study was to look at the properties of waste, treatment options, and disposal techniques. Furthermore, waste circulation variables in the textile and apparel sectors in Sri Lanka’s Biyagama Industrial Processing Zone were calculated. The types, volumes, and per capita waste generation of ten industries were analyzed, as well as waste management activities such as trash minimization, handling, storing, recirculation, and disposal. The information was gathered using questionnaires, interviews, and field observations. According to the findings, the total industrial waste generation rate was 13792.5 tonnes per year, with 5926 tonnes per year designated as hazardous waste materials (42.9%). Furthermore, the waste generation rate per capita was 0.93 kg. The waste circulation factor was 0.38, according to the findings. The findings of the study highlight the necessity for integrated waste management methods in the textile and apparel industries.
Mostrar más [+] Menos [-]The Drawing Characteristics and Critical Length of Single Polypropylene Fiber in Vegetation Concrete
2022
Daxiang Liu, Deyu Liu, Baohua Zhang, Bin Zhong, Yueshu Yang, Jiangang Chen, Yu Ding, Zhenyao Xia | Wennian Xu
Fiber-reinforced technology is an important method to improve the stability and durability of growing basis material. To evaluate the factors affecting the interfacial strength properties of polypropylene fiber reinforced vegetation concrete, single polypropylene fiber drawing tests were conducted by using a modified apparatus. The mechanical interaction behavior between vegetation concrete and polypropylene fiber was discussed by using a polarizing microscope. The results indicate that the drawing curves between polypropylene fiber and vegetation concrete show a typical multi-peak characteristic. And the interfacial shear strength is the minimum at the optimum water content (20%) in the 1d sample. It should be noted that both interfacial peak strength (IPS) and interfacial residual strength (IRS) increase with the increase of dry density and curing time for vegetation concrete. Then through multiple linear regression analysis, the empirical formula of critical fiber length in reinforced vegetation concrete is obtained, which can improve the engineering durability of vegetation concrete in harsh conditions.
Mostrar más [+] Menos [-]Treatment of Saline Water Using Electrocoagulation Process with Monopolar Connection of Electrodes
2022
Isra’a Sadi Samaka, Ahmed Samir Naje | Hussein A. M. Al-Zubaidi
For the availability of drinking water, saline water treatment has become exceedingly necessary. The purpose of this research was to determine how efficient electrocoagulation (EC) with monopolar iron electrodes was for desalinating water from Iraq’s Sawa Lake. Absolute dissolved solids (TDS), chloride (Cl), bromine (Br), and sulfate (SO4) are some of the salty water forms that are being targeted. The impacts of five considerations on treatment efficiency were studied, including current (I), detention time (RT), pH, speed of mixing stirring (Mrpm), and inter-electrode distance (IED). I=0.8A, RT=80 minutes, pH=8, IED=1cm, and Mrpm=500 were found to be the best values. TDS, Cl, Br and SO4 removal efficiencies were 91 percent, 93 percent, 92 percent, and 90 percent, respectively, under ideal conditions. It can be inferred that the EC system used in this research was operative in removing salts from the water of Sawa lake.
Mostrar más [+] Menos [-]Effects of Chelating Surfactants on Competitive Adsorption of Lead and Zinc on Loess Soil
2022
H. T. Qiao, B. W. Zhao | X. S. Yu
The study of competitive adsorption of heavy metals on soil is important for heavy metals contaminated soil remediation. However, there have been few studies on the impact of desorption reagents on heavy metal adsorption in soil. Batch adsorption studies were used to investigate the competitive adsorption mechanism of two heavy metals, Pb and Zn, on a loess soil in the presence of a new chelating surfactant, sodium N-lauroyl ethylenediamine triacetate (LED3A). Results showed that competitive adsorption equilibria of Pb and Zn were reached at 3 and 10 h, respectively. The maximum equilibrium adsorption capacities were 19.55 and 18.35 g.kg-1, respectively. LED3A affected the competitive adsorption kinetics of Pb and Zn by increasing the change in external mass transfer and reducing the change in internal mass transfer. LED3A reduced Pb and Zn adsorption capacities onto the soil through competitive chelation of the heavy metals. The heavy metal chelating ability of LED3A was higher for Zn than for Pb. When its concentration was larger than 5 g.L-1, LED3A showed a significant effect on the competitive adsorption of Pb and Zn. In the competitive system, the effect of Pb concentration on the Zn adsorption capacity was greater than the effect of Zn concentration on the Pb adsorption capacity. LED3A weakened the effect of Pb concentration and enhanced the effect of Zn concentration. LED3A showed a significant potential for efficiently leaching remediation of Pb and Zn co-contaminated soil.
Mostrar más [+] Menos [-]Environmental Changes in a Mediterranean River (Upper Sebou, Morocco) Between 1981 and 2017
2022
Mariam Zerrouk, Mohamed Dakki, Mohammed Aziz El Agbani | Oumnia Himmi
The functioning and sustainability of lotic ecosystems depend to a large extent on their thermal and hydrological regimes. In the Mediterranean region, these factors are very sensitive to climate and anthropization which have undergone deep changes over the last four decades. Having noted the drying up of many permanent streams in Morocco, we conducted in 2015-2017 a new study with the aim of analyzing and assessing abiotic changes in the Upper Sebou (Middle Atlas, Morocco). A former study was carried out in 1981-1985. Indeed, over the last four decades, this river has been exposed to multiple disturbances, due to both recurrent droughts and human pressures. To describe and assess these changes, we used 16 abiotic variables that were measured in 11 ecosystems along the central course of the river. The comparison was mainly carried out using the multiple factorial correspondence analysis (MFCA), through a ternary matrix “variables × stations × time”, gathering old and new data in the same mesological structure. The analysis revealed the classical upstream-downstream ordering of the studied ecosystems, where most of the ecosystems recorded a downstream migration from their 1981 position. In this evolutionary perspective, the study involves hydrological and thermal factors, which show mainly a reduction in flow and a slight increase in temperature and water mineralization, both in summer and winter. It is assumed that water withdrawals, especially for irrigation, together with climatic droughts in the region, are responsible for these long-term evolutionary trends.
Mostrar más [+] Menos [-]Analysis of Carbon Emission and Its Temporal and Spatial Distribution in County-Level: A Case Study of Henan Province, China
2022
Sen Li, Yanwen Lan | Lijun Guo
Estimating carbon emissions and assessing their contribution are critical steps toward China’sobjective of reaching a “carbon peak” in 2030 and “carbon neutrality” in 2060. This paper selectsrelevant statistical data on carbon emissions from 2000 to 2018, combines the emission coefficientmethod and the Logarithmic Mean Divisia Index model (LMDI) to calculate carbon emissions, andanalyses the driving force of carbon emission growth using Henan Province as a case study. Based onthe partial least squares regression analysis model (PLS), the contributions of inter-provincial factorsof carbon emission are analyzed. Finally, a county-level downscaling estimation model of carbonemission is further formulated to analyze the temporal and spatial distribution of carbon emissions andtheir evolution. The research results show that: 1) The effect of energy intensity is responsible for 82percent of the increase in carbon emissions, whereas the effect of industrial structure is responsiblefor -8 percent of the increase in carbon emissions. 2) The proportion of secondary industry and energyintensity, which are 1.64 and 0.82, respectively, have the most evident explanatory effect on total carbonemissions; 3). Carbon emissions vary widely among counties, with high emissions in the central andnorthern regions and low emissions in the southern. However, their carbon emissions have constantlydecreased over time. 4) The number of high-emission counties, their carbon emissions, and the degreeof their discrepancies are gradually reduced. The findings serve as a foundation for relevant agenciesto gain a macro-level understanding of the industrial landscape and to investigate the feasibility ofcarbon emission reduction programs.
Mostrar más [+] Menos [-]Use of Recycled Construction and Demolition (C&D) Wastes in Soil Stabilization
2022
S. P. Sangeetha, Zhimoholi T. Chophi, Pooja Venkatesh | Muhammad Fahad
With the growing construction sector, there is a constant rise in wastes generated by both construction and demolition activities. According to an estimate by Building Material Promotion Council (BMPTC), 150 million tonnes of construction and demolition (C&D) wastes are generated in India annually. However, the official recycling capacity is a meagre6, 500 tonnes per day (TPD) - just about 1 percent. This paper examines the properties of Black cotton soil and investigates the use of recycled C&D wastes in soil stabilization of black cotton soil. This research focuses on the inexpensive and eco-friendly nature of C&D wastes as an admixture for soil stabilization. The tests were performed using different proportions of recycled C&D wastes in the proportions: 5%, 10%, 15%, 20%, and 25%, to increase the strength of black cotton soil. California Bearing Ratio (CBR) showed an increase from 2% to 18.09%, Maximum Dry Density (MDD) showed a decrease from 2.107 g.cc-1 to 1.69 g.cc-1, and Optimum Moisture Content (OMC) showed a variation and increased from 15% to 18.09% with the addition of 25% C&D wastes.
Mostrar más [+] Menos [-]Check List of Species Richness and Abundance of Orthoptera Fauna in Bharathi Park, Coimbatore, Tamil Nadu, India
2022
M. Suganya | K. Manimegalai
Order Orthoptera is one of the largest and most important invertebrate groups for environmental monitoring and assessment. Orthoptera faunal composition was carried out at Bharathi Park, Coimbatore, Tamil Nadu, India to evaluate the present status of various species. PAST software was used to perform various statistical analyses to estimate the Orthoptera composition. Overall, 334 individuals belonging to 22 species, 19 genera, 17 tribes under 10 subfamilies, and four families of Orthoptera were recorded. Species richness (59.09%) and species abundance (70.06%) were recorded highest in the Acrididae family followed by Pyrgomorphidae, Tettigoniidae, and Gryllidae. Oedipodinae was the most species-rich (27.27%) and the most abundant subfamily, accounting for 30.24% of the total collected individuals. During the study period, 10 dominant, five intermediate dominance, four incidental, and three rare species were observed. Among these, Spathosternum prasiniferum was found to be the most dominant species (D=18.26) and the least dominant (D = 0.6) species was Euconocephalus pallidus. Based on the principal component analysis, the distribution of species along with the first two PCs (PC1= 33.87% and PC2=28.68%) accounted for the highest variance of the total variances. Cluster analysis showed that Acrotylus humbertianus and Teleogryllus mitratus, Conocephalus maculates and Gryllus bimaculatus Orthopterans were similar to each other. The value of the Shannon diversity index (2.27), Simpson index (0.87), Margalef index (2.2), and α-diversity (5.75) were higher in Acrididae when compared with other families. Value of Evenness (0.93) was highest in Gryllidae. Statistical analysis infers that the richness and abundance percentage of Orthopterans significantly varied between species to species and family to family.
Mostrar más [+] Menos [-]Time-series incubations in a coastal environment illuminates the importance of early colonizers and the complexity of bacterial biofilm dynamics on marine plastics
2022
Lemonnier, C. | Chalopin, Morgane | Huvet, Arnaud | Le Roux, Frederique | Labreuche, Yannick | Petton, Bruno | Maignien, Lois | Paul-pont, Ika | Reveillaud, J.
The problematic of microplastics pollution in the marine environment is tightly linked to their colonization by a wide diversity of microorganisms, the so-called plastisphere. The composition of the plastisphere relies on a complex combination of multiple factors including the surrounding environment, the time of incubation along with the polymer type, making it difficult to understand how the biofilm evolves during the microplastic lifetime over the oceans. To better define bacterial community assembly processes on plastics, we performed a 5 months spatio-temporal survey of the plastisphere in an oyster farming area in the Bay of Brest (France). We deployed three types of plastic pellets in two positions in the foreshore and in the water column. Plastic-associated biofilm composition in all these conditions was monitored using 16 S rRNA metabarcoding and compared to free-living and attached bacterial members of seawater. We observed that bacterial families associated to plastic pellets were significantly distinct from the ones found in seawater, with a significant prevalence of filamentous Cyanobacteria on plastics. No convergence towards a unique plastisphere was detected between polymers exposed in the intertidal and subtidal area, emphasizing the central role of the surrounding environment on constantly shaping the plastisphere community diversity. However, we could define a bulk of early-colonizers of marine biofilms such as Alteromonas, Pseudoalteromonas or Vibrio. These early-colonizers could reach high abundances in floating microplastics collected in field-sampling studies, suggesting the plastic-associated biofilms could remain at early development stages across large oceanic scales. Our study raises the hypothesis that most members of the plastisphere, including putative pathogens, could result of opportunistic colonization processes and unlikely long-term transport.
Mostrar más [+] Menos [-]Dyes Biodegradation in the Presence of Hexavalent Chromium by Streptomyces sp. KY75: a Novel Heavy Metal Resistant Strain Isolated in Algeria
2022
Tighidet, Salima | Plewniak, Frédéric | Sayeh, Amalia | Gil, Lisa | Vandecasteele, Céline | Lopez-Roques, Céline | Kecha, Mouloud | Bertin, Philippe | Génome et Transcriptome - Plateforme Génomique ( GeT-PlaGe) ; Plateforme Génome & Transcriptome (GET) ; Génopole Toulouse Midi-Pyrénées [Auzeville] (GENOTOUL) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Génopole Toulouse Midi-Pyrénées [Auzeville] (GENOTOUL) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | A novel heavy metal resistant actinobacterial strain was isolated from an old lead and zinc mine in north-eastern Algeria. This strain was shown to resist high concentrations of heavy metals, including up to 500 ppm arsenic, 700 ppm cadmium, 1750 ppm chromium, 1250 ppm cobalt, 1000 ppm copper, 2750 ppm iron, 2750 ppm lead, 800 ppm mercury, 1750 ppm nickel, and 2750 ppm zinc. In addition, it was able to degrade dyes of the most used families, i.e., triphenylmethane (Malachite Green), azo (Ponceau S), and anthraquinone (Remazol Brilliant Blue R) dyes at 97.79%, 62.93%, and 39.41%, respectively. This bacterium was identified by sequencing the 16S rRNA encoding gene and affiliated to the genus Streptomyces by the RDP Naive Bayesian rDNA Classifier Version 2.11. The genome of Streptomyces sp. KY75 was sequenced using Illumina MiSeq and Oxford Nanopore. It was annotated by the MicroScope platform, and gene codings for resistance to heavy metals and dye biodecolorization were identified. It has a single linear chromosome with 7,837,660 bp and a GC content of 71.58%, 7509 of coding sequences (CDS), 66 tRNA genes, 18 rRNA genes, and 11 pseudogenes. The effect of hexavalent chromium on the dye biodegradation in liquid medium was also tested. Surprisingly, the dye biodegradation was not affected by the addition of hexavalent chromium. These observations make the actinobacterial strain Streptomyces sp. KY75 a good candidate for the bioremediation of textile dyeing industry effluents.
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