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Techno-Economic Assessment of Removing BTEX Pollutants by Designing Thermal Oxidation Unit in a Bituminous Waterproofing Factory in Iran
2023
Soltanianzadeh, Zahra | Mirmohammadi, Mohsen | Zahed, Mohammad ali
Chemical degradation-based methods including oxidation have shown great promise for controlling benzene, toluene, ethylbenzeneandxylene isomers (BTEX) in waste gas. This study presents an approach in which the emission of BTEX compounds in a bituminous waterproofing (BW) production unit located in the city of Delijan, Iran has been controlled through process modification. The process is modified by introducing a thermal oxidation unit using an incinerator design. The process simulation has been performed with Aspen Hysys software and, key parameters in the oxidation process are identifiedandoptimized. Finally, the environmentalandeconomic performances of the incinerator were assessed to provide a decision support tool for the selection of this approach. Finally, the environmentalandeconomic performances of the incinerator have been assessed to provide a decision support tool for the selection of this approach. The results indicated that the formation of the oxidation unit had prevented the release of BTEX pollutants up to 98.5%. Moreover, the economic analysis illustrated that the rate of return on investment in the proposed project is 0.27. Thus, the potential for attracting capital will have positive impacts on the environmentalandeconomic indicators of the region.
Показать больше [+] Меньше [-]Phthalates and attributable mortality: A population-based longitudinal cohort study and cost analysis
2022
Trasande, Leonardo | Liu, Buyun | Bao, Wei
Accelerating evidence of endocrine-related morbidity has raised alarm about the ubiquitous use of phthalates in the human environment, but studies have not directly evaluated mortality in relation to these exposures. To evaluate associations of phthalate exposure with mortality, and quantify attributable mortality and lost economic productivity in 2013–4 among 55–64 year olds. This nationally representative cohort study included 5303 adults aged 20 years or older who participated in the US National Health and Nutrition Examination Survey 2001–2010 and provided urine samples for phthalate metabolite measurements. Participants were linked to mortality data from survey date through December 31, 2015. Data analyses were conducted in July 2020. Mortality from all causes, cardiovascular disease, and cancer. Multivariable models identified increased mortality in relation to high-molecular weight (HMW) phthalate metabolites, especially those of di-2-ethylhexylphthalate (DEHP). Hazard ratios (HR) for continuous HMW and DEHP metabolites were 1.14 (95% CI 1.06–1.23) and 1.10 (95% CI 1.03–1.19), respectively, with consistently higher mortality in the third tertile (1.48, 95% CI 1.19–1.86; and 1.42, 95% CI 1.13–1.78). Cardiovascular mortality was significantly increased in relation to a prominent DEHP metabolite, mono-(2-ethyl-5-oxohexyl)phthalate. Extrapolating to the population of 55–64 year old Americans, we identified 90,761–107,283 attributable deaths and $39.9–47.1 billion in lost economic productivity. In a nationally representative sample, phthalate exposures were associated with all-cause and cardiovascular mortality, with societal costs approximating $39 billion/year or more. While further studies are needed to corroborate observations and identify mechanisms, regulatory action is urgently needed.
Показать больше [+] Меньше [-]Three-year field experiment on the risk reduction, environmental merit, and cost assessment of four in situ remediation technologies for metal(loid)-contaminated agricultural soil
2020
Wan, Xiaoming | Lei, Mei | Yang, Jun | Chen, Tongbin
The traditional assessment of agricultural soil remediation technologies pay limited attention to sustainability and only considers the decrease in contaminant concentrations and cost, even though the sustainability of these technologies has been prioritized. This 3-year field study comprehensively assessed the sustainability of four commonly used agricultural soil remediation technologies in terms of metal(loid) removal efficiency, environmental merit, and cost. The farmland was contaminated by previous sewage irrigation with excessive amounts of As, Cd, and Pb. The four selected remediation technologies used were phytoextraction, intercropping of hyperaccumulators and cash crops, chemical immobilization, and turnover and attenuation (T&A). A risk reduction–environmental merit–cost model was utilized to compare these four technologies. Results showed that T&A reduced the health risks posed by excess metal(loid)s by ∼47% and yielded the highest risk reduction and lowest cost. Phytoextraction achieved the highest environmental merit because it produced the least interruption to the environment. A simplified assessment frame for soil remediation technology was established from a retrospective aspect using data from a real soil remediation project. Environmental merit is a less considered factor and more difficult to quantify than risk reduction or cost, thus requiring increased attention.
Показать больше [+] Меньше [-]Removal of Toxic Elements and Microbial Contaminants from Groundwater Using Low-Cost Treatment Options
2021
Da’ana, Dana A. | Zouari, Nabil | Ashfaq, Mohammad Y. | Abu-Dieyeh, Mohammed | Khraisheh, Majeda | Hijji, Yousef M. | Al-Ghouti, Mohammad A.
PURPOSE OF REVIEW: This paper reviews various low-cost treatment techniques such as adsorption, permeable reactive barrier, and biological techniques for the simultaneous removal of chemical and microbial contaminants from groundwater and discusses treatment mechanisms of different treatment techniques. This paper also discusses the challenges of groundwater treatment, how to choose the appropriate treatment technique, and cost analysis of groundwater treatment. RECENT FINDINGS: Various treatment technologies have been used for the treatment of groundwater: physical, chemical, and biological technologies with different success rates. In the literature, various adsorbents have been successfully synthesized from low-cost and environmentally friendly materials. Adsorption is considered an efficient treatment technique for the removal of both toxic elements and pathogens by utilizing different adsorbents. For example, the nanostructures of MgO with a BET surface area of up to 171 m²/g obtained a very high adsorption capacity of 29,131 mg/g for fluoride ions in water, while the incorporation of iron in activated carbon has improved its adsorption capacity to 51.3 mg/g for arsenic. Moreover, certain adsorbents have shown the capability to remove 99% of the rotavirus and adenovirus from groundwater. Groundwater resources are contaminated with toxic metals and pathogens. Therefore, water treatment technologies should be evaluated for their efficiency to remove such contaminants. Determination of the most cost-effective and efficient treatment technique is not an easy task and requires the understanding of various aspects such as the contaminants present in water, the reuse options considered, and cost analysis of the treatment technique.
Показать больше [+] Меньше [-]Mussels as a tool for mitigation of nutrients in the marine environment
2014
Petersen, Jens Kjerulf | Hasler, Berit | Timmermann, Karen | Nielsen, Pernille | Tørring, Ditte Bruunshøj | Larsen, Martin Mørk | Holmer, Marianne
Long-line mussel farming has been proposed as a mitigation tool for removal of excess nutrients in eutrophic coastal waters. A full-scale mussel farm optimized for cost efficient nutrient removal was established in the eutrophic Skive Fjord, Denmark where biological and economic parameters related to nutrient removal was monitored throughout a full production cycle (1yr). The results showed that it was possible to obtain a high area specific biomass of 60tWWha−1eqvivalent to a nitrogen and phosphorus removal of 0.6–0.9 and 0.03–0.04tha−1yr, respectively. The analysis of the costs related to establishment, maintenance and harvest revealed that mussel production optimized for mitigation can be carried out at a lower cost compared to mussel production for (human) consumption. The costs for nutrient removal was 14.8€kg−1N making mitigation mussel production a cost-efficient measure compared to the most expensive land-based measures.
Показать больше [+] Меньше [-]Mechanically durable green aerogel composite based on agricultural lignocellulosic residue for organic liquids/oil sorption
2022
Chhajed, Monika | Verma, Chhavi | Sathawane, Manoj | Singh, Shiva | Maji, Pradip K.
Various oil spill cleanup sorbents have good hydrophobicity and oil separation efficiency, but their practical use has been limited due to the difficult and costly fabrication procedure. The research aims towards material development using the consumption of lignocellulosic agricultural residue for isolating cellulose nanofiber and its forward use to construct a 3D porous structure. A simple freeze-drying technique was used to assemble low-density porous structure. The biodegradable polylactic acid coating was used to alter the wettability from hydrophilic to hydrophobic and the maximum water contact angle value was around 120°. The prepared coated samples were testified for a series of oil/organic solvents-water mixtures. The sorption capacity was in the range of 28–70 g/g. The prepared aerogels were efficiently reused for at least 10 cycles. Developed material was used in continuous oil-water separation to remove oil from the water's surface. The cost analysis was estimated for scaleup production in the future.
Показать больше [+] Меньше [-]Dynamic ecological risk modelling of hydrocarbon release scenarios in Arctic waters
2020
Sajid, Zaman | K̲h̲ān, Faiṣal | Veitch, Brian
The Arctic is an ecologically diverse area that is increasingly vulnerable to damages from oil spills associated with commercial vessels traversing newly open shipping lanes. The significance of such accidents on Arctic marine habitats and the potential for recovery can be examined using ecological risk assessment (ERA) coupled with a dynamic object-oriented Bayesian network (DOOBN). A DOOBN approach is useful to represent the probabilistic relationships inherent in the interactions between key events associated with an oil spill, including oil dispersion from the source, ice-oil slick interactions, seawater-oil slick formation, sedimentation, and exposures to different aquatic life. From such analysis, a probabilistic cost analysis can be performed to examine the theoretical cost of habitat services lost and restored. The application of an ERA-DOOBN model to assess oil spills in the Arctic is demonstrated using a case study. The utility of the model output for determining habitat restoration costs and developing policy guidelines for ecological response measures in the Arctic is also discussed.
Показать больше [+] Меньше [-]Hollow fiber liquid-phase microextraction as clean-up step for the determination of organophosphorus pesticides residues in fish tissue by gas chromatography coupled with mass spectrometry
2011
Sun, Xiaojin | Zhu, Fang | Xi, Jiabin | Lu, Tongbu | Liu, Hong | Tong, Yexiang | Ouyang, Gangfeng
Hollow fiber liquid-phase microextraction (HF-LPME) technique was used as a clean-up procedure for the determination of organophosphorus pesticides (OPPs) in fish tissue. In this study, eight OPPs were first extracted with acetone from fish sample, the organic extract after rotatory evaporation was then redissolved with water–methanol (95:5, v/v) solution, followed by polyvinylidene difluoride (PVDF) HF-LPME. Experimental HF-LPME and other sample preparation conditions were carefully investigated and optimized. Under the optimum conditions, good linearity were observed in the range of 20–500ng/g, limits of detections (LODs) were in the range of 2.1–4.5ng/g. The repeatability and recovery of the method also showed satisfactory results. Compared with traditional sample preparation method for the determination of OPPs in fish tissue, the method developed in this study eliminated the solid phase extraction (SPE) step, simplified the sample preparation procedure and lowered the cost of analysis.
Показать больше [+] Меньше [-]An analytical study on municipal wastewater to energy generation, current trends, and future prospects in South Asian developing countries (an update on Pakistan scenario)
2021
Batool, Masooma | Shahzad, Laila
The water scarcity and energy crises are major challenges, particularly for South Asian developing countries. Wastewater resource recovery always remained an untapped potential for South Asian countries, especially in Pakistan. Globally, municipal wastewater’s global generation rate is about 331 km³/year; only a small proportion is treated and safely reused. Wastewater also has high energy content and can be greatly productive, whereas most of the wastewater treatment plants currently employed in developing regions are non-functional or taking high energy inputs. Many global level studies are being conducted for energy use reduction and the production of renewable energy from wastewater. In this review, installation of wastewater treatment plants is suggested in the context of economic and environmental feasibility for South Asian developing countries. Multiple factors showed the need for and high potential to installation of wastewater treatment plants for providing clean water under sustainable development goals and further to recover valuable contents from municipal wastewater. The tremendous need for infrastructure development became obvious to deliver clean water to communities that are using wastewater directly or indirectly for various purposes. Based on technical grounds, economic, social, and environmental challenges can be tackled with viable wastewater treatment plant design options in each country context. With each step of wastewater treatment, control strategies would minimize energy use and enhanced resource recovery will reduce pressure on the current natural resource base. Overall, the cost assessment, funding opportunities, research and development, and social acceptability remained the big factors to energy generation from municipal wastewater in South Asia. Graphical presentation of the study
Показать больше [+] Меньше [-]A comparative study of photo-Fenton process assisted by natural sunlight, UV-A, or visible LED light irradiation for degradation of real textile wastewater: factorial designs, kinetics, cost assessment, and phytotoxicity studies
2021
de Souza, Ziani S. B. | Silva, Maryne P. | Fraga, Tiago J. M. | Motta Sobrinho, Maurício A.
The present work aims to evaluate the treatment of the effluent from the textile industry via advanced oxidative processes of photo-Fenton assisted by different sources (natural sunlight, UV-A or visible LED lamps). To identify the best operating conditions, a factorial design was carried out for each process. It was observed that after the optimization of the processes, chemical oxygen demand (COD) removals greater than 88% were achieved. In addition, it was observed that the use of the LED lamp required lower reagent concentrations compared to solar and UV-A sources. A kinetic study was carried out under the best conditions obtained and it was observed that the sources showed rapid evolution, reaching a COD removal equilibrium with 30 min of reaction. Reagent monitoring was also carried out, and it was observed that they were not limiting to the reaction. Phytotoxicity analysis was also satisfactory since the treated effluents allowed a higher relative growth and germination index of the cucumber roots compared to the raw effluent. Finally, the cost analysis indicated that the use of LED lamps resulted in a reduction in electrical consumption compared to the UV-A lamp, as well as a reduction in the cost of reagents due to the lower concentration of reagents required compared to processes assisted by natural sunlight and UV-A.
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