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waste-treatment
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Viable medical waste chain network design by considering risk and robustness
, Article Environmental Science and Pollution Research ; Volume 29, Issue 53 , 2022 , Pages 79702-79717 ; 09441344 (ISSN) ; Kargar, B ; Gharehbaghi, A ; Weber, G. W ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Medical waste management (MWM) is an important and necessary problem in the COVID-19 situation for treatment staff. When the number of infectious patients grows up, the amount of MWMs increases day by day. We present medical waste chain network design (MWCND) that contains health center (HC), waste segregation (WS), waste purchase contractor (WPC), and landfill. We propose to locate WS to decrease waste and recover them and send them to the WPC. Recovering medical waste like metal and plastic can help the environment and return to the production cycle. Therefore, we proposed a novel viable MWCND by a novel two-stage robust stochastic programming that considers resiliency (flexibility and...
Multifunctional Ag/AgCl/ZnTiO3 structures as highly efficient photocatalysts for the removal of nitrophenols, CO2 photoreduction, biomedical waste treatment, and bacteria inactivation
, Article Applied Catalysis A: General ; Volume 643 , 2022 ; 0926860X (ISSN) ; Ghasemi, S ; Hajiahmadi, S ; Rhimi, B ; Nejad, Z. G ; Karima, S ; Shahsavari, Z ; Wang, C ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Over the past few decades, biological hazards and organic pollution have become major environmental concerns. Photocatalysis has been found to be effective in minimizing the negative impacts of these issues in air and water. Lozenge shape Ag/AgCl/ZnTiO3 photocatalysts were fabricated by a facile two-step synthesis method, including hydrothermal and coprecipitation. The physicochemical characteristics and morphological properties of the structures were comprehensively described taking advantage of a multi-technique approach. The prepared photocatalysts offered excellent nitrophenol mineralization (>90%) after 90 min of visible light irradiation. Based on the spin-trapping ESR technique, •O2̅–...
Green products from herbal medicine wastes by subcritical water treatment
, Article Journal of Hazardous Materials ; Volume 424 , 2022 ; 03043894 (ISSN) ; Tavakoli, O ; Sarkhanpour, R ; Sajadi, S. M ; Zarrintaj, P ; Rabiee, N ; Akhavan, O ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Herbal medicine wastes (HMWs) are byproducts of medicine factories, which are mainly landfilled for their environmental problems. Only bearing in mind the contamination and concerns caused by the COVID-19 pandemic and environmental emissions, the worth of herbal medicine wastes management and conversion to green products can be understood. In this work, subcritical water treatment was carried out batch-wise in a stainless tube reactor in the pressure range of 0.792–30.0 MPa, varying the temperature (127–327 °C) and time (1–60 min) of extraction. This resulted in new and green material sources, including organic acids, amino acids, and sugars. Amazingly, at very low extraction times (below 5...
Effects of temperature and mixing modes on the performance of municipal solid waste anaerobic slurry digester 09 Engineering 0907 Environmental Engineering 09 Engineering 0904 Chemical Engineering
, Article Journal of Environmental Health Science and Engineering ; Volume 17, Issue 2 , 2020 , Pages 1077-1084 ; Shayegan, J ; Sharif University of Technology
Springer
2020
Abstract
Purpose: Anaerobic digestion is a promising technology for simultaneous treatment of biodegradable organic matter of municipal solid waste (MSW) and production of renewable energy. Mixing modes and temperature have influences on biogas production in anaerobic digesters treating MSW. Therefore, in this study, digester was operated at different modes of mixing and temperatures to obtain design criteria. Methods: The experiments were carried out in a semi-continuous digester. In the first part of the investigation, temperature was set at 25, 28, 31 and 34 °C. During this step, digester content was mixed in an intermittent mode by mechanical mixers. In the second part of the study, mixing...
Performance enhancement of waste heat extraction from generator of a wind turbine for freshwater production via employing various nanofluids
, Article Desalination ; Volume 478 , 2020 ; Rostami, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Water shortage issues are growing through the globe at higher rate than population growth. On the bright side, various methods are devised to capture energy from renewable energy or waste heat from different sectors. Among all inspected approaches, waste heat capturing through cooling process of the wind turbines' generators for desalination at small scale is paid less attention. However, in large wind farms, the scale of this dissipated thermal heat becomes appreciable which can drive several desalination units. Due to the above-pointed facts, the waste heat of a wind turbine with nominal capacity of 7358 kW and height of 24 m for desalinating seawater is inspected here, using a...
Triethylamine removal using biotrickling filter (BTF): effect of height and recirculation liquid rate on BTFs performance
, Article International Journal of Environmental Science and Technology ; Volume 14, Issue 8 , 2017 , Pages 1615-1624 ; 17351472 (ISSN) ; Sotoudeheian, S ; Bayat, R ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2017
Abstract
This study investigated the removal of triethylamine using a biotrickling filter. The influence of affecting parameters, such as height and recirculation liquid rate (VL) on contaminant removal efficiency, was examined in detail. The results demonstrated that in the constant empty bed residence time (EBRT), when VL was increased, the removal efficiency (RE) increased. Also, for a specific VL, increasing EBRT could also increase RE values. However, it seems that an increasing VL is a more cost-effective way to enhance RE as compared to an increasing EBRT. The obtained outcomes represented that for a constant EBRT, an increase in inlet loading (IL) could decrease RE. For lower ILs, the removal...
Determination of discharge coefficient of triangular labyrinth side weirs with one and two cycles using the nonlinear PLS method
, Article Sustainable Hydraulics in the Era of Global Change - Proceedings of the 4th European Congress of the International Association of Hydroenvironment engineering and Research, IAHR 2016, 27 July 2016 through 29 July 2016 ; 2016 , Pages 653-657 ; 9781138029774 (ISBN) ; Parvaneh, A ; Kabiri Samani, A ; Sharif University of Technology
CRC Press/Balkema
2016
Abstract
Side weirs are hydraulic control structures widely used in irrigation, drainage networks and waste water treatment plants. These structures can be used for adjusting and diverting of flow with minimum energy loss. In spite of many studies were carried out on rectangular side weirs, the studies on oblique and labyrinth side weirs are scarce. In this study, based on the experimental data from more than 210 laboratory tests and through using the multivariable nonlinear partial least square (PLS) method, two nonlinear equations are presented for discharge coefficient CM of triangular labyrinth side weirs with one and two cycles. The obtained empirical equations relating CM with the relevant...
Removal of lignin, COD, and color from pulp and paper wastewater using electrocoagulation
, Article Desalination and Water Treatment ; Volume 57, Issue 21 , 2016 , Pages 9698-9704 ; 19443994 (ISSN) ; Kariminia, H. R ; Safari, S ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
Electrocoagulation is an effective, fast, and economic method for treatment of industrial wastewaters. In this study, effects of different parameters including electrolysis time, voltage, and pH on the reduction of chemical oxygen demand (COD), lignin, and color in pulp and paper wastewaters were studied. Iron and aluminum were used as anode and cathode electrodes, respectively. Under the optimal conditions (pH 5, 60 min, 10 V), this treatment method led to 85% removal of COD and 78.5% removal of lignin. Furthermore, clear treated water with complete color removal was generated that suggests the application of electrocoagulation for industrial wastewater treatment, especially in pulp and...
Photocatalytic activity of immobilized geometries of tio2
,
Article
Journal of Materials Engineering and Performance
;
Volume 24, Issue 7
,
July
,
2015
,
Pages 2757-2763
;
10599495 (ISSN)
; Sadrnezhaad, S. K
;
Sharif University of Technology
Springer New York LLC
2015
Abstract
Photocatalysts that are used for waste water treatment are often suspended in the waste water during processing and then must be removed from the water after treatment. To reduce the post-degradation expenses and time, separation is facilitated by an immobilization process. The effect of immobilized TiO2 geometries on the photocatalytic behavior of the photocatalyst is investigated in this work. Powder, fiber, film, and network-shaped TiO2 nanocatalysts were produced by using different templates. The cellulose fiber and ceramic templates were used as substrates for fiber and film/network geometry production. The products were characterized by x-ray diffraction (XRD),...
Photocatalytic activity of mesoporous microbricks of ZnO nanoparticles prepared by the thermal decomposition of bis(2-aminonicotinato) zinc (II)
, Article Cuihua Xuebao/Chinese Journal of Catalysis ; Volume 36, Issue 5 , May , 2015 , Pages 742-749 ; 02539837 (ISSN) ; Tadjarodi, A ; Akhavan, O ; Sharif University of Technology
Science Press
2015
Abstract
Hollow microblocks of [Zn(anic)2 ], as a novel coordination compound, were synthesized using 2-aminonicotinic acid (Hanic) and zinc (II) nitrate tetrahydrate. The chemical composition of the zinc complex, ZnC12 H10 N4 O4 , was determined by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. The synthesized zinc complex was used as a precursor to produce ZnO nanostructures by calcination at 550 °C for 4 h. Morphological studies by scanning electron microscopy and transmission electron microscopy revealed the formation of porous microbricks of ZnO nanoparticles. N2 adsorption-desorption analysis showed that the...
Bioleaching kinetics of a spent refinery catalyst using Aspergillus niger at optimal conditions
, Article Biochemical Engineering Journal ; Volume 67 , 2012 , Pages 208-217 ; 1369703X (ISSN) ; Mousavi, S. M ; Yaghmaei, S ; Barati, M ; Sharif University of Technology
Elsevier
2012
Abstract
The kinetics of bioleaching of Mo, Ni, and Al from spent hydrocracking catalyst, using Aspergillus niger was studied. The four most effective bioleaching variables were selected in accordance with the Plackett-Burman design and were further optimized via central composite design (CCD). The optimal values of the variables for maximum multi-metal bioleaching were as follows: particle size 150-212. μm, sucrose 93.8. g/L, pulp density 3%. w/v, and pH 7. The maximum metal recoveries corresponding to these conditions were 99.5 ± 0.4% Mo, 45.8 ± 1.2% Ni, and 13.9 ± 0.1% Al. The relatively low Ni extraction was attributed to the precipitation of Ni in the presence of oxalic acid. Under the optimal...
Upgrading activated sludge systems and reduction in excess sludge
, Article Bioresource Technology ; Volume 102, Issue 22 , November , 2011 , Pages 10327-10333 ; 09608524 (ISSN) ; Shayegan, J ; Sharif University of Technology
2011
Abstract
Most of 200 Activated Sludge Plant in Iran are overloaded and as a result, their efficiency is low. In this work, a pilot plant is manufactured and put into operation in one of the wastewater treatment plants in the west of Tehran. Instead of conventional activated sludge, a membrane bioreactor and an upflow anaerobic sludge blanket reactor used as a pretreatment unit in this pilot. For the sake of data accuracy and precision, an enriched municipal wastewater was opted as an influent to the pilot. Based on the attained result, the optimum retention time in this system was 4. h, and the overall COD removal efficiency was 98%. As a whole, the application of this retrofit would increase the...
Crude oil desalter effluent treatment by a hybrid UF/RO membrane separation process
, Article Desalination ; Volume 238, Issue 1-3 , 2009 , Pages 174-182 ; 00119164 (ISSN) ; Roostaazad, R ; Hesampour, M ; Sharif University of Technology
2009
Abstract
Crude oil desalter effluent from a Tehran oil refinery was treated by a hybrid UF/RO membrane separation process. Ultrafiltration (UF) was used primarily to remove the emulsified oil droplets followed by the removal of total dissolved solids (TDS) via reverse osmosis (RO). The UF membrane was a hydrophilic flat sheet polysulfone ultrafiltration membrane with MWCO of 100 kDa while the RO membrane was a spiral-wound thin-film composite polyamide. Effect of operating conditions such as transmembrane pressure and crossflow velocity were studied in UF pretreatment. The experimental results showed that the UF membrane removed more than 75% of the oil and can be considered as an effective...
TiO2 nanofibre assisted photocatalytic degradation of reactive blue 19 dye from aqueous solution
, Article Environmental Technology ; Volume 30, Issue 3 , 2009 , Pages 233-239 ; 09593330 (ISSN) ; Ghaneian, M. T ; Taghavinia, N ; Khajeh Aminian, M ; Hashemian, S. J ; Sharif University of Technology
2009
Abstract
The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of...
Comparison of adsorption process by GAC with novel formulation of coagulation - Flocculation for color removal of textile wastewater
, Article International Journal of Environmental Research ; Volume 2, Issue 3 , 2008 , Pages 239-248 ; 17356865 (ISSN) ; Seif, S ; Javid, A. H ; Borghei, M ; Sharif University of Technology
2008
Abstract
This study evaluates the effectiveness of adsorption process by Granular Activated Carbon (GAC) compared with a novel formulation of coagulation - flocculation process for dye removal from textile wastewater. In this regard, acidic, reactive, disperse and direct red dye are used to prepare the synthetic dye. Dominant wave length for each dye is determined by spectrophotometeric method. Using GAC as adsorbent, equilibrium time and adsorption isotherm of each dye are determined with aid of spectrophotometric method. The results show that GAC can not remove dispersed red dye. Acidic red, direct red and reactive red of 5 mg/L concentration are removed by GAC up to %90, %88 and %43 in 30, 60 and...
Use of modified bentonite for phenolic adsorption in treatment of olive oil mill wastewater
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 30, Issue 5 , 2006 , Pages 613-619 ; 03601307 (ISSN) ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
2006
Abstract
Natural and modified clays were applied as adsorbents for the removal of organic contaminants from wastewater. This study presents an investigation on the technical feasibility of using modified minerals that are named organoclay for treatment of dissolved substances, mainly polyphenols in olive mill wastewater. The different parameters such as applied cation dosage were effective on the removal of contaminants by these adsorbents (%CEC), pollutant concentration, pH and particle size of minerals. In this investigation bentonite particles were modified by stirring the clay with a long chain quaternary ammonium cation. Doses of the applied cation varied from zero to 1.5 times the clay CEC....
Biodegradation of styrene laden waste gas stream using a compost-based biofilter
, Article Chemosphere ; Volume 60, Issue 3 , 2005 , Pages 434-439 ; 00456535 (ISSN) ; Torkian, A ; Bina, B ; Poormoghaddas, H ; Kalantary, A ; Sharif University of Technology
Elsevier Ltd
2005
Abstract
Biological treatment of waste gas styrene vapor was investigated in a three-stage bench-scale biofilter. Yard waste compost mixed with shredded hard plastics in a 25:75 v/v ratio of plastics:compost was inoculated with thickened municipal activated sludge. Microbial acclimation to styrene was achieved by exposing the system to an inlet concentration (CIn) of 0.25 g m -3 styrene and an empty bed retention time (EBRT) of 360 s for 30 days. Under steady-state conditions, maximum elimination capacity (EC) obtained was 45 g m-3 h-1 at a loading rate (L) of 60 g m -3 h-1 (CIn of 2 g m-3 and EBRT of 120 s). Reduction of retention time adversely impacted the performance resulting in the maximum EC...
Studies on recycling of zinc-containing waste
, Article REWAS'04 - Global Symposium on Recycling, Waste Treatment and Clean Technology, Madrid, 26 September 2004 through 29 September 2004 ; 2005 , Pages 2797-2799 ; 8495520060 (ISBN) ; Halali, M ; Sharif University of Technology
2005
Abstract
In this report, the possibility of recovering zinc oxide from zinc containing wastes, also the effect of temperature, time and depth of bed on recycling has been studied. Zinc oxide with a purity of 93.5% was obtained
Removal of Heavy Metal Ions and Wastewater Treatment by Using the Electrocoagulation Process
, M.Sc. Thesis Sharif University of Technology ; Ghasemian, Saloumeh (Supervisor)
Abstract
Industrial wastewater treatment has always been one of the significant human being problems for the years. In particular, sewage containing heavy metals that, if discharged into nature, would have irreversible effects on the ecosystem and human health. Due to their toxic nature, heavy metals will reduce the efficiency of wastewater treatment systems if they are not efficiently treated. Also, the removal of Nitrate from the wastewater, which is one of the most stable nitrogen oxides, has always been a serious human problem in the treatment of effluents due to their high solubility in water. The simultaneous presence of nitrate and heavy metals in the effluent will cause many problems in the...
Predicting the Optimal Operation Pattern of Municipal Wastewater Treatment Plant Using Artificial Intelligence Approaches
, M.Sc. Thesis Sharif University of Technology ; Torkian, Ayoub (Supervisor)
Abstract
With the growth of the population and the significant expansion of industries in the last century, many environmental problems have plagued developed and developing countries. One of these environmental problems is water pollution. Observing the effects of water pollution over time, sanitary and industrial wastewater treatment was proposed as a reliable solution. With technology development, wastewater treatment requirements have become stricter. The increase in energy consumption and wastewater treatment costs due to population growth and industrialization on the one hand and strict regulations, on the other hand, have forced those involved in this field to employ a variety of technical and...