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3.
Environ Manage ; 67(3): 477-488, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32856093

RESUMO

Water scarcity in Jordan is becoming more severe with time, which resulted in an indispensable need for economic innovative approaches to maximize the utilization of nonconventional water resources through reuse options. Within the framework of the current study, a novel vertical flow constructed wetland system was implemented for greywater treatment in four different rural areas in Jordan. In this paper, the primary objective was to develop a regression-based nonlinear model to predict BOD effluent concentration from the proposed system. The model obeyed the first-order kinetics and found to provide an efficient tool in predicting the effluent BOD value as exemplified by an R2 of 0.78. Moreover, a cost analysis was carried out to verify the feasibility of the proposed system. The economic results revealed a NPV range of 295-1209 JOD (420-1730$), IRR range of 6-10.7%, and a payback period range of 8.8-15.5 years. The average calculated costs of greywater treatment using the VFCWs were found to be 0.391 (USD/m3 treated) and 0.672 (USD/kg BOD removed). Finally, the energy saving from using the proposed system was quantified and an estimate of 70 JOD (100$)/year household was obtained.


Assuntos
Purificação da Água , Áreas Alagadas , Jordânia , Eliminação de Resíduos Líquidos
4.
Environ Technol ; 42(26): 4170-4178, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32200694

RESUMO

Slaughterhouse processes produce substantial amounts of high organic strength wastewater due to high COD level. A fundamental work had been carried out to explore the removal of COD from actual poultry slaughterhouse wastewater by ultrasound irradiation. The effect of applied frequency, power density, irradiation time, pH, and adding H2O2 on COD removal was investigated. The COD removal reached ultimate levels after irradiation time of 180 min. The COD removal percentage increased from 2% to 43% and from 2% to 49% when the power density increased from 160 to 1200 W/L at working frequencies of 1142 and 578 kHz, respectively. Increasing the pH from 7 to 9 reduced the COD removal from 51% to 13%. At low power densities, the high frequency (1142 kHz) was more efficient in COD removal than low frequency (578 kHz) and vice versa at high power densities. A combined system of US and H2O2 was more effective in removing COD than US standalone system. Finally, the kinetics of the COD decay using sonication was found to obey the first-order model. In conclusion, the US can be used efficiently at least to pretreat slaughterhouse wastewater with a COD removal of about 50%.


Assuntos
Matadouros , Águas Residuárias , Peróxido de Hidrogênio/análise , Oxirredução , Sonicação , Eliminação de Resíduos Líquidos
5.
Sci Total Environ ; 761: 143229, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33160673

RESUMO

Industrial processes generate toxic organic molecules that pollute environment water. Phenol and its derivative are classified among the major pollutant compounds found in water. They are naturally found in some industrial wastewater effluents. The removal of phenol compounds is therefore essential because they are responsible for severe organ damage if they exist above certain limits. In this study, ground Ziziphus leaves were utilized as adsorbents for phenolic compounds from synthetic wastewater samples. Several experiments were performed to study the effect of several conditions on the capacity of the Ziziphus leaves adsorbent, namely: the initial phenol concentration, the adsorbent concentration, temperature, pH value, and the presence of foreign salts (NaCl and KCl). The experimental results indicated that the adsorption process reached equilibrium in about 4 h. A drop in the amount of phenol removal, especially at higher initial concentration, was noticed upon increasing the temperature from 25 to 45 °C. This reflects the exothermic nature of the adsorption process. This was also confirmed by the calculated negative enthalpy of adsorption (-64.8 kJ/mol). A pH of 6 was found to be the optimum value at which the highest phenol removal occurred with around 15 mg/g at 25 °C for an initial concentration of 200 ppm. The presence of foreign salts has negatively affected the phenol adsorption process. The fitting of the experimental data, using different adsorption isotherms, indicated that the Harkins-Jura isotherm model was the best fit, evident by the high square of the correlation coefficient (R2) values greater than 0.96. The kinetic study revealed that the adsorption was represented by a pseudo-second-order reaction. The results of this study offer a basis to use Ziziphus leaves as promising adsorbents for efficient phenol removal from wastewater.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Ziziphus , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Fenol , Fenóis , Folhas de Planta/química , Água , Poluentes Químicos da Água/análise
6.
Environ Technol ; : 1-11, 2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33095684

RESUMO

Jordan is facing severe challenges in terms of water scarcity and wastewater management. Thus, there is a growing need for adopting innovative approaches to overcome these challenges. Within the framework of this study, a pilot project was implemented to treat household greywater in rural areas in Jordan with a purpose of reuse for irrigation. The project consists of designing and developing four vertical flow constructed wetland (VFCW) systems located in different sites and integrating them in a decentralized treatment system. The project work aims particularly to present a model of an innovative, compact and effective modified VFCW system. The performance of the systems was assessed by analyzing the quality of the influent and effluent streams through testing 19 water quality parameters. The results revealed that the design was adequate and efficient in treating greywater as exemplified by removal efficiencies of 90%, 90% and 92% for BOD, COD and TSS respectively. Moreover, the other physico-chemical parameters (T-N, T-P, N-NO3-, Turbidity, Ca, Mg, SO4-, and heavy metals) measured in the effluent streams complied all with the Jordanian standards for unrestricted irrigation. Therefore, the outcomes of the current study can be invested to support the use of constructed wetlands in Jordan as a sustainable technology to improve the wastewater management practices and reinforce the decentralized wastewater treatment approach in rural areas.

7.
Water Sci Technol ; 81(10): 2250-2259, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32701502

RESUMO

Ultrasound (US) is being considered as a promising emerging advanced oxidation process to degrade persistent organic-pollutants. This paper investigated the effect of several operating parameters on the degradation of a recalcitrant pharmaceutical product, namely ibuprofen (IBP), using an ultrasound-assisted biological reactor. The tested operating parameters are the power density (960, 480) W/L, US frequency (1,142, 860, 578) kHz, working volume (500, 250) mL, initial IBP concentration (30, 60) mg/L, and pH (8.2, 4). It was observed that the IBP degradation was directly influenced by the power density, and the highest degradation efficiency (99%) was obtained at 960 w/L. However, the degradation of IBP at sonication time of 120 min was found to increase from 39% to 96% while decreasing the US frequency from 1,142 to 578 kHz. The working volume had no clear effect on the IBP degradation. The optimal pH was found to be 4, which resulted in 99.5% IBP degradation efficiency after 120 min of sonication time. The degradation of IBP followed the first order kinetics. Finally, the sonically-treated water was fed to a subsequent aerobic biological reactor. The results revealed that the remaining chemical oxygen demand (COD) after sonication was lowered in the biological reactor by a percentage of 47%.


Assuntos
Poluentes Químicos da Água/análise , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Ibuprofeno , Água
8.
Sci Total Environ ; 688: 1327-1334, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726562

RESUMO

Olive mills wastewater (OMW) causes a serious environmental problem in the olive oil producing countries. This is due to its high organic matter content (COD), acidic pH values, suspended solids and high content of phytotoxic and antibacterial phenolic compounds. In this study, titanium dioxide (TiO2) as an adsorbent to reduce the COD value of the olive mill wastewater was investigated. Several variables were studied including the removal efficiency, effect of the initial COD value, amount of TiO2, temperature and pH value. The results revealed that the adsorption reached equilibrium within <120 min. Isotherm studies showed that the adsorption equilibrium data is in agreement with Freundlich isotherm. In addition, the results showed that the adsorption process was spontaneous and exothermic. The kinetic study indicated that adsorption did follow a pseudo-second order reaction. Variation of the amount of the TiO2 showed that using of 1.5 and 2 g/L of TiO2 caused the COD to drop from 1000 ppm to about 100 ppm (equilibrium concentration) in about 120 min. However, the use of 1 g/L of TiO2 exhibited almost the same effect on the COD-uptake, and the equilibrium concentration was about 400 ppm. The COD uptake was found to be inversely proportional with the temperature, pH value and the addition of salts such as sodium chloride (NaCl) and potassium chloride (KCl).

9.
Biomed Microdevices ; 21(4): 80, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31418067

RESUMO

Blood viscosity measurements are crucial for the diagnosis and understanding of a range of hematological and cardiovascular diseases. Such measurements are heavily used in monitoring patients during and after surgeries, which necessitates the development of a highly accurate viscometer that uses a minimal amount of blood. In this work, we have designed and implemented a microfluidic device that was used to measure fluid viscosity with a high accuracy using less than 10 µl of blood. The device was further used to construct a blood viscosity model based on temperature, shear rate, and anti-coagulant concentration. The model has an R-squared value of 0.950. Finally, blood protein content was changed to simulate diseased conditions and blood viscosity was measured using the device and estimated using the model constructed in this work. Simulated diseased conditions were clearly detected when comparing estimated viscosity values using the model and the measured values using the device, proving the applicability of the setup in the detection of rheological anomalies and in disease diagnosis.


Assuntos
Viscosidade Sanguínea/efeitos dos fármacos , Heparina/farmacologia , Dispositivos Lab-On-A-Chip , Modelos Biológicos , Resistência ao Cisalhamento , Temperatura , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Dimetilpolisiloxanos , Relação Dose-Resposta a Droga , Desenho de Equipamento , Nylons
10.
Water Sci Technol ; 76(11-12): 3227-3235, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29236002

RESUMO

A non-sacrificial boron-doped diamond electrode was prepared in the laboratory and used as a novel anode for electrochemical oxidation of poultry slaughterhouse wastewater. This wastewater poses environmental threats as it is characterized by a high content of recalcitrant organics. The influence of several process variables, applied current density, initial pH, supporting electrolyte nature, and concentration of electrocoagulant, on chemical oxygen demand (COD) removal, color removal, and turbidity removal was investigated. Results showed that raising the applied current density to 3.83 mA/cm2 has a positive effect on COD removal, color removal, and turbidity removal. These parameters increased to 100%, 90%, and 80% respectively. A low pH of 5 favored oxidants generation and consequently increased the COD removal percentage to reach 100%. Complete removal of COD had occurred in the presence of NaCl (1%) as supporting electrolyte. Na2SO4 demonstrated lower efficiency than NaCl in terms of COD removal. The COD decay kinetics follows the pseudo-first-order reaction. The simultaneous use of Na2SO4 and FeCl3 decreased the turbidity in wastewater by 98% due to electrocoagulation.


Assuntos
Matadouros , Boro/química , Diamante , Resíduos Industriais/análise , Águas Residuárias/química , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Eletrodos , Eletrólitos/química , Cinética , Oxidantes , Oxirredução , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos
11.
J Med Biol Eng ; 37(6): 843-857, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29541014

RESUMO

This paper presents an accurate nonlinear classification method that can help physicians diagnose seizure in electroencephalographic (EEG) signal characterized by a disturbance in temporal and spectral content. This is accomplished by applying four steps. First, different EEG signals containing healthy, ictal and seizure-free (inter-ictal) activities are decomposed by empirical mode decomposition method. The instantaneous amplitudes and frequencies of resulted bands (intrinsic mode functions, IMF) are then tracked by the direct quadrature method (DQ). In contrast to other approaches, DQ cancels the effect of amplitude modulation on frequency calculation. The dissociation between instantaneous amplitude and frequency information is therefore fully achieved to avoid features confusion. Afterwards, the Shannon entropy values of both sets of instantaneous values (amplitudes and frequencies)-related to every IMF-are calculated. Finally, the obtained entropy values are classified by random forest tree. The proposed procedure yields 100% accuracy for (healthy)/(ictal) and 98.3-99.7% for (healthy)/(ictal)/(interictal) classification problems. The suggested method is hence robust, accurate, fast, user-friendly, data driven with open access interpretability.

12.
Biotechnol Lett ; 31(1): 57-63, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18773146

RESUMO

A phenanthrene-degrading Mycobacterium sp. strain 6PY1 was grown in an aqueous/organic biphasic culture system with phenanthrene as sole carbon source. Its capacity of degradation was studied during sequential inoculum enrichments, reaching complete phenanthrene degradation at a maximim rate of 7 mg l(-1) h(-1). Water-oil emulsions and biofilm formation were observed in biphasic cultures after four successive enrichments. The factors influencing interfacial area in the emulsions were: the initial phenanthrene concentration, the initial inoculum size, and the silicone oil volume fraction. The results showed that the interfacial area was mainly dependent on the silicone oil/mineral salts medium ratio and the inoculum size.


Assuntos
Adaptação Fisiológica , Técnicas Bacteriológicas/métodos , Meios de Cultura/química , Mycobacterium/metabolismo , Fenantrenos/metabolismo , Biodegradação Ambiental , Biofilmes , Óleos de Silicone/química
13.
Appl Microbiol Biotechnol ; 78(5): 881-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18256822

RESUMO

In the present paper, the degradation of phenanthrene, a model polycyclic aromatic hydrocarbon compound, by the Mycobacterium strain 6PY1 was optimized in a biphasic culture medium. The optimization and modeling were performed using the design of experiments methodology. The temperature, the silicone oil/mineral salts medium volume ratio, and the initial cell concentration, were used as the central composite design parameters. In all experiments, the phenanthrene was degraded to undetectable levels. Response surface methodology was successfully employed to derive an empirical model describing the rate and time of degradation and to deduce the optimal degradation conditions. As a result of the optimization processes, the optimal responses for the degradation rate, the volumetric degradation rate, and the 90% degradation time were estimated to be 0.172 mg h(-1), 22 mg l(-1) h(-1), and 18 h, respectively.


Assuntos
Meios de Cultura/química , Modelos Biológicos , Mycobacterium/metabolismo , Fenantrenos/metabolismo , Biodegradação Ambiental
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