Oil/water emulsions are one of the major threats to environment nowadays, occurs at many stages in the production and treatment of crude oil. The oil recovery process adopted will depend on how the oil is present in the water stream. Oil can be found as free oil, as an unstable oil/water emulsion and also as a highly stable oil/water emulsion. The current study was dedicated to the application of microbubble air flotation process for the removal of such oily emulsions for its characters of cost-effective, simple structure, high efficiency and no secondary pollution. The influence of several key parameters on the process removal efficiency was examined, namely, initial oil concentration, pH value of the emulsion, and the effect of adding sodium chloride. The effect of bubble size on the performance of the separation process and its impact on removal efficiency was also investigated. The results demonstrated that removal efficiency obtained by using microbubbles flotation was higher by factor of 1.72 in comparison with that achieved with fine bubbles. The removal efficiency of oil droplets was increased with the increasing of flotation time and initial oil concentration. The removal efficiency reached up 60.68% under alkaline conditions (pH≈9), and it increased to around 75% by decreasing the emulsion acidity to around (pH≈3). The addition of sodium chloride has a significant influence to the efficiency of the flotation process. The efficiency could be reached to about 84% by adding 1 gL−1of NaCl to the emulsion. While increasing the NaCl concentration to 9 gL−1resulted in reduction in removal efficiency to around 80%.
BACKGROUND: Cochlear implant has become a routine procedure for management of severe sensorineural hearing loss. Cochlear implant extrusion is one of the most devastating complication of this procedure. A double layer closure of pericranial flap and scalp rotational flap has being showed to decrease the rate of late implant extrusion.OBJECTIVE:The purpose of this study is to evaluate the use of the pericranial flap as second layer coverage after cochlear implant extrusion.PATIENTS AND METHODS:Eight patients with cochlear implant extrusion in Al-Shaheed Gazi Al-Hariri hospital were operated on by using two layer closure ; the pericranial flap as salvage layer used to cover the cochlear implant and scalp rotational flap as a routine coverage,
... Show MoreThis research presents a study in ultra-desulfurization of diesel fuel produced from conventional hydro desulfurization process, using oxidation and solvent extraction techniques. Dibenzothiophene (DBT) was the organosulfur compound that had been detected in sulfur removal. The oxidation process used hydrogen peroxide as an oxidant and acetic acid as homogeneous catalyst . The solvent extraction process used acetonitrile (ACN) and N-methyl – 2 - pyrrolidone (NMP) as extractants . Also the effect of five parameters (stirring speed :150 , 250 , 350 , and 450) rpm, temperature (30 , 40 , 45 , and 50) oC, oxidant/simulated diesel fuel ratio (0.5 , 0.75 , 1 , and 1.5) , catalyst/oxidant ratio(0.125,0.25,0.5
... Show MoreThe objective of this study is to investigate the application of advanced oxidation processes (AOPs) in the treatment of wastewater contaminated with furfural. The AOPs investigated is the homogeneous photo-Fenton (UV/H2O2/Fe+2) process. The experiments were conducted by using cylindrical stainless steel batch photo-reactor. The influence of different variables: initial concentration of H2O2 (300-1300mg/L), Fe+2(20-70mg/L), pH(2-7) and initial concentration of furfural (50-300 mg/L) and their relationship with the mineralization efficiency were studied.
Complete mineralization for the system UV/H2O2/Fe+2 was achieved at: initi
... Show MoreOrganofluorines, as a pollutant, belongs to a group of substances which are very difficult to neutralize. They are part of many products of everyday use and for this reason they pollute the environment in large quantities. Perfluorinated carboxylic acids are entered into the list of the “Stockholm Convention on Persistent Organic Pollutants” in order to minimize the load on the environment by significantly reducing their use, up to their complete rejection. The DD4 strain was isolated from the soil by the enrichment method and identified using 16S rRNA method as Pseudomonas plecoglossicida. It is able to metabolize perfluorooctanoic acid (PFOA) as the only carbon source in Raymond nutrient medium with a concentration of 1000
... Show MoreIn this research we prepared nanofibers by electrospinning from
poly (Vinyl Alcohol) /TiO2. The spectrum of the solution (Emission)
was studied and found to be at 772 nm, several process parameters
were such as concentration of TiO2 , and the effect of distance from
nozzle tip to the grounded collector (gap distance). The result of the
lower concentration of, the smaller the diameter of nanofiber is.
Increasing the gap distance will affect nanofibers diameter
AG Al-Ghazzi, 2009
This study was done to investigate the impact of different nanoparticles on diesel fuel characteristics, Iraqi diesel fuel was supplied from al-Dura refinery and was treated to enhance performance by improving its characteristics. Two types of nanoparticles were mixed with Iraqi diesel fuel at various weight fractions of 30, 60, 90, and 120 ppm. The diesel engine was tested and run at a constant speed of 1600 rpm to examine and evaluate the engine's performance and determine emissions. In general, ZnO additives' performance analysis showed they are more efficient for diesel fuel engines than CeO. The performance of engine diesel fuel tests showed that the weight fraction of nanoparticles at 90 and 120 ppm give a similar
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