Abstract. Shock chlorination is a well-known practice in swimming pools and domestic wells. One of the limitations for using this technique in drinking water purification facilities is the difficulty of quickly removing high chlorine concentrations in water distribution systems or production facilities. In order to use this method in the drinking water industry a shock de-chlorination method should be introduced for producing microorganism and biocide free water. De-chlorination using natural stagnant aeration (leaving the water to lose the chlorine naturally) is the safest known method if compared with chemical and charcoaling methods. Unfortunately, stagnant aeration is a slow process. Therefore, developing a process for accelerating de-chlorination by aeration would pave the way for using shock de-chlorination in drinking water industry. Forced air bubbling is a possible technique for de-chlorination but there is lack of data supporting such a process. The theory is that air bubbling has the advantages of higher mass transfer area, higher Reynolds number across the bubble water interface, and higher mass transfer concentration gradient as the bubbling presents a continuous stream of fresh bubbles. All of these factors accelerate aeration to various extents. A 20 cm diameter, 1-meter height column provided with air sparger was designed to collect the desired data used in this study. Trichloroisocyanuric acid, sodium hypochlorite and chlorine gas were the three familiar sources of chlorine used to investigate their response to air bubbling. Chlorine gas was the fastest and safest chlorine source to be dechlorinated. It dropped from 200 ppm to 0.02 ppm within 4 minutes or zero ppm within 6 minutes using an air flowrate of 9 l/min. Sodium hypochlorite decreased from 200 ppm to 0.02 ppm within 6 minutes using air flowrate of 9 l/min. Trichloroisocyanuric acid found to be the chlorine source slowest to respond to de-chlorination. It decreased from 200 ppm to 0.02 ppm within 8 minutes using an air flowrate of 9 l/min. Shock de-chlorination by aeration is found to be a promising method that opens up the drinking water industry and could produce microorganism and biocide free drinking water.
Direct contact membrane distillation is an effective method for production of fresh water from saline water. In this study two samples were used as feed solutions; the first one was RO waste from Al-Hilla Coca-Cola Factory (TDS= 2382 mg/l) and the other was Haji Ali drainage water (TDS= 4127 mg/l). Polytetrafluoroethylene (PTFE) hydrophobic membrane supported with polypropylene (PP) was used as flat sheet form with plate and frame cell. Results proved that membrane distillation is an effective technique to produce fresh water with high quality from brine with low salinity content. With membrane area of 8x8 cm2, the volume of treated water decreased from 34.97 ml at first half hour to 33.02 ml after 180 min of
... Show MoreTwo samples of (Ag NPs-zeolite) nanocomposite thin films have been prepared by easy hydrothermal method for 4 hours and 8 hours inside the hydrothermal autoclave at temperatures of 100°C. The two samples were used in a photoelectrochemical cell as a photocatalyst inside a cell consisting of three electrodes: the working electrode photoanode (AgNPs-zeolite), platinum as a cathode electrode, and Ag/AgCl as a reference electrode, to study the performance of AgNPs-zeolite under dark current and 473 nm laser light for water splitting. The results show the high performance of an eight-hour sample with high crystallinity compared with a four-hour sample as a reliable photocatalyst to generate hydrogen for renewable energies.
Resumen:
El presente trabajo intenta analizar las características del lenguaje jurídico español a cuya estructura se debe su complejidad. A la vez, damos una descripción detallada de sus rasgos morfosintácticos, léxico-semánticos y estilísticos. En ningún momento, pretendemos fijar unas pautas o normas para la traducción de este lenguaje que requiere unos previos conocimientos jurídicos y cierta preparación para proceder a realizar esta tarea. Nuestra intención es, simplemente, ofrecer al lector árabe una pequeña visión de lo difícil que es comprender los textos legales españoles hasta para los nativos para imaginarse las posibles dificultades a la hora de iniciar a traducirlos.
L'œuvre de fiction la plus ancienne qui nous soit restée, est aussi bien la première jamais écrite. L'épopée de Gilgamesh a été composée à l'aube de la civilisation mésopotamienne. Gilgamesh était le cinquième souverain après le déluge.
Sous son règne, trois millénaires environ avant Jésus-Christ, les Urukiens s’emparèrent des cités voisines, et formèrent ainsi ce que nous appellerions une petite nation. Pendant plus de deux mille ans, les civilisations du Proche-Orient ont fait de Gilgamesh leur héros épique. Il existe des
... Show MoreThe injection of Low Salinity Water (LSWI) as an Enhanced Oil Recovery (EOR) method has recently attracted a lot of attention. Extensive research has been conducted to investigate and identify the positive effects of LSWI on oil recovery. In order to demonstrate the impact of introducing low salinity water into a reservoir, simulations on the ECLIPSE 100 simulator are being done in this work. To simulate an actual reservoir, an easy static model was made. In order to replicate the effects of injecting low salinity water and normal salinity, or seawater, the reservoir is three-phase with oil, gas, and water. It has one injector and one producer. Five cases were suggested to investigate the effect of low salinity water injection with differen
... Show MoreThe alteration in the hydrological regime in Iraq and the anthropogenic increasing effect on water quality of a lotic ecosystems needs to continuous monitoring. This work is done to assess the water quality of Tigris River within Baghdad City. Five sites were selected along the river and ten physicochemical parameters and Overall Index of Pollution (OIP) were applied to assess the water quality for the period between November 2020 and May 2021, the studied period were divided into dry and wet seasons. These parameters were water temperature, pH, dissolved oxygen (DO), biological oxygen demand (BOD), total hardness, alkalinity, turbidity, total phosphorus, total nitrogen, electrical co
El sumario
“la lluvia amarilla” en una novela española que es una obra biográfica de un Aldeano hombre muerte, Andrés, quien niega abandonar su pueblo, Ainielle, y después la muerte de su esposa, la vida estaba difícil y las memorias comenzaron a perseguirlo, sus Los familiares de los fallecidos comenzaron a venir en su imaginación y sentarse delante de la chimenea y le llame a ir con ellos.
Nuestra novela del autor Julio Llamazares es llena de figuras retoricas y para dar un profundo visión de las metáforas principales que son (la lluvia, el color amarillo y la soga) realizamos un estudio analítico con el Corán sagrado y hemos visto los riesgos de las diferencias y similitudes en los
... Show MoreMany managers in geometrical and technical organizations prefer to deal with quantitative values to choose between the available options and choose the best alternative to avoid randomization and bias in decision making. One of them Baghdad Water Department, which seeks to develop the quality of its product (drinking water) and achieve its objectives under increasing growing population and the demand for water, Some of TQM tools, especially the statistical, have this ability because there is chance to use historical data and experiment of employees in Application . Two statistical tools were applied: the nominal group technique, matrix data analysis technique as well as the brainstorming tool to search for the best o
... Show MoreThis research focuses on shedding light on the most important criteria by which the translator can achieve total success with regard to the translation of scientific texts whose written language in Spanish is greatly influenced by expressions and words adopted from the English language and other world languages, in addition to exposing the most outstanding difficulties that translators face when translating from Spanish to Arabic, giving the most appropriate solutions in this regard.
Resumen
El presente trabajo de investigación se centra en echar luz sobre los criterios más importantes por los cuales el traductor puede conseguir el total éxito en la traducción de los textos científicos cuyo lenguaje
... Show MoreThe separation of fluid-fluid mixtures is a major issue in various sectors. The liquid-liquid hydro-cyclone has a wide range of applications in various sectors due to its great efficiency in separating fluid mixtures, ease of installation, and low cost. In crude oil production, high water is consumed following the degrading of production quality, high processing costs, costs, and environmental impacts. Axial hydro cyclone is a tool for Downhole Oil/Water Separation (DOWS) in the petroleum production industry, but it has limitations. The main purpose of this work is to simulate the effect of compacting the conventional inline hydro cyclone with a converging-diverging nozzle on the oil/water dynamic flow and the separation process to
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