Aiman Eid Al-Rawajfeh

Integrated Salts Precipitation and Nano-Filtration as Pretreatment of Multistage Flash Desalination System

In this paper, the effect of salts precipitators (SP) and nano-filtration (NF) on the scale deposits of multistage flash (MSF) is studied using the Skillman index for estimating the likelihood of calcium sulfate scaling. The analysis was carried out to study the sulfate scale potential for seawater with 0 to 100% pretreated make-up in an MSF reference plant. The results showed that the scale potential increases with increasing temperature and decreases with increasing the percentage of either SP or NF-treated feed. For seawater with no feed pretreatment, the scale can start depositing at 115°C. However, the maximum top brine temperature (TBT), at which sulfate scale begins to precipitate, is shifted to higher temperatures with increased pretreated portion. For 100% SP-treated feed, TBT reached 170°C. The temperature is shifted to 120, 135, and 145°C when the NF-treated portion increases to 10, 25, and 50%, respectively. For 100% NF feed pretreatment, TBT can reach as high as 175°C.

UNDERSTANDING CACO3-Mg(OH)2 SCALE FORMATION: A SEMI-EMPIRICAL MINDO-FORCES STUDY OF CO2-H2O SYSTEM

In this work, the CO 2 -H 2 O system species and the preferential precipitation of either CaCO 3 or Mg(OH) 2 have been studied by the MINDO-Forces method. The calculations were carried out using the standard MINDO-Forces procedure with standard parameters for the included atoms. The potential energies of the LUMO of CO 2 , , and are positive, and this clearly indicates that there is a kinetic barrier to overcome. The activation energy (Ea) of the reaction of H 2 O with CO 2 is about 14.3 eV and this indicates that the reaction is not likely to occur. On the other hand, the reaction of hydroxide ion with CO 2 has a much smaller activation energy (3.4 eV). When the two reactions run simultaneously, the one with lower activation energy occurs preferentially. The pH value plays a decisive role in Mg(OH) 2 scale precipitation. At higher pH, the alkaline mechanism is predominant, and the net reaction ( ) is preferred. Increasing the temperature has similar effect since the pH value increases due to the CO 2 release. Values of pH in the evaporator stages were 0.2 to 0.7 unit higher than seawater feed. At high pH values, Mg(OH) 2 precipitates preferentially.

Influence of roller burnishing on surface properties and corrosion resistance in steel

Purpose – Roller burnishing (RB) is a finishing treatment method that is used to impart certain physical and mechanical properties, such as surface roughness, improved visual appearance, or increased corrosion, friction, wear, and fatigue resistance. The purpose of this paper is to study, the influence of RB on corrosion resistance in A53 steel in HCl solution.Design/methodology/approach – Microhardness (MH), microstructure, weight loss, and potentiostatic polarization are investigated at pressing forces of 40, 60, 80, 100 and 120 N.Findings – MH increases with increasing the applied force and the percentage improvements are found to be 12, 24, 28, 35 and 65 percent for 40, 60, 80, 100 and 120 N RB pressing forces, respectively. Weight losses, in general, showed an optimum value at about 80 N. Corrosion potential and corrosion current decrease with increasing pressing force and reached a minimum at about 80 N, then begin to increase with increasing RB force.Originality/value – The results present in this ...

Mechanochemical Synthesis of Slow-Release Fertilizers: A Review

Explanation: The effect of mineral fertilizers on the environment and on living species will be discussed. Moreover, various aspects related to fertilizers production and applications are illustrated. It is found that solid-solid mechanical interaction initiates chemical reactions by lowering their energy of activation when compared to other thermochemical processes. Since milling is an important industrial operation, its contribution to materials processing is discussed.

Current status of nanotechnology in Jordan

Purpose – The current status of nanotechnology research and development in Jordan is analyzed. In recent years, Jordanian institutions demonstrated considerable interest in the development and production of nanotechnology. Here the purpose of this paper is to provide detailed information about the status of nanotechnology in Jordan in terms of several factors that influence selectivity in nanotechnology and the number of published peer-reviewed research articles. Design/methodology/approach – Several factors that influence selectivity in nanotechnology and the number of published peer-reviewed research articles were analyzed. A detailed analysis of the collected data reveals that the number of publications, citations, and patents is highly dependent on the amount of research fund. Findings – The development in nanotechnology is associated with presence and accessibility of sensitive laboratory equipment. The nanotechnology research output in Jordan is still lower than it should be due to the lack of neces...