Maisa El Gamal

Effect of salinity and temperature on water cut determination in oil reservoirs

In this study, system stability and water cut were evaluated via IR analysis and physicochemical properties of the tested mixture. Samples were prepared with different water cuts at a specified salinity and tested by IR. Different cations were also used in the water portion of the mixture to evaluate its effect of interaction and stability. In addition, the effect of water cut, temperature, salinity and cation type, and composition on specific gravity, API gravity, kinematic and dynamic viscosities and surface tension were investigated. The studied water content range was from 0 to 0.8 while temperature from 20 to 100 °C. Salinity effect up to 40,000 ppm was also evaluated. For each mixed ion solution, equivalent sodium concentrations and mixture resistivity were calculated. Relationships between water cut, major functional groups and mixture physicochemical properties were developed. Therefore, for a known property, water cut could be predicted.

Solidification of cement kiln dust using sulfur binder.

The present study aims to offer a new methodology for consuming two industrial wastes; sulfur, from petroleum and natural gas industries, and cement kiln dust (CKD), from Portland cement industries, in construction industry. Sulfur solidified cement kiln dust material (SSCKDM) was manufactured by mixing molten sulfur, treated sulfur, CKD and sand at a controlled temperature in excess of 120°C. The hot mixture was subsequently cast and shaped into the desired mold and was then allowed to solidify at a specified cooling rate. Solidified materials were immersed for time periods up to 28 days in distilled water at different temperatures of 25 and 60°C, sea water, and acidic and basic universal buffer solutions of pH4 and pH9, respectively. Solidified material performance as function of time and type of aqueous solution exposed to was evaluated in view of compressive strength variations and leachability of metal and heavy metal ions. The results indicated that the solidified articles exhibit homogenous and compact internal microstructure with excellent mechanical properties. However, it showed durability problem upon exposure to aqueous solution environments due to the initial chemical composition of the CKD, whose leached test showed release of relatively high amounts of sulfates and alkali metals. Durability of SSCKDM articles in relation to strength reduction and crack formations control was improved by addition of glass fiber while, the use of anti-leaching agent such as anhydrous sodium sulfide resulted in reduction of leached heavy metals without any measurable decrease in leached amounts of alkali metals and anions from the solidified matrix. Furthermore, based on leachability index method of calculation, potential chemical mobility of metal and heavy metal ions from the solidified matrix was characterized as medium.

Treatment of collapsible soils using sulfur cement

Abstract The strength and stability of collapsible soils can present problems during construction. To overcome these problems, sulfur cement as a treatment method was developed and evaluated in view of its microstructure, mineralogical composition, physical, thermal, mechanical, hydraulic, and chemical properties. The treated soil was prepared from modified sulfur, sulfur, fly ash, and soil aggregates. Specimens were treated in air, water, and saline solutions at different temperatures, ranging from room temperature to 60°C, and time, ranging from 28 days to one year. After treatment, specimens were tested for their compressive strength. The results indicated that the strength of the treated soil is about three times higher than that stabilized by normal Portland cement. The results of hydraulic conductivity of the treated soils are ranged between 1.46 × 10-13 and 7.66 × 10-11 m/s making it a good candidate for its potential use as stabilizing agent in arid lands. Leachability of sulfur and metal ions from the solidified material was below the norms stated by various environmental agencies. The treated soil offers many advantages as an alternative construction material particularly in situations that require a fast solidification in places of extremely cold, hot climates or corrosion conditions.

Microbial Degradation of Chlorophenols

Chlorophenols (CPs) are hazardous pollutant that are commonly encountered as major constituents of several types of wastewater such as industrial, refinery and pharmaceutical wastewater. They are also exposed to the environment in the form of chloro-based pesticides. CPs are considered harmful to human health due to their potential carcinogenic and toxic effects. Although some types of CPs are resistant to degradation and therefore persistent in the environment, many types of microorganisms have developed the ability to degrade them, and hence biological degradation can be exploited to remediate the environmental problems associated with CPs. Recent achievements in the degradation of CPs by microorganisms have been reviewed, focusing on the degradation mechanisms and pathways of 2, 4-dichlorophenol and Pentachlorophenol.