Engineering and Technology Journal

Drilling fluids can be considered complex liquids containing several desired materials. These materials (small additives) are specialty products that serve a specific need, such as controlling the rheological properties of the drilling fluid and reducing corrosion for operational drilling of both oil and gas wells. Additives used to resist corrosion are called corrosion inhibitors. Previous research has shown that polymers such as Carboxymethyl Cellulose (CMC) have high characteristics of corrosion inhabitation in an aggressive environment.  In this study, the effect of adding two samples of additives, CMC and Barite, on the corrosion of carbon steel in Iraqi bentonite water base mud solution has been evaluated using the weight loss technique. The study focuses on determining and comparing the corrosion characteristics of these mud additives. All the experiments were carried out in static flow and at room temperature.  Results show that CMC works as a good inhibitor when added to bentonite/barite mud. The calculated corrosion rates of 0.95mpy, 0.75mpy, 0.53mpy, 0.49mpy were found for bentonite mud, bentonite/barite mud, bentonite/CMC mud, and bentonite/CMC/barite mud, respectively. This would result in an inhibitor efficiency of about 50%.

Corrosion processes are accountable for serious losses in the oil industry. Although organic and inorganic materials and mixed materials inhibitors have been used for a long time to control or reduce corrosion. Using nano-materials as inhibitors has gained an increasing applications role because of their exceptional properties. Nano materials are good corrosion inhibitors because they possess many advantages such as high efficiency of inhibition, low cost, minimum toxicity and effortless production. This work examines the use of nano-materials as inhibitors to prevent corrosion of carbon steel in drilling mud. Anti-corrosion properties of zinc and nickel ferrite nano materials (ZnFe2O4, Zn0.6Ni0.4Fe2O4) have been investigated over carbon steel in local Iraqi bentonite mud as a source of the corrosion. It has been found that under the given conditions, ferrites act as efficient corrosion inhibitors of carbon steel.

Brass used in heat exchanger is corroded in industrial water. The used inhibitor is extracted from horse tail herb added in different concentrations and temperature to industrial water in which heat exchanger if exposed to these conditions. Brass is studied under the above conditions using potentiodynamic polarization, scanning electron microscopy (SEM) and X-ray diffraction. Potentiodynamic polarization technique was used to evaluate the corrosion rate data. Inhibition efficiency of 92.1 % at 298 k was achieved with the addition of 1350 ppm of horse tail herb from potentiodynamic polarization measurements. Potentiodynamic curves show that the presence of extracted horse tail herb in industrial water affects both the anodic and cathodic processes, decreases the corrosion current density and shifts the corrosion potential towards more noble values; the inhibitors are mixed type inhibitors.