CHAPTER ONE
1.0 INTRODUCTION
Drilling mud is a flowing fluid applied in rotary drilling for achieving single or multiple tasks during the procedure, and its typically consist of water/oil, clay, weighing compounds and few other chemical additives (American Institute of Petroleum, 1998). It most important physical characteristics are viscosity and water holding/retaining properties (Crowo, 1990). The successful and cost of the drilling process is known to depend extensively on the asset of the drilling fluid used (Gray, et al., 1980). Drilling mud circulates in a loop, from the building platform, where is forced down into the formation system by entering the drill string, and pushed up to the surface again via the drill bit.
The fluid characteristics such as density and temperature are variables that need to be regularly monitored for the perfect drilling performance according to the condition of the drilling well (Issham and Ahmad Kamal, 1997; Rabia, 1985). Drilling fluids are commonly known for their gel or thixotropic characteristics, in which they can go through a reversible transformation from high to low viscosity status when being subjected to shear stress force (Dolz et al., 2007). These transformations ruin the microstructure of the but will be gradually recovered when the fluid is in resting condition (Azar and Samuel, 2007). Usually, the industrial capability of wells is impaired by multifaceted interfaces between rock and fluid, which decrease permeability to oil and gas. For that reason, drilling mud should be continuously formulated to diminish these undesireabe effects (Hamida, Kuru, & Pickard, 2010). Depth, pressure and mechanical/impact resistance of the wellbore are the key parameters that determined which type of the mud is most relevant.
Inspite of their differences in categories, that main purposes and functions remain mutual (Barnes et al., 1998). They function to preserve hole reliability, convey the rock cuttings, managing the pressure of the mud system along with lubricating and cooling the drill bit (Baba Hamed and Belhachi; 2009; Brazzel, 2009; Caenn and Chillinger, 1996; Gonzalez et al., 2011). At the current time drilling mud are categorized by their external phase or basic material into five major groups, which are oil based drilling mud (OBM), Synthetic base drilling mud (SBM), Water based drilling mud (WBM), Gas based drilling mud (GBM) and Nano based drilling mud (Davis et al., 1984; Van Dyke and Baker, 1998).
The significant factors for distinguishing the assets of a drilling fluid are gel strength, viscosity(apparent and plastic viscosity), explicit weight, PH, thermal stability and the filtration function (Caenn et al., 2011., Sondona, 1985). Untreated colloids, basically starch and its modified types, were used in drilling fluid industry for a long time to defeat the hazardous effect of anhydrite and saline on drilling fluids (Civian, 2007; Windarto et al., 2011).Managing the fermentation made by micro-organism in drilling muds, which are composed of gums, starches and tenants additives, is one of the most important problems in drilling mud formation. In an effective stated drilling mud, depending on the PH, Heat, Ventilation group of enzymes get activated which assist microorganisms to fermentation dilemma in starch based drilling muds is generally chanlleged by adding an antiseptic like paraformaldehyde, which is fairly economical (Myers, 1962; Soepenberg et al., 1983). In drilling mud composition different polymer and chemical are used for various applications, this chemicals mostly influence the rheological and fluid loss properties of the mud (Austin, 1983).
1.1: BACKGROUND STUDY
1.1.1 GUM ARABIC
Gum Arabic, the natural exudates from Acacia Senegal, a high molecular weight heteropolysaccharide (hydrolysis result D-galatose with lesser amount of 4-o-methyl-D-glucoronic acid), shows unusual solution behavior compared to other polysaccharides of similar molecular weight. The rheology of Arabic gum has been extensively studied. Gum solution 30% shows higher solution viscosity and exhibit pseudoplasticity. Some reports are available on shear thickening behavior of Arabic gums while recently Mothe and Rao reported that the gum shows shear thining behavior at low shear rate (1-50s). The instrumental measurement of low viscosity fluids like Arabic gum solutions has been a difficult task; however, with the advent of controlled stress rheometer, it is now possible to characterize the exact flow behavior of fluids with viscosities less than ImPaS. The reports on the rheology of Arabic gum are contradictory and need further investigation. Presently, considerably attention has been given to the study of various hydrocolloids and their combinations for thickening and texture modification in gravies, dairy products, food drinks and pet foods because their rheological and functional properties are complimentary. Recent applications have proved that such blends can produce new food formulations and ingredients. Gum Arabic is compatible with most other gums due to its low viscosity characteristics.
The structure of gum Arabic contains proteinaceous material (2%) covalently joined with polysaccharide moiety. It gives a smooth flow or sometimes flow or sometimes reduces high viscosity in combination with other gums like Xanthan, gelatin, agar, guar gum and modified starches to produce various confections. The gum has been beneficial when a thin, pourable consistency is desired. The synergic effects of Arabic gum have also interested the food processing industries. The resulting rheological properties of various gums depend on the gum concentration molecular weight of the polysaccharides and functional groups, and the degree of interaction between two hydrocolloids. Associations of participating hydocolloids occur if biopolymer the interaction is favorable while mixture of the repulsive hydrocolloids exhibits thermodynamics incompatibility.
1.1.2 GINGER
Ginger (zingiber efficinale Rescoe) is a flowering plant in the family zingiberaceae whose rhizome, ginger root or simply ginger, is widely used as a spice or medicine. It is herbceous perennial which grows annual stems about a meter tall bearing narrow green leaves and yellow flowers. Ginger is indigenous to South China, and was spread eventually to the spice Islands, other parts of Asia and subsequently to West Africa and Carribean. Ginger was exported to Europe via India in the first century AD as a result of the lucrative spice trade. India is now the largest producer of ginger. Other members of the family zingiberaceae include tumeric Cardamon, and galangal. The distantly related dicots in the Gervus Asarum are commonly called wild ginger because of their similar taste. Mature ginger rhizomes are fibrous and nearly dry.
The juice from ginger roots is often used as a spice in Indian recipes and is a common ingredient of Chinese, Korean, Japanese, Vietnamese, and many South Asian Cuisines for flavoring dishes such as seafood, meat and vegetarian dishes. Ginger is an herb, the rhizome (underground stem) is used as a spice and also as a medicine. It can be used fresh, dried and powdered, or as a juice or oil. Ginger is commonly used to treat various types of stomach “problems”, including motion sickness, morning sickness, Colic, upset stomach, gas diarrhea, nausea, caused by cancer treatment, nausea and vomiting after surgery as well as loss of appetite. Other uses include pain relief from arthritis or muscle soreness, menstrual pain, upper respiratory tract infections, cough, and bronchitis. Ginger sometimes used for chest pain, low back pain, stomach pain. Some people pour the fresh juice on their skin to treat burns. The oil made from ginger is sometimes applied to the skin to relieve pain. In foods and beverages, ginger is used as a flavoring agent. In manufacturing, ginger is used as for fragrance in soaps and cosmetics. One of the chemicals in ginger is also used as an ingredient in laxative, anti-gas, and antacid medications.