Drilling fluid technology
Drilling fluid technology and drilling technology is one of the important systems, in safe, efficient and economic wall. They are different techniques in drilling by industries. Drilling such as oil-well has different approaches of drilling and propless of drilling which includes: drill string torque and drag.
Drilling fluid function
- To minimize drilling damage to the reservoir
- To stabilize the wellbore (ole diameter)
- To control the formation pore damage to the reservoir.
Drilling fluids includes:
Water is a common substance in life existence that involves drilling technology. Water is also used in drilling other substances but a limiting factor in air drilling. Water has properties that are internationally accepted which can be compared in relation to other fluids which include: surface tension, heat of fusion, and solubility. Notice that water expands on freezing under normal pressure.
Bentonite is a special mineral found on earth, it is soft, greasy to touch clay. It has a fine grained structure clay component with less than 85% montmorillonite. In mud parlance, bentonite is divided into sodium or calcium bentonite but it depends on the ion that is dominant. In terms of performance, it is classified as low and high yield bentonite while in geographic origin; it is classified as southern and western bentonite.
X- ray diffraction shows that the heterogeneous nature of bentonite is separated into three fractions. When a suspension is centrifuged, the observable change was that of plastic viscosity and gel strength properties and they are influenced by surface area and exchangeable ions in the fraction.
THE ECONOMIC IMPORTANCE OF MINING AND PROCESSING BENTONITE.
Bentonite has many properties that make it economically valued. There are several publications by geological survey to bentonite occurrences and, processing and applications.
When a bentonite site is located, the instrument (auger or core drill) are used to explore the samples for evaluation or quality control analysis. If the quality analytical process is favorable, pits are lay out with considerations. These considerations are found in the API specification for oil-well drilling fluid material, API spec 13-A sevent edition.
Minable bentonite bed vary in thickness of two feet minimum, stripping depth is sixty feet maximum depending on the test result , then the soil is expose for several months (seven months), this promotes drying an improves the quality of the clay.
Composition and properties of drilling fluid & completion fluids, HCH Darley, George R. Gray. Gulf publishing company, 1988, fifth edition pp 542-563