The chemical composition of guar gum is that of an exopolysaccharide, comprising of sugar, galactose, and mannose. The backbone has a linear chain of β- 1, 4-linked mannose residues to which galactose residues are 1, 6-linked at every second mannose to form short side-branches.
Guar gum has the ability to form viscous colloidal solutions when hydrated in cold water systems. The extra galactose branch points in its structure make it highly soluble. It is used extensively as a thickening agent, in food applications, for nutritional & medical effects, etc. serving a plethora of industries.
Summary: The structure of the guar gum gives it several advantages. The backbone of guar forms short side branches and has the ability to form a viscous colloidal solution when hydrated in cold water. It is used as a thickening agent, for medical effects, etc. in several industries.
Guar Gum in Oil Well stimulation:
Well stimulation is an intervention performed on the oil or gas well to augment the production. They facilitate the flow of hydrocarbons from the reservoir into the wellbore. This operation can be performed by using a well stimulator or by making use of drilling vessels, known as well stimulation vessels. Guar gum is widely used in oil well stimulation due to its properties, such as- fluid and water loss control, viscosity control, lubrication. They are used as a gelling agent and effectively reduces gel lumping tendencies.
Guar Gum in Mud Drilling:
Mud drilling is used in geotechnical engineering and is used for easing out the process of drilling boreholes into the earth. Drilling mud is also known as drilling fluid and are classified into 3 categories. They are- water-based muds (WBs), which can be dispersed and non-dispersed; non-aqueous muds, usually called oil-based muds (OBs); and gaseous drilling fluid, allowing a wide range of gases to be used. Various drilling fluid like air, water, water-based mud (WBM), oil-based mud (OBM), etc. are used falling in different categories. The oil-based mud in the most preferred and common drilling mud used. Several chemicals are added to them as they contain a high level of benzenes making them highly toxic to dispose of in an environmentally friendly manner. Guar gum powder as an emulsifier is added to the oil-based muds to serve the need making it a very effective additive.
Guar Gum in Oil Well Fracturing:
Oil well fracturing is a stimulation technique in which a rock, with the help of a pressurized liquid, is fractured. The high-pressure fracking fluid is injected into a wellbore which creates a crack in the deep-rock formation. This allows natural gas, petroleum, etc. to flow more freely. A hydraulic fracture is made by pumping fracturing fluid into the wellbore at a sufficient rate in order to increase the pressure at target depth to exceed that of the fracture gradient. The proppant is mixed with an injected fluid to maintain the fracture width. Various additives are added to fracturing fluids and guar gum is one such additive. It is mixed with the fracturing fluids and increases its viscosity. This ensures that the proppant is delivered into the formation more efficiently.
Summary: Guar Gum finds application in Oil Well Stimulation, Mud Drilling, and Oil Well Fracturing. It is used as a gelling agent in Oil well stimulation. For mud drilling, it acts as an emulsifier. It is also used as an additive in fracturing fluids for oil well fracturing.
The Bottom line: Guar gum is a good gelling agent and emulsifier and finds many applications, such as in Oil well stimulation, mud drilling, oil well fracturing, etc. It mostly increases the viscosity and helps make the entire process more efficient.