The Role of Gilsonite in Drilling and Mining: Benefits and Applications

General Description of Gilsonite Drilling Fluid Loss Control 

Drilling mud also called drilling fluid, in petroleum engineering, is a heavy, viscous fluid mixture that is used in oil and gas drilling operations to carry rock cuttings to the surface and also to lubricate and cool the drill bit. Drilling muds are traditionally based on water, either freshwater, seawater, naturally occurring brines, or prepared brines. Many muds are oil-based, using direct products of petroleum refining such as diesel oil or mineral oil as the fluid matrix.

For many years, Gilsonite has been used in the oilfield as an additive in drilling fluids. Gilsonite, in various grades and formulations, has been used to combat borehole instability problems, provide lubricity, especially in highly deviated holes, and more recently as a bridging agent to combat differential pressure sticking and provide a law invasion coring fluid. It has been well documented that appropriately formulated Gilsonite products can minimize hole collapse in formations containing water-sensitive, sloughing shales and reduce stuck pipe problems by forming a thin wall cake and an inter-matrix filter cake.
Gilsonite products are currently being widely used in water-based, oil-based, and synthetic-based mud systems worldwide. Blended Gilsonite has proved to be very effective in all water-based systems.

The drilling mud, by hydrostatic pressure, also helps prevent the collapse of unstable strata into the borehole and the intrusion of water from water-bearing strata that may be encountered. A typical water-based drilling mud contains a clay, usually bentonite, to give it enough viscosity to carry cutting chips to the surface, as well as a mineral such as a barite (barium sulfate) to increase the weight of the column enough to stabilize the borehole.

Gilsonite is utilized in drilling fluids primarily to combat the challenge of fluid loss into the formation during drilling. When drilling through porous or fractured rock formations, the drilling fluid can escape into the surrounding formation, leading to instability, higher costs, and safety concerns. Gilsonite serves as a versatile solution to this issue.

Gilsonite is used as a FLUID LOSS CONTROL (gilsonite drilling muds) additive or FLC in Oil-Based drilling muds (OBM)

It can be applied according to its hydrocarbon nature and the proper softening point to cause a significant decrease in the loss of fluids during the drilling process. The Gilsonite Solubility in Oil matters (measured by solving in TCE, CCL4 & CS2) allows the additive to act well with the oil material of the drilling mud, in most cases diesel. Also, the same characteristics result in the composition of Gilsonite powder in synthetic-based muds (SBM) since the base material is a polymer. The current grades of American Gilsonite in the Oil drilling sector are: Gilsonite XM-P, Gilsonite GM-P, Gilsonite LM-P, and Gilsonite HT series which have an equivalent supply of Iranian Gilsonite.

Advantages of Using Gilsonite as Fluid Loss Controller in Drilling Muds (OBM & SBM)

The high softening point of Gilsonite (160 degrees Celsius and above) results in over 50% fluid loss reduction compared to other additives.
Being a non-toxic material, Gilsonite adapts best to HSE limitations applied to Oil Based and Synthetic Based muds.
Elevates filter cake expansion.
Acts as Shale Stabilizer
Using Gilsonite is very cost-effective as FLC additive.

Gilsonite drilling fluid additive that provides all of these benefits:

• Controls fluid loss and seepage
• Stabilizes shales
• Prevents lost circulation
• Strengthens the wellbore to increase wellbore stability
• Minimizes differential sticking
• Promotes effective filter cake development
• Performs in oil- and water-based drilling muds
• Performs in HP/HT environments
• Minimizes HSE risks

Gilsonite Usage in Oil Sector

Gilsonite is used in drilling mud fluids and oil well cementing. Gilsonite, in a range of softening points and particle sizes, is a standard ingredient in oil-based drilling muds used in shales and other difficult geological formations. The addition of specially-treated Gilsonite to water-based drilling fluids helps minimize hole washout by stabilizing troublesome shales and sealing off highly permeable sands while reducing torque and drag. The addition of Gilsonite to oil well cement reduces slurry weight without loss of compressive strength and acts as an effective bridging and plugging agent to seal fractures in weak formations while cementing.

The role of drilling mud

Today, drilling fluid must meet at least ten requirements to be considered a good fluid.

• Cleaning of wells and transporting carcasses to the ground.
• Placing the wall and preventing it from slipping into the well and preventing the drilling mud filter from entering and causing damage to the tank.
• keeping the drill bit cool and clean during drilling.
• Oil drilling and drilling pipes.
• Control of underground pressures.
• Floating drilling rigs and fluid weight gain materials when pumps are off to prevent sedimentation, which can lead to drilling blockage and eventually residual or loss of wells.
• Hydraulic power transfer of pumps to drill by jet impact mechanism.
• tolerate part of the weight of pipes according to their buoyancy properties.
• Reduce waste on adjacent formations.

The main functions of drilling fluids include providing hydrostatic pressure to prevent formation fluids from entering into the well bore .

There are basically three types of drilling mud:

1. Oil-based-Muds – OBM: The base material is an Oil product, such as diesel oil
2. Water-Based-Muds – WBM: The base material is water
3. Synthetic-Based-Muds – SBM: Base materials are polymers

Oil-based Muds (OBM)

Oil-based muds (OBMs) are a type of drilling fluid or drilling mud commonly used in the oil and gas industry during drilling operations. Unlike water-based muds (WBMs), which use water as the primary base fluid, OBMs use various types of oil, typically mineral oil or synthetic oil, as the base fluid. These oil-based drilling fluids offer unique advantages and are used in specific drilling situations.

Water-Based-Muds (WBM)

Water-based muds (WBM) are a type of drilling fluid used in the oil and gas industry during drilling operations. They are the most commonly used drilling fluids and consist primarily of water as the base fluid, with various additives and chemicals to enhance their performance.

Synthetic-Based-Muds (SBM)

Synthetic-based muds (SBM) are a specialized type of drilling fluid used in the oil and gas industry during drilling operations. Unlike water-based muds (WBM) and oil-based muds (OBM), SBMs use synthetic hydrocarbon fluids as the base fluid. These synthetic fluids offer a unique set of advantages, making SBMs suitable for specific drilling challenges.

Functions of Drilling Fluid Loss Control (FLC)

• Remove cuttings from the well.
• Control formation pressure.
• Suspend and release cuttings.
• Seal permeable formations.
• Maintain wellbore stability.
• Minimize reservoir damage.
• Cool, lubricate, and support the bit and drilling assembly.

Benefits of Gilsonite in Drilling Fluid

• Reduced Injuries and Illnesses: A safer workplace results in fewer injuries and illnesses, leading to lower healthcare costs and reduced absenteeism.
• Improved Productivity: Safe work environments are more efficient, with fewer disruptions due to accidents or injuries.
• Enhanced Reputation: A commitment to health and safety enhances an organization’s reputation, attracting and retaining both employees and customers.
• Legal Compliance: Compliance with health and safety regulations mitigates legal and financial risks.
• Cost Savings: Preventing accidents and injuries reduces workers’ compensation and insurance costs.

Health and Safety of Gilsonite in Drilling Fluid

• Material Safety Data Sheet (MSDS): Organizations need to have access to the Material Safety Data Sheet (MSDS) for Gilsonite. The MSDS provides critical information on the chemical composition, potential hazards, safe handling, storage requirements, and emergency response procedures associated with Gilsonite. Employees should be trained in interpreting and following the guidelines outlined in the MSDS.
• Personal Protective Equipment (PPE): Workers involved in handling or working with Gilsonite in drilling fluids should wear appropriate personal protective equipment. This may include gloves, safety goggles, respirators, coveralls, and steel-toed boots, depending on the specific tasks and potential exposure levels.
• Inhalation Risks: Inhalation of Gilsonite dust can pose respiratory health risks. To mitigate this, workers should be educated about the risks of inhalation and provided with appropriate respiratory protection if necessary.
• Regulatory Compliance: Employers must ensure that their use of Gilsonite in drilling fluids complies with all relevant health and safety regulations, including those related to hazardous materials, workplace safety, and environmental protection.

Specification of gilsonite Drilling Fluid Loss Control