Description and benefit of Gilsonite as fluid loss control additives in oil drilling fluid systems
Fluid loss control additives like Gilsonite powder help in water base and oil base drilling to:
1. Controls fluid loss and seepage
2. Stabilizes shales
3. Prevents lost circulation
4. Strengthens the wellbore to increase wellbore stability
5. Minimizes differential sticking
6. Promotes effective filter cake development
7. Performs in oil- and water-based drilling muds
8. Performs in HP/HT environments
9. Minimizes HSE risks
Properties of fluid loss control additives with Gilsonite
The unique properties of Gilsonite such as low specific gravity, particle-size distribution, impermeability, resistance to corrosive fluids, chemical inertness, and low water requirements result in a slurry having exceptional bridging properties, low slurry weight, compatibility with other slurry additives, and relatively high compressive strength when compared to other slurries of the same weight.Drilling fluid loss additives control component appears to be particularly important to fluid loss control and to act as a shale inhibitor.
Viscosity of fluid loss control additives
This fluid loss control additives by itself would tend to cause an increase in fluid viscosity but this is effectively dealt with by the other components which make up the additive of the invention.
The fluid loss control containing filtrate loss control fluids and chemical drilling mud additives, namely, containing filtrate loss control fluids for use in the oil and gas well drilling industry.
Reaction of fluid loss control additives in water
As indicated earlier, the additive of the invention comprises the product obtained by reacting together in the presence of water, quebracho, lignite, fluid loss control additive, sodium sulfite, paraformaldehyde and sodium hydroxide. Each of the indicated components is essential to obtain optimum results according to the invention.
The reaction conditions used to make the product of the invention can be fairly widely varied. Usually, however, the product is prepared by heating the indicated components in a sealed reaction vessel at a temperature in the order of 100 to 150C. for a period of 120 to 30 minutes, it being appreciated that shorter times can be used as the temperature is increased.
It appears that the reaction results in sulphomethylation and caustization of a complex formed between the quebracho, lignite and asphaltite although the chemistry involved is highly complex and not fully understood. In any case, the resulting composition, which is essentially water-soluble, is preferably dried and may be stored for subsequent blending with conventional clay-based aqueous drilling dispersions or drilling fluids. This blending advantageously is carried out on site although it will be appreciated that the additive may be pre-packed with the drilling fluid.
FLC in oil well drilling fluid systems
Typically the Gilsonite is fluid loss control additive that available in Turkey in rock form and pulverize to 200 mesh. The natural asphalt has flash point of 380C. and a softening point of minimum 205C. This asphaltite using by our customers worldwide in SLB, Scomi, Halliburton.
Use of Gilsonite in lost circulation
Gilsonite as fluid loss control additives has been added to drilling fluids to give better stability of well walls, to lubricate the drill string in a well, to seal micro-fractures and thus prevent the formation of larger fractures and to decrease the loss of filtrate to formations at high temperatures.
The use of FLC in drilling fluid dispersions or muds, to coat the walls of well holes, is an old and well-established procedure. The purpose of the fluid is to stabilize the walls of the hole by forming a relatively thin but strongly adherent coating or cake on the walls. The coating must be able to withstand relatively high temperatures and it should be resistant to the passage of moisture or fluid there through.
Fluid loss additives system advantage
- Provides superior shale stabilization
- Prevents differential sticking
- Reduces or eliminates lost circulation
- Provides wellbore strengthening matrix
Packing of FLC lump and powder form
In lump form like rock packed in 500~1000kg jumbo bag
200 mesh packed in 500~1000kg jumbo bag
Drilling fluid additive 300 mesh packed in 500~1000kg jumbo bag
30-40 mesh packed in 500~1000kg jumbo bag
100 mesh packed in 500~1000kg jumbo bag
300 mesh packed in 25kg pp bag
200 mesh packed 25kg multi paper bag
200 mesh packed 50lbs multi paper bag
Drilling fluid additive 30-40 mesh packed pp bag on pallet
Bulk on vessel
Specification of FLC
More pure gilsonite powder help better performance in fluid loss control.
SOLUBILITY IS CS2,WT%
SPECIFIC GRAVITY @25 C
NORMAL HEPTHAN INSOLUBLES,WT%
COLOR IS MASS
COLOR IN STREAK OR POWDER