Gilsonite , to be asphaltum is a natural resinous hydrocarbon found in natural as a mineral . This natural asphalt is similar to hard petroleum asphalt and is often called natural asphalt , asphaltite , uintaite or asphaltum . Gilsonite is soluble in aromatic and aliphatic solvents as well as petroleum asphalt . Due to its unique compatibility , gilsonite Is frequently used to harden softer oetroleum products . Gilsonite mass is a shiny , black substance similar in appearance to the mineral obsidian . It si brittle and can be easily crushed into dark brown powder.
Gilsonite is found below earths surface in vertical veins or seams that are generally between two and six feet in width , but can be as wide as 28 feet . The veins are nearly parallel to each other and are oriented in northwest to southeast direction . They extend Many miles in lenth and as deep as 1500 feet .The vein will show up on the surface as athin outcopping and gradually widen as it goes deeper . Due to its narrow mining face , Gilsonite is mined today , much like it was 50 or 100 years ago .
The primary difference is that modern miners use pneumatic chipping hammers and mechanical hoists
Physical Properties:
| Test | Test Result | Method |
|---|---|---|
| Color in Mass | ---- | Black |
| Color in streak or Powder | ---- | Brown |
| Specific Gravity at 25/25 C | ASTM-D3289 | 0.8 |
| ASH content, wt% | ASTM-D3147 | 7.6 |
| Moisture content wt% | ASTM-D3173 | 0.5 |
| Volatile matter at 900C | ASTM-D3175 | 62.3 |
| Solubility in cs 2 wt% | ASTM-D4 | 74.9 |
| Softening point C | ASTM-D-36 | 160 |
| Penetration | ---- | 3 |
| Flash point | ---- | 380-400 F |
| Fixed carbon | ASTM-D3172 | 27.5 |
| Elemental analysis: | ASTM-D5291 | 0.59 |
| N content , wt% | ASTM-D5291 | 74.4 |
| C content , wt% | ASTM-D5291 | 7.3 |
| H content , wt% | Lp-242 | 4.5 |
| S content , wt% | ---- | ---- |
Cement Addetive for Oil Drilling
Since Gilsonite, a solid hydrocarbon, was introduced to the oil industry in August 1957 as a cement additive, several thousands of jobs have been performed using the material. These operations have included primary cementing through lost-circulation zones of surface, intermediate, and production pipe in both single and multiple stages as well as various remedial jobs such as squeezing, re-cementing above inadequate fill-up, and plugging back to reestablish drilling-fluid circulation. Designed primarily as a combination low-density lost-circulation slurry, Gilsonite has yielded excellent results in areas of incompetent formations as well as in other types of lost-circulation zones. Field results generally show that fill-up of 80 to 90 percent can be obtained in areas where only 50 to 60 percent fill-up was possible with other types of slurries.
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.
Asphalt Mixes and Road Construction
Gilsonite is used as a performance-enhancing agent for asphalt mixes. Gilsonite-modified paving mixes achieve higher PG grades and incorporate perfectly into the asphalt blend with no need for high shear milling as is the case with many other modifiers. Gilsonite-modified asphalts have higher stability, reduced deformation, reduced temperature susceptibility and increased resistance to water stripping than non-modified asphalts. Gilsonite is also used to make both solvent-based and emulsion pavement sealers with superior appearance and weathering properties.
Foundry Sector
Gilsonite is combined with coal and other ingredients as an additive in foundry sands to insure the quality of the molded part by improving mold release and the overall finish of metal castings.
Chemical Products Sector
Gilsonite combines with many other chemicals and materials that take advantage of its unique physical and chemical properties. Binder and coating applications in metallurgical, wood product, refractary and other industries further demonstrate the versatility and usefulness of this remarkable material.
Inks and Paints Sector
Iranian Gilsonite Resin is widely used as the primary carbon black wetting agent for black news inks and headset and gravure inks. Iranian Gilsonite Resin competes advantageously with petroleum-based hydrocarbon resins, phenolic resins and metal resinates, all of which it can complement or replace to various degrees. Various concentrations of Iranian Gilsonite Resin are used to manufacture law-rub-off news inks with superior gloss and tack properties. Special grades of Gilsonite called Selects are also standard ingredients in black ink formulations and are used as additives in asphaltic paints and varnishes.