General Definition of Gilsonite
Natural bitumen (also known as Gilsonite) was produced when crude oil was exerted high pressure and temperature for a period of millions of years. They are a is naturally-occurring mixture of bitumen and mineral matter formed by oil seepages in the earth’s crust. The first Gilsonite came from Caribbean country, Trinidad and Tobago with 55% hydrocarbon content and 45% minerals. Initially, they are used as an additive in road construction.
Generally Gilsonite is mineral hydrocarbon of asphaltite class which is a black solid of fairly bright luster and melts or fuses between 130 and 210C. It is soluble in carbon disulfide, carbon tetrachloride and many other non-polar organic solvent.
Gilsonite is very fragile and it shatters easily. Rolling the Gilsonite between two drums tends to give the best particle distribution to use as raw material in carbon production.
When we process the Gilsonite from chunks to powder and then heating the Gilsonite powder where we drive off the high value volatiles, we get much less material, then we are able to supply volume quantity to our customer.
Gilsonite is often used as an additive to the paving in heavy traffic area like junction or bus station. Due extreme cold or high temperature, heavy weight of trucks and extreme weather conditions, pavements are susceptible to deformations and cracks. Because of this, road construction companies are looking for new technology and material to use to reduce the crack and deformation problems. Bitumen Malaysia supplies Gilsonite in medium course and fine size and is mainly used as resistance against fatigue and deformation.
Gilsonite and modified Gilsonite supplied by Bitumen Malaysia are added directly at the production site of the asphalt and bitumen mixing plant. To use asphalt in road construction in cold weather just use our Gilsonite and no need to use any special bitumen. Another usage of Gilsonite is as a bitumen binder. Adding 13-14% Gilsonite can increase the performance of the asphalt.
Gilsonite can be used to lighten the slurry and increase the slurry yield but will still provide a relatively high-strength set cement. Large amounts of water are not required for Gilsonite. The reduction of slurry density is primarily the result of the low specific gravity of the Gilsonite.
The primary use for Gilsonite in oil well drilling project is as a lost circulation materials (LCM). Its effectiveness is due to the particle-size distribution. The larger and medium-size particles bridge forming a network which retains the finer particles. Thus, a dense deposit is formed which is sealed by the cement. Decreasing the slurry weight by using an extender helps in controlling lost circulation by reducing the hydrostatic pressure.
Gilsonite should be added slowly at the vortex. Provisions should be made to recirculate the hot bitumen through recirculation piping. The most important item is that the minimum temperature should be about 170-175°C. Anything significantly less than this will extend mixing time. For typical (5-10%) substitution concentrations, 2-4 hours of mixing after addition is completed should be sufficient. For master batch concentrations (over 10% mineral bitumen) recirculation overnight is preferred.