Exploring the World of Asphalt and the Marvels of Gilsonite
Asphalt, also known as bitumen, is a versatile and indispensable material in the construction industry. Its origins can be traced back to natural deposits or refined products, classified as Gilsonite or pitch. Before the 20th century, the term Asphaltum was commonly used, with its etymology rooted in Ancient Greek. The largest natural deposit of asphalt worldwide, estimated at 10 million tons, underscores its global significance.
The predominant use of asphalt, constituting 70% of its applications, is in road construction. It serves as the binding agent, or glue, when mixed with aggregate particles, resulting in the formation of asphalt concrete. Beyond road construction, it finds extensive use in bituminous waterproofing products such as roofing felt, and for sealing flat roofs. The terms “asphalt” and “bitumen” are often used interchangeably in material sciences and engineering, encompassing both natural and manufactured forms. Geologists globally tend to favor the term “bitumen” for naturally occurring material, while “bitumen” is the prevalent term for the manufactured material obtained through the distillation process of selected crude oils.
Naturally occurring bitumen, sometimes referred to as “crude bitumen or Gilsonite,” exhibits a viscosity similar to cold molasses. In contrast, material obtained from the fractional distillation of crude oil, boiling at 525 °C (977 °F), is termed “refined bitumen.” Its properties dynamically change with temperature, influencing viscosity and, consequently, compaction during the construction process. Computer simulations of simplified model systems have proven effective in reproducing some of bitumen’s characteristic properties.
The Role of Gilsonite in Asphalt:
Gilsonite, often in the form of a powder bitumen sealer, plays a crucial role in enhancing its properties. Its economical and reasonable use in driveway construction has been supported by high-level tension tests, including indirect tension tests, freezing tensile stress, and expansion and fracture tension. Results from periodic measurements and comparisons of bitumen surfaces using Gilsonite, monitored by specialized computer software from the US Federal Highway Administration, have demonstrated a remarkable increase in asphalt life from an average of 18 to 29 years.
In various applications, such as tolls, airport runways, highway exits, loading terminals, U-turns, installations, intersections, bus stations, bus lanes, loading docks, parking lots, and squares, Gilsonite is employed for its resistance to deformation under pressure. Furthermore, the use of Gilsonite in these scenarios has shown an increase in the passing loads at low or static speeds. Gilsonite’s effectiveness extends to making surfaces more resistant to shear forces in areas such as runways, highways, and racetracks that face heavy traffic or high speeds. It can be applied to all types of pavement asphalt, including mastic asphalt, cement asphalt, smooth asphalt, and ordinary bituminous asphalt.
One notable advantage of Gilsonite is its ability to improve the properties of asphalt at high temperatures by enhancing component adhesiveness. As a result, the composition exhibits more hardness at higher temperatures and experiences less phase change. Gilsonite is widely utilized in recycling asphalts, with applications extending to a remarkable 50%.
Advantages of Using Gilsonite in Asphalt:
The incorporation of Gilsonite into bitumen offers several notable advantages:
Elimination of the Need for Other Polymer Modifiers: When Gilsonite is used in bitumen, there is no requirement for additional polymer modifiers to modify the bitumen.
Enhanced Stability and Resistance: Bitumen modified by Gilsonite demonstrates higher stability, less deformation, and increased resistance against low temperatures.
Increased Load-Bearing Capacity: The addition of Gilsonite results in an increase in the load-bearing capacity of bitumen.
Optimal Ratio of Gilsonite: Bitumen modified by Gilsonite requires the lowest ratio of the substance compared to other modifiers.
Reduction in Bitumen Penetration: Gilsonite helps reduce the degree of bitumen penetration.
Higher Softening Temperature: The incorporation of Gilsonite increases the softening temperature of bitumen.
Improved Viscosity: Bitumen modified with Gilsonite exhibits increased viscosity of Brookfield bitumen.
These advantages collectively contribute to the overall durability, longevity, and performance of bitumen in various applications.
Advantages of Gilsonite Beyond Asphalt:
Gilsonite’s applications extend beyond bitumen to a diverse range of industries, showcasing its versatility and utility:
Construction Industry: Gilsonite, in powder form, is utilized in various construction applications due to its ability to dissolve completely in bitumen, forming close molecular bonds. Its use in driveways enhances resistance to deformation, weather conditions, and high temperatures. It reduces road thickness and insulates seams and sidewalks.
Cost-Effective Solutions: Gilsonite’s application in asphalt repair or replacement proves cost–effective, reducing the overall expenditure in maintaining bitumen surfaces.
Crack Prevention: The incorporation of Gilsonite reduces the likelihood of cracks in cold weather at low temperatures, contributing to the structural integrity of the surface.
Traffic–Heavy Areas: Gilsonite’s adhesive properties and durability make it advantageous in areas with high traffic, ensuring long–lasting and reliable performance.
Insulation and Protective Coatings: Gilsonite is utilized as an additive in the rust and epoxy industry, serving as primers, anti–corrosion paint, wood paints, and pipe coverings. It stabilizes color against harmful UV sunlight in paints.
Insulation in Various Applications: Gilsonite is used to insulate water tanks with bitumen–based paints, insulate fishing boats, and protect walls.
Printing Industry: In the toner printer and inkjet industries, Gilsonite serves as an adhesion agent, ensuring high–quality, pure black prints on newspapers and magazines.
These diverse applications showcase the extensive utility of Gilsonite across various industries, highlighting its role as a versatile and effective material.
Innovations in Asphalt Cement with Gilsonite:
Research has uncovered innovative uses of Gilsonite in enhancing asphalt cement. Asphalt cement, when toughened with natural bitumen and thinned with reactive oil, can yield beneficial results. Reactive oil, characterized by a high content of unsaturated fatty acids, cures or reacts after the application of asphalt cement to the highway. This curing process allows for lower viscosity application, preventing rutting and ensuring a more durable and resilient road surface.
Gilsonite, with a preferable melting or softening point of about 148 ºC (300 °F), facilitates easy softening and blending with petroleum asphalt at such temperatures. The composition of asphalt cement typically consists of 100 parts by weight of petroleum asphalt, 1 to 10 parts by weight of natural bitumen, 1 to 10 parts by weight of a thinning reactive oil with at least a 60% unsaturated fatty acid content (having 14 to 24 carbon atoms), and 1 to 10 parts by weight of an elastomer.
Packing of Natural Bitumen Lump and Powder Micronized form:
■ Gilsonite in Lump form like rock packed in the 500 – 1000/Kg. Jumbo Bag
■ Gilsonite 200 Mesh packed in the 500 – 1000/Kg. Jumbo Bag
■ Gilsonite 300 Mesh packed in the 500 – 1000/Kg. Jumbo Bag
■ Gilsonite 30 – 40 Mesh packed in the 500 – 1000/Kg. Jumbo Bag
■ Gilsonite 100 Mesh packed in the 500 – 1000/Kg. Jumbo Bag
■ Gilsonite 300 Mesh packed in the 25/Kg. PP Bag
■ Gilsonite 200 Mesh packed 25/Kg. Multi–Paper Bag
■ Gilsonite 200 Mesh packed 50/lbs Multi–Paper Bag