Method for Producing Bitumen 60/70 Compositions
Bitumen 60/70 stands as a preferred choice for road construction in moderate to hot climates. Engineers rely on this grade for its balanced penetration and thermal stability. In this article, we walk you through the essential steps in producing bitumen 60/70 compositions — from crude selection to packaging and export readiness.
1. Choosing the Right Crude Oil
Refineries begin by selecting heavy crude oil with a high asphaltene content. This type of crude naturally supports the viscosity and elasticity required for bitumen 60/70. Therefore, the initial feedstock selection directly influences the final quality.
2. Atmospheric and Vacuum Distillation
Refinery technicians first separate lighter fractions such as gasoline, kerosene, and diesel through atmospheric distillation. After that, they send the heavier residue to vacuum distillation units. This step isolates the bitumen-rich bottom material necessary for penetration-grade products like bitumen 60/70.
3. Avoiding Air Blowing for This Grade
While air blowing enhances oxidation and hardness, producers usually avoid it when making bitumen 60/70. This technique is more relevant in manufacturing oxidized grades such as bitumen 85/25 or bitumen 115/15.
4. Settling and Storage in Heated Tanks
Once distillation is complete, operators store the bitumen in heated steel tanks. They maintain the temperature around 160–180°C to prevent solidification and preserve pumpability. Moreover, continuous stirring helps avoid sediment accumulation and ensures consistent quality.
5. Quality Testing in the Laboratory
Laboratories run a full suite of tests to verify compliance with ASTM standards. For instance, bitumen 60/70 must show a penetration value between 60 and 70 dmm at 25°C (ASTM D5) and a softening point between 48–56°C (ASTM D36). In addition, technicians measure viscosity, ductility, and flash point to confirm performance under field conditions.
6. Packaging and Export Preparation
Once approved, the bitumen moves to packaging stations. Depending on client requirements, teams fill it into 180 kg drums, 1-ton jumbo bags, or load it directly into heated tankers. As a result, exporters can ship bitumen 60/70 efficiently via sea or land routes, especially through ports like Bandar Abbas.
Conclusion
Producing bitumen 60/70 requires precision, technical expertise, and strict process control. Each phase — from crude selection to final testing — plays a vital role in delivering a consistent, high-quality product. Consequently, many road construction firms and international buyers continue to depend on this grade for reliable results.