01/07/2026
VOC Filter & PV Valves for Bitumen Storage Tanks:
Bitumen is a highly viscous, black, and sticky form of petroleum that is left over from the fractional distillation of crude oil. It is primarily used in road construction as a binder for asphalt and in waterproofing products. Bitumen is typically stored at temperatures between 140 °C and 160 °C. This range provides the ideal viscosity to keep the material liquid and pumpable without risking localized overheating or degrading the product.
Bitumen can undergo wax crystallization at low or improper storage temperatures, and its heavy, condensed vapours frequently block Pressure-Vacuum (PV) valves on storage tanks. The exact crystallization temperature varies greatly depending on the bitumen's crude source, but it generally takes place across a broad range between +80 °C and +30 °C during cooling.
Oxidation and crystallization are fundamentally different chemical and physical processes. Oxidation changes a substance's chemical composition (via electron loss), while crystallization organizes a substance into a repeating, structured physical shape.
1. The Technical solution
Our VOC Filter design is back more than 25 years, HFO and TAR, but it was very isolated from project to project, and all was filed with no further attention to the environment.
Then some 15 years ago, due to residential areas were coming closer to tank storage facilities, we were met with an increased interest globally to prevent Odor / Smell from these facilities.
Recent years we have met local EPA (Environmental Protection Agencies) with focus on emission control from storage tanks, not covered under the EU VOC Directive, as a local issue to be addressed.
