Production Process of Oxidized Bitumen Intro
Oxidized bitumen, otherwise termed blown bitumen, is produced through a controlled oxidation process in which air is blown through hot bitumen under predetermined conditions. The process changes certain physical and chemical properties of bitumen, turning it harder, elastic, and useful for specialized applications. An overview of the production process is as follows:
Raw Material Selection
Therefore, raw material selection is a very critical and first step in the production of oxidized bitumen. This is choosing a suitable grade of raw bitumen, normally taken as a residue from fractional distillation of crude oil at refineries.
The selected bitumen is to have appropriate viscosity, penetration, and chemical composition in order to react optimally during the oxidation process. Since the properties of the final product-hardness, elasticity, thermal resistance-depends directly on the quality of the raw material, a careful evaluation-selection must be made to get desired performances in the end-use applications.
Heating of Bitumen
Heating of Bitumen is one of the crucial stages in the process of the manufacture of oxidized bitumen. Raw bitumen is heated up to a molten state in order to prepare it for oxidation. In most cases, bitumen is heated within the reactor or furnace to attain a temperature of around 240°C to 320°C, depending on the specifications of the product that has to be yielded.
High temperature reduces the viscosity of the bitumen, allowing it to flow freely, with the result of uniform exposure in the subsequent air-blowing process. Heating up should be just at the appropriate degree to avoid thermal degradation or overheating, which may badly affect the quality of the finished product.
Air Blowing Process
The process involves blowing air from an air blower to a reactor at a flow rate of 85-140 m3/min, with a temperature range of 215-260 °C. The reactor uses baffles or agitation systems to mix bitumen with air. The process stiffens bitumen, causing changes in its softening point, penetration value, and viscosity.
High temperature causes heat production, so the reactor should be covered with a water jacket or a water spray facility. Off-gas, containing oxygen, can explode if not controlled.
Control of Reaction Parameters
Control of the reaction parameters is one very important step in the process of oxidizing bitumen to come up with a material whose properties are consistent with those desired. Key parameters, including air flow rate, reaction temperature, and the time taken in the reaction course, are stringently watched and controlled. Typically, air is blown into the heated bitumen at controlled rates to allow oxygen to react with hydrocarbon atoms; this reaction changes the molecular structure of bitumen.
Temperature is kept between 240°C and 320°C to ensure that there is enough oxidation without overheating. Modifications of these parameters will allow the design of the bitumen characteristics, which can be from hardness and softening point to elasticity. This processing step is important for product quality achievement with specific application requirements.
Cooling and Storage
Cooling and Storage is the last stage of the oxidized bitumen production process, during which the processed bitumen is brought down to a temperature at which it can be handled easily and prepared for storage or packaging. Once the oxidation reaction is finished, the hot bitumen is cooled slowly to avoid thermal shock in order to keep its enhanced properties.
It is usually done by circulating water or air around the product in especially designed cooling systems. In this condition, the bitumen will be moved either to storage tanks or to molds, where it will be cooled and solidified. Oxidized bitumen could be packed in drums, moved in bulk, or even block-shaped, depending on different requirements at its end-use, hence ready to be delivered to the industries.
Quality Control
The final product is put through intense testing to ensure that the industry standards and specifications required are met, including, among others, penetration grade, softening point, and viscosity.
Conclusion
It is in this regard that the production process of oxidized bitumen transforms raw bitumen into a flexible and durable material suitable for these industrial uses.
The appropriate control of the oxidation process will provide the manufacturer with a bitumen product having increased hardness, elasticity, and thermal stability for applications in waterproofing, roofing, pipe coating, and among others.
This flexible and highly efficient production process ensures high-quality output to meet the ever-increasing demand for dependable materials in both building and manufacturing industries. Further properties can be tailored with this process, thus making it an important one for meeting diversified industry requirements.
