Asphalt powder is a specially treated asphalt product, and its processing process mainly includes the following steps:
1. Raw material preparation: select the appropriate asphalt raw materials, commonly used are petroleum asphalt and coal asphalt, etc. The quality of asphalt raw materials is required to be stable, with good fluidity and appropriate viscosity.
Pretreatment: Pretreatment of asphalt raw materials, such as dehydration, deslagging, etc., to improve the purity and quality of asphalt powder.
Sulfonation reaction: The pretreated bitumen is reacted with a sulfonating agent, such as sulfuric acid or sulfate, to produce sulfonated bitumen. During the sulfonation reaction, the hydrogen atoms on the aromatic ring in the bitumen are replaced by sulfonic acid groups to form sulfonates.
4. Emulsification treatment: The sulfonated asphalt is emulsified to make it an emulsion of oil-in-water (O w) or water-in-oil (W O). Emulsification can improve the stability and fluidity of asphalt powder.
5. High temperature stabilization treatment: The emulsified asphalt powder is subjected to high temperature stabilization treatment to improve its temperature resistance. This step is usually achieved by heating, stirring, etc.
6. Quality inspection and packaging: quality inspection of processed asphalt powder, including pH value, moisture, oil solubles, high temperature and high pressure filtration loss and other indicators. Qualified products are packaged, usually in 25kg bags.
Storage and transportation: Packaged asphalt powder should be stored in a dry and ventilated environment, away from direct sunlight and high temperatures. During transportation, the integrity and tightness of the packaging should be ensured to prevent moisture absorption.
To sum up, the processing process of asphalt powder mainly includes sulfonation reaction, emulsification treatment, high temperature stabilization treatment, quality testing and packaging, storage and transportation. Through these processing steps, asphalt powder products with excellent properties can be obtained, which are suitable for various drilling fluid systems.