Properties of phosphogypsum as technogenic soil

Autor: A. L. Nevzorov, A. M. Shiranov, Yu V. Saenko
Rok vydání: 2020
Předmět:
Zdroj: IOP Conference Series: Materials Science and Engineering. 945:012067
ISSN: 1757-899X
1757-8981
Popis: Phosphogypsum (CaSO4·2H2O) is heavy tonnage waste generated by binding calcium in the process of sulfuric acid decomposition of phosphate raw materials when obtaining wet-process phosphoric acid in the production of phosphate fertilizers. In appearance, it is solid fine-crystalline substance of white or gray color with inclusions of large aggregates. The paper presents the results of laboratory studies of more than 390 samples of phosphogypsum neutralized with construction lime. The deformation and strength properties as well as the water permeability were determined on specially prepared samples with the relative compaction of 0.95, 0.90 and 0.80 by methods used in engineering and geological surveys. While the angle of internal friction, the cohesion and the coefficient of permeability of the phosphogypsum have the values typical for fine or silty sands, the compressibility characteristics are significantly worse due to the solubility of the particles. Phosphogypsum is characterized by subsidence and suffusion settling, which are proper for carbonate rocks (dolomite, limestone). The use of the phosphogypsum as ground is possible for subbase of roads with low traffic intensity with a gravel pavement, for dams at industrial solid waste storage facilities, as well as for engineering reclamation of those storage facilities, but only if implementing water protection measures.
Databáze: OpenAIRE