Development of soil conditioner for reclaimed land desalinization based on high-iron fly ash

• Published in: Paddy and water environment 2022-04, Vol.20 (2), p.277-286
• Main Authors: Kim, Donggeun, Kim, Taejin, Jeon, Jihun, Son, Younghwan
• Format: Article
• Language: English
• Subjects: Additives; Admixtures; Agglomeration; Aggregation; Agriculture; Aluminum sulfate; Biomedical and Life Sciences; Blast furnace iron mixers; Blast furnace practice; Blast furnace slags; Calcium; Cationic polymerization; Cations; Desalination; Ecotoxicology; Fly ash; Geoecology/Natural Processes; Hydrogeology; Hydrology/Water Resources; Iron; Land reclamation; Life Sciences; Mixing ratio; Permeability; Polymers; Ready mixed concrete; Reclaimed land; Recycling; Slag; Slag cements; Soil; Soil conditioners; Soil conditions; Soil conservation; Soil improvement; Soil management; Soil permeability; Soil Science & Conservation; Soil structure; Soil water; Soils; Sulphates; Yard waste
• ISSN: 1611-2490; 1611-2504
• DOI: 10.1007/s10333-022-00893-8

Reclaimed soil is known to have high salinity due to poor water permeability. Soil conditioner can improve the permeability of the ground by changing the composition or structure of the soil, and various materials can be used. Fly ash is mainly recycled as a ready-mixed concrete admixture. However, the high Fe content fly ash limits its recycling due to esthetic problems, so a new recycling plan is needed. Calcium in fly ash can support soil aggregation, but its lower content than that of a general soil conditioner requires additional measures. Therefore, in this study, a new soil conditioner based on high Fe content fly ash with low recycling rate was developed and applied to improve soil in reclaimed land. Three soil conditioners based on fly ash, blast furnace slag cement, CaSO 4 , Al 2 (SO 4 ) 3 , and cationic polymer were developed. The soil conditioners increased soil aggregation size and permeability. This improvement is greater in soils with higher fine content, higher additive content in soil conditioners, and a higher mixing ratio of soil conditioners. The rate of capillary rise increased, but the height of capillary rise is predicted to decrease based on particle size analysis. In conclusion, soil conditioner with high Fe content fly ash can be used to improve reclaimed soil. The new recycling method for high Fe content fly ash proposed in this study is expected to increase the recycling rate of fly ash.