Performance and application of PS slow-release algal inhibition materials based on modified fly ash and cement

Abstract

In this paper, a new type of slow-release algae control agent was prepared by using modified fly ash and cement as the base material and PS (potassium persulfate), an inorganic substance that dissolves algae by destroying their cellular structure, as the active component, and compounding the three in a certain proportion, and the finished product was obtained after 14 days of maintenance. The rate of release is primarily influenced by temperature, particle size, and load, while pH has minimal impact. Specifically, as the temperature increases from 4 °C to 40 °C, the rate of slow release increases from 0.74 mg/g/d to 1.35 mg/g/d. When particle size increased from 3 mm to 5 mm, the slow-release rate decreased from 1.06 mg/g/d to 0.70 mg/g/d. When the load increased from 10 mg/g to 30 mg/g, the slow-release rate also increased from 0.60 mg/g/d to 2.10 mg/g/d. In the algal inhibition experiment, the composite material was selected with a dose of 20 g/L, a loading capacity of 15 mg/g, and a particle size of 3 mm. After 14 days, algae removal rates, ammonia nitrogen, total phosphorus, and COD were found to be 96.55 %, 56.14 %, 78.2 %, and 86.81 %, respectively. The microstructure, elemental composition, and distribution of functional groups in the materials were analyzed using SEM, EDS, and FTIR. The algal suppressor was evenly distributed throughout the substrate surface. Additionally, there was a decrease in metal elements and an increase in hydroxyl groups. The experimental data show that the material is a slow-release algal inhibitor with good performance and practical application value.

Keywords

• Slow-release materials
• Persulfate
• Algal inhibition
• Nitrogen and phosphorus