Due to the climate change, the increased occurrence of typhoon results in high turbidity source water exceeds 10,000 NTU during storm season and the water treatment plants have to shut down. Magnetic seeding aggregation (MSA) of high turbid water using magnetite nanoparticles is studied as a pretreatment process before water intake. The influences of dosage of magnetite nanoparticles, solution pH, applied magnetic field strength during settling and total organic carbon (TOC) concentration on the removal of turbidity were investigated. The results showed that with 1 g L−1 magnetite nanoparticles, the turbidity can effectively reduced from about 10,000 to less than 1,000 NTU, which is acceptable for potable water treatment plant. The zeta potential of clay and magnetite cannot explain the influences of solution pH on MSA of high turbid water because of the presence of TOC. The dissociation and configuration of adsorbed humic acid also affect the removal or turbidity by MSA at different solution pHs. MSA of turbid water of kaolin showed that low concentration of TOC helped the removal of turbidity by bridging while high concentration of TOC introduced steric repulsion between particles. When a magnetic field was applied during the settling of magnetic aggregates, the turbidity dropped dramatically to about 100 NTU.
|Number of pages||6|
|Journal||Sustainable Environment Research|
|State||Published - 2010|
- High turbid water
- Magnetic seeding aggregation (MSA)
- Magnetite nanoparticles