Abstract
The removal of algae was conducted by loess, aluminum sulfate and PAC on a laboratory scale. The loess was consists of organic matter 1.4%, T-N $289{\mu}g/g$, T-P $17{\mu}g/g$, $Al841.2{\mu} g/g$, Fe $592.7{\mu}g/g$, Ca $10.6{\mu}g/g$, Mg $85.5{\mu}g/g$ and Mn $6.6{\mu}g/g$. Test water was dominated by Microcystis aeruginosa. When test water was mixed with 0.01, 0.05. and 0.1 g/$\ell$ of the loess in 5 minutes, after settled in 1 hour, the removal of chl-a was 2, 22, and 36% respectively. The removal of chl-a was 69%, 70% in pH 4.5 and 9.0 and above 92% between pH 5.0 and 8.0 after the $2mg/{\ell}$ of aluminum sulfate was added. When the $2mg/{\ell}$ of PAC and $0.05g/{\ell}$ of loess were added to test water together, the removal of chl-a was 95-99% in pH 4.0-8.0, 60% in pH 9.0, and 18% in pH 10.0. The removal of chl-a was higher when loess, aluminum sulfate and PAC was used together than used alone.