The invention discloses a method for effectively controlling
algae bloom in eutrophic lakes and a
floating floor of a magnetic precipitating
machine; polymeric aluminum
ferric chloride,
ferric sulfate and ultrapure
magnetite powder are uniformly blended according to a certain weight proportion and are prepared into magnetic
algaecide by compounding and then the magnetic
algaecide, together with water, is prepared into suspension; the suspension is blended with flowing
algae-containing
lake water and then
algae is collected, precipitated and removed. The structure of the
floating floor of the magnetic precipitating
machine is as follows: the side surface of a boat
hull is connected with a fluidizing tank, the front end of the fluidizing tank is opened, flow baffles are arranged at the middle of the fluidizing tank in a staggered way, the area in front of the flow baffles is provided with a
mixing tank, while the area behind the flow baffles is provided with a
sewage collecting tank. The invention not only can effectively flocculate algae cells and granular
nitrogen-
phosphorus suspended matters in water, but also can transform water-soluble
phosphate radicals into slightly soluble
phosphate to be flocculated. The adoption of the
floating floor of the magnetic precipitating
machine can greatly shorten the precipitating time of floccus, can reduce the length of a subsider and improve treatment efficiency, thus being suitable for the treatment of the
eutrophic water body with large area.