Method for purifying and rejuvenating Taiping No.3 earthworm

The invention discloses a method for purifying and rejuvenating Taiping No.3 earthworm, which comprises the following steps: (1), separating earthworm species from a substrate containing earthworm cocoons after 12 to 18 days when the earthworm species produce cocoons in a cultivating box; (2), mixed culturing the earthworms for 2 to 5 days in a high-density environment; (3), allocating the earthworms in the cultivating box to reduce the density of the earthworm species so that earthworm species are hybridized; (4), placing the earthworms in the cultivating box and adding a new substrate to produce the earthworms continuously; (5), mixing and incubating the earthworm cocoons in an amount of more than 50 boxes, and keeping the temperature of the substrate to be between 20 and 23 DEG C; and (6), after incubating the earthworm cocoons, dispersing the earthworms once per 10 to15 days, keeping 40 to 60 thousand of the earthworms per square meter, adding the new substrate, feeding the earthworms once per 2 to 4 days