The invention discloses a method for treating waste pollutants in a pig farm. The method comprises the following steps of: A, performing
anaerobic treatment on a
biogas generating pit, namely building the
biogas generating pit, performing
anaerobic treatment on waste pollutants, which enter the
biogas generating pit, in the pig farm, and killing parasites and pathogenic microorganisms through anaerobic
fermentation, wherein the
chemical oxygen demand (COD) content is reduced, and the
normal growth of aquatic plants in a wet land is facilitated; B, performing primary ecological wet
land treatment, namely planting green watermifoil, growing the green watermifoil, absorbing
nitrogen and
phosphorus, harvesting the watermifoil as materials covering a tea
yard and a fruit
yard; C, treating secondary wet
land treatment, namely planting perennial bengal waterdropwort
herb in winter, planting aquatic water
spinach in summer, and harvesting the water
spinach and the perennial bengal waterdropwort
herb from the wet land each year; D, treating a
tertiary economical wet land, namely planting perennial bengal waterdropwort
herb in windter, planting
lotus root in summer, putting natural crucians into the wet land, and harvesting the
lotus root, the bengal waterdropwort herb and water products from the wet land each year. The construction cost and the running cost are low; the method is easy to operate; the
nitrogen, the
phosphorus and the COD (
Chemical Oxygen Demand) in the waste in the pig farm can be greatly treated; and the method is
extremely good in popularization and application prospect.