The invention relates to a method for acquiring a denitrified
carbon source, particularly a method for acquiring a denitrified
carbon source by fermenting surplus
sludge. The method comprises the following steps: 1. carrying out ultrasonic pretreatment on surplus
sludge, and fermenting; and 2. aerating the supernatant generated after
fermentation, and treating the supernatant by a
guano process, wherein
effluent water of a reaction tank is the denitrified
carbon source acquired by fermenting surplus
sludge. The
raw material adopted by the method is waste in
municipal sewage plants, and therefore, the invention achieves the purpose of changing waste into resources; sludge generated in the
sewage plants is treated on the spot to produce a carbon source, thereby saving the transportation expenses; surplus sludge after
fermentation is converted into harmless substances, the amount of the sludge is reduced, and the surplus sludge can be further composted or fermented to produce
methane or can be landfilled, thereby facilitating the subsequent treatment and lowering the cost; when being used as a carbon source, the generated sludge supernatant has the advantages of high content of short chain fatty acids and high C / N ratio; and the
effluent water of the reaction tank can be directly transmitted into a
denitrification reaction tank and used as a carbon source.