Oil removal pretreatment method for oil-containing organic wastewater

The invention discloses an oil removal pretreatment method for oil-containing organic wastewater. The method comprises the following steps: a, taking residual sludge generated by a biochemical system as a flocculation source of air floatation, and mixing the residual sludge with the oil-containing organic wastewater to generate air floatation; b, firstly mixing the oil-containing organic wastewater with residual sludge generated by a biochemical system, then adding a flocculating agent to enable the residual sludge to generate flocs, and adsorbing grease in the wastewater by utilizing the flocs generated by flocculation to realize oil removal pretreatment of the oil-containing organic wastewater; and c, carrying out biochemical treatment on the wastewater subjected to oil removal pretreatment to remove organic matters in the wastewater so as to generate residual sludge. According to the method, the dosage of a chemical flocculant is reduced; the biological adsorbability of the biochemical sludge is utilized t