NOVELTY - Recycling and pre-separating method of intermediate pressure system of urea comprises using a urea synthesizing tower, a pre-separator which is connected with urea synthesizing tower, a branched heater, a pre-distillation column, a secondary branched tower, an evaporator, a flash heat exchanger and a cold absorber. A lower end of the pre-separator is connected with upper end of pre-distillation column. The branched heater is connected with lower end of pre-distillation column. A bottom of pre-distillation column is connected with secondary branched tower.    USE - Recycling and pre-separating technical method of intermediate pressure system of urea.    ADVANTAGE - Synthesizing liquid in urea synthesizing tower contains ammonium carbamate, excess ammonia and water which need to be separated from urea in decompressing heating manner and recycled, thus the method not only saves a mass of steam, but also has benefits of saving energy and reducing emission.    DETAILED DESCRIPTION - Recycling and pre-separating method of intermediate pressure system of urea comprises using a urea synthesizing tower, a pre-separator which is connected with urea synthesizing tower, a branched heater, a pre-distillation column, a secondary branched tower, an evaporator, a flash heat exchanger and a cold absorber. A lower end of the pre-separator is connected with upper end of pre-distillation column. The branched heater is connected with lower end of pre-distillation column. A bottom of pre-distillation column is connected with secondary branched tower while upper end is connected with heat energy recovery section at lower end of the evaporator by pipeline. The heat energy recovery section of evaporator is connected with lower end of that of flash heat exchanger, and is connected with the cold absorber by pipeline. Upper end of the pre-separator is connected with pipeline of heat energy utilization section by another pipeline. Mutual connections of the components form an integral body.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic flow diagram of the recycling and pre-separating method of intermediate pressure system of urea (Drawing includes non-English language text).