Gasification flash evaporation system capable of automatically cleaning condenser on line

The invention provides a gasification flash evaporation system capable of automatically cleaning a condenser on line. The gasification flash evaporation system comprises a first condenser, a second condenser, a first blowback system, a second blowback system, a gas-liquid separation tank, a blowback buffer tank, a low-pressure flash evaporation tank, a low-pressure circulating water pump, a watercooler and a controller, the gasification flash evaporation system achieves on-line intelligent work, automatic switching, automatic putting into use and automatic cleaning, solves the problems that the flash evaporation condenser is short in on-line operation time, flash steam heat cannot be effectively utilized after the condenser is blocked is reduced, the temperature of high-pressure circulating water is reduced (the temperature of synthesis gas washing water is low), and the problems of low water vapor content at the outlet of the synthesis gas washing tower and high conversion energy consumption are solved; and the problems that after the flash evaporation condenser is blocked, heat moves backwards, the pressure of a cooler is large, and a downstream sulfur recovery device or a torchdevice cannot normally put into use are solved.