Urea pyrolysis system and urea pyrolysis method

The invention discloses a urea pyrolysis system. The system comprises a boiler, a high-temperature dust removal device and a pyrolyzing furnace. A low-temperature super-heater and an economizer arranged below the low-temperature super-heater are arranged in the boiler, a flue gas outlet is formed in a flue between the low-temperature super-heater and the economizer, the high-temperature dust removal device is connected with the flue gas outlet, and the high-temperature dust removal device is connected with the pyrolyzing furnace through a transition flue. The system is simple in structure, theflue gas outlet is formed in the flue between the low-temperature super-heater and the economizer, high-temperature flue gas is led out through the flue gas outlet, and the high-temperature flue gasis conveyed to the pyrolyzing furnace after being subjected to a dust removal treatment by the high-temperature dust removal device and is applied for urea pyrolysis. An electric heater with high power consumption in an existi