Anti-blocking back flushing type sampling device for denitration CEMS (continuous emission monitoring system)

The embodiment of the utility model discloses an anti-blocking blowback type sampling device for a denitration CEMS system, which comprises a box body, a sampling probe is arranged in the box body, the sampling probe is connected with a three-way solenoid valve, the front end of the three-way solenoid valve is provided with a time relay, one side of the three-way solenoid valve is connected with a sampling line pipe, and the other side of the three-way solenoid valve is connected with a water pipe. And the other side of the three-way electromagnetic valve is connected with a compressed air pipe. Through the design, the device solves the problems that the existing back flushing effect is poor, and a probe filter element is often blocked; meanwhile, compared with other products with reverse blowing devices, only a reverse blowing electromagnetic valve is additionally arranged, reverse blowing air can be conveyed to a pretreatment cabinet through a sampling pipeline during reverse blowing, reverse blowing time n