Device for recovering VOCs (Volatile Organic Compounds) in purification storage tank of coking plant

The invention belongs to the technical field of VOCs recovery of coking plants, and particularly relates to a device for recovering VOCs in a purification storage tank of a coking plant. Comprising a flushing pipe and a plurality of purification storage tanks, the air outlet ends of the purification storage tanks are jointly communicated with a U-shaped bent acid steam liquid discharging pipe, the acid steam liquid discharging pipe is sequentially communicated with an acid steam valve, a sight glass and a deacidification ammonia distillation storage tank, and the air outlet end of the upper portion of the deacidification ammonia distillation storage tank is sequentially connected with a positive and negative pressure breather valve, a first switching valve and a gas-liquid separation tank through a negative pressure main pipeline. The gas outlet end of the gas-liquid separation tank is sequentially connected with an extraction valve and an air fan through a fan front pipeline, and the liquid outlet end of the