Steam recycling system for pickling line drying fan

The steam recycling system comprises six heat exchangers and a trench, the six heat exchangers are of the same structure and are sequentially arranged from left to right, a cold fluid inlet of the first heat exchanger is connected with an air inlet, a cold fluid outlet of the sixth heat exchanger is connected with an air outlet, and a cold fluid outlet of the fourth heat exchanger is connected with an air outlet. The six heat exchangers are provided with hot fluid inlets and hot fluid outlets, the second heat exchanger is connected with a steam inlet pipe through a pipeline, the hot fluid outlets of the second heat exchanger are connected with a condensate pipe through a pipeline, and a drain valve is arranged in the middle of the condensate pipe. Hot fluid inlets of the first group of heat exchangers are respectively connected with the left part of a condensate pipe through pipelines, hot fluid outlets of the first group of heat exchangers are respectively connected with a condensate water outlet pipe throug