If the inner tank leaks, the gas or detection liquid with certain pressure inside the double gap will enter the normal pressure inner tank; the pressure or liquid level inside the double gap will change and trigger the sound and light alarm. After the storage liquid leaks into the double-layer gap, the storage liquid will not leak out because the outer tank is intact. Therefore, the stored liquid, soil and groundwater are safe. If the outer tank leaks, gas or detection fluid with a certain pressure inside the double-layer gap will enter the soil. Likewise, the pressure or liquid level inside the double-layer gap will change and trigger an audible and visual warning. At this time, the stored liquid is safe because the inner tank is intact; only the gas or detection liquid enters the soil, therefore, the soil and groundwater are also safe. Since the storage liquid contacted by the inner tank and the soil and groundwater contacted by the outer tank belong to different media and have different corrosion rates on the tank material, the probability of leakage at the same time is almost zero. Therefore, the phenomenon of storage liquid leaking out of the tank can be eliminated, which realizes safe production and protects the environment.
