Abstract: In the light of higher consumption of raw material and serious environment pollution during site derusting of large-scale tanks, development of environment-friendly deruster for large-scale tanks is carried out.Structure and design characteristics of the deruster are introduced and primary constitution of the deruster such as magnetic crawling mechanism and adsorbing system, obturator, electrical controlling system, safety/protection device, blast cleaning device and recycling/purlfying system are described in emphasis.Design and calculation on weight-bearing, sand pot, internal pressure cylinder, inner/outer pressure conical shell of magnetic crawling mechanism are provided.Pilot scale test shows that this deruster has considerable advantages in improving blasting operation environment, reducing labor intensity and/or operation cost.