| 摘要 |
PURPOSE: To solve various problems possessed by a purifying tank using conventional FRP by forming specific ribs having a specific uneven shape by utilizing a crosslinked polymer obtained by polymerizing and crosslinking metathesis polymerizable cyclic olefin in a mold using a metathesis polymerization catalyst. CONSTITUTION: At least, upper and lower tank parts have a large number of square uneven ribs in a vertical direction. The respective uneven ribs satisfy 10<=H<=50, 30<=W<=200, 2<=R<=H, 2<=R'<=H and 3<=t excepting a contact aeration tank part. The uneven ribs in the contact aeration tank part satisfy 10<=H'<=80, 30<=W'<=300, 2<=Q<=H', 2<=Q'<=H' and 3<=t'. Further, in a large- scaled purifying tank, the height H' of the uneven ribs of the contact aeration tank of at least the upper or low tank part is higher than the height H of the uneven ribs of other tank. By this constitution, the large-scaled purifying tank capable of being reduced in wt, strong against an impact, having durability and pressure resistance and capable of being recycled is obtained. |
