Piping system

A piping system, comprising:

• a supporting structure;
• a plurality of scrubbers, disposed on the supporting structure;
• a collecting pipe, having a main body and a plurality of protrusions, wherein the main body has an outer surface and a first central axis, and the protrusions are disposed on the main body and protrude from the outer surface, wherein the protrusions are arranged to surround the outer surface;
• a plurality of connecting pipes, connecting the scrubbers to the collecting pipe, wherein the main body communicates with the scrubbers via the protrusions and the connecting pipes;
• and
• a drain pipe, disposed under the supporting structure and having a second central axis, and the supporting structure is between the scrubbers and the drain pipe in a direction of the first central axis, wherein the collecting pipe is perpendicular to and passes through the supporting structure and the bottom of the collecting pipe in the direction of the first central axis directly connects the drain pipe, and the first central axis is perpendicular to the second central axis.