Sewer sewage suction pipe fixing device and sewer desilting method

The invention belongs to the technical field of municipal sewage discharge, and discloses a sewer sewage suction pipe fixing device which comprises an annular mounting frame body, a plurality of well mouth supporting assemblies and a plurality of sewage suction pipe clamping assemblies, the well mouth supporting assemblies are evenly distributed around the axis of the mounting frame body, and the sewage suction pipe clamping assemblies are arranged on the well mouth supporting assemblies. The wellhead supporting assembly comprises a first adjusting part connected with the mounting frame body and a clamping block arranged on one side of the first adjusting part, and the first adjusting part is used for adjusting the clamping block to be close to or away from a sewer wellhead, so that the device can adapt to sewer wellheads with different calibers; the sewage suction pipe clamping assemblies and the wellhead supporting assembly are distributed at intervals around the axis of the mounting frame body, each sewage