Method for producing water-absorbent resin powder, and drying device and drying method for particulate hydrous gel

A drying device for a particulate crosslinked hydrogel polymer obtained from a monomer that is a material of a water-absorbent resin, the drying device comprising:

• a rotary container that contains the particulate crosslinked hydrogel polymer therein and rotates;
• a plurality of heating tubes that are located within the rotary container, extend in an axial direction of the rotary container, and rotate together with the rotary container;
• and
• a means for introducing and discharging a gas into and from the rotary container, wherein
• a number of heating tubes is not less than five,
• the heating tubes are not in contact with an inner surface of the rotary container in the axial direction, and
• the drying device comprises a heating means or a thermal insulating means on an outer peripheral surface of the rotary container.

A production equipment for water-absorbent resin powder, the production equipment including a drying device, the production equipment comprising:

• a polymerization device for obtaining a crosslinked hydrogel polymer from a monomer that is a material of a water-absorbent resin;
• and
• a gel-crushing device for grinding the crosslinked hydrogel polymer to obtain a particulate crosslinked hydrogel polymer, wherein
• the drying device serves to dry the particulate crosslinked hydrogel polymer to obtain dried particles, and
• the drying device includes a rotary container that contains the particulate crosslinked hydrogel polymer therein and rotates, and a plurality of heating tubes that are located within the rotary container and extend in an axial direction of the rotary container.