Abstract: A production method for producing a particle mixture in which two or more types of particles are mixed, including a step of adding a first additive to first particles and mixing the first additive with the first particles using a first mixer and a step of introducing the two or more types of particles including the first particles mixed with the first additive and second particles into a blender container of a gravity blender, and mixing the two or more types of particles inside the blender container.

Abstract: An apparatus for producing water-absorbing resin particles for which surface cross-linking treatment is conducted, the surface cross-linking treatment being conducted by spraying a surface cross-linking agent to a water-absorbing resin particle precursor and heating the agent and the precursor, the apparatus includes a treatment container in which the surface cross-linking treatment is conducted, a stirring device including a stirring member disposed in the treatment container, a heating device that heats an inside of the treatment container; and a spray nozzle disposed in the treatment container, the spray nozzle spraying into the treatment container the surface cross-linking agent supplied from a surface cross-linking agent supply source in an exterior of the treatment container through a supply pipe. In a flow path in the spray nozzle spanning from an entrance of the spray nozzle to a spray exit, a point whose opening cross-section is smallest in a flow path through which a fluid passes is the spray exit.

Abstract: An apparatus for producing water-absorbing resin particles for which surface cross-linking treatment is conducted, the surface cross-linking treatment being conducted by spraying a surface cross-linking agent to a water-absorbing resin particle precursor and heating the agent and the precursor, the apparatus includes a treatment container in which the surface cross-linking treatment is conducted, a stirring device including a stirring member disposed in the treatment container, a heating device that heats an inside of the treatment container; and a spray nozzle disposed in the treatment container, the spray nozzle spraying into the treatment container the surface cross-linking agent supplied from a surface cross-linking agent supply source in an exterior of the treatment container through a supply pipe. In a flow path in the spray nozzle spanning from an entrance of the spray nozzle to a spray exit, a point whose opening cross-section is smallest in a flow path through which a fluid passes is the spray exit.

Abstract: Filling of a powder particle material is executed for a flexible container bag (hereinafter, referred to as “flex container bag”) by executing a powder particle material filling step of filling the flex container bag with the powder particle material by supplying the powder particle material to the flex container bag, and a tapping step of executing a lifting operation of lifting up the flex container bag filled with the powder particle material to cause the flex container bag to be distant from a floor surface or a base bed thereabove and a dropping operation of dropping the flex container bag by releasing the lifting by the lifting operation to cause the flex container bag to collide with the floor surface or the base bed. The handling property of the flex container bag filled with the powder particle material can further be improved.

Abstract: An apparatus for producing water-absorbing resin particles for which surface cross-linking treatment is conducted by spraying a surface cross-linking agent to a water-absorbing resin particle precursor and heating the agent and the precursor, the apparatus includes a treatment container in which the surface cross-linking treatment is conducted, a stirring device including a stirring member disposed in the treatment container, a heating device that heats an inside of the treatment container; and a spray nozzle disposed in the treatment container, the spray nozzle spraying into the treatment container the surface cross-linking agent supplied from a surface cross-linking agent supply source in an exterior of the treatment container through a supply pipe. In a flow path in the spray nozzle spanning from an entrance of the spray nozzle to a spray exit, a point whose opening cross-section is smallest in a flow path through which a fluid passes is the spray exit.

Abstract: Provided is a production method with which a large amount of particle mixture in which two or more types of particles are mixed can be easily produced. The production method is for producing a particle mixture in which two or more types of particles are mixed, and includes the following steps (1) and (2): (1) a step of adding a first additive to first particles and mixing the first additive with the first particles using a first mixer; and (2) a step of introducing the two or more types of particles including the first particles mixed with the first additive and second particles into a blender container of a gravity blender, and mixing the two or more types of particles inside the blender container.

Abstract: An apparatus for producing water-absorbing resin particles for which surface cross-linking treatment is conducted by spraying a surface cross-linking agent to a water-absorbing resin particle precursor and heating the agent and the precursor, the apparatus includes a treatment container in which the surface cross-linking treatment is conducted, a stirring device including a stirring member disposed in the treatment container, a heating device that heats an inside of the treatment container; and a spray nozzle disposed in the treatment container, the spray nozzle spraying into the treatment container the surface cross-linking agent supplied from a surface cross-linking agent supply source in an exterior of the treatment container through a supply pipe. In a flow path in the spray nozzle spanning from an entrance of the spray nozzle to a spray exit, a point whose opening cross-section is smallest in a flow path through which a fluid passes is the spray exit.