| 摘要 |
The invention relates to a production method for producing water-absorbing polymer particles, wherein the production method comprises the following steps: polymerizing an aqueous monomer solution or suspension in order to produce an aqueous polymer gel, drying the aqueous polymer gel in a belt dryer having a conveyor belt, the aqueous polymer gel being accommodated on the conveyor belt and the polymer gel being conveyed on the conveyor belt in a conveying direction (C), fracturing and/or grinding the dried polymer gel in order to form water-absorbing polymer particles. According to the invention, in order to perform drying: the belt dryer is formed having a dryer structure (101) largely encompassing the conveyor belt and having an air return guide (350) that connects to the dryer structure (101) in such a way that air is returned, wherein return air (RL) is drawn from the dryer structure (101) and is fed back to the dryer structure (101) via the air return guide (350), and the air return guide (350) has an air-drawing guide (340), which is formed between an input segment (EA) at the dryer structure (101) arranged upstream in the direction of air flow and an output segment (AA) in the air return guide (350) arranged downstream in the direction of air flow, <b>characterized in that</b> a flow cross-section in at least one air-removing segment (A, A1, A2, A3, A4) of the air-drawing guide (340) has a cross-section enlargement (Q, Q1, Q2, Q3, Q4), wherein the cross-section enlargement enlarges a cross-section of the air-removing segment (A, A1, A2, A3, A4) of the air-drawing guide in such a way that at least in the air-removing segment (A, A1, A2, A3, A4) of the air-drawing guide (340), the return air (RL) is led away at a reduced flow velocity, in particular at a reduced flow velocity that is lower than at a cross-section of the air-drawing line arranged upstream in the direction of air flow and/or than an input velocity at the input segment (EA), and/or at least in an input segment (EA) of the air-drawing guide (340) having an enlarged cross-section, the return air (RL) is led away at a reduced input velocity, in particular at a reduced flow velocity that is lower than at a cross-section of the air-drawing line arranged downstream in the direction of air flow. |
