17.
    发明专利
    未知

    公开(公告)号:AT496945T

    公开(公告)日:2011-02-15

    申请号:AT06725287

    申请日:2006-03-23

    Applicant: BASF SE

    Abstract: Preparation of water-absorbing polymers (A) with drying quality index comprises polymerizing a monomer solution and drying the obtained hydrogel agent in hot-gas flow, where the drying process takes place in at least two temperature zones, when the flow of the hydrogel in the gas flow is: downwards in the front side of the volume drier, and upwards against the rear side of the drier; where the amount of water in the hydrogel is 15-45 wt.%, the hydrogel layer in the volume drier flows at least partially against down wards, and the speed of the gas is 5-30%. Preparation of water-absorbing polymers (A) with drying quality index comprises polymerizing a monomer solution and drying the obtained hydrogel agent in hot-gas flow, where the drying process takes place in at least two temperature zones, when the gas inlet temperature (T n) is not equal to T n + a; and flow of the hydrogel in the gas flow is: downwards in the front side of the volume drier, and upwards against the rear side of the drier; where the amount of water in the hydrogel is 15-45 wt.%, the hydrogel layer in the volume drier flows at least partially against down wards, and the speed of the gas is 5-30%. n : index; and a : greater than 0. An independent claim is included for a device for drying (A) comprising a gas permeable conveyer belt (which is streamed by a preheated gas), where the gas inlet temperature is adjusted such that it can come form at least two temperature zones.

Patent Agency Ranking