The invention concerns a gelling material (10) for gelling aqueous fluids, medical wastes containing aqueous fluids, body fluids collected by suction in body fluid suction equipment. The gelling material (10) comprises a water-absorbent composed of a water-absorbing resin (3) in the form of powders or granules, the water-absorbent being wrapped in water-disintegrating paper (1) or a water-soluble film (2) or a laminate sheet obtained by laminating water-disintegrating paper (1) and a water-soluble film (2). The invention also concerns a method of gelling aqueous fluid and medical waste by adding the gelling material (10) to the aqueous fluid or medical waste. The aqueous fluid or medical waste can be gelled conveniently and in a short period of time. The gel (10) thus produced never releases absorbed fluid even when an external pressure is applied to it.
Thus, the invention is useful for the treatment of aqueous fluids such as sludge-like wastes produced in plants and also of medical wastes and body fluids.