Method for belching water from swollen superabsorbent polymers and method for recycling sanitary absorbent articles using the same
The present invention relates to a method for removing water from swollen superabsorbent polymers in a gel state, and a method for recycling sanitary absorbent articles using the same. According to the method of the present invention, water is removed from swollen superabsorbent polymers by immersing swollen superabsorbent polymers in a gel state into a composition wherein sea water that is readily available and calcium chloride that is readily available at low cost are mixed for a specified period of time. The method makes it possible to easily and economically remove water from swollen SAPs in a gel state. Thus, the method provides an economical and environmentally-friendly means for recycling sanitary absorbent articles comprising an absorbent that consists of SAP and cellulose pulp, after being used for absorbing human waste.
1. A method for belching water from superabsorbent polymers (SAPs) swollen with water from human waste, the method comprising:
immersing the water-swollen SAP in a gel state, taken from a sanitary absorbent article, into a composition for removing the human-waste-based water, wherein the composition includes sea water and 0.5 to 3% by weight of calcium chloride based on the weight of sea water.
2. The method according to claim 1 , wherein the swollen SAP in a gel state absorbs 40 to 1,000 g of moisture per 1 g of SAP.
3. The method according to claim 1 , wherein the sea water is natural sea water that does not undergo further processing or purification, or artificial sea water.
4. The method according to claim 1 , wherein the sea water comprises 2.0 to 4.0% by weight of salts based on the total weight of sea water.
5. The method according to claim 4 , wherein the sea water comprises 1.5 to 3.1% by weight of sodium chloride and 0.4 to 0.8% by weight of alkaline earth ion, based on the total weight of sea water.
6. The method according to claim 1 , wherein the composition for removing moisture has a pH ranging from 7.0 to 8.0.
7. A method for recycling sanitary absorbent articles wherein water from human waste is removed using the method according to claim 1 .
8. The method according to claim 7 , wherein the sanitary absorbent article comprises an absorbent consisting of superabsorbent polymer and cellulose pulp.
9. The method according to claim 8 , wherein the sanitary absorbent article is a diaper.