METHOD OF TRANSPORTING ABSORBENT RESIN POWDER

• US 20110088806A1
• Filed: 03/26/2009
• Published: 04/21/2011
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: Nippon Shokubai Company Limited
• Original Assignee: Nippon Shokubai Company Limited
• Inventors: Matsumoto, Koji, Nakamura, Masatoshi, Nogi, Kozo, Awai, Kazuma
• Granted Patent: US 9,175,142 B2
• Time in Patent Office: Days
• US Class Current: 141/1
• CPC Class Codes: C08F 6/008 Treatment of solid polymer wetted by water or organic solvents, e.g. coagulum, filter cakes
• CPC Class Codes: C08J 2333/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C08J 3/075 Macromolecular gels
• CPC Class Codes: C08J 3/12 Powdering or granulating
• CPC Class Codes: C08J 3/245 Differential crosslinking of one polymer with one crosslinking type, e.g. surface crosslinking

Abstract

Provided is a method of transporting an absorbent resin powder, said method being suitable for long-distance transport, and being able to inhibit the deterioration of the properties of the absorbent resin powder while also inhibiting obstructions. During the manufacturing process, the absorbent resin powder is transported pneumatically via transport pipes. This transport method involves two or more air transport devices (A, B, C) within one transport section, and the air transport devices (A, B, C) are connected in series by transport pipes (P1, P2, P3).

Claims

1. A transportation method for a water-absorbing resin powder substance by pneumatic transportation of the water-absorbing resin powder substance during a production step via transportation pipelines, wherein two or more pneumatic transportation apparatuses are used in one transportation section, and the two or more pneumatic transportation apparatuses are connected by the transportation pipelines in series.

2. The transportation method according to claim 1, wherein total length Lt of the transportation pipelines included in the one transportation section is equal to or longer than 50 m.

3. The transportation method according to claim 1, wherein length Lp of each transportation pipeline included in the one transportation section is equal to or shorter than 40 m.

4. The transportation method according to claim 1, wherein linear velocity at a terminal of the transportation pipeline of the water-absorbing resin powder substance is equal to or lower than 15 m/s.

5. The transportation method according to claim 1, wherein the pneumatic transportation apparatus has a pressurized tank and a receiving hopper.

6. The transportation method according to claim 5, wherein a valve is provided between the pressurized tank and the receiving hopper, and open-close of the valve and start up of the pneumatic transportation apparatus are automatically controlled, based on detection result of a powder level of the receiving hopper.

7. The transportation method according to claim 5, wherein a valve is provided between the pressurized tank and the receiving hopper, and open-close of the valve and start up of the pneumatic transportation apparatus are automatically controlled, based on detection result of pressure in the pressurized tank.

8. The transportation method according to claim 1, wherein total length Lt of the transportation pipelines included in the one transportation section is equal to or longer than 100 m.

9. The transportation method according to claim 1, wherein the pneumatic transportation apparatus is a pneumatic transportation apparatus in high concentration.

10. The transportation method according to claim 1, comprising a step for storing the water-absorbing resin powder substance pneumatically transported.

11. The transportation method according to claim 1, wherein transportation amount of the water-absorbing resin powder substance is equal to or higher than 1000 kg/hr.

12. The transportation method according to claim 1, wherein the water-absorbing resin powder substance has been surface cross-linked with a polyhydric alcohol.

13. The transportation method according to claim 1, wherein the water-absorbing resin powder substance comprises a polyvalent metal salt.

14. The transportation method according to claim 1, wherein the water-absorbing resin powder substance comprises an inorganic particle.

15. The transportation method according to claim 1, wherein saline flow conductivity (SFC) for 0.69% by mass normal saline solution, of the water-absorbing resin powder substance before and after transportation is equal to or larger than 10 (×

10<sup>−

7</sup>·

cm³·

s·

g<sup>−

1</sup>).

16. The transportation method according to claim 1, wherein the water-absorbing resin powder substance is an irregular pulverized shaped polyacrylic acid (salt)-based water-absorbing resin obtained by continuous belt polymerization or continuous kneader polymerization.

17. The transportation method according to claim 1, wherein the water-absorbing resin powder substance is a polyacrylic acid (salt)-based water-absorbing resin obtained by a production step comprising a fine powder recycling step.

18. The transportation method according to claim 1, wherein the water-absorbing resin powder substance is a polyacrylic acid (salt)-based water-absorbing resin made by being surface cross-linked at 150 to 250°

C.

19. The transportation method according to claim 2, wherein length Lp of each transportation pipeline included in the one transportation section is equal to or shorter than 40 m.

20. The transportation method according to claim 2, wherein linear velocity at a terminal of the transportation pipeline of the water-absorbing resin powder substance is equal to or lower than 15 m/s.