Apparatus and methods for treating ballast water by using electrolysis of natural seawater

• US 20070158208A1
• Filed: 12/21/2004
• Published: 07/12/2007
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: Research Institute of Industrial Science and Technology
• Original Assignee: Research Institute of Industrial Science and Technology
• Inventors: Kim, Kwang-Il, Kim, Young-Deog, Kim, Heung-Rak, Jung, Woo-Chul
• Granted Patent: US 7,540,251 B2
• Time in Patent Office: Days
• US Class Current: 205/742
• CPC Class Codes: B63B 17/00 Vessels parts, details, or accessories, not otherwise provided for vehicle fittings for preventing or indicating unauthorised use or theft of vehicles in general B60R25/00; propeller guards, line cutters or other means for protecting propellers or rudders B63H5/165; protection of power legs of outboard propulsion units B63H20/36; locking devices for boats, surfboards or parts or accessories thereof E05B73/007
• CPC Class Codes: B63J 4/00 Arrangements of installations for treating ballast water, waste water, sewage, sludge, or refuse, or for preventing environmental pollution not otherwise provided for; centrifugal bilge-water separators B04; discharge of refuse, e.g. for ash B63B17/06; arrangements on tanks for fuel or the like for minimizing pollution by accidents B63B17/0036, associated with cargo tanks B63B25/082; vessels for collecting pollution from open water B63B35/30; soil-water discharges B63B29/16; treating waste water, sewage, or sludge, in general, C02F; cleaning or keeping clear the surface of open water, in general E02B15/00
• CPC Class Codes: C02F 1/4674 with halogen or compound of halogens, e.g. chlorine, bromine
• CPC Class Codes: C02F 2103/008 Originating from marine vessels, ships and boats, e.g. bilge water or ballast water
• CPC Class Codes: C02F 2201/4612 Controlling or monitoring
• CPC Class Codes: C02F 2201/46125 Electrical variables
• CPC Class Codes: C02F 2209/006 comprising a software program or a logic diagram
• CPC Class Codes: C02F 2209/29 Chlorine compounds
• CPC Class Codes: C02F 2209/42 Liquid level
• CPC Class Codes: Y02W 10/37 using solar energy

Abstract

An electrolysis-type apparatus for treating ballast water using NaOCl and a method thereof is provided. The apparatus includes: a ballast tank; an electrolyzer; a first circulation pump; a second circulation pump; and a controller. The ballast tank is installed in a ship to store seawater. The electrolyzer is connected with the ballast tank and electrolyzes the seawater. The circulation pumps are installed to allow the ballast water to flow into the electrolyzer and to discharge the electrolyzed water containing NaOCl to the ballast tank. The controller supplies power to the electrolyzer so as to control an NaOCl density and controls the circulation pumps. The apparatus and the method safely treat the seawater. Thus, environment pollution and ecosystem destruction can be minimized.

Claims

1. An apparatus for treating ballast water in a ship, the apparatus comprising:

a ballast tank installed in a lower portion of the ship, for storing seawater;

an electrolyzer connected with the ballast tank, for electrolyzing the seawater;

a first circulation pump installed between the ballast tank and the electrolyzer, for allowing the ballast water to flow into the electrolyzer;

a second circulation pump for discharging the electrolyzed seawater containing NaOCl from the electrolyzer to the ballast tank; and

a controller for supplying power to the electrolyzer so as to control an NaOCl density of the ballast water and controlling the circulation pumps.

2. The apparatus of claim 1, wherein an NaOCl density detection sensor is installed in at least one position selected among an inside of the electrolyzer, an inlet of the ballast tank and a bottom of the ballast tank.

3. The apparatus of claim 1, further comprising valves for controlling inflow and outflow amounts of the seawater installed between the ballast tank and the respective circulation pumps.

4. The apparatus of claim 3, wherein each of the valves is a solenoid valve.

5. The apparatus of claim 1, wherein the controller comprises a direct-current voltage supply unit for converting an alternating-current voltage into a direct-current voltage and supplying the direct-current voltage to electrodes of the electrolyzer.

21. The apparatus of claim 2, further comprising valves for controlling inflow and outflow amounts of the seawater installed between the ballast tank and the respective circulation pumps.

6. A method for treating ballast water in a ship using electrolysis, the method comprising steps of:

taking in seawater into a ballast tank;

operating a circulation pump to allow the seawater of the ballast tank to flow into an electrolyzer where electrodes for electrolysis are installed;

converting, at the electrolyzer, NaCl contained in the seawater into NaOCl through electrolysis; and

discharging the seawater containing NaOCl to the ballast tank through a circulation pump.

7. The method of claim 6, wherein an NaOCl density detection sensor is installed in order to maintain an NaOCl density constant to control a seawater circulation amount of the electrolyzer or a direct-current voltage supply depending on the detection results.

8. The method of claim 6, further comprising steps of, after the step of discharging:

measuring an NaOCl density to judge whether the NaOCl density reaches a required density;

if the density reaches the required density, stopping the circulation pump; and

if the density does not reach the required density, circulating the ballast water until the density reaches the required density.

9. The method of claim 8, wherein the step of measuring the NaOCl density is performed on at least one point among an inside of the electrolyzer, and inlet of the ballast tank and a bottom of the ballast tank.

10. The method of claim 6, further comprising the step of, after the step of taking in:

judging whether the intake of the seawater is completed using a water-level detection device provided to an inside of the ballast tank.

11. An apparatus for treating ballast water in a ship, the apparatus comprising:

a ballast tank installed in a lower portion of the ship, for storing seawater;

an intake pump for taking in seawater and supplying the seawater to the ballast tank;

an electrolyzer position between the ballast tank and the intake pump, for electrolyzing the seawater supplied to the ballast tank from the intake pump; and

a controller for controlling power supplied to the electrolyzer and controlling the intake pump to adjust an NaOCl density of the seawater contained in the ballast tank.

12. The apparatus of claim 11, wherein the electrolyzer has a body of a cavity shape and both side ends of the body are respectively connected with a pipe extended from the intake pump to the ballast tank in a manner of flange-joining.

13. The apparatus of claim 12, wherein the body is of a cylindrical shape.

14. The apparatus of claim 12, wherein the body of the electrolyzer has a plurality of electrodes consisting of anodes and cathodes arranged in its inside and the electrodes are electrically connected with a direct-current-voltage supply unit so that a direct-current power converted from an alternating current is supplied and electrolysis of the seawater is performed.

15. The apparatus of claim 12, wherein the pipe uniformly discharges the ballast water through a discharge line and a discharge nozzle arranged along a top side of the ballast tank so that the generated NaOCl component is easily diffused inside the ballast tank.

16. The apparatus of claim 11, wherein at least one of the ballast tank and the electrolyzer has an NaOCl density detection sensor for detecting an NaOCl density installed.

17. A method for treating ballast water in a ship using electrolysis, the method comprising steps of:

taking in seawater into a ballast tank;

passing the taken-in seawater through an electrolyzer where electrodes for electrolysis are installed to generate electrolyzed water containing NaOCl; and

allowing the electrolyzed water containing NaOCl to flow into the ballast tank.

18. The method of claim 17, further comprising steps of, after the step of allowing the electrolyzed water to flow into the ballast tank:

measuring an NaOCl density;

adjusting, at the electrolyzer, a direct-current voltage and current; and

controlling a ballast water density until the density reaches a required density by adjusting an intake amount of the seawater using an intake pump.

19. The method of claim 18, further comprising steps of, after the step of controlling the ballast water density:

judging whether the intake of the seawater is completed using a water-level detection device provided to an inside of the ballast tank; and

operating the intake pump until the seawater reaches a desired intake amount.

20. The method of claim 18, wherein the step of measuring the NaOCl density is performed using an NaOCl density detection sensor positioned in the ballast tank.