Water amount controlling method and desalination system

Patent metadata

Field	Value
Publication number	US-9822018-B2
Application number	US-201414554380-A
Country	US
Kind code	B2
Filing date	Nov 26, 2014
Priority date	Mar 28, 2013
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A water amount controlling method according to the present disclosure includes: opening a discharge valve that discharges a liquid from a water tank if an impurity concentration is higher than or equal to a first reference value, and opening a sluice gate that introduces the liquid to the water tank a predetermined period after opening the discharge valve, the first reference value being lower than a saturation concentration; throttling the discharge valve and the sluice gate if the impurity concentration is higher than or equal to a second reference value and the temperature is lower than or equal to a third reference value, the second reference value being lower than the first reference value; and closing the discharge valve if the impurity concentration is lower than the second reference value, and closing the sluice gate a predetermined period after closing the discharge valve.

First claim

The invention claimed is:

1. A water amount controlling method for a desalination system including:
a water tank having a space for storing a liquid;
a lid covering an opening of the water tank;
a water-repellent particle layer that is located below the water tank and contains a plurality of water-repellent particles;
a liquefying layer that is located below the water-repellent particle layer and liquefies water vapor that has passed through the water-repellent particle layer to obtain fresh water, the liquefying layer containing a plurality of particles that have not been treated to be water-repellant;
a temperature sensor that measures a temperature of the liquid stored in the water tank;
a concentration sensor that measures an impurity concentration of the liquid stored in the water tank; and
a water amount controlling device having a processor, the water amount controlling device controlling an amount of the liquid to be introduced to or discharged from the water tank based on the temperature measured by the temperature sensor and the impurity concentration measured by the concentration sensor, the water amount controlling method comprising:
opening a discharge valve that discharges the liquid from the water tank if the impurity concentration measured by the concentration sensor is higher than or equal to a first reference value, and opening a sluice gate that introduces the liquid to the water tank a predetermined period after opening the discharge valve, the first reference value being lower than a saturation concentration;
after the water amount controlling device opens the discharge valve and the sluice gate, throttling the discharge valve to reduce a flow of the discharge of the liquid from the water tank and throttling the sluice gate to reduce a flow of introducing the liquid to the water tank, if the impurity concentration measured by the concentration sensor is higher than or equal to a second reference value and the temperature measured by the temperature sensor is lower than or equal to a third reference value, the second reference value being lower than the first reference value; and
after the water amount controlling device throttles the discharge valve and the sluice gate, closing the discharge valve if the impurity concentration measured by the concentration sensor is lower than the second reference value, and closing the sluice gate a predetermined period after closing the discharge valve; the opening, the throttling and the closing being performed by the water amount controlling device.

2. The water amount controlling method according to claim 1 ,
wherein the temperature sensor and the concentration sensor are located at a position above the water-repellent particle layer and at a bottom of the water tank.

3. The water amount controlling method according to claim 1 ,
the concentration sensor is located in the water tank at a position closer to a position of the discharge valve than to where the liquid is introduced from the sluice gate to the water tank.

4. The water amount controlling method according to claim 3 ,
wherein the temperature sensor is located in the water tank at a position closer to where the liquid is introduced from the sluice gate than to the position of the discharge valve.

5. The water amount controlling method according to claim 1 , further comprising:
heating and evaporating the liquid above the water-repellent particle layer to generate water vapor; and
liquefying the water vapor in the liquefying layer to obtain the fresh water.

6. A desalination system comprising:
a desalination apparatus including (i) a water tank having a space for storing a liquid, (ii) a lid covering an opening of the water tank, (iii) a water-repellent particle layer that is located below the water tank and contains a plurality of water-repellent particles, and (iv) a liquefying layer that is located below the water-repellent particle layer to obtain fresh water, the liquefying layer containing a plurality of particles that have not been treated to be water-repellant;
a temperature sensor that measures a temperature of the liquid stored in the water tank;
a concentration sensor that measures an impurity concentration of the liquid stored in the water tank
a discharge valve that discharges the liquid stored in the water tank; and
a water amount controlling device having a processor, the water amount controlling device being configured to control an amount of the liquid to be introduced to or discharged from the water tank based on the temperature measured by the temperature sensor and the impurity concentration measured by the concentration sensor,
wherein the water amount controlling device is configured to:
open the discharge valve if the impurity concentration measured by the concentration sensor is higher than or equal to a first reference value, and open a sluice gate that introduces the liquid to the water tank a predetermined period after opening the discharge valve, the first reference value being lower than a saturation concentration;
after the water amount controlling device opens the discharge valve and the sluice gate, throttle the discharge valve to reduce a flow of the discharge of the liquid from the water tank and the sluice gate to reduce a flow of introducing the liquid to the water tank, if the impurity concentration measured by the concentration sensor is higher than or equal to a second reference value and the temperature measured by the temperature sensor is lower than or equal to a third reference value, the second reference value being lower than the first reference value; and
after the water amount controlling device throttles the discharge valve and the sluice gate, close the discharge valve if the impurity concentration measured by the concentration sensor is lower than the second reference value, and close the sluice gate a predetermined period after closing the discharge valve.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Tomiyama Morio
• Gyoten Hisaaki
• Mino Norihisa
• Taomoto Akira
• Ono Atsushi
• John Stephen William

Classifications

• Y02W10/37

  using solar energy · CPC title

• C02F1/043 Primary

  Details · CPC title

• C02F2103/08

  Seawater, e.g. for desalination · CPC title

• B01D3/42

  Regulation; Control · CPC title

• B01D1/22

  by bringing a thin layer of the liquid into contact with a heated surface {(B01D1/065 takes precedence)} · CPC title