JPH03106462A - Method for desalting sand by utilizing regenerated water - Google Patents

Abstract

PURPOSE:To effectively desalt sand containing salt by combining a process storing salt water on a metal plate and evaporating the same by solar heat to recover moisture and a process for sprinkling the fresh water regenerated in said process over sand containing salt to obtain desalted sand and salt water. CONSTITUTION:In a fresh water making process, salt water obtained by sprinkling water on salt-containing sand S is stored on a metal plate 3 and evaporated by solar heat to recover moisture in a regenerated water tank T2. Further, in a desalting process, the fresh water recovered by the fresh water making process is sprinkled over salt-containing sand S by a water sprinkling apparatus 2 to obtain desalted sand and salt water. As a result, the salt contained in sea sand or desert sand can be efficiently and economically reduced and used water can be reutilized.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a method for removing salt from sand, which is applied to desert greening, sea sand cleaning, etc. (Prior art) Conventionally, methods for removing salt from salt-containing sand include depositing lit-salt-containing sand in a yard, showering it with water, and then draining it. , a method was used to wash sand and remove salt by rotating the same trommel while sprinkling water. (This is a problem that the invention aims to solve!) However, the former method requires 0 fresh water per 1 nf of salt-containing sand. .25nf is required, and the used water is discharged as is, which is uneconomical as it uses a large amount of water, and discharging water into rivers causes pollution.The latter method also requires a large amount of fresh water. The present invention was proposed in view of the problems of the prior art described above, and its purpose is to remove sea sand. The purpose of this invention is to provide a method for removing salt from sand that efficiently and economically reduces the salt content in sand such as sand and desert sand, and also enables the reuse of water used. In order to achieve the above object, the method for removing salt from sand according to the present invention stores salt water obtained by sprinkling water on salt-containing sand on a metal plate, and evaporates it by solar heat. The process consists of a fresh water conversion process that recovers the water that has been removed, and a desalination process that produces salt-free sand and salt water by sprinkling the fresh water recovered in the same process onto salt-containing sand. (Function) According to the invention, as described above, the salt water obtained in the process of removing salt from salt-containing sand is stored on a metal plate, the water evaporated by solar heat is recovered, and the thus obtained recycled water is used to remove salt from salt-containing sand. By sprinkling water on the sand, the sand is desalinated, and the salt water separated from the sand is again supplied onto the metal plate, and the above steps are repeated to remove salt from the sand containing salt water. (Embodiment) The present invention will be described below with reference to the illustrated embodiment.The figure shows a desalting device, and a salt water tank (T1) is disposed at the bottom of the abutment (1) on which salt-containing sand (S) is deposited. , a water sprinkling device (2) is installed at the top. (8 is a water purification device, in which the top of a metal plate, such as an iron plate (3), which becomes hot due to solar heat, is covered with a conical, impermeable or transparent Cover the sheet (4) and place a funnel-shaped water collection sheet (5) along the inner circumference of the lower part of the sheet (4).
), and a salt water supply pipe (6) connected to the salt water tank (11) in the salt removal device and equipped with a pump (2) is vertically installed from the top of the sheet (3). ing. A reclaimed water supply pipe (7) is connected to the water collection sheet (5), and the pipe (7) is sequentially connected to a fresh water tank (T■) and a water sprinkling device (2) in the salt removal device, A pump (PI) is interposed between the water sprinkler i (2) and the fresh water tank (T). Then, at night, the salt-containing sand {3 in the desalting device holder is sprinkled with fresh water recycled in the freshwater treatment device iii (B) via the water sprinkling device (2) to remove salt. The salt water used to remove salt from the sand S is stored in a salt water tank (↑1>), and during the day it is pumped (P8) to the iron plate (3 ), and only the moisture is evaporated by the iron plate (3) heated by solar heat. The evaporated moisture condenses on the surface of the sheet (4) and becomes fresh water, which flows down the inside of the sheet (4) and collects. Water sheet (
5), is led to the reclaimed water tank (T.), is led to the pump (P,), and is supplied to the water sprinkling device (2) via the reclaimed water supply pipe (7) by the pump (P8>), and is then supplied to the water spraying device (2), and is then fed to the water spraying device (2) via the reclaimed water supply pipe (7). Salt-containing sand (S) deposited on the abutment (1) in
Water is sprinkled on. In addition, there are multiple freshwater purification devices +81 around the desalination device.
By installing a deionizer and balancing the capacities of the demineralizer and demineralizer, it is possible to demineralize sand in an almost closed system with a small amount of make-up water. Furthermore, since the iron plate (3) is in a high temperature state due to solar heat and there is a possibility of rusting due to salt water, a sheet with good thermal conductivity that does not cause rusting may be placed on the iron plate (3). In addition, the pump (P
t) Solar energy or storage batteries may be used to power (h). Figures 2 to 4 show other embodiments of the present invention, in which small hemispherical convex portions (2a) are arranged in rows over the entire surface of the iron plate (2) in the water purification device (Bl), and A rising part (2b) is provided on the periphery, and the iron plate (2b) is lower than the surface of the salt water (Q).
) in the convex portion (2a). The structure is designed to protrude upward to easily receive solar heat and effectively evaporate salt water. By combining each of the above devices with a mobile device, it can be used for wide-ranging soil improvement. (Effects of the Invention) As described above, the present invention includes a freshening process in which salt water is stored on a metal plate and water is recovered by evaporation by solar heat;
Salt-containing sand can be effectively desalinated by combining the desalination step of sprinkling fresh water recycled from the salt water through the same process to obtain desalted sand and brine. According to the present invention, by using reclaimed water to remove salt from salt-containing sand, there is no pollution caused by wastewater, and only a small amount of make-up water is required, and the sand can be removed using an almost closed system. It is done. In addition, only the amount of power needed to pump up desalinated water or reclaimed water is required, and in combination with the fact that only a small amount of make-up water is required as mentioned above, sand desalination can be carried out economically. Furthermore, according to the present invention, salt is produced as a by-product on the gold rjAFi. According to a second aspect of the invention, hemispherical convex portions are arranged in rows on the metal plate surface to improve the evaporation effect of salt water on the metal plate surface due to solar heat.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of a sand desalination device using reclaimed water that implements the method of the present invention, Fig. 2 is a plan view of the iron plate part of the water purification device, Fig. 3 is a slight vertical cross-sectional view, and Fig. 4 is a partially enlarged view of Figure 3. Prisoner... desalination equipment, (BL
... Freshwater equipment, (1) ... Abutment, (
2) ...Water spray device, (3) ...Iron plate,
(4)... Transparent sheet, (5)... Water collection sheet, (6)... Salt water supply pipe, (7)... Reclaimed water supply pipe, (Tl)... Salt water tank, (ti )・
...Reclaimed water tank, (P,)...Pump, (P2)
···pump.

Claims (1)

[Scope of Claims] 1. A freshening process in which salt water obtained by sprinkling water on salt-containing sand is stored on a metal plate and water evaporated by solar heat is collected, and fresh water collected in the same process. A method for removing salt from sand by using reclaimed water, comprising: sprinkling water on salt-containing sand to obtain salt-removed sand and salt water. 2. The method for removing salt from sand by using reclaimed water according to claim 1, wherein hemispherical convex portions are arranged in rows on the surface of the metal plate.