KR101836819B1 - A heavy metal wastewater treatment facility and a method using ions which get through the pores of membrane - Google Patents

Abstract

The present invention relates to a treatment apparatus and a treatment method for removing heavy metals contained in wastewater, comprising a reaction tank into which wastewater flows; A hollow drum-shaped second membrane disposed inside the reaction vessel; And a compound filled in the inside of the second membrane, wherein the compound is an alkali metal compound or an alkaline earth metal compound.

Description

TECHNICAL FIELD [0001] The present invention relates to a heavy metal wastewater treatment facility and a method for treating heavy metal wastewater using ions passing through pores of a membrane,

The present invention relates to an apparatus and a method for treating heavy metals contained in wastewater using ions passing through pores of a membrane. Specifically, heavy metal ions contained in wastewater are ion-bonded to ions passing through membrane pores, And at the same time, the water introduced into the inside of another membrane is allowed to flow out of the reactor through a connection pipe connected to the inside of the membrane, and to a method and apparatus for treating heavy metal wastewater.

Due to rapid economic growth and rapid industrialization, the demand for heavy metals is increasing day by day. Most of them are toxic, which not only affects the human body and ecosystem but also acts as a serious pollutant to environment such as river and soil.

In particular, Korea has developed industrial development over a short period of time, and various pollutants have been discharged into rivers and rivers through general sewage, industrial wastewater, landfill of various wastes, and pesticide application, resulting in threats to human health as well as water environment .

The major sources of heavy metals are industrial wastewater, city sewage and pesticide spraying. In the plating industry, smelting, leather, pigment and pharmaceutical companies in industry are harmful to organisms such as cadmium, zinc, copper, nickel, lead, mercury and chromium. It is known to over-discharge heavy metals.

Water pollution by indiscriminate heavy metal emissions has been causing global problems for decades. Toxic metal elements that adversely affect humans and ecosystems in particular are As, Cr, Cu, Pb, Hg, Mn, Cd, Ni, Ni).

Heavy metals, unlike toxic organic compounds, are not biodegradable and are known to accumulate in organisms and cause a variety of diseases and disorders. Conventionally, a chemical precipitation method, an ion exchange resin and a removal method using a separation membrane have been proposed for the removal of heavy metals present in river water, ground water and wastewater.

However, the removal method using an ion exchange resin or a separation membrane has a problem in that it is difficult to treat contaminated water containing a large amount of solid pollutants, which is costly. Further, when the chemical precipitation method is used, there is a problem that the heavy metal at a low concentration can not be completely removed even after the heavy metal removal treatment.

Korean Patent Registration No. 10-1516827, which is a conventional technique for removing heavy metals in wastewater by using a membrane, will be described.

The conventional technique is a kind of chemical precipitation method in which the pH is controlled first and then the ammonia polymer is reacted to precipitate the heavy metal contained in the wastewater. Thereafter, the waste water is passed through the membrane to remove the solid matter remaining in the wastewater.

However, in the conventional technique, the low concentration heavy metals in the wastewater still can not be completely removed, and the operation of the device, which requires the addition and stirring of a separate polymer into the reaction tank, is troublesome.

In addition, when the polymer is not stirred uniformly in the wastewater, the efficiency of precipitation of heavy metal is low. Further, there is a fear that heavy metal is contained in the water flowing into the membrane while the pore size of the membrane is not limited .

In addition, since a process of adjusting the pH, a process of precipitating a heavy metal by injecting a polymer, and a process of passing the precipitated wastewater through a membrane are separately performed, a lot of processing space is required, and an additional facility The efficiency of treatment of heavy metals compared to facility investment is significantly lowered.

It is an object of the present invention to provide an apparatus and method for removing suspended solids in influent water in a single process, precipitating heavy metals in wastewater, and discharging the precipitate of water treated in the extruded state .

It is also intended to provide an apparatus and method for increasing the efficiency of heavy metal precipitation.

The present invention also provides an apparatus and method for increasing the efficiency and simplifying the facility in treating heavy metals in wastewater.

In order to solve the above-mentioned problems, the heavy metal wastewater treatment apparatus according to the present invention includes a reaction tank 100 into which wastewater flows; A second membrane 202 in the shape of a hollow drum positioned inside the reaction tank 100; And a compound positioned inside the second membrane (202), wherein the compound is any one of an alkali metal compound and an alkaline earth metal compound.

The waste water may be introduced into the reaction tank 100 through the first membrane 201. The first membrane 201 may be disposed in the reaction tank 100,

The third membrane 203 may further include a third membrane 203 in the form of a hollow drum disposed inside the reaction tank 100. Water flowing into the third membrane 203 may be introduced into the third membrane 203, And then flows out of the reaction tank 100 through a connection pipe connected to the inside.

Preferably, the alkali metal compound is sodium carbonate (Na ₂ CO ₃₎ or a bicarbonate (NaHCO ₃₎ carbonate, the alkaline earth metal compound is magnesium (MgO), calcium oxide (CaO) or calcium carbonate (CaCO ₃₎ oxide .

Preferably, the diameter of the pores of the second membrane 202 is 0.1 to 5 占 퐉.

Preferably, the time for which the wastewater stays in the reaction tank 100 is 1 to 24 hours.

In order to solve the above-described problems, the method of treating heavy metal wastewater according to the present invention is characterized in that (a) wastewater flows into a reaction tank 100 in which a second membrane 202 and a third membrane 203, ; (b) filling the inside of the second membrane 202 with an alkali metal compound or an alkaline earth metal compound; And (c) water introduced into the third membrane 203 flows out of the reaction tank 100 through a connection pipe connected to the inside of the third membrane 203.

Preferably, a hollow drum-shaped first membrane 201 is located inside the reaction vessel 100, and in step (a), wastewater is introduced into the reaction vessel 100 through the first membrane 201, Respectively.

Preferably, the alkali metal compound is sodium carbonate (Na ₂ CO ₃₎ or a bicarbonate (NaHCO ₃₎ carbonate, the alkaline earth metal compound is magnesium (MgO), calcium oxide (CaO) or calcium carbonate (CaCO ₃₎ oxide .

Preferably, the diameter of the pores of the second membrane 202 is 0.1 to 5 占 퐉.

In order to solve the above-mentioned problems, the heavy metal wastewater treatment method according to the present invention is a method of treating heavy metal wastewater containing heavy metals contained in wastewater by ionic bonding by carbonic acid ions or bicarbonate ions flowing in pores of a second membrane 202 having a diameter of 0.1 to 5 μm Precipitate.

As a means for solving the above-mentioned problems, the heavy metal in the wastewater can be precipitated in one process and the purified water introduced into the membrane can be discharged to the outside, which greatly simplifies the operation of the heavy metal processing apparatus. This increases cost efficiency.

In addition, a plurality of membranes can be positioned according to the size of the reaction vessel, and the distribution of the ions passing through the membrane pores is uniform, so that there is no need for any additional facilities necessary for stirring.

In addition, the heavy metal removal treatment can be continuously performed while the compound is continuously filled, and at the same time, the water that has been subjected to heavy metal removal can be discharged to the outside through the membrane, so that a large amount of wastewater can be continuously treated, .

1 is a view for conceptually explaining technical characteristics of a second membrane in a heavy metal wastewater treatment apparatus according to the present invention.
FIG. 2 is a diagram for explaining the overall technical characteristics of the heavy metal wastewater treatment apparatus according to the present invention.
3 is a view showing data according to the first embodiment of the heavy metal wastewater treatment apparatus of the present invention.
4 is a view showing data according to a second embodiment of the heavy metal wastewater treatment apparatus of the present invention.
5 is a view showing data according to a third embodiment of the heavy metal wastewater treatment apparatus of the present invention.
6 is a diagram showing data according to a fourth embodiment of the heavy metal wastewater treatment apparatus of the present invention.
7 is a view showing data according to a fifth embodiment of the heavy metal wastewater treatment apparatus of the present invention.
8 is a view showing data according to the sixth embodiment of the heavy metal wastewater treatment apparatus of the present invention.
9 is a diagram showing data according to a seventh embodiment of the heavy metal waste water treatment apparatus of the present invention.

Hereinafter, preferred embodiments of the method according to the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user or operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

An apparatus and method for treating heavy metal wastewater according to the present invention will be described with reference to Figs. 1 and 2. Fig.

The heavy metal wastewater treatment apparatus according to the present invention includes a reaction tank 100, a first membrane 201, a second membrane 202, and a third membrane 203. Waste water containing heavy metals is introduced into the reaction tank 100 and treated.

The first membrane 201, the second membrane 202 and the third membrane 203 are located inside the reaction tank 100. The first membrane 201, the second membrane 202 and the third membrane 203 are preferably in the shape of a hollow drum.

When the concentration of the suspended solids in the wastewater flowing into the reaction tank 100 is high, the efficiency of the heavy metal removal treatment by the suspended solids can be lowered, so that the wastewater from which the suspended solids are removed flows into the reaction tank 100. Accordingly, the wastewater to be introduced into the reaction tank 100 can be introduced from the outside into the reaction tank 100 through the first membrane 201. Accordingly, the suspended material in the wastewater flows through the first membrane 201 and is filtered inside the first membrane 201.

The wastewater can be introduced from the outside into the first membrane 201 through a connection pipe connected to the inside of the first membrane 201. The introduced wastewater flows inside the first membrane 201 The outer side of the first membrane 201), and the suspended substances in the wastewater are removed through this process.

However, when the concentration of the suspended solids in the wastewater is low, it goes without saying that the wastewater can flow directly into the reaction tank 100 without passing through the first membrane 201. Therefore, it is preferable that the first membrane 201 is operated according to the concentration of suspended solids in the wastewater.

The compound is filled inside the second membrane 202, and the filled compound is ionized by the water introduced through the pores of the second membrane 202.

After the compound and the water inside the second membrane 202 are ionized, the ions flow out of the second membrane 202 through the pores of the second membrane 202 to form ionic bonds with the heavy metal ions contained in the wastewater This process will be described with reference to FIG.

Water (H ₂ O) in the wastewater flows into the second membrane 202 through the pores of the second membrane 202. The water charged into the second membrane 202 ionizes the compound packed inside. Cations and anions ionized in the cargo and water are discharged into the wastewater outside the second membrane 202 through the pores of the second membrane 202, and the discharged anions are ion-bonded to the heavy metal ions contained in the wastewater. The ion-bound heavy metals are precipitated. The preferred diameter size of the second membrane 202 is at least the diameter size at which water molecules can flow.

The compound may be an alkali metal compound or an alkaline earth metal compound. Preferably, the alkali metal compound is sodium carbonate (Na ₂ CO ₃₎ or may be a sodium hydrogencarbonate (NaHCO ₃₎ carbonate, an alkaline earth metal compound is magnesium (MgO), calcium oxide (CaO) or calcium carbonate (CaCO ₃₎ oxidation days .

A heavy metal wastewater treatment apparatus according to the present invention including a plurality of second membranes 202 and a third membrane 203 will be described with reference to FIG.

The treatment capacity of the reaction tank 100 varies depending on the amount of wastewater to be treated and the size and number of the second membrane 202 may be changed according to the treatment capacity of the reaction tank 100. [ A plurality of second membranes 202 can be uniformly positioned inside the reaction tank 100 in the treatment capacity of the reaction tank 100. Accordingly, there is no need for a separate auxiliary facility required for stirring.

The compound is filled inside the second membrane 202 via a connection tube connected to the inside of the second membrane 202. In the case of treating a large amount of wastewater, the compound can be continuously filled through such a connection pipe, or it may be periodically refilled as if a certain amount is refilled after it is exhausted.

1 and 2 illustrate sodium carbonate (Na ₂ CO ₃ ) or sodium bicarbonate (NaHCO ₃ ), but the present invention is not limited thereto. The compound shown in FIG. 1 and FIG. 2 is a compound capable of ion- Of course it is possible.

The water removed in the reaction tank 100 flows out of the reaction tank 100. The suspended material may remain in the wastewater even when the heavy metal in the wastewater is removed, and it is preferable that the suspended material flows out after the suspended material is removed. The floating material may still remain in the wastewater flowing into the reaction tank 100 as well as the wastewater flowing into the reaction tank 100 through the first membrane 201 as described above.

The third membrane 203 is positioned inside the reaction tank 100 to allow the water removed in the reaction tank 100 to flow out of the water with the suspended substances removed. Unlike the second membrane 202, the third membrane 203 is not filled with the compound. Accordingly, the water in the wastewater flows into the third membrane 203 through the pores of the third membrane 203, and the introduced water flows out of the reaction vessel 100 through a connection pipe connected to the inside of the third membrane 203 Out. During this process, the suspended material is filtered outside the third membrane 203. As with the second membrane 203, the preferred diameter of the pores of the third membrane 203 is at least a diameter greater than the diameter at which water molecules can flow.

The technical characteristics of the first membrane 201, the second membrane 202 and the third membrane 203 located inside the reaction tank 100 will be described.

The wastewater flows into the reaction tank 100 directly through the first membrane 201 or through the pores of the plurality of second membranes 202 located inside the reaction tank 100 Water flows into the second membrane 202. The compound located inside the second membrane 202 is ionized by the introduced water and ions ionized in the compound and water are discharged to the wastewater through the pores of the second membrane 202 to remove heavy metal ions and ions And are precipitated. The water containing no heavy metal is introduced into the third membrane 203 through the pores of the third membrane 203 while the suspended solids remaining in the water are filtered out of the third membrane 203 And the water introduced into the third membrane 203 flows out of the reaction tank 100 through a connection pipe connected to the inside of the third membrane 203.

A batch mode embodiment of a heavy metal wastewater treatment apparatus according to the present invention will be described with reference to FIGS. 3 to 7. FIG.

Hereinafter, a second membrane 202 having a plurality of pores having a diameter of 1 to 5 μm is referred to as a black membrane, and a second membrane 202 having a plurality of pores having a diameter of 0.1 to 1 μm is referred to as a white Membrane. ≪ / RTI >

First Embodiment

The first embodiment will be described with reference to Fig.

In order to investigate the heavy metal removal efficiency according to the pore diameter size, a black membrane and a white membrane were placed in a reaction tank 100 containing wastewater for 1 day, respectively. The filled alkali metal hydride is the same amount of sodium carbonate.

In the case of the black membrane shown in FIG. 3 (a), all the heavy metals were removed until the second batch, but the heavy metal removal efficiency remarkably dropped from the third batch.

In the case of the white membrane shown in Fig. 3 (b), all heavy metals were rapidly removed until the seventh batch, but all the heavy metals were slowly removed from the ninth batch to the twelfth. From the 12th batch, the removal efficiency of heavy metals is seriously degraded.

As a result, a white membrane having a large number of pores having a diameter of 0.1 to 1 m is preferable.

Second Embodiment

The second embodiment will be described with reference to FIG.

In order to investigate the removal efficiency of heavy metals according to alkali metal compounds in a black membrane having a large number of pores having a diameter of 1 to 5 μm, a reaction tank 100 containing wastewater was charged with the same amount of carbonic acid as the black membrane filled with sodium carbonate Each of the black membranes filled with hydrogen sodium was placed for 1 day.

4 (a) or 4 (b) sodium bicarbonate, the removal efficiency of heavy metals is remarkably decreased after the second or third batch.

Third Embodiment

The third embodiment will be described with reference to Fig.

In order to investigate the removal efficiency of heavy metals according to alkali metal compounds in a white membrane having a large number of pores having a diameter of 0.1 to 1 m, sodium carbonate was filled in the reaction tank 100 containing wastewater in the same amount as the white membrane Each of the white membranes filled with hydrogen sodium was placed for 1 day.

In the case of sodium carbonate as shown in Fig. 5 (a), the heavy metal is completely removed up to the 12th batch, although the time is different. From the 13th batch, the removal efficiency of heavy metals is significantly reduced.

In the case of sodium hydrogencarbonate shown in Fig. 5 (b), the heavy metal is completely removed up to the tenth arrangement although the time is different. From the 11th batch, the removal efficiency of heavy metals is significantly reduced.

As a result, in the case of a white membrane, sodium carbonate is preferable as an alkali metal compound to be filled in the second membrane 201.

Fourth Embodiment

The fourth embodiment will be described with reference to Fig.

In the case where the alkali metal compound to be filled is sodium carbonate, in order to investigate the heavy metal removal efficiency according to the residence time of the second membrane 202 in the reaction tank 100, the same amount of sodium carbonate is filled in the reaction tank 100 containing the wastewater The white membranes were placed for 1 day and 2 days, respectively.

In the case of the residence time for one day as shown in FIG. 6 (a), the heavy metal is completely removed up to the twelfth arrangement, although the time is different. From the 13th batch, the removal efficiency of heavy metals is significantly reduced.

In the case of the residence time for 2 days shown in FIG. 6 (b), the heavy metal is completely removed up to the seventh arrangement although the time is different. From the eighth batch, the removal efficiency of heavy metals is significantly reduced.

As a result, when the filled alkali metal compound is sodium carbonate, there is an arrangement in which the heavy metal removal treatment is completely performed even for a short residence time of 1 hour, and the residence time is preferably 1 hour to 24 hours.

Fifth Embodiment

The fifth embodiment will be described with reference to Fig.

In the case where the filled alkali metal compound is sodium hydrogencarbonate, in order to investigate heavy metal removal efficiency according to the residence time of the second membrane 202 in the reaction tank 100, the same amount of sodium hydrogencarbonate was added to the reaction tank 100 containing the wastewater The filled white membrane inside was placed for 1 day and 2 days, respectively.

In the case of the residence time for one day in Fig. 7 (a), the heavy metal is completely removed up to the tenth arrangement although there is a time difference. From the 11th batch, the removal efficiency of heavy metals is significantly reduced.

In the case of the residence time for 2 days shown in Fig. 7 (b), the heavy metal is completely removed up to the seventh arrangement although the time is different. From the eighth batch, the removal efficiency of heavy metals is significantly reduced.

As a result, when the filled alkali metal compound is sodium hydrogencarbonate, there is an arrangement in which the heavy metal removal treatment is completely performed even for a short residence time of 1 hour, and the retention time is preferably 1 to 24 hours as in the case of sodium carbonate.

Sixth Embodiment

The sixth embodiment will be described with reference to Fig.

In order to investigate the heavy metal removal efficiency according to the concentration of the compound, a black membrane filled with sodium hydrogencarbonate was placed in the reaction tank 100 to examine the removal rate of the heavy metal in the first batch.

In the first batch, all heavy metals were removed within one hour. However, as can be seen from FIGS. 3 to 7, it can be seen that the arrangement in which the time for completely removing the heavy metal is more than 6 hours from the arrangement of 3 to 5 is increased, It can be seen that it takes about several minutes.

As a result, according to the results of the examination of the graphs of FIGS. 3 to 8, it can be seen that the removal efficiency (rate) of heavy metal depends on the concentration of the compound to be packed. That is, the higher the concentration, the faster the removal rate, and the lower the concentration, the slower the removal rate. Accordingly, the heavy metal can be completely removed even within 1 hour depending on the concentration of the compound to be packed. It is preferable that the retention time of the second membrane 202 in the reaction tank 100 is about 1 hour to 1 day.

Seventh Embodiment

FIG. 9 shows data of the pH of the wastewater with time after the wastewater is introduced into the reaction tank 100 in a state where the second membrane filled with various compounds is placed in the reaction tank 100. Compounds filled are sodium carbonate, sodium bicarbonate, magnesium oxide, calcium carbonate and calcium oxide. In all the compounds, the pH rises, but sodium carbonate and sodium hydrogencarbonate show the highest rate of increase.

Heavy metals change into different phases depending on their pH. They usually exist in the ionic state at an acidic pH of about 4, and in a neutral state at a pH of 5 or more, they are combined with hydroxides and carbonates to change into a solid state. The solidified heavy metals can be easily removed through sedimentation or filtration, so they are easier to treat than heavy metals in the ionic state.

While the present invention has been described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. It will be appreciated that embodiments are possible. Accordingly, the scope of protection of the present invention should be determined by the claims.

100: Reactor
201: first membrane
202: second membrane
203: third membrane

Claims (11)

A reaction tank 100 into which wastewater flows;
A second membrane 202 in the shape of a hollow drum positioned inside the reaction tank 100; And
And a compound filled inside the second membrane 202,
The compound is refilled from the outside of the reaction tank 100 through a connection pipe connected to the inside of the second membrane 202,
Wherein the compound is any one of an alkali metal compound and an alkaline earth metal compound.
The method according to claim 1,
And a third membrane (203) in the form of a hollow drum located inside the reaction tank (100)
Wherein the water flowing into the third membrane (203) flows out of the reaction tank (100) through a connection pipe connected to the inside of the third membrane (203).
The method according to claim 1,
And a hollow drum-shaped first membrane (201) located inside the reaction vessel (100)
Wherein the wastewater flows into the reaction tank (100) through the first membrane (201).
The method according to claim 1,
The alkali metal compound is sodium carbonate (Na ₂ CO ₃ ) or sodium hydrogen carbonate (NaHCO ₃ )
The alkaline earth metal compound is magnesium oxide (MgO), calcium oxide (CaO) or calcium carbonate (CaCO ₃₎ of heavy metal waste water treatment apparatus.
delete delete (a) introducing wastewater into a reaction tank (100) in which a second membrane (202) and a third membrane (203) having a hollow drum shape are located inside;
(b) filling the inside of the second membrane (202) with a compound; And
(c) water flowing into the third membrane (203) flows out of the reaction tank (100) through a connection pipe connected to the inside of the third membrane (203)
The compound is refilled from the outside of the reaction tank 100 through a connection pipe connected to the inside of the second membrane 202,
Wherein the compound is any one of an alkali metal compound and an alkaline earth metal compound.
8. The method of claim 7,
A hollow drum-shaped first membrane 201 is positioned inside the reaction vessel 100,
In the step (a), wastewater flows into the reaction tank (100) through the first membrane (201).
8. The method of claim 7,
The alkali metal compound is sodium carbonate (Na ₂ CO ₃ ) or sodium hydrogen carbonate (NaHCO ₃ )
The alkaline earth metal compound is magnesium (MgO), calcium oxide (CaO) or calcium carbonate (CaCO ₃₎ the heavy metal oxidation method for treating wastewater.
delete delete

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