KR101046196B1 - Wastewater treatment device and wastewater treatment method using oyster shell and purified sludge - Google Patents

Abstract

The present invention collects the wastewater introduced from the sewage; A primary wastewater treatment tank in which sand, oyster shells and gravel are sequentially filled; And a secondary wastewater treatment tank in which water sludge and gravel are sequentially filled. The primary wastewater treatment tank can be vegetated in the form of wetland of infiltration flow method.

In addition, the present invention is the first step of the waste water introduced from the sewage through the sand, oyster shell and gravel in order to be first purified and the second filtration step in which the first purified waste water is sequentially passed through the water sludge and gravel It relates to a wastewater treatment method comprising a.

The present invention can increase the phosphorus removal efficiency by having a oyster shell and water purification sludge at the same time.

Alum sludge, oyster shell, artificial wetland, phosphorus removal, wastewater treatment

Description

Apparatus and method for treating waste water using a Oyster Shell and a Alum Sludge}

The present invention relates to a water treatment apparatus and a water treatment method having a very high phosphorus removal efficiency by using oyster shell and aum sludge at the same time.

Since domestic sewage or wastewater from various factories is discharged as it is, it causes serious water pollution. Therefore, it must be discharged after removing the pollutants to the extent that natural purification ability can be maintained. In sewage treatment, hardly degradable substances, harmful toxic substances, eutrophic substances and pigment components are not easily removed by the usual methods. Accordingly, various methods have been attempted, and among them, the biofilm method or the adsorption treatment method is known as the best treatment method.

In the biofilm method, microorganisms are attached to the media to increase microorganism residence time under relatively stable conditions, so that various contaminants can be decomposed and removed. The adsorption method mainly removes pollutants by adsorbing pollutants by activated carbon and at the same time providing an environment where microorganisms live. However, in order to treat a large amount of wastewater, the consumption of activated carbon is enormous, resulting in economic problems.

Korean Patent Publication No. 96-28965 discloses a method for preparing a composite adsorbent based on waste powder activated carbon and waste silicate and a wastewater filtration treatment method. This invention recycles powdered activated carbon and waste silicate which are discarded in production plants, such as foodstuffs, to a waste water filtration process by regenerating with a complex adsorbent. In addition, Korean Patent Publication No. 91-22644 discloses a method of using chitosan as a heavy metal adsorbent and a wastewater flocculant.

The conventional wastewater treatment method or the method of the present invention has a function of purifying the wastewater according to each characteristic, but there is a lot of room for improvement in efficiency and economical efficiency, especially in the method of removing phosphorus shows low efficiency.

The present invention is to provide a wastewater treatment apparatus and a wastewater treatment method to increase the efficiency of the removal of contaminants, including phosphorus in the wastewater by using oyster shell and purified sludge together.

The present invention relates to a purified water treatment device and a purified water treatment method for improving phosphorus removal efficiency by using oyster shell and purified water sludge sequentially.

The present inventors use a oyster shell with a high phosphorus adsorption capacity, which can be used for a long time, and an ammonia sludge capable of removing phosphorus quickly and completely, thereby using or not using each of them. Compared to the phosphorus removal efficiency is significantly higher than the present invention was completed.

Specifically, the present invention is a collection tank for collecting wastewater introduced from sewage; The present invention relates to a wastewater treatment apparatus having a primary wastewater treatment tank filled with sand, oyster shells and gravel from the top and a secondary wastewater treatment tank filled with purified sludge and gravel from the top.

In addition, the present invention comprises the steps of: a) first purification of the wastewater introduced from the sewage through the sand, oyster shell and gravel sequentially; And b) a secondary purification step of sequentially passing the first purified wastewater through purified water sludge and gravel; It relates to a wastewater treatment method comprising a.

Hereinafter, the wastewater treatment apparatus of the present invention will be described in more detail with reference to FIG. 1. 1 shows an example of the wastewater treatment apparatus of the present invention, the wastewater treatment apparatus of the present invention, as shown in Figure 1, the purified water sludge (alum) at the rear end of the primary wastewater treatment tank 200 containing the oyster shell It is also possible to include a secondary wastewater treatment apparatus 300 including a sludge, but it is also possible to change the position of the primary wastewater treatment tank and the secondary wastewater treatment tank (not shown). That is, by treating the wastewater flowing into the collection tank first by using a secondary wastewater treatment apparatus including purified water sludge, it can be treated secondly by using a primary wastewater treatment apparatus including a oyster shell at the rear end.

That is, the first aspect is a water collecting tank for collecting wastewater introduced from sewage; The wastewater treatment is connected to the sump, and the wastewater treatment tank is filled with sand, oyster shell and gravel from the top and the primary wastewater treatment tank, and the secondary wastewater treatment tank is filled with purified sludge and gravel from the top. Device.

In addition, the second aspect is a water collecting tank for collecting wastewater introduced from sewage; The first wastewater treatment tank connected to the sump and filled with purified sludge and gravel from the top, and the first wastewater treatment tank connected to the first wastewater treatment tank, the wastewater treatment tank having a secondary wastewater treatment tank filled with sand, oyster shell and gravel from the top. Device.

However, in order to further increase the phosphorus removal efficiency, as shown in FIG. 1, the secondary wastewater treatment apparatus 300 including an aqueous sludge at the rear end of the primary wastewater treatment tank 200 including the oyster shell is included. It is preferable to have a.

As shown in FIG. 1, the primary wastewater treatment tank 200 includes an upper layer filled with sand 230, a middle layer filled with oyster shell 220, and a lower layer filled with gravel 210. The wastewater introduced from the sewage goes to the lower layer from the upper layer of the primary wastewater treatment tank via the collection tank 100, and the primary purification is performed.

In this case, it is preferable in terms of purification efficiency that the oyster shell layer, which is the middle layer, of the upper, middle, and lower layers constitutes the largest content, and more preferably, 50 area% or more of the total capacity of the primary wastewater treatment tank, For example, the water treatment efficiency is higher than 60 to 90 area%.

The primary wastewater treatment tank 200 is in the form of artificial wetland that can be vegetated, the upper sand 230 is provided for the habitat of aquatic plants, the middle layer oyster shell 220 is provided for the adsorption removal of phosphorus. Lower gravel 210 supports the media layers of the upper and middle layers, and is used for catching the bottom.

Sand 230 of the primary wastewater treatment tank 200 is 0.6 ~ 2 mm in diameter, the oyster shell 220 is preferably 0.6 mm ~ 30 mm in diameter, to prevent clogging of the media in the above range It is excellent in the removal effect of phosphorus. The gravel preferably has a diameter of 4 ~ 15mm, less clogging phenomenon in the above range, excellent in the waste water purification ability.

In the present invention, the oyster shell means oyster shell, and washes the oyster shells collected, crushes them after drying, and selects ones that fit the size.

The primary wastewater treatment tank 200 may be provided with a primary supply unit 400 to adjust the flow rate of the wastewater flowing from the collection tank 100 to 0.05 ~ 1 m ³ / (m ² day). In addition, it is preferable that the inflow portion of the wastewater flowing in from the water collection tank is the same height as the upper layer of the primary wastewater treatment tank.

The secondary wastewater treatment tank 300 includes an upper layer filled with the alum sludge 310 and a lower layer filled with the gravel 210, and the purified water sludge 310 has a diameter of 0.6˜. 30 mm, preferably 0.6 to 15 mm, the diameter of the gravel 210 is preferably 4 to 15 mm. In this range, the total nitrogen (TN), total suspended solids (TSS (Total Suspended Solids)) and phosphorus removal ability is excellent.

In the present invention, the water sludge 310 is sludge generated in a water purification plant, and more specifically, aluminum sulfate (Aluminum Sulphate Al ₂ (SO ₄ ) ₃ ) or poly aluminum chloride (Poly Aluminum Chloride) as a flocculant. In the purified water treatment process used, sedimentation basins and backwash water precipitates are dehydrated or dried sludge, crushed and used in the above range.

The secondary wastewater treatment tank 300 may be provided with a secondary supply unit 410 for adjusting the flow rate of inflow of the wastewater purified by the primary wastewater treatment tank to be 0.05 ~ 1 m ³ / (m ² day). have.

The wastewater treatment device is respectively disposed in the primary wastewater treatment tank 200 and the secondary wastewater treatment tank 300 so that the primary wastewater treatment tank 200 and the secondary wastewater treatment tank may be filled with wastewater in order to increase the adsorption efficiency of phosphorus. It is good to make the height of the incoming waste water equal to the height of the outflow water flowing out of the sump.

Next, the wastewater treatment method of the present invention will be described. The wastewater treatment method of the present invention is possible in two aspects. First, the first aspect

a) first clarification of wastewater introduced from sewage through sand, oyster shells and gravel sequentially; And

b) a second purification step of sequentially passing the purified water is purified sludge and gravel;

It relates to a wastewater treatment method comprising a.

Next, the second aspect

a) first purification of the wastewater from the sewage through the purified sludge and gravel sequentially; And

b) a second purification step of sequentially passing the first purified wastewater through sand, oyster shell and gravel;

It relates to a wastewater treatment method comprising a.

The oyster shell and the purified sludge are dried and used after crushing to select the size.

Purification of the first purified wastewater may occur more efficiently when the second purification step of passing through an alum sludge is performed after the first purification step including passing an oyster shell in the purification step.

Hereinafter, the wastewater treatment method will be described in more detail.

In step a), the flow rate of the wastewater introduced from the sewage is 0.05 to 1 m ³ / (m ² day), more preferably 0.1 to 0.6 m ³ / (m ² day), and the residence time of the introduced wastewater ( HRT) is preferably 0.5 to 3 days, preferably 2 to 3 days, and the wastewater can be purified most efficiently in the above range.

The flow rate of the first purified wastewater in step b) is 0.05 ~ 1 m ³ / (m ² day), the retention time (HRT) of the first purified wastewater is 0.1 ~ 1.5 days, more preferably 0.2 ~ One day can be efficiently purged of the first purified wastewater.

The present invention is effective to increase the phosphorus removal rate by treating wastewater using oyster shell and aum sludge.

In addition, the present invention has the advantage that can be more effectively purified by passing the first wastewater treatment apparatus including the oyster shell and the second wastewater treatment apparatus including the purified water sludge secondly.

Hereinafter, examples will be given to illustrate the principles of the present invention. The following examples are only for illustrating the present invention, but the scope of the present invention is not limited thereto.

Example 1

Wastewater Treatment System

The sump was a tank made of polyethylene having a diameter of 1 m and a depth of 1 m. The primary wastewater treatment tank was made of polyethylene, and the lower layer was filled with 10mm of gravel with a depth of 0.15m, the middle layer was filled with oyster shells with a diameter of 0.6mm with a depth of 0.3m, and the upper layer with sand with a diameter of 0.6mm. It was filled with 0.15m, 0.66m in diameter and 0.6m deep.

The secondary wastewater treatment tank was made of polyethylene, and the bottom layer was filled with a 10 mm diameter gravel to a depth of 0.1 m, and the upper layer was filled with a 0.6 mm diameter alum sludge to a depth of 0.2 m. The size of the secondary wastewater treatment tank was 0.63m in width, 0.45m in length and 0.4m in depth.

Wastewater Treatment Method

Wastewater from the sewage was collected into the sump, and the wastewater from the sump was adjusted to a flow rate of 0.1 m ³ / (m ² day) and a residence time (HRT) of 2.5 days, while the sand, oyster shell, The gravel was sequentially passed through to purify it first.

The primary purified wastewater was purified secondly by adjusting the flow rate of 0.13m ³ / (m ² day) and residence time (HRT) to the secondary wastewater treatment tank.

[Example 2]

Wastewater Treatment System

In the above embodiment, the positions of the primary wastewater treatment tank and the secondary wastewater treatment tank are changed so that the wastewater passes first through the secondary wastewater treatment tank in the sump and is purified first, and then passes through the primary wastewater treatment tank to the secondary. Purification was possible. That is, the order of the apparatus was changed so that the wastewater treatment tank with the purified sludge was first called and then purified by passing through the wastewater treatment tank with the oyster shell.

Wastewater Treatment Method

In the above embodiment, the wastewater from the sump was first passed through the secondary wastewater treatment tank to be first purified, and then passed through the primary wastewater treatment tank to permit secondary purification, and the flow rate and residence time of each wastewater treatment tank (HRT ) Is the same as the above embodiment.

Comparative Example 1

Wastewater Treatment System

The sump was a tank made of polyethylene having a diameter of 1 m and a depth of 1 m. The lower layer of a polyethylene tank having a diameter of 0.63m and a depth of 0.6m was filled with 0.3m of gravel having a diameter of 10mm, and filled with 0.3m of sand having a diameter of 0.6mm with the upper layer.

The secondary wastewater treatment tank was made of polyethylene and filled with 10 mm diameter gravel. The size of the secondary wastewater treatment tank was 0.63m in width, 0.45m in length and 0.4m in depth.

Wastewater Treatment Method

Wastewater from the sewage was collected in the sump, and the wastewater from the sump was adjusted to a flow rate of 0.1 m ³ / (m ² day) and a residence time (HRT) of 2.5 days, while sand and gravel were collected in the primary wastewater treatment tank. Sequentially passed through to purify first.

The primary purified wastewater was purified secondly by adjusting the flow rate of 0.13m ³ / (m ² day) and residence time (HRT) to the secondary wastewater treatment tank.

[Test Example]

In Examples 1 and 2 and Comparative Example 1, the degree of contamination of the wastewater, the first purified wastewater and the second purified wastewater of the sump was measured and shown in Table 1 below.

Total nitrogen (TN) of the wastewater, the first purified wastewater and the second purified wastewater of the sump was measured by a total nitrogen analyzer (TN analyzer (Shimadzu, Japan)), and the biological oxygen demand (BOD), Phosphate (PO ₄ -P (ortho-phosphorus)) and total suspended solids (TSS) were measured by the standard method of ' APHA - AWWA - WEF , 1998' .

Table 1

Phosphorus removal efficiency was 99.4 ~ 99.7% when the wastewater treatment device filled with oyster shell and Alum Sludge filtration device were treated as in Example 1 and Example 2, respectively. Likewise, the phosphorus removal efficiency was significantly higher than the case where oyster shell and water purification sludge were not used.

Also, as can be seen from the phosphorus removal efficiency of the first purified wastewater before the second treatment in Examples 1 and 2, the use of only oyster shells or purification using only purified water sludge compared with those used simultaneously. It was found that phosphorus removal efficiency was low.

1 is a view showing an example of a wastewater treatment apparatus according to the present invention.

Description of the main parts of the drawing

100: sump tank

200: Primary wastewater treatment device

210: gravel

220: oyster shell

230: sand

300: secondary wastewater treatment device

310: water purification sludge

400: primary supply unit

410: secondary supply

Claims (10)

A collecting tank for collecting wastewater introduced from sewage; A vertical flow type primary wastewater treatment tank consisting of an upper layer filled with sand, a middle layer filled with oyster shells, and a lower layer filled with gravel, and the wastewater is moved from the upper layer to the lower layer; And A vertical flow type secondary wastewater treatment tank consisting of an upper layer filled with water sludge and a lower layer filled with gravel, and the wastewater flowing from the primary wastewater treatment tank is moved from the upper layer to the lower layer for treatment; Wastewater treatment apparatus having a. delete The method of claim 1, The first wastewater treatment tank is a wastewater treatment apparatus, characterized in that vegetation is possible. The method of claim 3, The sand is 0.6 ~ 2mm in diameter, the oyster shell is 0.6mm ~ 30mm in diameter, the gravel is 4 ~ 15mm in diameter wastewater treatment apparatus. The method according to any one of claims 1 and 3 to 4, Wastewater treatment device to the height of the wastewater flowing into the primary wastewater treatment tank and the secondary wastewater treatment tank is equal to the height of the effluent flowing out of the sump, so that the primary wastewater treatment tank and the secondary wastewater treatment tank is filled with wastewater. The method of claim 1, The purified sludge has a diameter of 0.6 to 30 mm, and the gravel has a diameter of 4 to 15 mm. a) first purification of the wastewater introduced from the sewage, which is sequentially passed through sand, oyster shell and gravel from the top and treated vertically; And b) a secondary purification step of treating the primary purified wastewater in a vertical direction by sequentially passing purified sludge and gravel from the top; Wastewater treatment method comprising a. The method of claim 7, wherein The oyster shell is 0.6mm ~ 30mm in diameter, the sludge is 0.6 ~ 30mm in diameter, the sand is 0.6 ~ 2mm in diameter, the gravel is characterized in that 4 ~ 15mm in diameter. The method of claim 7, wherein Waste water treatment method characterized in that the residence time (HRT) of the wastewater introduced from the sewage in step a) is 0.5 to 3 days. The method of claim 7, wherein Waste water treatment method characterized in that the retention time (HRT) of the first purified waste water in step b) is 0.1 ~ 1.5 days.

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