KR20040011762A - Pretreatment apparatus of waste water using an aerobic filter tank and its method - Google Patents

Abstract

PURPOSE: Provided are an apparatus and a method for pretreating wastewater, which can pretreat large amount of wastewater in a small area in short time. CONSTITUTION: The apparatus comprises a first anaerobic tank(1) divided into a first zone(5) and a second zone(6) by a partition wall(3) with an opening at a lower portion thereof, and provided with a heater(7) in the first zone(5) for increasing a temperature of the anaerobic tank; and a second anaerobic tank(9) divided into a first zone(10) and a second zone(11) by a partition wall(2) with an opening at a lower portion thereof, and provided with a heater(7) in the first zone(10), wherein the second zone(6) of the first anaerobic tank(1) is connected to the first zone(10) of the second anaerobic tank(9) by a pipe line. The method comprises the steps of introducing wastewater into the first zone(5) of the first anaerobic tank(1); removing suspended solids a time a day from the first zone(5), wherein the introduced wastewater is finally transferred to the second zone(11) of the second anaerobic tank(9) via the second zone(6) of the first anaerobic tank(1) and the first zone(10) of the second anaerobic tank(9); and discharging the wastewater in the second zone(11) of the second anaerobic tank(9) to a bioreactor; and returning decant water of a settling tank to the first zone(5) of the first anaerobic tank(1), wherein the heater(7) heats the wastewater in the first and second anaerobic tanks(1,9) to a temperature of 30 to 35 deg.C, and amount of the returned wastewater is one to two times as much as amount of raw wastewater.

Description

Wastewater pretreatment apparatus using anaerobic filtration tank and its method {PRETREATMENT APPARATUS OF WASTE WATER USING AN AEROBIC FILTER TANK AND ITS METHOD}

The present invention relates to a wastewater pretreatment apparatus using an anaerobic filtration tank and a pretreatment method thereof.

In general, pretreatment of wastewater is carried out in advance, particularly in case of livestock wastewater with high pollution, in order to pretreat it, a large treatment space and a complicated pretreatment facility have been required. Therefore, such pretreatment in farmhouses has a lot of difficulties in treating wastewater such as large livestock wastewater because it takes a lot of area and facility cost and takes a long time to treat.

The present invention has been invented in view of the above, and has developed a device and a method capable of pretreatment of a large amount of wastewater while enabling a simple facility using an anaerobic filtration tank as a pretreatment process.

1 is a view for explaining the configuration of an apparatus according to the present invention;

2 is a bar graph showing the alkalinity fraction compared to the raw water according to the internal conveying amount of the supernatant according to the present invention

3 and 4 are bar graphs showing the item-specific removal rate according to the conveyance amount of the upper water according to the present invention.

5 is an explanatory diagram showing a generation amount of scum and processing thereof;

The main constitution of the present invention includes a partition (2) provided inside and divided into a first end portion (5) and a second end portion (6), and provided so that a constant opening portion (3) is formed in the lower portion, and the first end portion (5) described above. Anaerobic filtration tank (1) including a heater (7) installed in the) to increase the internal temperature; The anaerobic filtration tank (1) is made of the same configuration and is characterized in that it consists of a second anaerobic filtration tank (9) installed in connection with the second end (6) of the anaerobic filtration tank (1), the method described above 1 After the wastewater to be treated is introduced into the end portion 5, the suspended solids floating thereon are removed once a day, and the treated water entering the second end portion 6 through the first end portion 5 is again subjected to the second anaerobic filtration tank. Through the first end 10 and the second end 11 of (9) to enter the biological reactor to be subsequently processed so that the supernatant of the subsequent settling tank is introduced into the first end 5 of the anaerobic filtration tank 1 described above. Characterized in that, the anaerobic filtration tank (1) and the heater (7) installed in the second anaerobic filtration tank (9) is heated so that the treated water temperature is maintained about 30-35 degrees Celsius, and the supernatant of the settling tank the anaerobic The upper amount of water to be returned to one end 5 of the filtration tank 1 is lowered at a flow rate of 1-2 times the amount of raw water. It is characterized by.

Other features and configurations other than those described above will be described in more detail below with the accompanying drawings.

In the present invention, the suspended solids in the raw water is first separated into solids, and an anaerobic filtration tank is operated to remove dissolved organic matter.

The anaerobic filtration tank is primarily intended to remove suspended solids (SS) in raw water and to reduce organic loads, and certain operating conditions must be established for smooth operation of subsequent biological processes.

Anaerobic filtration apparatus according to the present invention was configured as follows

The anaerobic filtration tank 1 was prepared 30 cm wide, 30 cm long, 40 cm high, and an effective dose of 30 liters.

The structure of the anaerobic filtration tank 1 is divided into partitions 2 and is divided into 1, 2 and 5 ends, and the lower end of the partition 2 is about 30 mm open to form an opening 3. . Thus, the raw water 4 flows in from the upper end of the first end 5 of the anaerobic filtration tank 1, passes through the opening 3, which is the cut portion at the lower end, and passes over the second end 6 of the anaerobic filtration tank. In order to obtain higher solid-liquid separation efficiency, one more anaerobic filtration tank was installed and operated in four stages.

At one end 5 of the anaerobic filtration tank 1, a temperature heater 7 was installed to maintain the temperature of the anaerobic microorganism by maintaining the temperature of 30 to 35 degrees Celsius, preferably 32 degrees.

When raw water is injected into the top of the first end 5 of the first anaerobic filtration tank, the SS component is filtered off in some scum layers 12 (SCUM), and the remaining SS and organics are decomposed by anaerobic microorganisms and separated into solid-liquid and some are suspended again As a scum in the state, the mineralized component is deposited at the bottom to form a granulated filtration layer 8 containing a large amount of anaerobes.

The filtered water passing through the filtration layer 8 below the first end 5 and the second end 6 flows into the upper end of the first end 10 of the second second anaerobic filtration tank 9 and performs the same process as the first anaerobic filtration tank. Repeatedly, it is allowed to enter the biological reactor at the end after the end. That is, the treated water that passed through the second anaerobic filtration tank (9) was sent to the anoxic tank, the aeration tank, and the sedimentation tank, and the supernatant of the sedimentation tank was returned to the first stage (5) of the anaerobic filtration tank (1) to promote the activity of the anaerobic filtration tank (1).

The conveyed quantity is 1-2 times the flow volume (1-2Q) of raw water quantity.

The changes in the treated water quality according to the amount of return were examined. The removal rate was as shown in Table 1 when the internal return amount was changed to 0, 1 and 2Q.

Anaerobic Filtration Treatment Internal Return (%) Item 0 100 200 pH inflow 8.4 8.3 8.4 outflow 8.3 8.5 8.3 Alkaline (mg / ℓ) inflow 5400 4400 5600 outflow 3132 5280 8790 % Removal 42.0 -20.0 -57.0 BOD (mg / ℓ) inflow 8040 7800 8700 outflow 265 1510 2080 % Removal 96.7 80.6 76.1 CODCr (mg / L) inflow 15920 18900 14730 outflow 2460 5670 5530 % Removal 84.5 70.0 61.5 SS (mg / L) inflow 3370 3500 4125 outflow 450 550 980 % Removal 86.6 84.3 76.2 T-N (mg / L) inflow 1880 2640 2280 outflow 1230 1600 1590 % Removal 34.6 39.4 30.3 NH3-N (mg / L) inflow 1640 1810 1680 outflow 1240 1420 1330 % Removal 24.4 21.5 20.8 T-P (mg / L) inflow 320 440 410 outflow 220 315 300 % Removal 31.3 28.4 26.8

As shown in Table 1, the BOD decreased from 8,040mg / l to 265mg / l when operating with only the inflow of raw water without internal return, and the removal rate was about 96.7%, and SS was 450mg / l at 3,370mg / l. The reduction rate was about 86.6%, and the CODCr decreased by 2,460 mg / L at 15,920 mg / L, which was about 84.5%.

Therefore, when the operation was performed only by the inflow of raw water without internal conveyance, the removal rate was the best, but as shown in the alkalinity fraction of the raw water according to the internal conveyance amount of FIG. The pH of the biological treatments at was lowered to 5 so that alkaline could not be operated without supplementation.

However, it can be seen that the alkalinity increases as the sediment supernatant is returned to the anaerobic filtration tank. As shown in FIG. 2, the pH increased by 10-27% in 1Q and 52-69% in 2Q. It was maintained as above and stable water treatment was possible.

Also, as shown in FIG. 3, the removal rate of BOD according to 1Q and 2Q conveyance amounts to about 76-81%, CODCr 57-68%, and SS 70-84%. As the conveyance rate increases, the removal rate decreases. . It is thought that this is because the residence time is shortened as the return rate increases.

However, anaerobic filtration tanks are installed and operated as a pretreatment concept rather than a final treatment, so it is considered sufficient to reduce the loads of organic materials and SS treatments that are subsequently processed. .

In addition, as shown in Figure 4, the removal rate of nitrogen in the anaerobic filtration tank is a low state of about 30-35%, the difference in removal rate according to the return rate was also very small.

This is because the ratio of ammonia nitrogen, which is dissolved nitrogen, is relatively low at 68.6%.

In the case of phosphorus, the removal rate was low (about 20-30%), and there was little difference in the removal rate according to the return rate.

The following describes the amount of scum generation and its processing method.

The SS component entering the anaerobic filtration tank will contain suspended solids in raw water, excess sludge for disposal in subsequent activated sludge processes, and suspended solids in the settling supernatant returned.

Referring to FIG. 5, the amount of SS introduced in one day is 36-45g in 10L of raw water, 7-21g in 1-3L of excess sludge, and 0.7-1.4g in 10-20L of settling tank supernatant returned. 67.4 g, and the amount of SS flowing out was 6.8-10.7 g in the flow rate of 21-33 L of 10 liters of raw water, 10-20 liters of sedimentation tank supernatant and 1-3 liters of surplus sludge, resulting in a theoretical accumulation of 30.7-57.7. g.

In fact, the amount of SS removed by scum was 12-30 g, accounting for about 52% of the accumulated stock, the concentration of scum was 60,000-150,000 mg / l, the water content was 85-94%, and the extraction amount was 150-250 ml. It can be seen that scum generation increases in proportion to the concentration of SS in the raw water.

The moisture content was also lowered in proportion to the SS concentration. The theoretical accumulation of SS is about 48% of the inflow minus the scum removal, and no excessive rise in sedimentary sedimentary deposits was observed during reactor operation for 6 months. This is because much of the sludge accumulated by anaerobic microorganisms has been digested.

According to the above-described processing, when 10 liters of raw water enters and 20 liters of return water enters, for example, 30 liters equal to the capacity of the anaerobic filtration tank 1 is obtained. And 10 l of raw water and 20 l of return water will be filled up to the second anaerobic filtration tank 9 of the same capacity. The initial incoming raw water then takes about two days to be processed theoretically, resulting in very rapid bulk treatment. However, it was found that the most efficient treatment was to adjust the inflow wastewater to be about 5 days before and after the final second anaerobic tank (9) for sufficient pretreatment.

According to the present invention as described above, even after scum removal at the top of the anaerobic filtration tank once a day and partial bottom sludge removal once or twice a quarter, it is possible to operate the subsequent biological process normally without the need for a pretreatment facility such as a dehydrator and a centrifuge. there was

In addition, according to the present invention, the very fast operation treatment by the anaerobic filtration tank can be seen almost the same pre-treatment effect as in the prior art, there is an advantage that can increase the wastewater treatment efficiency extremely.

In addition, it does not occupy a lot of land area for wastewater treatment, and it is easy to install additionally in existing facilities, for example, to effectively eliminate the plant overload caused by the expansion of livestock houses.

It also has the advantage of composting scum or sludge to be removed.

Claims (3)

A partition (2) installed inside and partitioned into a first end portion (5) and a second end portion (6) and having a constant opening (3) formed at the lower portion, and installed in the first end portion (5) described above An anaerobic filtration tank (1) comprising a heater (7) to raise the temperature; A wastewater pretreatment apparatus using an anaerobic filtration tank, which is made of the same structure as the anaerobic filtration tank (1), and is composed of a second anaerobic filtration tank (9) installed to be connected to the second end (6) of the anaerobic filtration tank (1). A partition (2) installed inside and partitioned into a first end portion (5) and a second end portion (6) and having a constant opening (3) formed at the lower portion, and installed in the first end portion (5) described above An anaerobic filtration tank (1) comprising a heater (7) to raise the temperature; Made of the same structure as the anaerobic filtration tank (1), the interior is composed of the first end 10 and the second end (11) and at the same time is installed and connected to the second end (6) of the anaerobic filtration tank (1) In the method of treating wastewater using a wastewater pretreatment device comprising an anaerobic filtration tank (9), After the wastewater to be treated is introduced into the first end portion 5, the suspended solids suspended in the upper portion are removed once a day, and the treated water introduced into the second end portion 6 through the first end portion 5 is again removed. 2 The first stage 10 and the second end 11 of the anaerobic filtration tank 9 enter the biological reactor to be processed subsequently, and the supernatant of the subsequent sedimentation tank is introduced into the first stage 5 of the anaerobic filtration tank 1 described above. Wastewater pretreatment method using an anaerobic filtration tank characterized in that The method of claim 2, The heater 7 installed in the anaerobic filtration tank 1 and the second anaerobic filtration tank 9 is heated to maintain a treated water temperature of about 30 to 35 degrees Celsius, and the supernatant of the settling tank is the anaerobic filtration tank 1. Wastewater pretreatment method using an anaerobic filtration tank, characterized in that the amount of supernatant to be returned to one end 5 of the tank is 1-2 times the amount of raw water.