JP3134177B2 - Operation control method of wastewater treatment plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention purifies raw water (sewage) supplied through a raw water tank and a flow control tank in a treatment tank.
The treatment tank relates to an operation control method corresponding to an abnormal increase in the wastewater treatment plant that discharges the treated water in a run-down manner to the supply amount of the raw water.

[0002]

2. Description of the Related Art FIG. 1 shows a population of about 700 to 800, 200
This is a general flow sheet of a wastewater treatment plant suitable for rural settlements that biologically purifies domestic wastewater of the size of a house. Raw water flowing into the raw water tank 1 from the sewage pipe is pumped into the flow control tank 2 by a pump. increase. Raw water is pumped from the flow control tank to the measuring tank 4
To the treatment tank 5 (in this case, an aeration tank using a blower B) and supply it.
Biological treatment and purification by biofilm. The treated water treated in the treatment tank flows into the sedimentation tank 6 in a downflow manner to the supply amount of raw water supplied from the measuring tank to the treatment tank, and is separated into supernatant water and sludge. The COD is measured by the COD measuring device 10 such as a COD meter and a UV meter, and then flows into the discharge tank 8, where it is pumped and discharged. A part of the sludge is returned from the sedimentation tank to the treatment tank.

In the flow path of the raw water from the raw water tank 1 to the processing tank 5, in the example shown in the figure, an inlet-side flow rate indicator recorder 11 is connected to a pipe for feeding the raw water from the raw water tank to the flow regulating tank.
In addition, an outlet-side flow rate indicator recorder 12 is provided in a pipe for pumping up the treated water to be discharged from the discharge tank. The inlet-side flow meter 11 of the flow-rate indication integrating recorder (also simply referred to as a flow meter) is, for example, one of the raw water fed to the flow rate adjusting tank.
The amount of water supplied every 0 minutes and the amount of raw water supplied for one day are output to a computing unit 9 such as a personal computer or a sequencer via the control panel 3, and the computing unit stores and records these. The outlet-side flow meter 12 calculates the amount of water discharged per hour and the amount of water treated for one day, and the COD measuring device 10 calculates the COD value (mg / litre) via the control panel 3. The calculation unit calculates and calculates the total COD emission per day (kg COD / day). The reason for determining the per day of the total emissions of COD of treated water, depending on the region, treated water a day 50m ³ above, in the facilities such as factories that discharge, the allowable value of emissions per day of COD for each facility This is because it is required to prove that the amount of COD emission per day is below the allowable value, or because COD ≒ BOD × 1.6 to 2.0, the BOD can be estimated by calculation. As a result, instead of finding a BOD that cannot be measured continuously and cannot be obtained without manual analysis, the BOD is estimated by COD to check the processing status, and the amount of air for aeration and return by COD value The purpose is to adjust the amount of sludge and maintain a good and normal operating condition.

The measurement of the COD value is performed by using an expensive outlet flowmeter 1
2 as described in Japanese Patent Application No. Hei 5-299080, the inlet side flowmeter 11, the operation time meter of the pump for pumping to the measuring tank 4, and the COD for measuring the COD of the treated water.
It may be determined by the measuring device 10.

The daily average inflow (Q) of raw water (sewage) flowing into the raw water tank 1 of this wastewater treatment plant is about 240 m ³ , and its normal inflow pattern is as shown by the solid line in FIG. Until around this time, the inflow is almost 0, and the peak of inflow is from 7 am to 10 am, and from 6 pm to 8 am in the evening.
In the daytime, there is a small peak after lunch in the valley between the morning and evening peaks, but at other times, it flows in a lazy way. This normal inflow pattern is repeated every day unless abnormal weather such as torrential rain occurs.

The capacity between the water level H and the water level L of the raw water tank 1 shown in FIG. 3 is about 15 minutes of the time maximum inflow (Qmax) (about 45 minutes of the daily average inflow Q), and Q = 240 m ³ / day. , Qm
If ax = 28.9 m ³ / hour, it is 7.2 m ³ . On the other hand, the capacity between the water level HL of the flow control tank 2 is 6 hours or more of the daily average inflow, generally 6 to 9 hours, and Q = 240.
m ³ / day, 60 m ³ for 6 hours. In the raw water tank, there are two discharge pumps P1 and P1 'which can discharge the wastewater in a short period of time, more precisely, a regular pump which can pump the maximum inflow (Qmax) and a spare water pump. It is provided. The flow control tank 2 has two regular pumps and one spare or one regular and one spare submersible pump P2,
P2 'is provided, and the discharge amount of each of the pumps P2 and P2' can supply more than a daily average amount of sewage because a small amount of raw water is supplied to the treatment tank through the measuring tank and the load on the treatment tank is not increased. And 1/3 to 1/6 of the pump of the raw water tank. In FIG. 3, there is one service pump P2 in the flow rate adjusting tank. The service pump P2 starts operation when the water level reaches 1 m, stops when the water level drops to 0 m L, and the auxiliary pump P2 ' Operation starts when the water level rises to 3.5 mHH, and stops when the water level falls to 3 mH. Raw water tank regular pump P1
Starts operation when the water level reaches 1.5 m, and the water level becomes 0
It stops when it falls to L of m. As described above, since the capacity of the raw water tank is small and the discharge amount of the pump is large, the service pump is repeatedly turned on and off frequently. The preliminary pump P1 'in the raw water tank starts operating when the water level rises to 2.0 mHH, and stops when the water level falls to 1.5 mH. The ANN water level that issues an alarm is 4.5 m for the flow control tank and 2. m for the raw water tank.
5 m.

In the normal flow pattern indicated by the solid line in FIG. 2, as shown by the solid line in FIG. 4, the service pump P2 of the flow control tank starts operation at about 7:00 in the morning when the water level in the tank reaches 1 m. Then, the raw water at the inflow peak in the morning is pumped to the treatment tank until about 2:00 pm, and the raw water at the inflow peak in the evening is pumped into the treatment tank until about 6:00 to 11:00. During operation of the conventional pump P2, since the level of the flow rate adjusting tank does not rise up to 3.5 m, the preliminary pump P2 'is a stopped orゝ, pump P2, P2' the discharge amount of the 20 m ³ / h Then, as shown in the figure, the water supply amount of P2 is 20 m ³ / hour ×
(7 + 5 hours) = 240 m ³ / day, P 2 ′ is 0.
That is, in the normal inflow pattern, a small amount of raw water flowing into the flow control tank is pumped to the processing tank without issuing an alarm or overflowing into the processing tank only by operating the service pump P2. The process is performed.

On the other hand, for example, when it starts to rain from around 11:00 pm on the previous day, heavy rain falls from around 3:00 to around 5:00 in the early morning, and it falls down until around 6:00, it stops for a short time in the raw water tank. The water flows in an abnormal flow pattern shown by the broken line in FIG. That is, the torrential rain from 3:00 to 5:00 appears as an increase in the inflow into the raw water tank from 4:00 to 6:00. The amount of water flowing into the raw water tank from 0:00 to 2:00 is 5 m ³ / h, from 2:00 to 3
The inflow by the hour is 10m ³ / h, and it is 40 from 3 o'clock.
m ³ / h, and from 4 o'clock, a peak is formed at 80 m ³ / h. 60m ³ / h from 5:00, 4 from 6:00
It gradually decreases to 0 m ³ / hour and shifts to a normal inflow pattern from 7:00.

[0009]

In such an abnormal inflow pattern, the raw water tank 1 is immediately filled with the inflowing water, so that the ordinary and spare submersible pumps P1, P1 'are fully operated to pump water into the flow rate adjusting tank. However, the service pump P2 in the flow control tank does not operate unless the water level in the tank reaches 1 m of M and the spare pump P2 'does not operate unless the water level in the tank reaches 3.5 m in HH. As shown by the dashed line, the service pump P2 starts operation at 3:00 when the water level in the tank has reached 1 m, and at 4:30 when the water level in the tank has reached 3.5 m, the backup pump P2 has started.
'Also starts operation. However, these pumps P2, P
Even if the inflow water in the flow rate control tank is sent to the treatment tank by 2 ', the discharge amount is small, so the submersible pumps P1,
P1 'could not keep up with the amount of water sent to the flow control tank, so that the water level in the flow control tank was HH (3.5) at 4:30.
m), an alarm is issued when the ANN water level reaches 4.5 m at 5:00, and when the water level further rises to 5 m, the overflow water level at 5:30, the inflow water is treated with the flow control tank until 6:00. The water overflows from the through hole 13 formed in the upper part of the partition wall of the tank to the processing tank. Assuming that the discharge amounts of the pumps P2 and P2 'are 20 m ³ / hour, the water supply amount by the pumps P2 and P2' is 40 m ³ /hour×5.5/5/6 hours (5 hours 50 hours).
Min) = 233 m ³ , pump P2 water supply amount is 20 m ³ / hour × (16 hours 41 minutes-5 hours 50 minutes) = 20 × 10 hours 51 minutes = 217 m ³ , overflow water amount 10 m ³ , water supply amount and overflow water amount The total is 460 m ³ / day. As described above, when the water level reaches the emergency water level ANN and a warning is issued, the staff of the government office and the maintenance company must go to the site and perform post-processing besides taking immediate measures to deal with the abnormality. In addition, the load on the treatment tank temporarily increases due to the overflow of the raw water from the flow control tank into the treatment tank, causing deterioration in the quality of the treated water, and a sharp increase in the water area load from the sedimentation tank at the latter stage of the treatment tank. As a result, sludge leaks into the treated water, and the quality of the treated water rapidly deteriorates.

[0010]

SUMMARY OF THE INVENTION The present invention utilizes an inlet-side flow meter for storing and recording the flow rate of raw water fed from a raw water tank to a flow rate adjusting tank, which causes an abnormality in a computing unit in the event of a concentrated downpour. 2. The operation control method of the wastewater treatment plant according to claim 1, wherein the occurrence of water is notified, and the computing unit instructs the operation of the pump of the flow control tank which has not reached the operation water level so as to prepare for an increase in rainwater inflow. Supplies raw water to the flow control tank through the raw water tank of the wastewater treatment plant, and supplies the raw water to the processing tank by the ordinary and spare pumps P2 and P2 'which operate according to the water level in the tank from the flow control tank. In the operation control method of the wastewater treatment plant where the raw water is purified in the treatment tank and the treated water is drained from the treatment tank and flows out in a manner to the supply amount from the flow control tank, the raw water supplied from the raw water tank to the flow control tank is controlled. A flow meter that measures and outputs the amount of water supply per hour, An arithmetic unit that receives power is provided, and the arithmetic unit stores the daily amount of raw water that is sent from the raw water tank to the flow rate adjustment tank when the raw water flows into the wastewater treatment plant in a normal inflow pattern. The arithmetic unit compares the actual amount of water supplied from the flow meter with the amount of water transmitted at the same time that stores the amount of water transmitted at the same time. When the water supply amount exceeds a predetermined amount, at least the service pump P2 of the service pumps P2 and P2 'of the flow control tank is operated irrespective of the water level in the tank. It is characterized by pumping water to the treatment tank and lowering the water level in the flow control tank.

In the first aspect, when the amount of water supplied further exceeds a predetermined amount during the monitoring state, at least the service pump P2 of the flow rate control tank is operated regardless of the water level in the tank to pump water into the treatment tank. Only P2 is operated regardless of the water level in the tank to pump water into the treatment tank, and when the amount of water supplied exceeds the stored water supply amount of the arithmetic unit by a predetermined amount, the backup pump P2 'is also operated regardless of the water level in the tank to operate the processing tank. The service pump P2 and the backup pump P2 'are individually and stepwisely operated regardless of the water level in the tank as the water supply increases, and the service pump P2 and the backup pump P2' This includes both the case where the service pump P2 and the spare pump P2 'are simultaneously operated regardless of the water level in the tank due to the increase in the amount of water supply, due to the increase in the amount of water supplied.

According to a second aspect of the present invention, there is provided a method for controlling operation of a wastewater treatment plant, wherein raw water is supplied to a flow control tank through a raw water tank of the wastewater treatment plant, and the normal operation is performed from the flow control tank according to the water level in the tank.
Raw water is supplied to the processing tank by the spare pumps P2 and P2 ', and the raw water is purified by the processing tank.
In an operation control method of a wastewater treatment plant in which treated water flows down from a treatment tank and flows out in a manner, a flow meter that measures and outputs a time-period flow rate of raw water supplied from a raw water tank to a flow control tank and outputs the flow meter. A receiving arithmetic unit is provided, and the arithmetic unit stores a daily amount of raw water supplied from the raw water tank to the flow rate adjusting tank when the raw water flows into the wastewater treatment plant in a normal inflow pattern, for each day, The arithmetic unit compares the actual amount of water supplied from the flow meter with the amount of water transmitted at the same time in which the actual amount of water is stored. It is characterized in that at least the service pump P2 of the pumps P2 and P2 'is operated regardless of the water level in the tank to pump water to the treatment tank and lower the water level in the flow rate adjustment tank.

When the actual water supply exceeds the stored water supply by a predetermined amount, at least the service pump P2 of the flow rate control tank is operated regardless of the water level in the tank to pump water into the treatment tank. Irrespective of the water supply amount in the processing unit, the pump is operated regardless of the water level in the tank to pump the water into the processing tank. Regular pump P2 as water volume increases
And the case where the backup pump P2 'is operated stepwise individually regardless of the water level in the tank.
The two pumps 2 'are operated regardless of the water level in the tank to pump water to the treatment tank.
2 'and 2' are operated simultaneously regardless of the water level in the tank.

[0014]

In the first embodiment, the inlet-side flow meter 11 outputs, for example, the amount of raw water supplied from the raw water tank to the flow control tank every 10 minutes, and inputs it to the computing unit 9 via the control panel. The hourly water supply amount in the normal inflow pattern of raw water into the raw water tank shown by the solid line in FIG. 4 is known, and the water supply amount pattern for 24 hours is similar to the normal inflow pattern into the raw water tank in FIG. Become. Therefore, for example, the operation unit 9 stores the amount of water supplied every 10 minutes output by the inlet-side flow meter in the normal inflow pattern, and compares it with the actual amount of water supplied every 10 minutes output by the inlet-side flow meter 11 for comparison. However, the actual water supply exceeds the stored water supply at the same time in the normal inflow pattern by a predetermined amount, and the state becomes 1
After every 0 minutes, several times, for example, three times (30 minutes), the arithmetic unit enters a monitoring state for monitoring an increase or decrease in the amount of water supplied to the flow control tank.

If the amount of water supply does not increase even after a predetermined time, for example, two hours, has elapsed since the monitoring state, the monitoring is stopped. Conversely, if the amount of water supplied to the treatment tank exceeds the stored amount of water by more than a predetermined amount within two hours after starting monitoring, it is determined that an abnormality has occurred, and at least the regular pump P2 of the flow rate adjustment tank is related to the water level in the tank while continuing monitoring. Drive without. Then, when the amount of water supply shows a decreasing tendency during the operation of the pump, monitoring for stopping the operation of the pump is started, and when the decreasing tendency continues for a predetermined time, for example, two hours, the arithmetic unit switches the operation of the pump to normal control. Return and stop monitoring.

For example, in the normal inflow pattern, from about 0 o'clock when the inflow amount is about 0, the inflow amount of 5 m ³ / h into the raw water tank due to the abnormal inflow pattern shown by the broken line in FIG.
When the inflow rate increases by 5 m ³ / hour every 10 minutes, the amount of water supply from the raw water tank to the flow rate adjustment tank also increases, and the inlet flow meter 11 outputs the amount of water supply to the calculator. . Water amount at 2:30 is stored water amount 0 m ³ / h to 10
When the above m ³ / when the inlet side flow meter is outputted to the computing unit, the computing unit becomes monitoring poised to monitor the increase or decrease of the water supply quantity,
Thereafter, the increase in the water supply amount is known from the inlet side flow meter 11 or the operation signal of the pump of the raw water tank, and if the increase exceeds the stored water supply amount by a predetermined amount, it is determined that there is an abnormality, and the inside of the flow control tank that is not at the operation water level is determined. The operation is commanded to at least the common submersible pump P2 to pump the raw water in the flow control tank to the treatment tank, and to reduce the amount of water in the flow control tank in preparation for rainwater inflow.

FIG. 5 shows this state.
During the monitoring, the inlet water flow meter 11 has input that the amount of water supplied to the flow control tank exceeds the stored amount of water supply of 0 m ³ / hour by 20 m ³ / hour. M (1m)
The operation of the service pump P2 of the flow control tank which has not reached the maximum is started, and the inlet side flow meter measures the stored water flow rate of 0 m ³ / hour by 4 hours.
At about 3:30, when the input of exceeding 0 m ³ / hour is input, the operation is started by the spare pump P2 ′ which has not yet reached the operating water level HH (3.5 m). As described above, the service pump P2 starts operation 10 minutes earlier and the spare pump P2 'starts operation 60 minutes earlier than the conventional method of FIG. 4 to pump water in the flow rate adjustment tank to the treatment tank. The water level in the flow control tank drops. Therefore, even if the raw water mixed with the rainwater of the torrential rain falls into the raw water tank and the submersible pumps P1 and P1 'are fully operated and pumped to the flow control tank, the water in the flow control tank does not overflow from the through-hole 13 to the treatment tank. The maximum water level in the flow control tank is 4.33 m between 6:00 and 7:00, and no alarm is issued because the ANN water level does not reach 4.5 m.

When the amount of water supply starts to decrease at about 4:30, the operation unit is set to a monitoring state of, for example, 2 hours in order to return the operation of the pump to the normal control. Since the decreasing trend has continued, the arithmetic unit stops monitoring that the abnormal inflow situation has ended and stops pump P2.
, P2 'are returned to normal control. At this time, since the water level of the flow control tank is the two operating water levels of the pumps P2 and P2 ', the two pumps continue to operate. At around 9 o'clock the water level dropped, and only the service pump P2 was operated. At around 9:30, the water level of the flow control tank rises and the two units P2 and P2 'are operated. However, the operation amount is not abnormally large as compared with the amount of water stored in the operation unit. When the water level drops at around 10:20, the backup pump P2 'stops operating. After 6:30 when the monitoring is stopped in this way, the pumps P2 and P2 'of the flow control tank are operated under almost normal control. During the monitoring operation in which the operation of the pump is returned to the normal control, when the water supply amount increases abnormally and exceeds the stored water supply amount by a predetermined amount, the monitoring is updated and the operation of the pumps P2 and P2 'is restarted. Incidentally, when the discharge amount of the pump P2, P2 'and 20 m ³ / hr, water of the pump P2 is 20 m ³ / hour × 16 hours 50 minutes = 336.6m ^3, water supply amount of P2' is 20 m ³
× 6 hours 10 minutes = 123.4m ^3, water total amount 460m
³ / day.

In the above-described control, the arithmetic unit enters the monitoring state at about 2:30, and the water supply exceeds the stored water supply of 0 m ³ / hour by 20 m ³ / hour at about 2:50 during the monitoring state. Received from the inlet side flow meter, the ordinary pump P2 of the flow control tank was operated, and at around 3:30, when the input indicating that the water supply amount exceeded the stored water supply amount of 0 m ³ / hour by 40 m ³ / hour. Then, the auxiliary pump P2 'is also operated, and the ordinary pump P2 and the auxiliary pump P2' are operated stepwise in accordance with the increase of the water supply amount. However, there are 2 under surveillance
At about 50 minutes, water amount storage water quantity 0 m ³ / hr 20 m ³
When receiving the input of / h / h, the arithmetic unit may simultaneously start the operation of both the normal and standby pumps P2, P2 '. Even in this case, the water level in the flow control tank does not reach the ANN water level. In this case, the cancellation of the monitoring is the same as described in the paragraph 0018.

Thus, the ordinary and spare pumps P2, P2
When the operation of ′ is started at the same time, the raw water in the flow rate control tank is transferred to the treatment tank more than in the case where the operation is started step by step, and the water level of the flow rate control tank is lowered to more effectively cope with an increase in inflow. On the other hand, on the other hand, the flow rate does not gradually increase, but increases at once, adversely affecting the sedimentation / separation effect in the sedimentation tank, and may deteriorate the quality of the treated water. Also, sending the raw water flowing from the raw water pump tank to the processing tank immediately absorbs fluctuations in the amount of inflow into the processing tank and supplies the raw water to the processing tank on average as much as possible. Will be reduced. Therefore, in order to prepare for an abnormal increase in the inflow of rainwater or the like, if it is unavoidable that the quality of the treated water is unavoidable only at this time, the operation of the ordinary pumps P2 and P2 'for the flow rate adjusting tank should be performed simultaneously. If it is said that it is to prevent the deterioration of the quality of treated water as much as possible, the regular
The operation of the spare pumps P2, P2 'may be started in a stepwise manner. In practice, the pumps P2, P2 are used in a stepwise manner in accordance with an increase in the amount of water supplied to the flow control tank.
'Is preferably started.

As described above, according to the first aspect, the flow meter outputs the amount of water supplied to the flow rate adjusting tank to the calculator, and when the value exceeds the stored amount of water stored in the calculator, the calculator increases the water supply. The monitoring system monitors the increase or decrease in the amount of raw water supplied from the raw water tank to the flow control tank to see if a water supply amount has increased. Even if at least the service pump P2 of the regulating tank is not at the operating water level, the operation is started to lower the water level of the flow regulating tank, and the increased water reaches the space for receiving the increased water from the raw water tank. Before forming. Therefore, the increased water is supplied from the raw water tank to the flow control tank, and overflows from the upper through-hole 13 into the treatment tank beyond the adjustment capacity of the flow control tank, and the treated water whose water quality has significantly deteriorated from the sedimentation tank. It is possible to prevent the water from flowing out or the water level in the flow control tank to reach the ANN water level, and an alarm to be issued, so that it is not possible to be followed up. or,
When the auxiliary pump P2 'is started at the same time as the regular pump, a large raw water receiving space can be formed by the flow rate adjusting tank.

Also in claim 2, the inlet side flow meter 11 outputs the amount of water supplied to the flow rate adjusting tank and inputs it to the computing unit 9 through the control panel. The control method according to the second aspect of the present invention is characterized in that the amount of water supplied to the computing unit by the inlet side flow meter exceeds the stored amount of water supplied at the same time stored in the computing unit by a predetermined amount, for example, 20 m ³ / hour. Is to increase or decrease the flow rate of raw water to the flow control tank for a predetermined time,
For example, at the same time as monitoring for 2 hours, at least the regular pump P2 in the flow rate adjusting tank is operated even if it is not at the operating water level.

[0023] FIG. 6 shows the state, water quantity from the raw water tank 50 pm 2 to the flow regulation tank by abnormal inflow pattern shown by the broken line in FIG. 2 as described above is stored water amount 0 m ³ / When the inlet side flow meter outputs that the time exceeds 20 m ³ / hour to the arithmetic unit, the arithmetic unit is in a monitoring state for monitoring the increase or decrease of the water supply amount for a predetermined time, for example, 2 hours, and at the same time, the operating water level M (1 m) 3:30, when the service pump P2 of the flow control tank which has not reached the maximum was started, and the inlet side flow meter input that the water flow rate exceeded the stored water flow rate of 0 m ³ / hour by 40 m ³ / hour. The operating water level HH (3.5
The operation is started by the spare pump P2 'which has not reached m). Thus, as compared with the conventional method of FIG.
10 minutes earlier, and the preliminary pump P2 'starts operation 60 minutes earlier to pump water in the flow control tank to the treatment tank, so that the water level in the flow control tank drops. Therefore, the raw water mixed with the rainwater of the torrential rain enters the raw water tank, and the submersible pumps P1, P1
'Does not overflow from the through-hole 13 to the treatment tank even if the water is pumped into the flow adjustment tank by the full operation.
The maximum water level in the flow control tank is between 6:00 and 7:00.
At 33m, the ANN water level is not 4.5m, so there is no warning.

When the amount of water supply starts to decrease at about 4:30, the arithmetic unit continues monitoring for about 2 hours to return the operation of the pump to the normal control. Since the trend continues, the computing unit stops monitoring that the abnormal inflow situation has ended and stops pumps P2 and P2.
'Is returned to normal control. However, the water level is pump P2, P2
′, The two units continue to operate.
At around 9 o'clock the water level dropped, and only the service pump P2 was operated. At around 9:30, the water level in the flow control tank rises and P2
, P2 ', the backup pump P2' stops operating at about 10:20 when the water level drops. After 6:30 when the monitoring is stopped in this way, the pumps P2 and P2 'of the flow control tank are operated under almost normal control. The amount of water supplied by the pumps P2 and P2 'is the same as that of the first embodiment shown in FIG.

FIG. 7 shows that, at 2:50, when the inlet flow meter outputs that the amount of water supply exceeds the stored amount of water supply of 0 m ³ / hour by 20 m ³ / hour, the arithmetic unit becomes ready for monitoring. , Regular and spare 2 of the flow control tank that has not yet reached the operating water level
This is an embodiment in which the pumps P2 and P2 'are started to operate. In this case, the service pump P2 is 10 minutes earlier than the conventional method of FIG.
Since the operation is started as soon as possible and the water in the flow control tank is pumped to the treatment tank, the water level in the flow control tank falls sufficiently. Therefore, the raw water mixed with rainwater flows into the raw water tank and the pump P1
, P1 'operates at full capacity and water is pumped into the flow control tank, but the water in the flow control tank does not overflow from the through-hole 13 into the processing tank. In addition, since the water level of the flow control tank is about 3.6m from 6:00 to 7:00 at the maximum, it does not reach the ANN water level,
There is no warning.

At around 4:30, when the amount of water supply decreases, monitoring for returning the operation of the pump to normal control is further performed for 2 hours, and at around 6:30, the decrease amount of water supply remains unchanged. Since the situation continues, the computing unit stops monitoring that the abnormal inflow has ended, and returns the pumps P2 and P2 'to normal control. However, since the water levels are the operating water levels of the two pumps P2 and P2 ', the two pumps continue to operate. At about 7:40, the water level dropped, and only the service pump P2 was operated. The subsequent operation of the pump is almost the same as in the embodiment of FIG. Assuming that the discharge rate of the pumps P2 and P2 'is 20 m ³ / hour, P2
Is 20 m ³ / hour × 16 hours 50 minutes = 336.6
m ³ , P2 ′ is 20 m ³ / hour × 6 hours 10 minutes =
123.4m ^3, water supply total amount is 460m ³ / day.
Whether the operation of the ordinary and spare pumps P2, P2 'is started in a stepwise manner or at the same time is determined in paragraph 0020 by selecting whether to give priority to the quality of the treated water or to give priority to the water level in the flow control tank. What is necessary is just to set as mentioned.

As described above, in the second aspect, the inlet side flow meter outputs the amount of water supplied to the flow rate adjusting tank to the calculator, and when the value exceeds the stored amount of water stored in the calculator for the same time by a predetermined amount. Even if the operation unit does not reach the operation water level, at least the service pump of the flow rate adjustment tank is started to lower the water level of the flow rate adjustment tank, and the increased water is supplied from the raw water tank. The space for receiving the water is formed before the increased water reaches. Accordingly, the increased water is supplied from the raw water tank to the flow rate control tank, and overflows from the upper through-hole 13 into the processing tank beyond the adjustment capacity of the flow rate control tank, and treated water whose water quality is significantly deteriorated from the processing tank. If the water leaks out or the water level in the flow control tank reaches the ANN level, a warning is issued,
This prevents you from being overworked. In addition, when the auxiliary pump P2 'is started at the same time as the ordinary pump, a large raw water receiving space can be formed by the flow rate adjusting tank.

As described above, in the embodiment of the present invention, the raw water is supplied from the raw water tank to the relatively small-sized treatment tank via the flow control tank, and the same amount of the raw water supplied from the flow control tank is drained. The wastewater treatment plant using the activated sludge method discharged from the treatment tank and the biofilm method was explained.However, the treatment tank is a large endless circulation oxidation ditch that is supplied through a raw water tank and a flow control tank. It can also be implemented in wastewater treatment plants.

Although the abnormal inflow pattern has been described in the case of heavy rain, for example, in a resort area such as a ski resort or a beach, sewage flows into a wastewater treatment plant in an abnormal inflow pattern in winter or summer compared to other seasons. I do. In addition, in sightseeing spots, the sewage flows into the wastewater treatment plant on Saturdays and Sundays in an abnormal inflow pattern compared to other days. This abnormal inflow pattern is gentler than the torrential rainfall, but by implementing the present invention at the wastewater treatment plant there, it is also possible to effectively prevent the issuance of an alarm and the deterioration of the treated water.

In each of the embodiments described above, the flow regulating tank has one service pump and one spare pump. However, two service pumps and one spare pump may be used. .

[0031]

According to the method of the first aspect, the inlet side flow meter provided in the pipe from the raw water tank to the flow rate adjusting tank outputs the amount of water supplied to the arithmetic unit at regular time intervals, and the arithmetic unit stores the stored amount of water. Compare and calculate the amount of water supplied at the same time in the inflow pattern, and if the actual amount of water supplied exceeds the stored amount of water by a predetermined amount, abnormal water increase may occur. If the amount of water supply exceeds the stored amount of water supply, it is determined that an abnormality has occurred.
Even if the operating water level has not yet been reached, the operation is started to lower the water level in the flow control tank. Therefore, the water level in the flow control tank is sufficiently low when the regular and spare raw water pumps with large discharges from the raw water tank pump rainwater into the flow control tank. (ANN), so that the treatment plant does not generate an alarm, so that the staff of the government office and the maintenance company do not need to take measures for the abnormality. Furthermore, since a sudden increase in water area load in the sedimentation tank due to overflow from the flow rate adjustment tank to the treatment tank is eliminated, it is possible to prevent a sharp deterioration in the quality of treated water. If the tendency to increase water is no longer observed within 2 hours from the start of monitoring, the operation proceeds as usual, and water is sent to the treatment tank after it has been sufficiently conditioned in the flow rate adjustment tank. In comparison, the stability of the process is higher.

A method according to claim 2 is characterized in that the inlet side flow meter provided in the pipe from the raw water tank to the flow rate adjusting tank outputs the water supply amount to the arithmetic unit at regular time intervals, and the arithmetic unit stores the stored normal inflow pattern. Comparing with the water supply amount at the same time at the same time, monitor the increase or decrease of the water supply amount from the raw water tank to the flow rate adjustment tank if the actual water supply amount exceeds the stored water supply amount by a predetermined amount and abnormal water increase may occur. , And at least a common pump P in the flow control tank
2 Start operation even if the operating water level has not yet reached, and lower the water level in the flow control tank. Therefore, the water level in the flow control tank is sufficiently low at the stage when the regular and spare raw water pumps with large discharges from the raw water tank pump rainwater into the flow control tank. (ANN), so that the treatment plant does not generate an alarm, so that the staff of the government office and the maintenance company do not need to take measures for the abnormality. Furthermore, since there is no sharp rise in water area load due to overflow from the flow rate adjustment tank to the treatment tank, it is possible to prevent a sudden deterioration in the quality of treated water.

According to the operation control method of the first aspect, the amount of treated water can be averaged and the deterioration of the quality of treated water can be reduced as compared with the second aspect.

According to the operation control method of the second aspect, the quality of the treated water is worse than that of the first aspect, but the control is simple, and when the initial inflow amount is large, the action can be taken more quickly than the first aspect. it can.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a first embodiment of the present invention.

FIG. 2 is a diagram showing a normal inflow pattern for one day into a raw water tank and a certain abnormal inflow pattern.

FIG. 3 is an enlarged sectional view of a raw water tank and a flow rate adjusting tank in FIG. 1;

FIG. 4 shows the state of water supply from the flow control tank to the treatment tank (the operation status of the pumps P2 and P2 ') and the fluctuation of the water level in the flow control tank in the normal inflow pattern of FIG. 2 and the abnormal inflow pattern by the conventional method. In the figure, the number in parentheses in the portion indicating the water level of the flow control tank indicates the water level in the flow control tank, and the number outside the parentheses indicates the amount of water.

FIG. 5 is a view showing a state of water supply from the flow control tank to the processing tank and a fluctuation of a water level in the flow control tank when the claim 1 of the present invention is carried out in the abnormal inflow pattern of FIG. The number in parentheses in the portion indicating the water level of the tank indicates the water level in the flow control tank, and the number outside the parentheses indicates the amount of water.

FIG. 6 is a diagram showing a state of water supply from the flow control tank to the treatment tank and a change in water level in the flow control tank according to the first embodiment of the present invention in the case of the abnormal inflow pattern of FIG. The number in parentheses in the portion indicating the water level of the flow control tank indicates the water level in the flow control tank, and the number outside the parentheses indicates the amount of water.

FIG. 7 is a diagram showing a state of water supply from the flow control tank to the treatment tank and a change in the water level in the flow control tank according to the second embodiment of the present invention in the case of the abnormal inflow pattern of FIG. The number in parentheses in the portion indicating the water level of the flow control tank indicates the amount of water in the flow control tank, and the number outside the parentheses indicates the water level.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw water tank P1 Raw water tank regular pump P1 'Raw water tank preliminary pump 2 Flow rate regulating tank P2 Flow rate regulating tank regular pump P2' Flow rate regulating tank preliminary pump 3 Control panel 4 Measuring tank 5 Processing tank 6 Precipitation tank 7 Sterilization tank 8 Discharge tank 9 Computing device (PC, sequencer) 10 COD measuring device 11 Inlet side flow meter 12 Outlet side flow meter

Claims (2)

(57) [Claims] 1. Raw water is supplied to a flow control tank through a raw water tank of a wastewater treatment plant, and the raw water is supplied from the flow control tank to the treatment tank by ordinary and spare pumps P2 and P2 'which operate according to the water level in the tank. In the method of controlling the operation of a wastewater treatment plant that supplies and purifies raw water in a treatment tank and discharges treated water from the treatment tank in a draining manner to the supply amount from the flow control tank, water is sent from the raw water tank to the flow control tank. A flow meter that measures and outputs the flow rate of raw water every hour and an arithmetic unit that receives this output is installed.The arithmetic unit has a flow rate from the raw water tank when raw water flows into the wastewater treatment plant in a normal inflow pattern. The amount of raw water supplied to the regulating tank for each day is stored for each hour, and the computing unit compares the actual amount of water supplied from the flow meter with the amount of water transmitted at the same time and stores the actual amount of water supplied. When the amount of water supplied from the raw water tank exceeds the stored amount When the flow rate is further increased by a predetermined amount, at least the service pump P2 of the service and spare pumps P2 and P2 'of the flow control tank is operated regardless of the water level in the tank. An operation control method for a wastewater treatment facility, comprising pumping water into a tank and lowering the water level in the flow rate adjusting tank. 2. Raw water is supplied to a flow control tank through a raw water tank of a wastewater treatment plant, and the raw water is supplied to the treatment tank by ordinary and spare pumps P2 and P2 'operating from the flow control tank according to the water level in the tank. In the method of controlling the operation of a wastewater treatment plant that supplies and purifies raw water in a treatment tank and discharges treated water from the treatment tank in a draining manner to the supply amount from the flow control tank, water is sent from the raw water tank to the flow control tank. A flow meter that measures and outputs the flow rate of raw water every hour and an arithmetic unit that receives this output is installed.The arithmetic unit has a flow rate from the raw water tank when raw water flows into the wastewater treatment plant in a normal inflow pattern. The amount of raw water supplied to the regulating tank for each day is stored for each hour, and the computing unit compares the actual amount of water supplied from the flow meter with the amount of water transmitted at the same time and stores the actual amount of water supplied. If the amount of water supplied exceeds the stored amount of water by a predetermined amount, the flow control tank is A method for controlling the operation of a wastewater treatment plant, characterized in that at least the service pump P2 among the pumps P2 and P2 'is operated regardless of the water level in the tank to pump water into the treatment tank and lower the water level in the flow control tank.