JPS60139306A - Operation control of filter used in treatment of waste water - Google Patents

Abstract

PURPOSE:To attain the conservation of energy, by filtering only extremely contaminated raw water requiring filtration with due regard to difference in water quality of raw water and bypassing raw water unnecessary to filter without filtering the same. CONSTITUTION:Filtered raw water sent from the preceeding process through a waste water pit 1 is examined by a densitometer 7 and an oil component densitometer 8 attached in the vicinity of a drain port to detect the SS and oil component therein. When the receiving signals of a controller 10 are lower than set values, said controller 10 transmits a stop order signal to a filter pump 3 and a filter 4, and transmits an operation order signal to a bypass valve 11 and a bypass exclusive pump 12. By this mechanism, the operation of the filter pump 3 is stopped to prevent filtered raw water from flowing into the filter 4 and the filtered raw water stored in a raw water tank 2 is directly sent into a treated water tank 6 by the bypass exclusive pump 12 through the bypass valve 11.

Description

[Detailed description of the invention] related.

(Prior Art) Filtered raw water discharged from the previous process is filtered by a filter and passed to a certain water quality standard before being sent to the subsequent process. A normal operation control method of this wastewater treatment filter will be explained with reference to FIG.

That is, the filtered raw water drained from the previous process passes through the drainage pit 1 and is stored in the raw water tank 2. When this storage amount reaches a certain water level, the %p filtration pump 5 starts operating and the filtered raw water is The filtered raw water is sent to the filter 4, where impurities such as %SS (suspended solids) and oil are removed from the filter 4, and after being stored in the treated water tank 5, it passes through the drainage pit 6. The water is sent to the subsequent process.

However, the above method of controlling the operation of a wastewater treatment filter has the following problems.

■ The quality of filtered raw water discharged from the previous process often clears the predetermined water quality standard value even without passing through the filter 4 (though of course this varies depending on the water quality control of the previous process), but as mentioned above, In this operation control method, the entire amount of filtered raw water discharged is filtered by the filter 4 regardless of the quality of the water, so the operation cost of the filter becomes large, resulting in wasted wastewater treatment costs.

(2) Since all of the filtered raw water is passed through the filter 4, the rate of increase in the filtration resistance of one bird becomes faster. As a result, the number of backwashing operations such as backwashing pumps and backwashing blowers increases, which not only increases operating costs for maintenance, but also causes fluctuations in the composition of the R layer due to the increased number of backwashing operations, which impairs the filtration function. There is also a risk of a decline.

(Object of the Invention) In view of the problems of the prior art described above, an object of the present invention is to provide an operation control method for a wastewater treatment filter that eliminates these problems and can save energy. be.

(Structure of the Invention) In order to achieve the above object, the present invention detects the turbidity and oil concentration of filtered water, and when these values are lower than preset values, stops the operation of the filter. , configured to bypass the filter and flow the filtered raw water directly to the treated water tank 7
It is characterized by these points.

(Example) An example of the present invention will be explained based on FIG. In the filtered raw water sent from the previous process through the drainage bit 1, main impurities such as SS and oil are detected by a turbidity meter 7 and an oil concentration meter 8 installed near the drainage port.

The turbidity detected by this turbidity meter 7 is transmitted as a turbidity signal.This turbidity signal corresponds to the turbidity specified by the Water Pollution Control Act, which is the SS of a unit volume. (m+rμ
).

The turbidity signal is sent to the controller 10 via a transducer 9 which converts the turbidity signal into an SS signal. The transmission signal from one oil concentration meter 8 is directly transmitted to the controller 104.

Then, the received signal value sent to the controller 10 is compared with a preset value, and the controller 1071
>A driving command signal or a stop command signal is transmitted to each device.

That is, when the received signal value is higher than the set value, the controller 10 sends the operation command signal to the filter pump 3 and the filter 4.
and sends a stop command signal to the bypass valve 11 and bypass dedicated pump 12 provided between the raw water tank 2 and the treated water tank 5. Then, the filtration pump 3 starts operating, and the filtration raw water stored in the raw water tank 2 is sent to the filter 4. On the other hand, bypass valve 1 is stopped due to the stop command signal.
1 is closed, and the bypass pump 12 remains stopped.
1 Mm of water will not pass through the bypass.

Conversely, if the received signal value of the controller 10 is lower than the set value, the controller 10 sends a stop command signal to the filtration pump 3 and the filter 4.

A driving command signal is transmitted to the bypass valve 11 and the bypass exclusive pump 12. Then, the operation of the filtration pump 5 is 1JI.
To prevent this, the filtered raw water is not sent to the filter 4, and the filtered raw water stored in the raw water tank 2 is sent directly to the treated water tank 6 through the bypass valve 11 by the bypass pump 12.

As described above, the present invention focuses on the difference in the quality of raw water compared to the conventional method of filtering all of the raw water discharged from the previous process.

This is an operation control method that aims to ultimately save energy by passing only raw water that is extremely polluted and needs to be treated, and bypassing raw water that does not need to be treated.

In this first embodiment, an oil concentration meter 8 is attached, but it may not be attached if there is no risk that oil will be mixed with the raw water in the previous process.

In addition, the controller 10 controls ON-OFF of each device.
(In order to prevent frequent repeat operations, it has a timer function that waits for the signal for a certain period of time once a drive command signal or stop command signal is received, and a function that allows the above-mentioned setting values to be changed. be.

The bypass valve 11 has a function that can be automatically opened and closed by an external signal driven by a motor or the like.

In addition, since the pump 12 exclusively for bypass in this embodiment 1 has a smaller pump head due to the pressure loss of the filter 4, the motor capacity is lowered by several ranks than that of the filter pump 5 in order to further increase the energy saving effect. be.

(Effect of the invention) The present invention is constructed as described above.

It has the following effects.

■ It is possible to reduce the operating cost of the p-filter, that is, to save energy.

(2) By shortening the operating time of the 05 filter.

The maintenance costs described in the prior art can be reduced, and the risk of fluctuations in the configuration of FJΔ is reduced, making it possible to extend the period for replacing the 'P blades.

■ Can be applied to existing equipment with minor modifications, requiring smaller equipment.

[Brief explanation of the drawing]

Figure 1 is a diagram of the conventional technology, and Figure 2 is a diagram of the present invention.
It is a figure showing i full. 4...P filter, 5...Treatment water tank (1 idiot)

Claims (1)

[Claims] (1) Detect the turbidity and oil concentration of the filtered raw water, and when these values are lower than preset values, stop the operation of the filter, bypass the FA device, and directly feed the filtered raw water into the treated water tank. A method for controlling the operation of a filter for wastewater treatment, characterized in that the filter is configured to flow.