JP3532094B2 - Monitoring device for water treatment equipment with membrane separation device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an operation management technique for a water treatment facility, and more particularly to a monitoring apparatus for a water treatment facility having a membrane separation device. 2. Description of the Related Art Conventionally, in a water treatment facility as shown in FIG. 6, an inflowing treated water 41 is received in an aeration tank 42, and air is supplied from a diffuser 43 in the aeration tank 42. Biological treatment of the treated water continuously,
The mixed solution 44 in the aeration tank 42 is separated into solid and liquid in a sedimentation tank 45, the supernatant water 46 in the sedimentation tank 45 is discharged out of the system via a discharge tank 47, and the sludge settled and separated in the sedimentation tank 45 is returned to the aeration tank 42. By doing so, the activated sludge is prevented from flowing out of the system, and the sludge concentration in the aeration tank 42 is increased. In such a water treatment facility, various indicators such as pH indicating the state in the tank are measured in order to manage the operation, and the measured data is printed on paper to record the data. It uses a recorder that records data and a data logger that records data as electronic data. Also, at least once a week
In small-scale water treatment facilities where inspections are performed frequently, a simple recorder is used or operation is managed without taking records. In a large water treatment facility, a DO meter, an ORP,
A plurality of sensors such as a meter and a pH meter are installed, and detailed data is recorded to perform detailed operation control. Data recording and operation control are performed using a control device such as a personal computer. On the other hand, in a water treatment apparatus using a membrane separation apparatus as shown in FIG. 7, a membrane separation apparatus 54 is immersed in a biological tank 53 following a flow rate adjustment tank 52 into which water 51 to be treated flows. An aeration device 55 is disposed below the separation device 54, and a permeated liquid outlet system 55, which communicates with the membrane separation device 54 and forms a siphon conduit, is opened below the depth of the discharge tank 56,
The membrane separation device 54 is operated using the natural head based on the liquid level difference between the biological tank 53 and the discharge tank 56 as a driving pressure. In the activated sludge treatment using such a membrane separation device, the activated sludge concentration in the tank can be maintained at a high concentration by solid-liquid separation by the membrane separation device.
It has begun to spread widely because the quality of treated water is stable and maintenance is easy. However, while this method can significantly reduce the management of activated sludge, it requires management of a membrane separation device. [0007] In the membrane separation apparatus, organic substances and inorganic substances adhere to the pores and the like of the membrane as the operation is continued. Dirt is disassembled and cleaned. This membrane cleaning is usually carried out regularly at a frequency of about once every six months to one year, or at any time when the membrane becomes extremely dirty and the filtration resistance of the membrane increases. I have. This determination of membrane fouling is made under operating conditions that maintain a constant flux.
Since the filtration pressure (filtration head) required for filtration increases in proportion to the increase in filtration resistance due to contamination, monitoring is performed by monitoring the filtration head. When the filtration head exceeds the upper limit, membrane cleaning is started. I judge it is necessary. In monitoring the head of the filtered water, the viscosity of the water changes depending on the temperature of the water. [0008] However, the increase in the filtration head is caused not only by the increase in filtration resistance due to contamination of the membrane surface, but also by the increase in flow resistance due to an abnormality in the permeate discharge system for guiding the permeate. In some cases, even though the membrane surface itself is being stained, an increase in filtration head does not occur due to damage to the membrane. [0009] Therefore, even if ad hoc monitoring is performed during maintenance, it is not possible to determine that the current filtered water head is a result of normally reflecting the contamination of the membrane surface, and the operation of the membrane separation device such as the filtered water head is not possible. It is necessary to continuously record the index and judge the contamination of the film surface based on data representing a change over time during the monitoring period. The present invention solves the above-mentioned problem, and records the operating state of a membrane separation apparatus as a history during a monitoring period, and can display a time-dependent change in contamination on the membrane surface as image data. It is an object to provide a monitoring device for a water treatment facility having the device. [0011] In order to solve the above-mentioned problems, a monitoring apparatus for a water treatment facility having a membrane separation apparatus according to the present invention is provided in a water treatment facility in which the membrane separation apparatus is immersed in a tank. The operating state of the membrane separation device is monitored by using the filtered water head measured by a water level gauge or a pressure gauge, the water temperature in the tank measured by a water temperature gauge, and the flow rate of the membrane permeate measured by a flow meter as indexes. An apparatus, comprising: a data recording circuit for recording a measurement value of each index during a preset monitoring period for each set sampling time; and a filtration head stored in the data recording circuit.
And a data display circuit for displaying measured data of flow rate and water temperature in time series, and a control circuit for controlling the data recording circuit and the data display circuit. [0012] Further, a transmission function for transmitting measurement data recorded in the data recording circuit to the outside is provided. Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1 to FIG.
Is a flow control tank 3 for receiving the in-process water 2,
An aeration tank 4 for biologically treating the water 2 to be treated;
, A diffuser 6 disposed below the membrane separator 5, a discharge tank 7 for storing the membrane permeate, and a siphon pipe communicating with the membrane separator 5 to form a siphon pipe. A permeated liquid outlet pipe 8 opened below the depth of the tank 7, a discharge pipe 7a for discharging the membrane permeated liquid from the discharge tank 7 to the outside of the system, and a flow control tank 3
Constant flow pump 9 for supplying water 2 to the aeration tank 4 at a constant rate from the air, and blower 1 for supplying aeration air to the diffuser 6
0, a water thermometer 11 for measuring the water temperature in the aeration tank 4,
A water level gauge 12 provided in the aeration tank 4 to measure the filtered water head acting on the membrane separation device 5 (a pressure gauge may be used, and a water level gauge may be provided in a tank other than the aeration tank depending on the model).
And a flow meter 13 for measuring the flow rate of the membrane permeate in the permeate outlet pipe 8. The monitoring device 14 monitors the operating state of the membrane separation device 5 using the water temperature measured by the water temperature gauge 11, the filtered water head measured by the water level meter 12, and the flow measured by the flow meter 13 as indices. , Water temperature meter 11, water level meter 12, and flow meter 13
, And an output port 16 for outputting data to the outside. The liquid crystal panel P for displaying data on the upper surface and operation buttons 17 are provided. More specifically, the monitoring device 14 includes an A / D interface circuit 18 connected to each input port 15 for performing A / D conversion, a communication interface circuit 19 connected to the output port 16, and an operation button 17. A connected switch circuit 20, a dip switch circuit 20a for performing various initial settings, and an EE for recording setting data.
PROM circuit 21 and ROM for storing basic programs
A circuit 22, a RAM circuit 23 for recording measurement data,
A calendar circuit 24 for outputting time, and a liquid crystal panel 16
, And a CPU 26 for controlling each circuit. In the above configuration, the water 2 to be treated received in the flow control tank 3 is supplied by the constant flow pump 9 from the flow control tank 3 to the aeration tank 4 at a constant rate, and is supplied from the diffuser 6 in the aeration tank 4. Biological treatment with activated sludge in the tank while supplying air. On the other hand, in the membrane separation device 5, since the permeated liquid outlet pipe 8 forms a siphon pipe, the natural water head between the liquid surface in the aeration tank 4 and the liquid surface in the discharge tank 7 is filtered water head (driving pressure). ), The membrane permeate which has passed through the membrane such as the organic filtration membrane flows out to the discharge tank 7 through the permeate outlet pipe 8, while the activated sludge remains in the tank. In the present embodiment, gravity filtration using a natural head is performed, but a filtered head may be provided using a suction pump. At this time, the constant flow pump 9 is connected to the flow control tank 3
And the amount of permeate flowing out of the permeate outlet pipe 8 into the discharge tank 7 antagonizes the flow rate of the water to be treated 2 supplied to the aeration tank 4 from
The liquid level in the aeration tank 4 is located at a liquid level that gives the membrane separation device 5 a predetermined filtered head. If the permeation flux of the membrane in the membrane separation device 5 is reduced due to a change over time due to contamination of the membrane surface or the like, the amount of the membrane permeate flowing into the discharge tank 7 through the permeate outlet pipe 8 is reduced. The liquid level in the aeration tank 4 rises to increase the filtration head, and the increase in the filtration head causes an increase in the amount of membrane permeate, and filtration until the amount of membrane permeate recovers to an amount commensurate with the supply of the constant flow pump 9. The water head increases. The monitoring device 14 includes a water temperature meter 1 in a data recording circuit comprising a CPU 26 and a RAM circuit 23.
1. A voltage input from the water level meter 12 and the flow meter 13 to each input port 15 is input to each A / D interface circuit 18.
And the collected data is stored in the RAM circuit 23 as a measured value. In this measurement, assuming that the liquid level in the discharge tank 7 is constant, a value obtained by subtracting the preset liquid level in the discharge tank 7 from the liquid level in the aeration tank 4 measured by the water level meter 12 is used as a filtered water head. And the measured filtered water head is
Correct based on the water temperature measured in the above, and obtain the filtered head at the standard water temperature. The sampling of measured values is performed by taking in data at one-second intervals, averaging the data every sampling time (for example, 3 minutes), and storing the data during a preset monitoring period (for example, 15 days). The monitoring period is set according to the maintenance frequency of the water treatment equipment 1,
At the time of inspection, it corresponds to the period from the previous inspection to the current inspection. As the measured values, all data during the monitoring period is stored, old data that exceeds the monitoring period is sequentially deleted, and the latest data is added to the stored data. During maintenance, the measurement data stored in the data recording circuit is displayed in chronological order by a data display circuit comprising the CPU 26, the liquid crystal interface circuit 25, and the liquid crystal panel P. As shown in FIG. 4, the display is expressed as a ratio between the date and time H at which the sample was taken and the measured value obtained by the sampling as a percentage. That is, the measured values of the filtered water head, the water temperature, and the flow rate are displayed in a list, and by appropriately operating the operation button 17, the oldest one is displayed in chronological order from the newest one, or the newest one is displayed in chronological order. . When the operation button 17 is operated to switch the display mode to the graph screen, as shown in FIG. 5, the measurement data D during the monitoring period is measured with the X-axis as time and the Y-axis as a measurement value (set in advance). The change is displayed as a graph in chronological order, and the data for each input port, ie, filtered water head, water temperature,
Each measured value of the flow rate is individually displayed, and the data type to be displayed is switched by appropriately operating the operation button 17. The unit of the displayed time axis is the operation button 17.
Can be changed by the operation described above, and the data of the entire monitoring period can be displayed at a time at the maximum. Further, on the screen, the unit M of the time axis, the measured date and time H of the latest data being displayed (the right end on the screen), and the value V of the data are displayed. Therefore, by displaying the data saved at the time of maintenance on the screen, the change of the filtered water head during the monitoring period can be recognized in a time-series manner on the spot, and the current filtered water head can be recognized by the normal temporal change. It is possible to judge whether or not it is caused, and it is possible to judge whether or not the membrane is damaged by checking the change in the flow rate. The stored data is output to the output port 16 through the communication interface circuit 19, and the measured value data is received at a remote place through a modem or the like connected to the output port 16, and the operating state of the membrane separation device 5 is changed. Can be monitored on the ground. As described above, according to the present invention, the change in the filtration head during the monitoring period is recognized in a time-series manner.
It is possible to judge the validity of the filtration head as an indicator of the state of membrane contamination, and to determine the presence or absence of membrane damage by checking the change in flow rate.
The stored data can be recognized at a remote location, and the operating state of the membrane separation device can be monitored at a remote location.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a configuration of a water treatment apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of the monitoring device according to the embodiment. FIG. 3 is a block diagram showing a circuit configuration of the monitoring device according to the embodiment. FIG. 4 is a schematic diagram showing a display screen of the monitoring device according to the embodiment. FIG. 5 is a schematic diagram showing a graph display screen in the monitoring device according to the embodiment. FIG. 6 is a schematic diagram showing a configuration of a conventional water treatment apparatus. FIG. 7 is a schematic diagram showing a configuration of a conventional water treatment apparatus. [Description of Signs] 1 Water treatment device 2 Water to be treated 3 Flow control tank 4 Aeration tank 5 Membrane separation device 6 Diffusion device 7 Discharge tank 8 Permeate outlet pipe 9 Constant flow pump 10 Blower 11 Water temperature gauge 12 Water level gauge 13 Flow rate Total 14 Monitoring device 15 Input port 16 Output port 17 Operation button 18 A / D interface circuit 19 Communication interface circuit 20 Switch circuit 21 EEPROM circuit 22 ROM circuit 23 RAM circuit 24 Calendar circuit 25 Liquid crystal interface circuit 26 CPU

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-126882 (JP, A) JP-A-5-168871 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C02F 1/44

Claims (1)

(57) [Claims] [Claim 1] In a water treatment facility in which a membrane separation device is immersed in a tank, a filtered head measured by a water level gauge or a pressure gauge and a filter head measured by a water temperature meter are used. A device for monitoring the operating state of a membrane separation device using a water temperature and a flow rate of a membrane permeate measured by a flow meter as an index, wherein a measurement value of each index is set for each sampling time during a monitoring period set in advance. a data recording circuit for recording, filtered stored in the data recording circuit
A water treatment apparatus having a membrane separation device, comprising: a data display circuit for displaying measured data of a water head, a flow rate, and a water temperature in a time series, and a control circuit for controlling the data recording circuit and the data display circuit. Equipment monitoring equipment.