JP3830781B2 - Maintenance method for oil odor detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oily odor detector, and more particularly to a maintenance method for an oily odor detector that removes and removes an oily odor detector at an appropriate timing in a water intake plant such as a water purification plant.
[0002]
[Prior art]
When river water containing hydrocarbon-based oil flows into a water purification plant, it is necessary to input a large amount of activated carbon to remove the oil. Therefore, at the water purification plant, the oil containing oil is not contained in the river water before the intake. Judgment is made based on the presence or absence of oily odor by the odor detection device, and when oily odor is detected, an alarm is issued immediately and water intake is stopped. For example, Japanese Patent Application Laid-Open No. 11-295203 proposes a management method for the presence or absence of an oily odor using a quartz vibrator sensor for river water flowing into a water purification plant.
[0003]
The quartz oscillator sensor has an ability to selectively detect an oily odor emitted from hydrocarbon oils such as light oil, kerosene, and heavy oil. Therefore, this quartz crystal sensor can detect only the oily odor from the miscellaneous odors even when the river water emits various odors other than oily odor, so it can detect the mixing of hydrocarbon oil into the river water. it can.
[0004]
FIG. 7 is a schematic configuration diagram showing a configuration of a general oil odor detection device, and shows a cleaning and desorption processing state. The sampled water sampled as the fluid to be measured is fed to the purge device 2 through the electromagnetic three-way valve 1 and the piping, and the oil component contained in the sample water is vaporized. The gas to be measured passes through the pipe and is sent to the crystal resonator sensor 3 which is an oily odor detection sensor, and the presence or absence of oily odor is determined. The temperature control device 4 controls the temperature of the gas to be measured and the crystal resonator sensor 3 to a constant temperature in order to remove the influence of the temperature drift of the crystal resonator sensor 3 and increase the accuracy. 5 is an electromagnetic three-way valve.
[0005]
When the oily odor component is adsorbed, the change in the resonance frequency of the crystal resonator sensor 3 is reduced. This resonance frequency change is detected and output as the odor intensity of the oily odor. FIG. 8 is a graph showing a typical example of the response of the oily odor detected by the quartz vibrator sensor 3 in the oily odor detection apparatus of FIG. The vertical axis represents the odor intensity detected by the quartz oscillator sensor, the horizontal axis represents the elapsed time, and g represents the odor intensity curve. A is the time when the oil component is mixed into the sample water (in other words, the oil odor is generated in the gas to be measured), and B is the deodorization time when the oil component is sufficiently removed from the sample water. Show. The odor intensity is detected by a quartz vibrator sensor that selectively detects only the oily odor, and thus becomes the oily odor intensity.
[0006]
Presence / absence of oily odor and detection of oily odor are performed based on the response of oily odor and the temporal change of odor intensity of oily odor. That is, the detection of oil odor and the absence of oil odor are determined based on the time characteristic of the rising edge of the oil odor signal and the time characteristic of the falling edge of the oil odor signal. Further, as is clear from FIG. 8, although the change (rise) at the time point A is slow, it is possible to recognize the start time of the change with care, but the change (decrease) after the time point B is Compared with the change (increase) from A, it is more gradual, and the determination of the deodorization time becomes extremely difficult.
[0007]
Conventionally, when it is determined that deodorization (oil odor has been eliminated), the electromagnetic three-way valve 1 is switched to cleaning water in FIG. In general, air is sent to clean the sensor, that is, to desorb the adsorbed gas. For this reason, if the judgment of deodorization is delayed, there are problems such as the pipes becoming dirty and it takes time to detach and the maintenance is troublesome. Furthermore, there is a possibility that the reliability of oil odor detection of the sensor 3 may be reduced due to dirt in the pipe.
[0008]
[Problems to be solved by the invention]
As can be seen from FIG. 8, the detection of the presence or absence of the oily odor by the quartz vibrator membrane sensor is relatively easy, but it is extremely difficult to detect the odor and the absence of oily odor. In the conventional maintenance method in which cleaning and desorption are started at the determined stage, there is a problem that if the determination of no oily odor is delayed, the piping becomes dirty and it takes time until desorption, and maintenance is troublesome.
[0009]
The present invention has been made to solve the above-described problems, and can quickly and reliably determine oil odor detection so that the piping and / or oil odor detection sensor can be cleaned and desorbed without delay. Thus, an object of the present invention is to provide a maintenance method for an oily odor detection apparatus that can reduce contamination of piping and / or an oily odor detection sensor and can be easily maintained.
[0010]
[Means for Solving the Problems]
The first method of the maintenance method of the oily odor detection apparatus of the present invention comprises an oily odor detection sensor for detecting an oily odor contained in the fluid to be measured, and a pipe for supplying the fluid to be measured to this, When the detected oil odor intensity reaches a predetermined first detection level for determining oil odor detection , an alarm is issued, and when the alarm reaches the predetermined second detection level that exceeds the predetermined first detection level Thus, cleaning of the pipe and / or the oily odor detection sensor is started .
[0011]
The second method of the maintenance method of the oil odor detection apparatus of the present invention is capable of selectively detecting the oil odor contained in the fluid to be measured, but the first oil odor detection sensor having a slow response and a quick response. A second oil odor detection sensor having low selectivity, and a pipe for supplying the fluid to be measured to the second oil odor detection sensor. After the oil odor is detected by the first oil odor detection sensor, the second oil odor detection sensor When the absence of oily odor is detected, cleaning of the pipe and / or the oily odor detection sensor is started.
[0012]
According to a third method of the maintenance method of the oily odor detection apparatus of the present invention, in the second method, when the detection output of the first oily odor detection sensor continues for a predetermined time at a predetermined level or more, the oil odor detection is performed. It is a thing.
[0013]
According to a fourth method of the maintenance method of the oil odor detection apparatus of the present invention, in the second method, the detection output of the first oil odor detection sensor is equal to or higher than a predetermined level, and the detection of the second oil odor detection sensor is performed. Oil odor detection is performed when the output is above a predetermined level.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 relates to the maintenance method of the oil odor detection apparatus according to Embodiment 1 of the present invention, and shows the response of the oil odor detected by the quartz vibrator sensor 3 which is an oil odor detection sensor and the temporal change of the oil odor intensity. It is a graph. The vertical axis represents the oil odor intensity detected by the quartz vibrator sensor, the horizontal axis represents the elapsed time, g ₁ represents the oil odor intensity curve when the first embodiment is applied, and g _0. These are oil odor intensity curves when the piping and the quartz vibrator sensor 3 are not washed, that is, subjected to the desorption process. L ₁ is the first detection level, L ₂ Is the second detection level, K is the oil odor detection stage, and D is the desorption process start stage.
The crystal resonator sensor 3 has a structure in which, for example, an organic polymer thin film for adsorbing a gas is formed on the surface of the crystal resonator, and the mass change due to the gas adsorption is changed by the change in the resonance frequency of the crystal resonator. What detects oily odor selectively from (ΔF) is used.
[0015]
Next, the operation will be described.
As in the conventional example, the presence or absence of oily odor is detected by the quartz vibrator sensor 3 of the oily odor detecting device having the configuration shown in FIG. Sample water, which is the fluid to be measured, is supplied to the purge device 2 through the electromagnetic three-way valve 1 and piping, and the purge device 2 vaporizes oil components and the like contained in the sample water. It is fed to the quartz crystal sensor 3 which is a detection sensor, and the presence or absence of oily odor is determined. The temperature control device 4 controls the temperature of the gas to be measured and the crystal resonator sensor 3 to a constant temperature, in this case, 50 ° C., in order to remove the influence of the temperature drift of the crystal resonator sensor 3 and increase the accuracy.
[0016]
The determination of the presence of oily odor is made from the response of the oily odor and the time change of the rise of the oily odor odor intensity. In the first embodiment, the detected oily odor intensity is determined to be the oily odor detection as shown in FIG. The first detection level L ₁ and the second detection level L ₂ equal to or higher than the first detection level (In other words, the desorption process start confirmation level is a level at which it can be confirmed that the oil odor is not an error but a substantial oily odor). Then, it is determined that oil odor is detected (with oil odor) when the first detection level is exceeded, and detection of oil odor is completed when the second detection level is exceeded. The cleaning and desorption processes are started.
The first and second detection levels can be determined empirically.
For example, in this case, the first detection level is a detection level of 2 Ton (2-fold dilution) in terms of odor intensity, and the second detection level is a detection level of 1 Ton (1-fold dilution) in terms of odor intensity. The second detection level is about twice the first detection level. The detection level at which the detected oil odor intensity can be confirmed as oil odor detection is (−) 40 to (−) 90 Hz (Max) in terms of frequency displacement, and the frequency band is about 9 MHz.
[0017]
The cleaning and desorption processing of the piping and the crystal oscillator sensor 3 and the like are performed by switching the electromagnetic three-way valve 1 and supplying the cleaning water to the purge device 2 through the piping instead of the sample water and switching the electromagnetic three-way valve 5 This is performed by feeding cleaning air into the child sensor 3. When the sensor 3 is washed, that is, when the adsorbed gas is desorbed, the temperature can be increased quickly and controlled to an appropriate temperature and humidity.
[0018]
In the first embodiment, an oil odor alarm is issued at the first detection level stage where it is determined that oil odor is detected, and it is not a stage at which it is determined that the deodorization or oil odor has run out. In addition, cleaning and desorption are started at the second detection level where it can be confirmed that there is a considerable oily odor. By performing cleaning and desorption at an earlier timing, it is possible to reduce the contamination of the piping, the maintenance cycle becomes longer, and oil odor detection with excellent maintainability becomes possible. It is responsive and can reduce the detection time and desorption time of oily odors, prevent deterioration of sensor reliability due to dirt in the piping, and improve reliability.
[0019]
Reference Example 1
FIG. 2 is a graph showing the response of the oily odor detected by the quartz vibrator sensor 3 according to the maintenance method of the oily odor detection apparatus of Reference Example 1 and the temporal change of the oily odor intensity. The vertical axis represents the oil odor intensity detected by the quartz resonator sensor, the horizontal axis represents the elapsed time, g ₂ represents the oil odor intensity curve when the first embodiment is applied, and g _0. These are oil odor intensity curves when the piping and the quartz oscillator sensor 3 are washed, that is, not subjected to the desorption process. L is the oil odor detection level, K is the oil odor detection stage, D is the desorption process start stage, and t is the oil odor detection level duration from the oil odor detection stage K to the start of the desorption process.
[0020]
In the first embodiment, the first detection level for determining the detection of oily odor and the second detection level for starting the desorption process are divided into levels, but in Reference Example 1 , the detected oily odor is shown in FIG. The time is measured by a timer at the stage K when the strength reaches or exceeds the predetermined oil odor detection level determined as oil odor detection, and the oil odor intensity above the oil odor detection level continues for a predetermined time (t) or more, for example, for several minutes. In step D, the detection of the oily odor is stopped, and cleaning of the piping, the crystal resonator sensor 3 and the like is started. When the oil odor intensity equal to or higher than this oil odor detection level continues for a predetermined number of minutes, it is recognized that there is an oil odor.
The presence or absence of oily odor is detected by the quartz vibrator sensor 3 which is the oily odor detecting sensor of the oily odor detecting device having the configuration shown in FIG. ing.
[0021]
In Reference Example 1, since desorption is started before the stage where it is determined that the deodorization and oily odor are gone, the detection time and desorption time of oily odor can be similarly reduced, and the reliability of the sensor due to dirt in the piping Decrease can be prevented and reliability can be improved .
[0022]
Embodiment 2 FIG.
In the first embodiment, the maintenance method in the oil odor detection apparatus using only the crystal vibration sensor 3 having high selectivity but slow response as the oil odor detection sensor has been described, but in this embodiment 2 , the oil odor is selected. Oil odor of the crystal sensor 3 which is a first oil odor detection sensor which can be detected automatically but is slow in response, and a semiconductor sensor 6 which is a second oil odor detection sensor which is quick in response but low in selectivity A case where a detection sensor is used will be described.
FIG. 3 is a schematic configuration diagram showing a configuration of the oily odor detection apparatus according to the second embodiment, and shows a cleaning and desorption processing state. A semiconductor sensor 6 is provided in series with the crystal resonator sensor 3 and downstream thereof. FIG. 4 is a graph showing an example of the response of odor in the fluid to be measured and the temporal change in odor intensity detected by the oil odor detector shown in FIG. The vertical axis represents the odor intensity detected by the oily odor detection sensor, the horizontal axis represents the elapsed time, g ₃ represents the odor intensity curve obtained by the quartz vibrator sensor, and g ₄ Is an odor intensity curve by a semiconductor sensor, and each time axis is matched.
[0023]
The semiconductor sensor 6 has, for example, a structure in which a metal oxide semiconductor such as a press-formed tin oxide is applied between a pair of white metal alloy wire coils and sintered. What detects odor as a change in the resistance value when the change in thermal conductivity and the change in electrical conductivity due to gas adsorption are viewed from both ends of the white metal alloy wire coil is used.
[0024]
In the present embodiment, the oil odor is generated at the stage A when the odor intensity detected by the crystal resonator sensor 3 starts to rise, and after the oil odor is detected, the odor intensity detected by the semiconductor sensor 6 is suddenly increased. It is determined that the oily odor is extinguished at the stage B that decreases, and cleaning and desorption processing of the piping, the crystal oscillator sensor 3, the semiconductor sensor 6 and the like are started.
Oil odor detection and cleaning operations are the same as in the above embodiment.
[0025]
In this embodiment, the detection of oily odor is performed by the crystal resonator sensor 3 having high selectivity to the oily odor, but the determination of the absence of oily odor (deodorization) is a response that makes it very difficult to determine the point of deodorization. Since it is performed not by the quartz crystal sensor 3 having a slow response but by the semiconductor sensor 6 having a quick response, the determination of deodorization is easy and can be accurately performed without delay. The presence or absence of oily odor can be detected in real time, and the piping and oily odor detection sensors can be cleaned and desorbed without delay. Therefore, dirt on the piping is reduced, maintenance can be performed easily, and the oily odor can be detected with high reliability.
[0026]
Embodiment 3 FIG.
FIG. 5 is a schematic configuration diagram showing a configuration of an oily odor detection apparatus according to Embodiment 3 of the present invention, and shows a cleaning and desorption processing state. In the second embodiment, the semiconductor sensor 6 is provided in series with the crystal resonator sensor 3 and downstream thereof. However, in the third embodiment, the semiconductor sensor 6 is not connected in series as shown in FIG. However, it is provided upstream of the crystal resonator sensor 3 close to the sample water introduction side.
As a result, the detection of no oily odor can be performed earlier in time than the third embodiment, so that cleaning and desorption can be performed earlier.
[0027]
Embodiment 4 FIG.
FIG. 6 is a flowchart showing an oily odor detection determination method according to Embodiment 4 of the present invention. In the second and third embodiments, the detection of the oily odor is determined only by the detection output of the oily odor and the oily odor intensity by the crystal resonator sensor 3, but in the fourth embodiment, as shown in FIG. Oil odor detection when the oil odor detection output (odor intensity) by the quartz vibrator sensor 3 is equal to or higher than a predetermined level, the intensity above the predetermined level continues for a predetermined time or more, and the detection output by the semiconductor sensor 6 is higher than a predetermined level. It is determined. The reliability of oil odor detection is improved.
The determination of the absence of oily odor is performed by the semiconductor sensor 6 as in the second and third embodiments, so that cleaning and desorption processing can be performed without delay, dirt on the piping can be reduced, and maintenance can be performed easily.
[0028]
【The invention's effect】
The first method of the maintenance method of the oily odor detection apparatus of the present invention comprises an oily odor detection sensor for detecting an oily odor contained in the fluid to be measured, and a pipe for supplying the fluid to be measured to this, When the detected oil odor intensity reaches a predetermined first detection level for determining oil odor detection , an alarm is issued, and when the alarm reaches the predetermined second detection level that exceeds the predetermined first detection level Since the cleaning of the pipe and / or the oily odor detection sensor is started, the first step of issuing an alarm when the predetermined first detection level is reached, and the predetermined first of the alarm When a predetermined second detection level exceeding 1 detection level is reached, the second step of starting cleaning of the pipe and / or the oily odor detection sensor is taken, and an alarm and subsequent cleaning with high reliability are performed. The desorption process can be performed at an early timing. To become, piping and / or reduces the contamination of the oil odor sensor may piping and / or reduce the reliability deterioration of the oil odor detection sensor due to contamination of the oil odor sensor.
[0029]
The second method of the maintenance method of the oil odor detection apparatus of the present invention is capable of selectively detecting the oil odor contained in the fluid to be measured, but the first oil odor detection sensor having a slow response and a quick response. A second oil odor detection sensor having low selectivity, and a pipe for supplying the fluid to be measured to the second oil odor detection sensor. After the oil odor is detected by the first oil odor detection sensor, the second oil odor detection sensor Since the cleaning of the pipe and / or the oily odor detection sensor is started at the stage where the oily odor is detected, the determination of the oily odor can be easily performed without delay. In addition to the above effects, the reliability of detection of the presence or absence of oily odor is improved.
[0030]
According to a third method of the maintenance method of the oily odor detection apparatus of the present invention, in the second method, when the detection output of the first oily odor detection sensor continues for a predetermined time at a predetermined level or more, the oil odor detection is performed. As a result, the reliability of oil odor detection is further increased.
[0031]
According to a fourth method of the maintenance method of the oil odor detection apparatus of the present invention, in the second method, the detection output of the first oil odor detection sensor is equal to or higher than a predetermined level, and the detection of the second oil odor detection sensor is performed. Since the oil odor detection is performed when the output is equal to or higher than a predetermined level, the reliability of the oil odor detection is further increased.
[Brief description of the drawings]
FIG. 1 is a graph showing a temporal change in response of oily odor and odor intensity detected by a quartz resonator sensor according to Embodiment 1 of the present invention.
FIG. 2 is a graph showing the response of oily odor detected by the quartz resonator sensor according to Reference Example 1 and the temporal change in odor intensity.
FIG. 3 is a schematic configuration diagram showing a configuration of an oily odor detection apparatus according to Embodiment 2 of the present invention.
4 is a graph showing the response of oily odor (odor) detected by the oily odor detector shown in FIG. 3 and the temporal change in odor intensity. FIG.
FIG. 5 is a schematic configuration diagram showing a configuration of an oily odor detection apparatus according to Embodiment 3 of the present invention.
FIG. 6 is a flowchart showing an oily odor detection determination method according to Embodiment 4 of the present invention.
FIG. 7 is a schematic configuration diagram of a general oil odor detection device.
FIG. 8 is a graph showing temporal changes in odor intensity of oily odor detected by a general crystal resonator sensor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electromagnetic three-way valve 2 Purge device 3 Quartz crystal sensor 4 Temperature control device 5 Electromagnetic three-way valve 6 Semiconductor type sensor.

Claims (4)

An oily odor detection sensor for detecting an oily odor contained in the fluid to be measured, and a pipe for supplying the fluid to be measured to the oil odor detection sensor, and a predetermined first detection for determining that the detected oily odor intensity is an oily odor detection. When the level is reached, an alarm is issued, and when the predetermined second detection level that exceeds the predetermined first detection level at which the alarm is issued is reached, cleaning of the pipe and / or the oily odor detection sensor is started. The maintenance method of the oily odor detection apparatus characterized by having carried out.   A first oil odor detection sensor that can selectively detect an oily odor contained in a fluid to be measured but has a slow response, a second oil odor detection sensor that has a quick response but a low selectivity, and the above-described measurement object A pipe for feeding fluid, and after detecting the oily odor by the first oily odor detection sensor, the pipe and / or the oily odor at the stage where the second oily odor detection sensor detects no oily odor. A maintenance method for an oily odor detection device, wherein cleaning of the detection sensor is started. The maintenance method of the oil odor detection apparatus of Claim 2 made to carry out oil odor detection when the detection output of the said 1st oil odor detection sensor is more than predetermined level and continued more than predetermined time. The detection output of the first oil odor detection sensor is equal to or higher than a predetermined level, and oil odor of claim 2, wherein the detection output of the second oil odor detection sensor is set as the oil odor detection when a predetermined level or higher Maintenance method of the detection device.

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