JPH0475459B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to an automatic continuous flash point measuring device and a measuring method for automatically and continuously measuring the flash point of petroleum, etc. [Prior Art and Problems to be Solved by the Invention] As a method for measuring the flash point of kerosene, light oil, etc. obtained in the distillation process of petroleum, the method specified in JIS is known. However, this method is cumbersome to operate and cannot measure the flash point continuously.
Although it is suitable for accurately determining the flash point in the laboratory, it is not very suitable for use in factories. For this reason, conventional flash point measuring devices suitable for use at factory sites include a flash point measuring device, a sample heating device installed in the device, and a sample temperature measuring device inside the device. , an ignition electrode disposed in a discharge space in the upper part of the device main body, a discharge power supply connected to the discharge electrode, and an oxygen-containing gas supply mechanism that supplies oxygen-containing gas to the discharge space, While heating the sample and vaporizing it,
A flash point measuring device has been proposed in which a discharge is caused by a discharge electrode to cause ignition in a discharge space, and the temperature at which the ignition occurs is detected. However, with conventional flash point measuring devices of this type, it is difficult to continuously and automatically introduce and discharge the sample into the main body of the device, and it is difficult to effectively stir the sample. It was not functionally sufficient to carry out continuous and automatic process measurements of flash points at factory sites, such as because maintenance was troublesome. The present invention has been made in view of the above circumstances, and provides a flash point measuring device and a measuring method that can efficiently and continuously automatically measure the flash point of a sample, and that reduces the number of times maintenance of discharge electrodes, etc. The purpose is to provide. [Means and effects for solving the problem] In order to achieve the above object, the present invention provides an automatic continuous flash point measuring device for petroleum, etc., which is provided with the following constituent members (A) to (J). (A) The main body of the flash point measuring device (B) A sample introduction and discharge mechanism having a sample introduction tube connected to the lower part of the device main body and an overflow pipe connected to the upper part of the device main body (C) A sample introduction and discharge mechanism connected to the lower part of the device main body. An oxygen-containing gas supply device (D) that has an oxygen-containing gas supply port and supplies oxygen-containing gas from this oxygen-containing gas supply port to the discharge space in the upper part of the device main body; E) A temperature measuring device that measures the temperature of the sample inside the device body (F) A discharge electrode for ignition disposed in the discharge space (G) A discharge power source (H) that is connected to this discharge electrode to generate a discharge a pressure detection device (I) that detects pressure changes in the discharge space; a control unit (J) that controls the sample introduction and discharge mechanism, the oxygen-containing gas supply device, the heating device, the temperature measurement device, the discharge power source, and the pressure detection device, respectively; An exhaust port communicating with the discharge space The present invention also provides a method for introducing a new sample whose flash point is to be measured into the apparatus main body from the sample introduction tube of the sample introduction and discharge mechanism;
The old sample whose flash point has been measured inside the device body is discharged from the overflow tube, and when the sample temperature inside the device body drops to a predetermined temperature due to the introduction of a new sample, the introduction of a new sample is stopped and oxygen is removed. Continuously supply oxygen-containing gas to the discharge space from the oxygen-containing gas supply port of the gas-containing gas supply mechanism through a new sample in the apparatus main body, and exhaust the gas existing in the discharge space out of the system from the exhaust port to the discharge space. Heat the sample inside the device main body at a predetermined temperature increase rate using a heating device while continuously supplying oxygen-containing gas, and after the sample inside the device main body rises to a predetermined temperature below the expected flash point, for a predetermined period of time. The ignition discharge electrode is discharged by giving a signal to the discharge power supply at every interval or every predetermined interval of increase in the sample temperature, and the sample temperature when the pressure detection device detects an increase in the pressure in the discharge space is displayed as the flash point. To provide an automatic continuous measurement method for the flash point of petroleum, etc., which records the flash point and stops heating the sample after detecting the flash point. [Example] Next, an example of the present invention will be described with reference to the drawings, but the present invention is not limited to the following example. In the figure, reference numeral 1 indicates the main body of the flash point measuring device in the form of a closed container made of stainless steel. At the bottom of this device body 1, one end is attached to a sample container 2.
The other end of a sample introduction tube 5, which is immersed in a sample liquid 3 at room temperature whose flash point is to be measured and has an electromagnetic valve 4 interposed therein, is connected. In addition, the device main body 1
One end of the overflow pipe 7 is connected to the drain container 6, and the other end of the overflow pipe 7 is connected to the upper part of the sample introduction pipe 5, and the sample introduction pipe 5 and the overflow pipe 7 constitute a sample introduction and discharge mechanism. When the electromagnetic valve 4 is opened, the sample liquid 3 in the sample container 2 flows into the apparatus main body 1 through the sample introduction tube 5, and the sample liquid 3 existing in the apparatus main body 1 overflows, causing the overflow tube to flow into the apparatus main body 1. The liquid is discharged into the drainage container 6 through the bottom of the device body 1 and the overflow pipe 7.
A sample liquid region 8 is formed between the connecting position and the connecting position. Further, a heating device (electric heater) 9 for heating the sample liquid 3 is provided in the sample liquid region 8 of the apparatus main body 1 . A slider 10 and a power source 11 are connected to the heating device 9, and the amount of heating by the heating device 9 can be increased or decreased by operating the slider 10. In the figure, 12 is a temperature measuring device, and a thermocouple 12a of this temperature measuring device 12 is inserted into the upper part of the sample liquid region 8, so that the temperature of the sample liquid 3 in this liquid region 8 is measured. There is. A discharge space 13 is formed above the sample liquid region 8 in the apparatus main body 1, and a pair of ignition discharge electrodes 14, 14 are arranged in this discharge space 13. One of these electrodes 14, 14 is connected to a discharge power source 16 via a sensing coil 15, and the other is grounded. In addition, these electrodes 14, 14
A plurality of thin wires 14a are protruded from the tip of the other electrode 14 to form a brush shape.
The discharge is performed on these thin wires 14a. In the figure, reference numeral 17 indicates a pressure detection device that is composed of a pressure sensor 18 disposed outside the device main body 1 and a waveguide 19 connected to the pressure sensor 18. The tip of the waveguide 19 is inserted into the discharge space 13 through the side of the device main body 1 and is in communication with the discharge space 13, so that the pressure change occurring in the discharge space 13 is transferred to the waveguide. 19 to the pressure sensor 18. Moreover, 20 in the figure is an air pump. This air pump 20 is connected to one end of an oxygen-containing gas introduction pipe 23 that has an electromagnetic valve 21 and a flow meter 22 interposed therein, and an oxygen-containing gas supply port 24 at the other end of this oxygen-containing gas introduction pipe 23. is connected to the lower part of the device body 1, and these air pump 20, electromagnetic valve 21, flow meter 22, oxygen-containing gas introduction pipe 23, and oxygen-containing gas supply port 24 constitute an oxygen-containing gas supply mechanism. There is. Then, an oxygen-containing body (air) is supplied from the air pump 20 to the lower part of the sample liquid region 8 of the apparatus main body 1, and this oxygen-containing gas passes through the sample liquid 3 in this liquid region 8. After rising while stirring, it is supplied to the discharge space 13. In the figure, 25 indicates a control section including a built-in computer. This control section 25 includes an electromagnetic valve 4, a slider 10, a temperature measuring device 12, a discharge power source 16,
Pressure sensor 18, electromagnetic valve 21, flow meter 22
are in contact with each other to control them. Further, 26 in the figure is a flame arrester. This flame arrester 26 is connected to an exhaust port 27 provided at the upper part of the device main body 1 and communicating with the discharge space 13, so that the discharge space 13 is connected to the exhaust port 27.
and communicates with the atmosphere via an outlet of the flame arrester 26. The apparatus of this embodiment repeatedly performs the following steps under the control of the control section 25, thereby performing continuous automatic measurement of the initial boiling point. A new sample liquid is introduced into the apparatus main body 1 from the sample introduction tube 5, and an old sample liquid from the apparatus main body 1 is discharged from the overflow tube 7. Furthermore, when the sample temperature within the apparatus main body 1 falls below a predetermined temperature due to the introduction of a new sample liquid, the introduction of the new sample liquid is stopped. That is, after the previous measurement is completed (after the discharge occurs in the discharge space 13 and the flash point of the sample liquid 3 is measured), the control unit 25 gives a signal to the electromagnetic valve 4 to open the electromagnetic valve 4, and the apparatus main body 1 A fresh room temperature sample liquid 3 from the sample container 2 is introduced into the chamber. By introducing this new sample liquid 3, the sample liquid 3 that had been in the sample liquid area 8 and whose flash point has been measured is discharged from the overflow pipe 7, and thus the old and new sample liquid 3 can be exchanged in the liquid area 8. happen. In addition, the control unit 25 detects that the temperature of the sample liquid 3 in the liquid area 8 has decreased due to the exchange of the sample liquid 3, and the temperature of this liquid 3 measured by the temperature measuring device 12 has become below a predetermined temperature ( For example, if it is detected that the temperature has fallen below 20℃ below the expected flash point, the electromagnetic valve 4
A signal is given to close the electromagnetic valve 4. Note that the old sample is not discharged during the first measurement. Oxygen-containing gas is continuously supplied from the oxygen-containing gas supply port 24 of the oxygen-containing gas supply mechanism through the sample liquid 3 in the apparatus main body 1 to the discharge space 13 in the upper part of the apparatus main body. That is, the sample liquid 3 in the sample liquid region 8 is continuously passed from the air pump 20 to the discharge space 13.
new oxygen-containing gas is supplied to the discharge space 13.
The vapor of the sample liquid 3, the oxygen-containing gas, and the combustion gas caused by ignition, which were present until then, are discharged from the system through the flame arrester 26 through the exhaust port 27. In this case, the control unit 25 controls the electromagnetic valve 21 according to the amount of oxygen-containing gas detected by the flow meter 22.
The amount of oxygen-containing gas supplied into the device main body 1 is controlled. In this embodiment, an air pump was used as the oxygen-containing gas supply mechanism, but a cylinder may be used instead of the air pump. While continuously supplying oxygen-containing gas to the discharge space 13, the sample liquid 3 in the apparatus main body 1 is heated by the heating device 9 at a predetermined temperature increase rate. At this time, the control unit 25 controls the temperature measuring device 12.
The temperature rise rate is calculated from the temperature value of the sample liquid 3 in the liquid area 8 measured by the , and a signal is sent to the slider 10 according to this temperature rise rate.
This slider 10 is operated to control the amount of thermal energy of the heating device 9. In this case, the amount of thermal energy from the heating device 9 is controlled by controlling the slider 10, and the temperature increase rate is controlled at a predetermined rate (e.g.
heating rate of 0.5°C to 5°C/min, especially 1°C/min)
Adjust to. That is, if the temperature increase rate near the flash point is too rapid, errors will occur in flash point measurement, and the discharge space will become vapor-rich, resulting in a large amount of carbon generation, resulting in frequent maintenance of electrodes and the like. On the other hand, according to the apparatus of this embodiment, the control section 25 calculates the temperature increase rate from the temperature of the sample liquid 3 measured by the temperature measuring device 12, controls the slider 10 based on this, and Since the amount of thermal energy of the heating device 9 is controlled, the rate of temperature rise is controlled, and rapid temperature rise near the flash point is prevented. Further, according to the apparatus of this embodiment, the oxygen-containing gas is first introduced into the lower part of the sample liquid region 8, rises in the sample liquid 3, and then is supplied to the discharge space 13, so that the oxygen-containing gas is Since the sample liquid 3 is effectively stirred when rising in the sample liquid 3, local heating of the liquid 3 is prevented, and the liquid 3
temperature is made uniform, and unevenness in temperature distribution is prevented. The amount of oxygen-containing gas introduced is not particularly limited, but is preferably 50 to 600 ml/min. When the sample liquid 3 in the apparatus main body 1 reaches a predetermined temperature or higher, an electric discharge is generated between the electrodes 14, 14. That is, when the control unit 25 detects that the temperature of the sample liquid 3 in the liquid region 8 has reached a predetermined temperature or higher, it sends a signal to the discharge power source 16 at a predetermined time interval or every predetermined temperature increase interval of the sample until ignition occurs. In this case, the discharge occurs when the sample temperature is a predetermined temperature lower than the expected flash point (for example, about 5
℃) and at predetermined time intervals (e.g. every 0.1 to 20 seconds, especially every 1 second) or every predetermined increase interval of the sample temperature (e.g.
(every 0.1-2℃ increase interval, especially every 0.5℃ increase interval)
cause the discharge to occur. Discharge uses high voltage and constant current discharge, and repeats a certain number of discharges in a short period of time (for example, one cycle is one discharge every 50 to 200 milliseconds, 1 to 25 times). It is preferable to do so, and thereby the wear and tear of the electrodes 14, 14 can be reduced. Further, although the oxygen-containing gas is continuously supplied, it is preferable to stop its introduction during discharge. Note that the pair of discharge electrodes 14, 14 has a tip end portion of the electrode on one side formed into a brush shape by a plurality of thin wires 14a, and discharge is caused by these thin wires 14.
These thin wires 14
a vibrates. Therefore, even if carbon soot or the like generated by ignition adheres to the thin wires 14a, the vibration removes the adhering matter and prevents contamination of the thin wires 14a, so that discharge is always performed well. and electrodes 14, 14
The period for maintenance and inspection can be extended. That is, if such a thin wire 14a is not provided, the spark discharge electrode is likely to be contaminated by adhesion of carbon, etc., and it is difficult to automatically remove the adhering contaminants, so the electrode should be maintained and inspected frequently. The electrodes 14, 14, which have brush-shaped tips, have been improved in this respect, and have a self-cleaning effect. are doing. The sample temperature when the pressure detection device 18 detects an increase in the pressure in the discharge space 13 is displayed and recorded as the flash point. That is, the control unit 25 stores the temperature of the sample liquid 3 when the discharge signal is applied to the discharge power source 16, and when a pressure change in the discharge space 13 caused by ignition is detected by the pressure sensor 18,
Display and record the temperature at this time as the flash point. The automatic continuous flash point measuring device of this embodiment measures the ignition timing in the discharge space 1 caused by ignition.
Since the detection is made at the pressure increase of 3, the ignition timing can be detected accurately, and therefore the flash point can be measured without error. In addition, the pressure detection device 17 is replaced by a pressure sensor 18.
and a waveguide 19, and the pressure sensor 18 is provided outside the device main body 1, so that the pressure sensor 18 is less likely to be contaminated by carbon soot etc. generated during the discharge that occurs in the discharge space 13. This prevents deterioration in the function of the pressure sensor 18 due to this, and also facilitates maintenance and inspection of the pressure sensor 18. Moreover, even if the pressure sensor 18 is provided outside the device main body 1 in this way, the pressure change (pressure increase) due to ignition is evenly transmitted to any location in the discharge space 13, so the waveguide 1
This pressure change is reliably transmitted to the pressure sensor 18 via the pressure sensor 9, and the pressure sensor 18 can always reliably detect the pressure change due to ignition. In addition, the waveguide 19 can be disposed at any location as long as it is disposed in communication with the discharge space 13, since the pressure increase is uniformly transmitted to any part of the discharge space 13 as described above. The location of the pipe 19 does not affect the transmission of pressure changes. After finishing the flash point side, heating of the sample liquid 3 is stopped and the process returns to the above step. That is, after the measurement of the flash point is completed, the heating of the sample liquid 3 by the heating device 9 is stopped, and the flash point of the next sample is then measured by repeating the above steps. The automatic continuous flash point measurement device of this example uses the above-mentioned components and processes to continuously perform sample exchange, gas remaining in the discharge space, sample heating, discharge, flash point detection, etc. Flash point measurements of samples can be carried out continuously and automatically. In addition, it is possible to control the heating rate of the sample to prevent rapid temperature rise near the flash point, allowing for highly accurate measurements, and preventing the discharge space from becoming vapor-rich. It becomes possible to reduce the frequency of maintenance. Furthermore, since the oxygen-containing gas can be raised through the sample and then supplied to the discharge space, it is possible to prevent the sample from being agitated by the oxygen-containing gas and cause uneven temperature distribution, allowing for highly accurate measurements. can be done. In this case, when measuring the flash point using the device of this example, the amount of oxygen-containing gas introduced, the heating rate of the sample, and the intensity, number, and time interval of the electric sparks are factors that affect the measured value. According to the above device, these factors are controlled by the control unit, so the flash point can be measured with sufficient correlation with the petroleum product flash point test method (tag sealed type) specified in JIS K2539. , equipment maintenance is simplified. The device of this embodiment measures the flash point in about 3 to 10 minutes each time, and continuously measures the flash point automatically, making it easy to measure the flash point of petroleum, etc. Therefore, it is very effectively used for processing purposes at sites such as petroleum distillation processes. [Experimental Example] Next, an experimental example will be shown. The flash points of various liquids were measured using the apparatus of the above example, and compared with the values measured by the flash point measuring method specified in JIS. The results are shown in Tables 1 and 2.

【table】

[Table] From the results in Tables 1 and 2, it was found that the flash point measurement results using the apparatus of this example had sufficient correspondence with the JIS method. Therefore, it was confirmed that this device, which is much simpler than the JIS method, is effective for measuring the flash point of petroleum, etc. [Effects of the Invention] As explained above, the automatic continuous flash point measuring device and measuring method of the present invention have the following effects () to (). () By performing the above steps ~, a new sample is introduced into the device body from the sample introduction tube, the old sample in the device body is discharged from the overflow tube, the introduction of a new sample is stopped, and the vapor remaining in the discharge space is removed. , discharging oxygen-containing gas, combustion waste gas, etc., heating the sample with a heating device, discharging the ignition discharge electrode at predetermined time intervals or predetermined sample temperature increase intervals, discharging oxygen-containing gas from an oxygen-containing gas supply device, Stopping the supply, detecting the flash point using the pressure detection device, and introducing the sample for the next measurement can be performed continuously and automatically. Therefore,
Flash point measurements of samples can be carried out continuously and automatically. () By using a heating device that controls the rate of temperature rise of the sample under the control of the control unit, it is possible to control the rate of temperature rise of the sample and prevent rapid temperature rise near the flash point. can. Therefore, it is possible to perform highly accurate measurements, and also to prevent the discharge space from becoming vapor-rich, thereby reducing the number of times electrodes and the like need to be maintained. () The oxygen-containing gas supply port of the oxygen-containing gas supply device is provided at the bottom of the device body.
The oxygen-containing gas can be raised through the sample before being supplied to the discharge space. Therefore, the sample can be effectively stirred by the oxygen-containing gas, and it is possible to prevent the temperature distribution from becoming uneven and perform highly accurate measurements.

[Brief explanation of the drawing]

The drawings are schematic diagrams showing one embodiment of the present invention. 1... Apparatus body, 3... Sample, 5... Sample introduction tube, 7... Overflow tube, 9... Heating device,
12...Temperature measuring device, 13...Discharge space, 14
... Discharge electrode, 16 ... Discharge electrode, 17 ... Pressure detection device, 20 ... Air pump, 24 ... Oxygen-containing gas supply port, 25 ... Control unit, 26 ... Flame arrester, 27 ... Exhaust mouth.

Claims (1)

[Scope of Claims] 1. A flash point measuring device main body, a sample introduction/discharge pipe mechanism having a sample introduction tube connected to the lower part of the device main body, and an overflow pipe connected to the top of the device main body, and a lower part of the device main body. an oxygen-containing gas supply mechanism having an oxygen-containing gas supply port connected to the oxygen-containing gas supply port and supplying the oxygen-containing gas from the oxygen-containing gas supply port to the discharge space in the upper part of the apparatus main body; an apparatus; a temperature measuring device for measuring the temperature of a sample within the apparatus main body; an ignition discharge electrode disposed within the discharge space; a discharge power source connected to the discharge electrode to generate a discharge; and a discharge space. a pressure detection device that detects pressure changes within; a control unit that controls each of the sample introduction and discharge mechanism, the oxygen-containing gas supply mechanism, the heating device, the temperature measurement device, the discharge power source, and the pressure detection device; and a control unit that communicates with the discharge space. 1. An automatic continuous flash point measuring device for petroleum, etc., characterized in that it is equipped with an exhaust port. 2. Introduce a new sample whose flash point is to be measured into the device body from the sample introduction tube of the sample introduction and discharge mechanism, and discharge the old sample whose flash point has been measured inside the device body from the overflow tube, and then insert the new sample into the device body. When the temperature of the sample inside the device body drops to a predetermined temperature due to the introduction of the gas, the introduction of a new sample is stopped, and the new sample is passed from the oxygen-containing gas supply port of the oxygen-containing gas supply mechanism into the discharge space into the discharge space. Gas is continuously supplied, the gas present in the discharge space is discharged from the system through the exhaust port, and while oxygen-containing gas is continuously supplied to the discharge space, the sample inside the device body is heated to a specified temperature using a heating device. After heating the sample in the device body to a predetermined temperature below the expected flash point, a signal is given to the discharge power source at predetermined time intervals or at predetermined intervals of increase in the sample temperature to control the ignition discharge electrode. A method for controlling the ignition of petroleum, etc., characterized by performing a discharge, displaying and recording the temperature of the sample when an increase in pressure in the discharge space is detected by a pressure detection device as the flash point, and stopping heating the sample after the flash point is detected. Point automatic continuous measurement method.