JPS60140150A - Measurement of initial boiling point - Google Patents

Abstract

PURPOSE:To accurately and simply measure an initial boiling point in good reproducibility, by continuously detecting the temp, rising amount of a specimen at every predetermined time after initial droplet is detected and detecting a temp. when the temp. rising amount reaches a predetermined one or less. CONSTITUTION:After a specimen solution 4 is put in a hermetically closed container 1, it is continuously heated at a predetermined heating speed by a heater 13 under the control part 23 and distilled. Specimen vapor is flowed into a cooling tube 10 and condensed therein to enter a dripping pipe 15 and, after a predetermined amount of the condensed specimen is accumulated in a liquid sump pipe 19, initial droplet is dropped from the liquid end part 18 of the liquid sump pipe 19 and detected by a liquid droplet detector 21 while the detection signal is sent to the control part 23. When the control part 23 receives the initial droplet signal, it continuously operates the temp. rising amount of the specimen at every predetermined time on the basis of the distillation temp. of vapor sent from a temp. detector 21 to the control part 23 and a temp., when the temp. rising amount at every predetermined time reaches a predetermined one or less, is displayed as an initial boiling point.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an initial boiling point measuring method capable of measuring the initial boiling point of petroleum products and the like with good 71J accuracy.

Conventionally, in the oil refining industry, petroleum fractions such as crocin and light gas oil are distilled using process distillation equipment, and the initial boiling point, middle distillation temperature, end point, etc. are measured. ．． ing. This 1li1+ constant result is JI
It is adjusted according to the measurement results by the standard test method prescribed in S, and operational management, product management, etc. are performed based on this value.

As a device for measuring the initial boiling point of kerosene, light gas oil, etc. distilled by such process distillation equipment, a droplet detection device was installed at the sample outlet of the cooling pipe of the distillation equipment to detect the cut. However, it is generally difficult to accurately set the initial boiling point of petroleum products, etc. to a process distillation device with good reproducibility. In the case of a device that has been used, the distillate temperature per unit time rises suddenly during the first drop, and the temperature rises rapidly.
There is a problem of poor reproducibility because the dripping temperature varies greatly depending on the internal state of the liquid passage in the measuring device, such as dirt on the inner wall of the cooling tube or detection tube. In this case, it may be possible to use a tester specified by JIS to measure the initial boiling point, but the initial boiling point measurement method using the tester specified by JIS is quite different for each liquid to be tested. Although it is suitable for accurately determining the initial anchoring point in a laboratory, it is difficult to operate, so it is not suitable for use in a factory. is not very suitable.

For this reason, there has been a demand for a method for accurately and reproducibly measuring the initial boiling point of petroleum products and the like easily at a factory site using a process distillation apparatus.

As a result of intensive studies in view of the above circumstances, the inventors of the present invention have determined that the sample liquid in the heating tank is heated at a heating rate by a heating device, and the vapor of the sample generated in the heating tank is heated. One of them is the cooling pipe connected to the tank! The vapor of this sample is introduced from 1h1 and liquefied in the cooling pipe and dripped from the other end of the cooling pipe.The first @ of the sample is detected by a droplet detector installed at the other end of the cooling pipe and the sample at that time is detected. In the method of measuring the initial boiling point of the sample liquid, the temperature is measured by the temperature detector V connected to the heating 4ti. The initial boiling point of petroleum products, etc. can be determined accurately and accurately by using a process distillation device. The inventors have discovered that the method can be readily applied and easily measured, leading to the present invention.

That is, the present inventors found that the distillation curve has a gentle slope near the initial boiling point A, as shown in Figure 1, and that the temperature gradient near the initial boiling point is always constant for the same test liquid. , and focusing on the fact that the temperature gradient is steep at the beginning of distillation, the temperature gradient of the 2-resolution curve is continuously detected near the initial boiling point, and the initial boiling point is determined when the temperature gradient becomes below a predetermined temperature gradient. As a result, it was discovered that if a sample draws a certain distillation curve, a certain initial boiling point is always detected.The present invention can eliminate contamination on the inner walls of cooling tubes, detection tubes, etc. The initial boiling point can be detected without variation depending on the internal state of the liquid passage of the measuring device, and by setting the temperature gradient value for determining the initial boiling point to an appropriate value, the measurement results can be detected using a tester specified by JIS. It is possible to match the measurement results obtained by

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

Figure 2 shows an example of the apparatus used to carry out the method of the present invention. In the figure, 1 is a closed container (heating tank) into which the sample liquid whose initial boiling point is to be measured is introduced. . Into this airtight container 1, one end of a sample introduction tube 7, which has a filter 2° flow rate: ll'3, a solenoid valve 4, a measuring cup 5, and a solenoid valve 6f interposed in sequence, is hermetically inserted from its upper end side. , sample introduction n from the sample introduction port 8 at the other end of the sample introduction tube 7
The sample introduced into 7 passes through the filter 2, the flow rate @13, and the nonolube 4, and is temporarily stored in the divided cutlet 5 (at this time, the pulp 6 is closed), and the sample other than the predetermined amount is transferred to the needle side cup. After the sample is geobar-flowed through the overflow pipe 9 connected to the tube 5, the valve 4 is closed and the valve f6 is opened so that a predetermined amount of the sample enters the closed container 1.

Reference numeral 10 also includes a sample flow tube 11 through which the sample flows and a cooling water flow tube 12 disposed around the sample flow tube 11. A cooling tube in which the sample flowing through the flow tube 11 is cooled.
One end of the sample flow tube 11 of this cooling tube 10 is connected to the upper part of the closed container 1, and the vapor of the sample 14 in the closed container 1 heated by the heater 13 flows into this cooling tube 10, and this cooling After being liquefied in the tube 10, the burette 16 is passed through the dripping pipe 15 connected to the other end of the cooling tube 10.
It is something that goes inside.

Furthermore, in this device, the above-mentioned dripping '? A droplet detection mechanism 17 is interposed on the upper part of the eve 15. As shown in Fig. 3, this droplet detection mechanism 17 has a droplet detection mechanism 17 in which the lower end of a liquid reservoir pipe 19 having a droplet end port 8 formed at the lower end is connected to the upper end of a glass tube 20, and the droplet detection mechanism 17 A droplet detector 21 that detects all the droplets is disposed around this glass tube 20, and is located at the upper end of the liquid reservoir tube 19 and the glass tube 20.
The lower ends thereof are connected to the drip pipe 15, so that they are inserted into the drip pipe 15. Then, the liquefied sample flowing out from the cooling pipe 10 enters the liquid distillation tube 19 and comes out as a liquid from the liquid end 18, and this droplet falls inside the glass tube 20. This falling droplet is then detected by the droplet detector 21.

A temperature sensor 22 is inserted into the sample liquid flow pipe 11 and has one end located above the closed container 1. 23 is a control section with a built-in computer that communicates with the thermal device 13, the droplet detector 21, and the temperature detector 22, and 24 is a control section for this control. Record ill contacting department 23,
25 is control nl! 23 and the temperature detector 21, and the controller 23 controls the heating device 1.
3 is controlled 1 to adjust the heating temperature and heating rate appropriately, and a - signal from the temperature detector 22 is sent to the control unit 23 via the converter 25, and the temperature is recorded as 0. Recorded on number 124-1
-β'1-625 The temperature of the rice is detected by the drop detector 21,
After the signal is sent to the control unit 23, the control unit 23 continuously calculates the amount of increase in sample temperature at predetermined time intervals.

When measuring the initial boiling point of a test liquid using the above device, first put the sample liquid 14 into the closed container 1, and then
is continuously heated by the heater 13 at a predetermined heating rate under the control of the control unit 23 to distill it. Then, the sample vapor flows into the cooling pipe 10, where it is liquefied and enters the drip pipe 15. After a predetermined amount of the liquefied sample is retained in the liquid distillation pipe 19, the liquid in the liquid distillation pipe 19 is When the rice grain temperature drops from the end port 18 and is detected by the droplet detector 21,
The signal is sent to the control section 23. Next, the control section 23
When the first detection signal is received, the control unit 23 continuously calculates the amount of sample temperature increase at each predetermined time based on the distilled steam temperature sent from the temperature detector 21 to the control unit 23, and The temperature when the temperature rise 1 becomes below a predetermined 1 F is displayed as the initial boiling point.

That is, as shown in Part 4, after detecting the first detection point a,
Immediately calculate the amount of sample temperature rise △xI l per Ffr foot time Δ
△x21△x2 rΔx4 Δxn is continuously detected and calculated, and the time point when the sample temperature increase amount △xn becomes less than the predetermined amount ΔXp (the temperature at time 2 when △xn≦ΔXp becomes the initial boiling point A) With this, the initial boiling point A can be measured with good reproducibility.

In addition, in the present invention, the predetermined time Δt is 80 to 4
It is preferable to set it to about 00 milliseconds. In addition, the predetermined amount △ It is possible to match the measurement results, and the trouble of adjusting the measurement results is unnecessary.

As mentioned above, the method for measuring the initial boiling point according to the present invention involves heating the sample liquid in the heating tank at a predetermined heating rate with the heating device, and at the same time, the i8 gas of the sample generated in the heating tank is heated. The rice is introduced into a heating tank [Jf] from one end of the connected cooling pipe, and this trial steam is liquefied in the cooling pipe and dripped from the other end of the cooling pipe. In the method of measuring the initial boiling point of the sample liquid by detecting the sample temperature at that time with a droplet detector connected to the heating tank, after detecting the rice grain temperature, By continuously detecting the amount of sample temperature rise per hour, and setting the temperature when the sample temperature rise per predetermined time becomes less than a predetermined amount as the initial boiling point, oil, petroleum products, etc. It is possible to easily measure the initial boiling point of

[Brief explanation of drawings]

Figure 1 is a graph showing the change in distillation temperature over time when petroleum products are distilled in a distillation apparatus, Figure 2 is a schematic diagram showing an example of the apparatus used to carry out the present invention, and Figure 3 is a graph showing the change in distillation temperature over time when petroleum products are distilled using a distillation apparatus. FIG. 4 is a sectional view showing the droplet detection mechanism, and is an explanatory view for explaining the measuring method of the present invention. Engineering: Airtight container (heating tank, 10~・cooling pipe, 13・
...Giant heater (heating device 9.14...Sample liquid, 17...
・Droplet detection mechanism, 21...Droplet detector, 22...Temperature detector, 23...Control unit 1, Figure 1 Time Figure 4

Claims (1)

[Claims] 1 The sample liquid in the heating tank is heated at a predetermined heating rate by a heating device, and the sample vapor generated in the heating tank is introduced from one end into a cooling pipe connected to the heating tank, and the sample vapor is In the cooling pipe, let it be lower than the other end of the cooling pipe,
The initial boiling point of the sample liquid is measured by detecting the cut portion with several detectors installed at the other end of the cooling tube and detecting the sample temperature at that time with a temperature detector connected to the heating tank. In the method of
The initial boiling point measuring force method is characterized by the fact that the initial boiling point is the temperature when the sample temperature rise per tJJ falls below a predetermined value.