JP2012251998A - Measurement device for solvent insoluble matter of coal tar or coal tar pitch type - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measurement device of a solvent insoluble matter of coal tar or coal tar pitch type a having a measurement area for measuring QI measurement with high accuracy in a wide range for measuring a solvent insoluble matter of coal tar or coal tar pitch type a by a simple method without requiring any complicate operation or instrument.SOLUTION: A measurement device mixes a coal tar pitch type a and a solvent b, and supplies its mixed solvent a" to an integrating sphere type turbidimeter 20 (flow cell 16) to measure its turbidity, and calculates a solvent insoluble matter QI of the pitch type a on the basis of the measured turbidity. In this case, the solvent a" is gradually stirred and diluted in first and second stirring tanks 13 and 15 so that diluting accuracy can be increased, and that solvent quantity can be reduced. The integrating sphere type turbidimeter 20 is not influenced by color or diameter of particles configuring the turbidity, and is made excellent in the measurement of turbidity of a material including many insoluble matters having various colors or different particle diameters such as aromatic components, alkyl side chains, heterocycle compounds, sulfur, nitrogen, and oxygen, like the pitch type a. Thus, it is possible to obtain accurate QI across QI=0.1 to 30% on the basis of the measured turbidity.

Description

  The present invention relates to a measuring apparatus for insoluble components of coal tar or coal tar pitches.

Solvent insoluble matter contained in coal tar and coal tar pitches that are coal tar derivatives (including soft pitch, medium pitch, hard pitch, pitch in various work processes), such as polycyclic aromatic organic compounds, Coke powder, coal, etc. are used to produce coke such as needle coke and pitch coke from coal tar and coal tar pitches (hereinafter collectively referred to as “coal tar pitches”). It is considered to be important to influence the properties of the coke obtained at that time, for example, the coefficient of thermal expansion (CTE), the hard glove grindability index (HGI) and the like.
In measuring the solvent-insoluble content, it is usually calculated by taking a sample of coal tar pitches, weighing it, and dissolving it in a solvent such as quinoline and then quantifying the insoluble content. In this case, it is displayed as “QI (Quinoline Insoluble)”, and various methods for measuring the QI have been proposed.

For example, a liquid fine particle counter (particle counter) is applied to QI measurement of soft pitch, the number of insoluble particles in the sample is measured for each particle diameter, and the characteristic value is obtained from the correlation between these and the QI value. A measuring apparatus that automatically calculates QI from the characteristic value using an arithmetic unit has been proposed (Patent Document 1).
In addition, an absorptiometer is applied to measure the QI value of the soft pitch, and further, a high-viscosity bituminous sample sample to be measured is mixed with tar distillate oil as the first solvent to lower the viscosity. Proposed a measuring device that measures the absorbance of a sample after mixing with a mixing device (static mixer), mixing with quinoline as a second solvent, dissolving / diluting a predetermined amount with a static mixer (Patent Document 2). In this apparatus, the time required for QI measurement can be shortened to 20 minutes (paragraph 0037 of the same document).

Japanese Patent Laid-Open No. 04-9664 Japanese Patent Laid-Open No. 08-101100

The technique of Patent Document 1 is limited to the number of particles that can be measured in terms of counting the number of particles, and is therefore only applied to those having a solvent insoluble content of 1% by weight or less. There is a problem that high accuracy cannot be ensured when the measurement area becomes high and the number of particles increases.
Moreover, the technique of patent document 2 is the clogging in the static mixer by the solid content in the bitumen at the time of mixing with a static mixer, for example, the tar distillation in the pump which sends the tar distillate oil which is the 1st solvent. There is a problem of clogging in the pump due to solid content in the oil output, and it is difficult to measure stably. Furthermore, in an absorptiometer, there is a range in the concentration of an object that can be measured. Depending on the QI range to be measured, the dilution factor, that is, the amount of sample (sampling amount) can be changed, or the amount of diluted solvent can be changed. There is also the problem of having to do.

  In view of the above situation, the present invention can perform insoluble content measurement such as QI of coal tar pitches over a wide range of the quantity distribution, has a high accuracy measurement area, and does not require complicated operations and equipment. It is an object to be able to measure the insoluble matter by a simple method.

As a result of intensive studies to solve the above problems, the present inventor found that there is a correlation between the solvent insoluble content of a solution in which coal tar pitches are dissolved in a solvent and the turbidity of the solution, and the insoluble content such as a wide QI value. On the other hand, when the insoluble content is calculated from the turbidity, it is found that the amount of the sample does not vary with respect to the insoluble content to be calculated, and the present invention has been completed. It was.
That is, the present invention is based on means for obtaining a solution in which coal tar pitches and a solvent are mixed, means for supplying the solution to an integrating sphere turbidimeter and measuring the turbidity, and the measured turbidity. A configuration having means for calculating the solvent-insoluble concentration of the coal tar pitch is employed.

  In the present invention, as described above, the turbidity is measured with an integrating sphere turbidimeter, and based on the measurement, the insoluble content of coal tar pitches is obtained. The insoluble matter can be accurately measured regardless of the amount without changing or changing the amount of diluted solvent. For this reason, the present invention has a measurement region that can be measured with high accuracy over a wide range of QI = 0.1 to 30%, and is a solvent for coal tar pitches by a simple method without requiring complicated operations and equipment. Insoluble matter can be measured.

1 is a schematic configuration diagram of a QI analyzer according to an embodiment of the present invention. Configuration diagram of the turbidimeter of the same embodiment Relationship diagram between turbidity and QI in the same embodiment

  Hereinafter, the present invention will be described in more detail with reference to the embodiments. However, the present invention is not limited to these embodiments as long as the gist thereof is not exceeded.

  The integrating sphere turbidimeter in the present invention is not affected by the color and diameter of the particles constituting the turbidity, and, like coal tar pitches, aromatic components, alkyl side chains, heterocyclic compounds, sulfur, nitrogen, It is excellent for measuring turbidity, although it contains a lot of insolubles of various colors such as oxygen and different particle sizes.

The coal tar in the present invention is preferably coal tar which is obtained by cooling the crude steel coke oven gas produced in the coke oven in a stepwise manner and condensing and separating one having a high boiling point. The coal tar thus obtained contains a large amount of aromatic components, alkyl side chains and heterocyclic compounds, sulfur, nitrogen and oxygen. The coal tar pitches of the present invention are preferably those obtained by removing light aromatic components by distillation of the above coal tars.
Furthermore, examples of the solvent of the present invention include quinoline, toluene, pyridine, acetone, hexane, alcohol and the like, and quinoline is preferable from the viewpoint of high solubility in coal tar pitches.

A method of mixing these solvents and coal tar pitches is not particularly limited, but it is preferable to use a stirring tank because coal tar pitches have high viscosity. In this stirring tank, blockage does not occur in the mixer as compared with the method of mixing in the process line by a static mixer.
At this time, if a part of the solution obtained in the agitation tank is extracted, and the extracted solution is further diluted and supplied to the integrating sphere turbidimeter, a highly viscous coal tar pitch can be obtained. Therefore, the amount of solvent used can be reduced.

  Various means such as liquid feeding by a metering pump can be considered as a means for obtaining a certain amount of coal tar pitch. For example, a branch pipe of a sample line taken out from the process line or the process line has a sampling mechanism. Connected to the agitation tank, and the solvent feeding pipe is connected to another port of the sampling mechanism. It is possible to feed a certain amount of coal tar pitch into the stirring tank by filling the coal tar pitch into the stirring tank and then feeding the solvent through the inside into the stirring tank. This action can automatically wash the metering line with a solvent, is useful for the automation of the entire system, and is effective in automatically calculating the solvent insoluble content concentration.

  Hereinafter, the outline of the measurement apparatus, the measurement method, and the measurement operation will be described in detail with reference to FIGS. 1 and 2 which are an embodiment of the measurement apparatus of the present invention. FIG. 1 is a configuration diagram of the QI analyzer, and FIG. 2 is an enlarged view of the measurement unit.

  In FIG. 1, a branch pipe 11 is branched via an opening / closing valve V1 from an infusion (process) line of coal tar pitch a in coke production or a sample line taken out from the line, and this branch pipe 11 is connected via an opening / closing valve V2. And connected to the sampling mechanism 12. The sampling mechanism 12 is connected to a first stirring tank 13, which is connected to a second stirring tank 15 via a dispensing mechanism 14, and further, the second stirring tank 15 is a pump. It is connected to the flow cell 16 via P5.

  On the other hand, a temporary storage tank D2 is connected to a storage tank D1 of quinoline b serving as a solvent through a pump P1, and one tank D2 passes through a sampling mechanism 12 through a pump P3 to the first stirring tank 13. The other branched and connected is connected to the first stirring tank 13 via the dispensing mechanism 14. In addition, a temporary storage tank D3 is connected to the quinoline b storage tank D1 via a pump P2, and this tank D3 is connected to a dispensing mechanism 14 via a pump P4, and then connected to the second stirring tank 15. It is connected. A waste liquid pump P6 is connected to the dispensing mechanism 14, and the solution in the first stirring tank 13 can be discharged.

  The sampling mechanism 12 may appropriately adopt a conventionally known configuration using a three-way valve or a four-way valve. For example, the sampling mechanism 12 includes two three-way valves connected by a pipe having a required length (capacity). The branch pipe 11 is connected to one port of the three-way valve, the first stirring tank 13 is connected to the other port, and the pump P3 is connected to one port of the other three-way valve. As a configuration of the waste liquid port, the pipe a is filled (sampled) with the pitch a by switching the ports of the three-way valves, and then the solvent b is mixed with the sample pitch a through the inside of the first stirring tank. By feeding to 13, the fixed amount of pitch a used as a sample can be periodically fed to the first stirring tank 13.

  Similarly, the dispensing mechanism 14 can also adopt a conventionally known configuration using a three-way valve or a four-way valve as appropriate. For example, the dispensing mechanism 14 is configured by a metering pump including a syringe pump. Between the second stirring tanks 13 and 15, a fixed amount of sample is fed from the first stirring tank 13 to the second stirring tank 15 by this metering pump, or two three-way valves similar to the sampling mechanism 12 described above. It is possible to adopt a configuration in which a certain amount of sample is fed by the piping structure.

  The branch pipe 11 is maintained at the same temperature as the process line by the steam trace in order to prevent the coal tar pitch from being blocked and the density difference due to the temperature difference. Yes.

  The tank D2 is kept at 75 ° C., which is the temperature at the time of pitch melting specified in JIS-K2425, and the tank D3 is kept at 50 ° C. so as to be higher than the outdoor temperature in summer. The first stirring tank (dilution tank) 13 is kept at 75 ° C., which is the temperature at the time of pitch melting specified in JIS-K2425, and the pitch a is completely dissolved with the solvent b by the stirring blade 13a driven by the motor M1. Let The second stirring tank (dilution tank) 15 dilutes the solution dispensed by the dispensing mechanism 14 with the solvent b with the stirring blade 15a driven by the motor M2.

The flow cell 16 constitutes a part of the turbidimeter 20, and as shown in FIG. 2, when the light c emitted from the laser light source 21 passes through the flow cell 16, The light scattered by the particles becomes scattered light c2 collected in one place by the integrating sphere 22 and is received by the light receiving elements 23 ₁ and 23 ₂ , respectively. Intensity is measured. Based on the intensity ratio between the transmitted light c1 and the scattered light c2, the computing unit 24 determines the turbidity (turbidity / transmitted light intensity / scattered light intensity).

  This analyzer is configured as described above, and all devices such as valves and pumps are automatically controlled. Next, the measurement operation will be described. The solvent b is stored in the tank D2 from the tank D1 through the pump P1. And kept at 75 ° C., which is the temperature at which the coal tar pitch a is dissolved in the stirring tank 13. A fixed amount of solvent (quinoline) b is sent from the bottom to the first stirring tank 13 from the tank D2 through the dispensing mechanism 14 via the pump P3. At this time, the solvent b is prevented from entering the sampling mechanism 12 by switching the three-way valve. If a certain amount is sent, the pump P3 is stopped and V1 is opened, so that the high temperature pitch a passes through the flow rate adjusting valve V2 and further passes through the sampling mechanism 12 to be in a state of being drained.

In this state, the sampling mechanism 12 is filled with the pitch a, the valve V1 is closed, the flow path of the sampling mechanism 12 is switched, and a constant amount of pitch a is stored in the sampling mechanism 12. Become.
Subsequently, when the pump P3 is activated, the solvent b passes from the tank D2 through the sampling mechanism 12 via the pump P3, and a certain amount of the solvent b is generated by the pitch a in the sampling mechanism 12 and the rotation amount of the pump P3. It is fed into the tank 13. At this time, the solvent b is prevented from entering the dispensing mechanism 14 by switching the three-way valve or the like. The ratio of the solvent b to the pitch a is about 125 times.

  In the 1st stirring tank 13 into which the pitch a and the solvent b were sent, stirring is performed with sufficient time and stirring power in order to dissolve the pitch a completely with the solvent b. At this time, the stirring bowl 13 is kept at the above 75 ° C. to keep the solvent b at a constant temperature. When this stirring is completed, the liquid is passed through the dispensing mechanism 14 with the pump P6. In this state, the flow path of the dispensing mechanism 14 is switched, and similarly to the sampling mechanism 12, a mixed sample a ′ of a certain amount of pitch a and solvent b is stored in the dispensing mechanism 14.

  Subsequently, when the pump P4 is started, the solvent b passes from the tank D3 through the dispensing mechanism 14 via the pump P4, and the sample a ′ in the dispensing mechanism 14 and a certain amount of the solvent b depending on the rotation amount of the pump P4 are changed. 2 is fed into the second stirring tank 15. At this time, the ratio of the solvent b to the sample a ′ is set to, for example, 20 times in order to make the measurement range (dilution degree) of the turbidimeter 20 together with the dilution in the stirring tank 13. The total dilution ratio of the solvent b with respect to the sample a 'in both the stirring tanks 13 and 15 is most preferably about 2000 to 3000 times.

  After stirring in the second stirring tank 15, the solution a ″ is sent to the flow cell 16 by the pump P 5, and the turbidity measurement of the solution a ″ is performed with the turbidimeter 20. The arithmetic unit 24 converts the turbidity into QI.

  By this analyzer, QI estimated values from the absorbance analysis by the two-wavelength method according to Patent Document 2: 4.5%, 10.0%, and 23.2% coal tar pitches a are dissolved in the solvent b, and turbidity is obtained. And the pitch concentration in the sample a ″ was changed to obtain the relationship between the pitch concentration and turbidity. In the measured value, for example, when the pitch concentration (g / L) is 0.4 (2500 times dilution), the relationship between the turbidity and the QI at which the square of the correlation coefficient shown in FIG. It was. From FIG. 3, if the turbidity measured by the turbidimeter 20 and the QI of the pitch sample a ″ are close to a straight line, for example, turbidity: y, QI: x, y≈12.401x. It is observed that there is -7.8415. Therefore, by measuring this turbidity, QI of pitches a can be obtained without changing the amount of sample (sampling amount) or changing the amount of diluted solvent as in the technique of Patent Document 2. Can do. Turbidity was output as a value converted to a standard sample of kaolin.

  The measurement operation by the turbidimeter 20 is repeated by alternately feeding and discharging the solution a ″ to the flow cell 16 in order to increase the measurement accuracy as necessary. To do. The cleaning action is as follows. First, the solution in the first stirring tank 13 is discarded by the pump P6 via the dispensing mechanism 14, and the solution in the second stirring tank 15 is discarded by the pump P5 via the flow cell 16. The valve V3 is opened, and the cleaning liquid made of steam or quinoline is drained through the valve V2 and the sampling mechanism 12, whereby the pipe line is cleaned.

  Next, the sampling mechanism 12 is switched, and the solvent b equal to or larger than the above-mentioned fixed amount used at the time of measurement is put into the first stirring tank 13 from the tank D2 through the pump P3 through the sampling mechanism 12. Then, the cleaning solvent b is filled above the liquid level reached by the pitch a, and the liquid level is cleaned. Further, in order to increase the dissolving power (detergency), stirring is performed in the stirring tank 13 kept at 75 ° C. After this stirring, the solution in the stirring tank 13 is drained by the pump P6.

  After washing the first agitation tank 13, the flow path of the dispensing mechanism 14 is switched, and the same amount as that used for the measurement in the second agitation tank 15 from the tank D3 through the dispensing mechanism 14 via the pump P4. After the above solvent b is put, stirring is performed in the stirring tank 15. Thereafter, the solvent b is passed from the stirring tank 15 into the flow cell 16 via the pump P5 and discarded.

  The above QI measurement and cleaning actions are performed, for example, every 20 minutes to 1 hour in coke production, and the production process is controlled based on the real-time QI measurement values.

In the above-described embodiment, the solvent b is fed into the second stirring tank 15 through the pipes of the pumps P2, P4 and the tank D3. However, the sampling mechanism 12 and the dispensing mechanism 14 are provided at the subsequent stage of the pump P3. A three-way valve is provided in the pipe line before branching, and the solvent b can be selectively fed into the branching section or the second stirring tank 15 with the three-way valve.
Further, nitrogen gas can be fed into the stirring tanks 13 and 15 from the upper part thereof, and the solvent b and the like therein can be surely discharged into the lower waste line.

V1, V2, V3 Open / close valves P1, P2, P3, P4, P5, P6 Pumps D1, D2, D3 Tank 11 Branch pipe 12 Sampling mechanism 13 First stirring tank 14 Dispensing mechanism 15 Second stirring tank 16 Flow cell 20 Turbidimeter 21 Turbidimeter light source 22 Turbidimeter integrating sphere 24 Turbidimeter calculator

Claims (4)

  Means for obtaining a solution (a ″) obtained by mixing coal tar or coal tar pitches (a) and a solvent (b), and supplying the solution (a ″) to an integrating sphere turbidimeter An apparatus for measuring the solvent insoluble content of coal tar or coal tar pitch, comprising means for measuring the degree, and means for calculating the solvent insoluble concentration of the coal tar or coal tar pitch (a) based on the measured turbidity.   The apparatus for measuring the solvent insoluble content of coal tar or coal tar pitch according to claim 1, wherein the means for obtaining the mixed solution (a '') is a stirring tank.   A part of the solution (a ′) obtained in the agitation tank is extracted, and the extracted solution (a ′) is further fed into the agitation tank and diluted with stirring, and the diluted solution (a ″) is added to the integrating sphere type. It supplies to a turbidimeter, The measuring apparatus of the solvent insoluble content of coal tar or coal tar pitch of Claim 2 characterized by the above-mentioned.   Means for obtaining a certain amount of the coal tar or coal tar pitch (a) in the means for obtaining the solution (a '') in which the coal tar or coal tar pitch (a) and the solvent (b) are mixed, The process line or a branch pipe of the sample line taken out from the process line is connected to the stirring tank via a sampling mechanism, and the solvent feeding pipe is connected to another port of the sampling mechanism, and the sampling 4. The apparatus for measuring a solvent-insoluble content of coal tar or coal tar pitch according to claim 2, wherein the internal volume of the mechanism is set to the predetermined amount.

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