WO2018034514A1 - Method for measuring and analyzing amount of unburned carbon in coal ash by using frequency phase angle - Google Patents

Abstract

The present invention relates to a method for measuring the amount of unburned carbon in coal ash, comprising the steps of: transmitting a signal having a predetermined frequency to coal ash; receiving a signal having passed through the coal ash; measuring the phase angle of the received signal; and calculating the amount of unburned carbon, which is contained in the coal ash, by using the measured phase angle, such that in the measurement and analysis of the amount of unburned carbon in coal ash, analysis can be performed quickly by using a frequency phase angle.

Description

Determination and Analysis of Fly Ash Unburned Carbon Content Using Frequency Phase Angle

The present invention relates to a method for measuring coal ash unburned carbon content using a frequency phase angle, and to transmit and receive a signal having a predetermined frequency to coal ash, and to measure coal ash unburned carbon content using a phase angle of a received signal. It is about.

Among the industrial wastes that are generated a lot in Korea, coal ash is the ash generated after burning the coal briquettes in coal-fired power plants. It is divided into fly ash and fly ash. Coal ash generated from coal-fired power plants has been sent to ash ponds in the past, and most of them are landfilled. However, nowadays, it is effective to increase the strength of concrete by mixing the appropriate amount during cement production. It is becoming a trend.

Coal ash used in coal-fired power plants needs continuous automatic measurement of unburned carbon content due to optimizing boiler combustion to increase power plant output efficiency, high-quality coal ash recycling, and harmful gases. Many studies have been conducted to determine the effective amount of unburned carbon, and there is increasing social interest in the field of new energy.

Prior arts related to the present invention include 'multipath removal apparatus for unburned carbon powder measuring device (Korean Patent Publication No. 10-206-0038526)'.

The first problem to be solved by the present invention is to provide a method for measuring the coal ash unburned carbon content using the frequency phase angle.

The second problem to be solved by the present invention is to provide an apparatus for measuring coal ash unburned carbon content using a frequency phase angle.

The present invention to solve the first problem, the step of transmitting a signal having a predetermined frequency to the coal ash; Receiving a signal passing through the coal ash; Measuring a phase angle of the received signal; And it provides a coal ash unburned carbon content measuring method comprising the step of calculating the coal ash unburned carbon content contained in the coal ash using the measured phase angle.

According to another embodiment of the present invention, the coal ash unburned carbon content may be a coal ash unburned carbon content measuring method, which is inversely proportional to the phase angle.

According to another embodiment of the present invention, the coal ash unburned carbon content may be a coal ash unburned carbon content measuring method characterized in that it is inversely proportional to the tangent value of the phase angle, the frequency of the signal, and the resistance value of the measurement circuit.

According to another embodiment of the present invention, the resistance value may be a coal ash unburned carbon content measuring method, characterized in that it is set to a predetermined value calculated from the maximum unburned carbon content to be measured and the phase angle at that time. .

According to another embodiment of the present invention, it may be a coal ash unburned carbon content measuring method further comprising the step of outputting or transmitting the calculated coal ash unburned carbon content to the outside.

In order to solve the second problem, the present invention transmits a signal having a predetermined frequency to coal ash, and a signal transmission and reception unit for receiving the signal passing through the coal ash; And measuring a phase angle of the received signal, and calculating a coal ash unburned carbon content included in the coal ash using the measured phase angle.

According to another exemplary embodiment of the present invention, the coal ash unburned carbon content may be a coal ash unburned carbon content measuring device, which is inversely proportional to the phase angle.

According to another embodiment of the present invention, the coal ash unburned carbon content is inversely proportional to the tangent value of the phase angle, the frequency of the signal, and the resistance value of the measurement circuit, and the resistance value is the maximum unburned carbon content to be measured. And it may be a coal ash unburned carbon content measuring device, characterized in that it is set to a predetermined value calculated from the phase angle at that time.

According to another exemplary embodiment of the present invention, the coal ash unburned carbon content measuring apparatus may further include a display unit configured to output the calculated coal ash unburned carbon content.

According to the present invention, in the measurement and analysis of coal ash unburned carbon content, it is possible to analyze in a short time by using the frequency phase angle. In addition, there is an advantage that easy installation.

1 is a block diagram of a coal ash unburned carbon content measuring apparatus according to an embodiment of the present invention.

Figure 2 shows an industrial site to which coal ash unburned carbon content measuring apparatus according to an embodiment of the present invention is applied.

Figure 3 shows the principle of the unburned carbon content of the coal ash unburned carbon content measuring apparatus according to an embodiment of the present invention.

4 to 7 show a comparison between the predicted value and the actual measured value of the coal ash unburned carbon content measuring apparatus according to an embodiment of the present invention.

8 is a flowchart illustrating a method for measuring coal ash unburned carbon content according to an embodiment of the present invention.

9 is a flowchart illustrating a method for measuring coal ash unburned carbon content according to another embodiment of the present invention.

Coal ash unburned carbon content measuring method according to an embodiment of the present invention comprises the steps of transmitting a signal having a predetermined frequency to the coal ash, receiving the signal passing through the coal ash, measuring the phase angle of the received signal And calculating the coal ash unburned carbon content included in the coal ash using the measured phase angle.

Prior to the description of the specific contents of the present invention, for the convenience of understanding, the outline of the solution of the problem to be solved by the present invention or the core of the technical idea will be presented first.

Coal ash unburned carbon content measuring method according to an embodiment of the present invention comprises the steps of transmitting a signal having a predetermined frequency to the coal ash, receiving the signal passing through the coal ash, measuring the phase angle of the received signal And calculating the coal ash unburned carbon content included in the coal ash using the measured phase angle.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, these examples are intended to illustrate the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited thereby.

The configuration of the invention for clarifying the solution to the problem to be solved by the present invention will be described in detail with reference to the accompanying drawings, based on the preferred embodiment of the present invention, the components of the other drawings when necessary for the description of the drawings Note that you can quote. In addition, in the following detailed description of the operating principle of the preferred embodiment of the present invention, when it is determined that the detailed description of known functions or configurations related to the present invention and other matters may unnecessarily obscure the gist of the present invention, The detailed description is omitted.

1 is a block diagram of a coal ash unburned carbon content measuring apparatus according to an embodiment of the present invention.

Coal ash unburned carbon content measuring apparatus 100 according to an embodiment of the present invention is composed of a signal transmission and reception unit 110 and a processing unit 120. It may further include a communication unit (not shown).

The signal transmission and reception unit 110 transmits a signal having a predetermined frequency to the coal ash, and receives a signal passing through the coal ash.

More specifically, in order to use the frequency and the phase angle to detect the unburned carbon content contained in the coal ash, a signal having a frequency as a reference is transmitted to the coal ash. The signal transmitted to the coal ash passes through the coal ash and receives the signal which passed. The phase angle of the received signal is used to detect coal ash unburned carbon content. As shown in FIG. 2, coal ash is generated in an industrial site, such as a thermal power plant, and a signal is transmitted to and received from coal ash in order to detect unburned carbon content contained in the coal ash.

The processor 120 measures the phase angle of the received signal, and calculates the coal ash unburned carbon content included in the coal ash using the measured phase angle.

More specifically, the signal transmitted by the signal transmission / reception unit 110 passes through coal ash to calculate the phase angle of the received signal. The phase angle of the signal may be a conventional phase angle measuring method or a measuring device such as an oscilloscope. The unburned carbon content of coal ash is calculated from the calculated phase angle.

The coal ash unburned carbon content is inversely proportional to the phase angle. The relationship of coal ash unburned carbon content is inversely proportional to the phase angle, and the coal ash unburned carbon content can be measured using the phase angle. The unburned carbon content is proportional to the capacitance value of the signal, which is inversely proportional to the tangent of the phase angle, the frequency of the signal, and the resistance value of the measurement circuit.

This can be derived from the following equations (1) to (3) the relationship between the phase angle and the unburned carbon content.

f is the frequency, c is the capacitance value can be seen as the content of unburned carbon.

As shown in FIG. 3A, the phase angle θ may be calculated from X _c and R.

Here, R is a resistance value of the measurement circuit, and the resistance value is set to a predetermined value calculated from the maximum unburned carbon content to be measured and the phase angle at that time.

For efficient measurement, the relationship according to FIG. 3 (b) is used. 3 (b) is a graph of y = tan ⁻¹ (x). However, since the slope is not linear, it is efficient to use the domain section with the largest change rate. This can be derived from the derivative as follows.

This is the same as Figure 3 (c), it can be seen that the most efficient when x = 0. Using this, the resistance value is calculated using the maximum unburned carbon content and the phase angle at which the value corresponding to x is minimum, and the R value is set as the resistance value.

For example, when the frequency is 2.437 Ghz, substituting Equation 2 is as follows.

The frequency f and the resistance R are known values, indicating the relationship between the phase angle θ and the unburned carbon content c.

Based on the results obtained through the above equations and experiments, the relationship between the phase angle and the unburned carbon content can be derived. The relationship between the phase angle and the unburned carbon content is stored in a table, and the unburned carbon content may be derived through the phase angle with reference to the table. Predicting the phase angle and unburned carbon content using the above relationship, it can be seen that the linear inverse relationship is shown in Table 1 and FIG. 5.

%	pF	Y	θ
0.00	25	1.57	57.58
2.31	37	1.06	46.77
3.51	41	0.96	43.83
4.45	46	0.86	40.55
5.27	50	0.79	38.21
7.13	59	0.67	33.71
8.16	62	0.63	32.41
10.30	72	0.55	28.67
11.20	78	0.50	26.78

Hereinafter, the results obtained using the relationship between the phase angle and the unburned carbon content are compared with the actual results.

For the actual measurement, as shown in Figure 5, an experimental apparatus was installed. The transmitter generates 2.412 Ghz, which is input to the receiver frequency phase comparator via coal ash coal. The frequency phase comparator is then applied to the ADC at the DC level. Thus, the ADC device samples continuously. The frequency difference between the reference frequency and the coal ash coal briquettes is expressed as DC 0 to 6 volts. DC level is continuously sampled and delivered to the MCU using 16-bit parallel communication. The results are shown in Table 2 and FIG. 6.

%	Volt DC	θ1 (reference frequency)	θ2 (change frequency)	Result θ out (θ1--θ2)
0.00	1.39	123	45	78
2.31	1.35	123	52	71
3.51	1.24	123	60	63
4.45	1.13	123	68	55
5.27	1.08	123	75	48
7.13	0.87	123	92	31
8.16	0.86	123	100	23
10.30	0.76	123	108	15
11.20	0.68	123	118	5

Comparing the two results is shown in FIG. It can be seen that the higher the coal ash coal briquettes, the smaller the phase angle is. The different slopes are caused by the influence of temperature and humidity, and the error can be corrected by considering the data.

The apparatus may further include a display unit for outputting the calculated coal ash unburned carbon content or a communication unit for transmitting to the outside.

8 is a flowchart of a method for measuring coal ash unburned carbon content according to an embodiment of the present invention, Figure 9 is a flowchart of a method for measuring coal ash unburned carbon content according to another embodiment of the present invention. Detailed description of each step corresponds to the detailed description of FIGS. 1 to 7, and thus redundant descriptions thereof will be omitted.

Step 810 is a step of transmitting a signal having a predetermined frequency to the coal ash, step 820 is a step of receiving a signal passed through the coal ash. The signal having a preset frequency is transmitted to the coal ash, and the signal which passed the coal ash is received.

In operation 830, a phase angle of the received signal is measured.

Step 840 is a step of calculating the coal ash unburned carbon content included in the coal ash using the measured phase angle. The coal ash unburned carbon content may be linearly inversely proportional to the phase angle, and more specifically, may be inversely proportional to the tangent value of the phase angle, the frequency of the signal, and the resistance value of the measurement circuit. The resistance value may be set to a predetermined value calculated from the maximum unburned carbon content to be measured and the phase angle at that time.

Step 910 is outputting or transmitting the coal ash unburned carbon content to the outside.

Embodiments of the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on the media may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

In the present invention as described above has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations are possible from these descriptions.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and all the things that are equivalent to or equivalent to the claims as well as the following claims will belong to the scope of the present invention. .

The present invention relates to a coal ash unburned carbon content measuring method comprising the steps of transmitting a signal having a predetermined frequency to the coal ash, receiving the signal passing through the coal ash, measuring the phase angle of the received signal, and the By calculating the coal ash fine carbon content contained in the coal ash using the measured phase angle, the coal ash fine carbon content can be measured and analyzed using the frequency phase angle.

Claims (9)

1. Transmitting a signal having a predetermined frequency to coal ash;

   Receiving a signal passing through the coal ash;

   Measuring a phase angle of the received signal; And

   The coal ash unburned carbon content measuring method comprising the step of calculating the coal ash unburned carbon content contained in the coal ash using the measured phase angle.
2. The method of claim 1,

   The coal ash unburned carbon content,

   Coal ash unburned carbon content measuring method characterized in that inversely proportional to the phase angle.
3. The method of claim 1,

   The coal ash unburned carbon content,

   Coal ash unburned carbon content measuring method characterized in that inversely proportional to the tangent of the phase angle, the frequency of the signal, and the resistance value of the measuring circuit.
4. The method of claim 3, wherein

   The resistance value is,

   Coal ash unburned carbon content measuring method characterized in that it is set to a predetermined value calculated from the maximum unburned carbon content to be measured and the phase angle at that time.
5. The method of claim 1,

   Coal ash unburned carbon content measuring method further comprising the step of outputting or outputting the coal ash unburned carbon content to the outside.
6. A signal transmitting and receiving unit for transmitting a signal having a predetermined frequency to the coal ash and receiving the signal passing through the coal ash; And

   Coal ash unburned carbon content measuring apparatus comprising a processing unit for measuring the phase angle of the received signal, and calculates the coal ash unburned carbon content contained in the coal ash using the measured phase angle.
7. The method of claim 6,

   The coal ash unburned carbon content,

   Coal ash unburned carbon content measuring device, characterized in that inversely proportional to the phase angle.
8. The method of claim 6,

   The coal ash unburned carbon content,

   Inversely proportional to the tangent of the phase angle, the frequency of the signal, and the resistance of the measurement circuit,

   The resistance value is,

   Coal ash unburned carbon content measuring device, characterized in that it is set to a predetermined value calculated from the maximum unburned carbon content to be measured and the phase angle at that time.
9. The method of claim 6,

   Coal ash unburned carbon content measuring device further comprises a display unit for outputting the calculated coal ash unburned carbon content.

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