JP2010281554A - Compounding calculating device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compounding calculating device accurately predicting resistivity of mixed combustion ash by considering components of carbonized fuel and coal and their compounding ratio and of calculating a compounding ratio achieving the resistivity of the mixed combustion ash within an optimal range for dust collection by an electric dust collector during mixed combustion of the carbonized fuel obtained by carbonization treatment of sludge and coal by a coal-burning boiler. <P>SOLUTION: The compounding calculating device includes: an ash resistivity prediction means predicting resistivity of mixed combustion ash generated during mixed combustion of the carbonized fuel and coal by considering component analysis values of the carbonized fuel and coal and an ash resistivity decline ratio corresponding to the compounding ratio with respect to a reference ash resistivity set from resistivity of a mono-fuel combustion ash generated during mono-fuel combustion of coal; and a compounding calculating means for calculating a compounding ratio of the carbonized fuel and coal so that the predicted resistivity of the mixed combustion ash is within a management range by the electric dust collector. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a blending calculation device and a program for calculating a blending ratio when carbonized fuel and coal are co-fired with a coal boiler.

  In recent years, environmentally friendly energy has been effectively utilized by reusing waste. There are various types of biomass fuel that reuses waste. For example, there is a carbonized fuel obtained by carbonizing sludge treated with sewage (hereinafter referred to as sewage sludge). Sewage sludge is generated constantly and in large quantities with human activities and is excellent in terms of procurement potential, but the components contained in sewage sludge change day by day and the quality of carbonized fuel also varies slightly.

  Attempts have been made to burn this carbonized fuel in a coal-fired power plant. Therefore, in order to absorb fluctuations in the quality and supply amount of carbonized fuel, the generated carbonized fuel can be effectively used by appropriately managing the supply amount and quality of the carbonized fuel, and the demand amount and required quality of the user. A biomass fuel supply system has been proposed (see Patent Document 1).

  The blending ratio when carbonized fuel and coal are co-fired is determined in consideration of the calorific value of the mixed fuel of carbonized fuel and coal, the environmental impact of exhaust gas (NOx amount, etc.), the amount of ash generated, and the like.

  Here, dust in the exhaust gas containing coal ash (fly ash) generated in a coal-fired power plant is removed using an electric dust collector or a bag filter. An electrostatic precipitator consists of two dust collectors arranged in parallel and a discharge electrode arranged in the center between both dust collectors. A high voltage is applied between the dust collector and the discharge electrode to corona It generates electric discharge and collects dust in the exhaust gas using Coulomb force.

The specific resistance (electrical resistivity) of dust that can keep high dust collection efficiency with an electric dust collector is 10 ⁴ -10 ¹⁰ Ω · cm, but the specific resistance of ash of overseas coal, which has been increasing in recent years, is 10 ¹² -10 ^Since it is as high as ¹³ Ω · cm, it has been pointed out that the reverse ionization phenomenon occurs and the dust collection efficiency decreases (for example, see Patent Document 2). That is, when the specific resistance of the dust is high, charges are accumulated in the dust without corona discharge, and when the electric field formed by this charge reaches the dielectric breakdown limit strength, positive ions are generated from the dust collection electrode toward the discharge electrode. The reverse ionization phenomenon that pops out occurs. As a result, negative ions in the dust collection space are neutralized by positive ions, and dust collection efficiency is reduced.

  Therefore, when using coal with high ash resistivity, the specific resistance of ash (hereinafter referred to as mixed ash) when mixed with a coal boiler is reduced by measures such as mixing with coal with low ash resistivity, Fuel formulation has been designed to optimize dust collection efficiency in electric dust collectors.

Furthermore, even if consideration is given to formulation design, if the specific resistance of the mixed ash is expected to exceed a certain limit (eg, 10 ¹¹ Ω · cm), a pulse charge is applied to suppress the reverse ionization phenomenon. A method for maintaining the dust collection efficiency of the dust collector has been proposed (see Patent Document 3). In the method of Patent Document 3, the specific resistance of the mixed ash is weighted by multiplying the specific resistance of the ash (hereinafter referred to as “combustion ash”) when each coal is burned alone by the respective blending ratio. Averaged values are used.

JP 2005-106390 A Japanese Patent Laid-Open No. 1-171662 JP-A-8-229433

  However, when carbonized fuel carbonized from sewage sludge is burned in a coal boiler, the specific resistance of the co-fired ash changes when co-firing carbonized fuel, which has a different component from coal. It is unclear how it will affect the dust collection efficiency.

  Therefore, similarly to the method of Patent Document 3, even if the specific resistance of the mixed ash is predicted by a simple weighted average, there is a problem that the reliability of the predicted value is poor. As a result, there is a problem that the influence on the dust collection efficiency in the electric dust collector cannot be predicted in advance, and the blending ratio of carbonized fuel and coal cannot be determined.

  Therefore, the object of the present invention is to accurately determine the specific resistance of the co-fired ash in consideration of the carbonized fuel and the components of the coal and the blending ratio thereof when the carbonized fuel obtained by carbonizing the sewage sludge and the coal are co-fired in the coal boiler. It is an object of the present invention to provide a blending calculation apparatus and program capable of predicting and calculating the blending ratio of carbonized fuel and coal so that the specific resistance of the mixed ash is within the optimum range for dust collection by an electric dust collector.

  In order to solve the above-mentioned problems, the inventors have conducted intensive investigations. As a result, when a mixed fuel in which a small amount of carbonized fuel is mixed with coal is burned in a coal boiler, the ratio of the mixed ash is higher than that of the coal-only ash. It has been found that the resistance decreases to about half and the dust collection efficiency of the electric dust collector is improved. Furthermore, it has been found that the specific resistance of the mixed ash can be predicted with a certain accuracy in consideration of the components of carbonized fuel and coal and the blending ratio thereof, and the present invention has been completed.

  That is, the blending calculation apparatus according to the present invention is a blending calculation apparatus that calculates a blending ratio when carbonized fuel obtained by carbonizing sewage sludge and coal in a coal boiler, and component analysis of the carbonized fuel and coal Corresponding to the component ash analysis value and blending ratio of the carbonized fuel and coal to the standard ash specific resistance set from the input device that inputs data including values and the specific resistance of the special ash generated when the coal is fired exclusively In consideration of the ash specific resistance reduction rate, the ash specific resistance predicting means for predicting the specific resistance of the mixed ash generated when the carbonized fuel and coal are co-fired, and the predicted specific resistance of the mixed ash, A blending calculation means for calculating the blending ratio of carbonized fuel and coal so as to be within the control range of the electric dust collector, and an output device for outputting data including the calculation result of the blending ratio of carbonized fuel and coal by the blending calculation means And with It is characterized in.

  In addition, the reference ash specific resistance may be set from a value obtained by weighted averaging the specific resistance of the exclusive combustion ash generated when the carbonized fuel and coal are exclusively burned.

  In addition, the ash specific resistance reduction rate may be set and updated based on the relationship between the reference ash specific resistance and the apparent specific resistance of the co-fired ash generated when the carbonized fuel and coal are co-fired. .

  Further, the data input by the input device includes a boiler specification related to a combustion method of the coal boiler and a dust collector specification related to a management range of ash specific resistance in the electric dust collector, and the ash specific resistance reduction rate is: In addition to the component analysis values of the carbonized fuel and coal and the blending ratio thereof, it is set so as to correspond to the boiler specifications, and the blending calculation means is based on the management range of the ash specific resistance corresponding to the dust collector specifications. A percentage may be calculated.

  Further, the program according to the present invention is a blending calculation program for calculating a blending ratio when carbonized fuel obtained by carbonizing sewage sludge and coal in a coal boiler, and is produced only when the coal is exclusively fired. When the carbonized fuel and coal are co-fired, taking into account the ash specific resistance reduction rate corresponding to the component analysis value of the carbonized fuel and coal and the blending ratio thereof, to the reference ash specific resistance set from the specific resistance of ash A process for predicting the specific resistance of the mixed ash generated in the gas and a process for calculating the blending ratio of carbonized fuel and coal so that the predicted specific resistance of the mixed ash is within the control range of the electric dust collector It is made to carry out.

  According to the present invention, when carbonized fuel carbonized from sewage sludge and coal are co-fired in a coal boiler, the specific resistance of the co-fired ash can be accurately predicted in consideration of the components of carbonized fuel and coal and their blending ratio. It is possible to calculate the blending ratio of carbonized fuel and coal so that the specific resistance of the mixed ash is within the optimum range for dust collection by the electric dust collector. As a result, the generated carbonized fuel can be effectively utilized at the optimum location.

1 is a schematic diagram of a coal boiler system according to a first embodiment of the present invention. It is a block diagram showing the structure of the compounding calculation apparatus concerning the 1st Embodiment of this invention. It is a line graph showing the relationship between the specific resistance ratio of the mixed combustion ash concerning the 1st Embodiment of this invention, and the mixture ratio of carbonized fuel. It is a flowchart showing the mixing | blending calculation method concerning the 1st Embodiment of this invention. It is a schematic diagram of the coal boiler system concerning the 2nd Embodiment of this invention. It is a flowchart showing the compounding calculation method concerning the 2nd Embodiment of this invention. It is a schematic diagram of the coal boiler system concerning the 3rd Embodiment of this invention. It is a flowchart showing the compounding calculation method concerning the 3rd Embodiment of this invention.

  EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated in detail, referring an accompanying drawing below. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified.

[First Embodiment]
FIG. 1 is a schematic diagram of a coal boiler system according to a first embodiment of the present invention. This coal boiler system is a system for co-firing carbonized fuel obtained by carbonizing sewage sludge and coal.

  The flow of fuel and exhaust gas treatment in the coal boiler system will be described with reference to FIG. The coal stored in the coal bunker 1 and the carbonized fuel stored in the carbonized fuel yard 2 are respectively sent to the coal feeder 3, and the mixed fuel is blended in the coal feeder 3 so as to have a predetermined blending ratio. Here, the blending ratio of the carbonized fuel and coal is calculated in advance by the blending calculation device 5 and input to the coal feeder 3. The mixed fuel is pulverized by the pulverized coal machine 4 and then supplied to the coal boiler 6 together with the combustion air heated by the air preheater 7 at the subsequent stage of the coal boiler.

  Exhaust gas generated when the mixed fuel is burned in the coal boiler 6 is passed through the flue gas denitration device (not shown) and the air preheater 7 to the electric dust collector 8 where most of the dust is removed. Is done. After confirming the dust concentration with the dust concentration meter 9, the remaining dust is removed by the bag filter 10. Further, desulfurization in the exhaust gas is performed by a flue gas desulfurization apparatus (not shown), the dust concentration is finally confirmed again by the dust concentration meter 9, and the cleaned exhaust gas is discharged from the chimney 11.

  As shown in FIG. 1, not only coal and carbonized fuel are mixed by the coal feeder 3, but also carbonized fuel may be sent directly from the carbonized fuel yard 2 to the coal bunker 1 and mixed in the coal bunker 1. . FIG. 2 is a block diagram showing the configuration of the blending calculation apparatus according to the present embodiment. When the blending calculation device 5 co-combusts the carbonized fuel and the coal in the coal boiler, the input device 21 for inputting the data including the component analysis values of the carbonized fuel and the coal, the storage device 23 for storing the input data and the operation program. Is composed of an arithmetic unit 22 for calculating the blending ratio and an output device 24 for outputting the blending result. Hereinafter, each configuration will be described in detail.

  The input device 21 is used to input component analysis values of carbonized fuel and coal. The input component analysis value needs to cover the data used in the subsequent formulation calculation. Specifically, at least the following data is required.

Calorific value, total moisture Industrial analysis data (intrinsic moisture, ash, volatiles, fixed carbon content)
Elemental analysis data (carbon, hydrogen, oxygen, nitrogen, sulfur, chlorine, phosphorus content, etc.)
Ash composition analysis (silica, alumina, phosphorous pentoxide, etc.)
Normally, coal is regularly supplied in a fixed amount by sea transportation, and its component analysis value is measured at the time of receiving the coal yard. In the case of coal from the same production area, the components are almost stable and it is sufficient to measure at the time of acceptance.

  In the case of carbonized fuel, it is regularly supplied in small quantities from a sewage treatment plant. Of the component analysis values, the calorific value is the basic data for calculating the blending ratio, so it is measured at a high frequency (for example, one week / time), and other component analysis values are regularly (for example, several months / time). Is measured. Although the components of carbonized fuel vary slightly, it is known that the variation range of carbonized fuel from the same sewage treatment plant is within a certain range, and there is no problem if there is data measured periodically. In addition, when a seasonal variation is recognized in the component contained in sewage sludge, you may refer the component analysis value measured in the past same period.

In the arithmetic device 22, the arithmetic program memorize | stored in the memory | storage device 23 is performed with the processor (not shown) in the arithmetic device 22, and the calculation related to a compounding calculation is performed. The calculation is performed using the following means. That is,
1) In consideration of the ash specific resistance reduction rate corresponding to the component analysis value of carbonized fuel and coal and the blending ratio to the reference ash specific resistance set from the specific resistance of the special ash generated when coal is burned exclusively, Ash resistivity prediction means 25 for predicting the resistivity of the mixed ash generated when carbonized fuel and coal are mixed,
2) The blending calculation means 26 calculates the blending ratio of the carbonized fuel and coal so that the specific resistance of the mixed ash is within the control range of the electric dust collector 8.

  The ash specific resistance predicting means 25 first obtains a reference ash specific resistance. The reference ash specific resistance is an ash specific resistance that is a reference for predicting the specific resistance of the mixed fired ash, and is set from the specific resistance of the coal fired ash in this embodiment. The specific resistance of the coal-burned ash can be calculated not only by predicting from its ash component, but also by referring to past combustion results in coal of the same component (same production area).

  Next, the specific resistance of the mixed ash of carbonized fuel and coal is predicted in consideration of the ash specific resistance reduction rate in the standard ash specific resistance. Even if it is a small amount, when carbonized fuel is blended with coal, the specific resistance of the mixed ash is significantly lower than the specific resistance of the coal-burned ash. In order to reflect this phenomenon, an ash resistivity reduction rate was provided.

  A phenomenon in which the specific resistance of the mixed ash is lower than the specific resistance of the coal-fired ash will be described with reference to FIG. FIG. 3 is a line graph showing the relationship between the specific resistance ratio of the mixed ash of carbonized fuel and coal and the blending ratio of the carbonized fuel. Here, the specific resistance ratio of the mixed ash was calculated as a ratio between the specific resistance of the mixed ash and the specific resistance of the coal-burned ash (ash when the blending ratio of carbonized fuel was zero). Although there are two data in the figure, this is because there are two exhaust gas lines, A line and B line, passing through the electrostatic precipitator 8. Moreover, the specific resistance of ash was calculated as an apparent specific resistance by a method described later from an applied voltage and a measured current in an electric dust collector. The blending ratio of the carbonized fuel was calculated as a weight ratio of the carbonized fuel to coal.

  As shown in FIG. 3, the specific resistance ratio of the mixed ash decreases linearly as the blending ratio of the carbonized fuel increases. In particular, when the blending ratio of the carbonized fuel is 3.9% by weight, the specific resistance ratio is close to 0.5, and it can be seen that the specific resistance of the mixed ash is reduced to about half of the specific resistance of the coal-fired ash.

The ash components were analyzed to investigate the factors that significantly reduce the specific resistance of co-fired ash by blending carbonized fuel. Table 1 shows the compositional analysis results of the coal and carbonized fuel combustion ash.

Table 1 shows that phosphorous pentoxide (P ₂ O ₅ ) is hardly contained in coal-burning ash, whereas carbonization fuel-burning ash contains 20% or more regardless of the date of manufacture. I understand. As described above, the composition ratio of phosphorus pentoxide (P ₂ O ₅ ) is greatly different between coal and carbonized fuel-burning ash.

The mechanism by which the specific resistance of the entire mixed ash is greatly reduced due to the high ash composition ratio of phosphorus pentoxide (P ₂ O ₅ ) is estimated as follows. Phosphorus pentoxide (P ₂ O ₅ ) is highly reactive with water and becomes phosphoric acid (orthophosphoric acid, H ₃ PO ₄ ) when reacted with moisture in the exhaust gas. Since phosphoric acid has a melting point of about 50 ° C., it becomes liquid in the exhaust gas in the electrostatic precipitator (usually at 100 ° C. or higher), but this liquid phosphoric acid exhibits high electrical conductivity, that is, has a specific resistance. It is known that it is small, and it is thought that the specific resistance of the mixed ash as a whole has also decreased significantly due to this effect.

Therefore, in predicting the specific resistance of the special combustion ash, it is necessary to consider not only the blending ratio of the carbonized fuel but also the ash composition analysis value. By combining these, a function F _d (P _c , P _b , x) representing the ash specific resistance reduction rate is defined. As parameters to be considered, P _c is a composition analysis value of coal-burning ash, P _b is a composition analysis value of carbonized fuel ash, and x is a blending ratio of carbonization fuel. Here, assuming that the specific resistance of the mixed ash is ρ _m , ρ _m can be obtained from equation (1).

(Equation 1)
ρ _m = ρ _c · F _d (P _c , P _b , x) ------- (1)
Here, an optimal function may be used for the function F _d (P _c , P _b , x) to represent the ash specific resistance reduction rate.

For example, in FIG. 3, since only the blending ratio is changed using the same coal and carbonized fuel, the variable is only the blending ratio x, and this function is F _d (x). Furthermore, as shown in FIG. 3, it can be seen that F _d (x) can be expressed by a linear function. When the rate of change of the specific resistance ratio of the mixed ash with respect to the blending ratio is −k (k> 0), the expression (1) can be replaced with the expression (2).

(Equation 2)
ρ _m = ρ _c (1-x · k) ------- (2)
In the above description, the standard ash specific resistance is set from the specific resistance of coal-fired ash, but it is also set from the value obtained by weighted averaging the specific resistance of each of the special ash of coal and carbonized fuel according to the blending ratio. May be. This is because when the blending ratio of the carbonized fuel is large (for example, 10% or more), the specific resistance of the mixed ash can be predicted more rationally by considering the specific resistance of the combustion ash of the carbonized fuel itself.

When setting the reference ash specific resistance from the weighted average value, if the specific resistance of the carbonized fuel-burned ash is ρ _b , the equation (1) can be replaced with the equation (3).

(Equation 3)
ρ _m = {(1-x) ρ _c + x · ρ _b } F _d (P _c , P _b , x) ------- (3)
Next, the blending calculation means 26 will be described. First, a blend that satisfies general conditions such as the calorific value of the fuel mixture of carbonized fuel and coal, the environmental impact of the exhaust gas (NOx amount, etc.), the amount of ash generated, etc. is calculated to determine the temporary blend. About this temporary mixture, it is confirmed whether the predicted specific resistance of the mixed ash is within the control range (for example, 10 ⁴ to 10 ¹⁰ Ω · cm) in the electrostatic precipitator 8.

  If it is predicted that the specific resistance of the mixed ash will be outside the above control range, it can be mixed with coal with a low ash specific resistance within the range that satisfies the above-mentioned general conditions, or an additional blend of carbonized fuel and within the control range. Adjust the formulation so that As mentioned above, as the blending ratio of carbonized fuel increases, the specific resistance of mixed ash tends to decrease, so it is an effective measure to blend a larger amount of carbonized fuel when burning coal with high ash specific resistance. is there.

  Examples of the blending calculation apparatus 5 described above include personal computers, workstations, main frames, and the like. Examples of the input device 21 include a mouse, a keyboard, and a receiving unit that receives data transmitted wirelessly or by wire. Examples of the storage device 23 include a hard disk drive, a volatile or nonvolatile memory, a CD-ROM, a CD-RAM, a DVD-ROM, and a DVD-RAM. Examples of the output device 24 include a display, a printer, and a hard disk drive.

  Next, the flowchart showing the blending calculation method according to this embodiment shown in FIG. 4 will be described. First, component analysis values necessary for blending calculation are input for carbonized fuel and coal (S1). The specific resistance of the coal-burning ash is calculated from the input component analysis value and the like, and set as the reference ash specific resistance (S2). Next, the blending ratio of carbonized fuel and coal is assumed so as to satisfy the general conditions described above (S3). The ash specific resistance reduction rate corresponding to the blending ratio and component analysis value is calculated, and the specific resistance of the mixed ash is predicted by multiplying the reference ash specific resistance by the ash specific resistance reduction rate (S4). It is confirmed whether or not the specific resistance of the mixed ash is within the control range of the electrostatic precipitator 8 (S5), and if it is out of the control range, the mixture ratio is assumed again (S3). If it is in a management range, a mixture ratio will be fixed and a result will be transmitted to coal feeder 3 (S6).

  According to the first embodiment, when carbonized fuel obtained by carbonizing sewage sludge and coal are co-fired in the coal boiler 6, the ratio of the co-fired ash in consideration of the component analysis values of carbonized fuel and coal and the blending ratio thereof. The resistance can be accurately predicted, and the blending ratio of carbonized fuel and coal can be calculated such that the specific resistance of the mixed ash is within the optimum range for dust collection by the electric dust collector 8.

[Second Embodiment]
FIG. 5 is a schematic diagram of a coal boiler system according to the second embodiment of the present invention. In the present embodiment, in contrast to the first embodiment shown in FIG. 1, the blending calculation device 5 is also connected to the electric dust collector 8 so that data can be transmitted.

  In the present embodiment, the ash specific resistance reduction rate used in the ash specific resistance predicting means 25 shown in FIG. 2 is the reference ash specific resistance and the apparent ratio in the electric dust collector of the mixed ash generated when the carbonized fuel and coal are mixed. Set and update based on the relationship with the resistor.

Here, the apparent specific resistance ρ _m ′ of the mixed ash is V applied voltage at the electric dust collector, I is the measurement current, A is the area of the dust collecting electrode, and L is the distance between the dust collecting electrode and the discharge electrode. ).

(Equation 4)
ρ _m '= V / I × A / L ------- (4)
Substituting ρ _m ′ in equation (4) into ρ _m in equation (1) and organizing the ash specific resistance reduction rate F _d (P _c , P _b , x) yields equation (5). The calculation method of the ash specific resistance reduction rate is set and updated so as to satisfy this relationship.

(Equation 5)
F _d (P _c , P _b , x) = ρ _m ′ / ρ _c ------- (5)
FIG. 6 is a flowchart showing the blending calculation method according to the present embodiment. Compared to the first embodiment shown in FIG. 4, the blending ratio is determined and the result is transmitted to the coal feeder (S6) and thereafter. Processing (S11 to S15) is added.

The added process will be described. A mixed fuel obtained by mixing carbonized fuel and coal based on the formulation determined in process S6 is co-fired in a coal boiler (S11). At that time, the applied voltage and current in the electrostatic precipitator 8 are measured (S12), and the apparent specific resistance of the mixed ash is calculated from the above-described equation (4) (S13). It is confirmed whether the apparent specific resistance of the mixed ash is within the allowable miscalculation range of the predicted specific resistance value of the mixed ash predicted in S4 (S14). When the apparent specific resistance of the mixed ash is outside the allowable error range, the calculation method of the ash specific resistance reduction rate is updated (S15), and the update result is reflected in the calculation of the ash specific resistance reduction rate from the next time (S4). . Specifically, the various coefficients of the function F _d (P _c , P _b , x) representing the ash specific resistance decrease rate are updated based on the latest data so as to satisfy the expression (5). If the apparent resistivity of the mixed ash is within the allowable error range, the process is terminated.

  According to the second embodiment, in addition to the effects of the first embodiment, when data on the apparent specific resistance of the mixed ash increases due to the accumulation of combustion performance of carbonized fuel, the data can be flexibly reflected. In addition, the accuracy of the prediction of the specific resistance of the mixed ash can always be kept high.

  In the above description, the composition calculation device 5 is connected to the electrostatic precipitator 8. However, as shown in FIG. 5, the composition calculation device 5 is also connected to the bag filter 10 and the dust densitometer. You may enable it to transmit. This is because the dust collection efficiency of the electric dust collector can be directly confirmed from the measured values of the differential pressure gauge of the bag filter and the dust concentration meter.

[Third Embodiment]
FIG. 7 is a schematic diagram of a coal boiler system according to the third embodiment of the present invention. In the present embodiment, in contrast to the first embodiment shown in FIG. 1, the blending calculation device 5 is connected to the coal feeders 3 of a plurality of coal boiler systems so that data can be transmitted. This blending calculation device 5 is characterized in that the blending ratio can be calculated in consideration of the specifications of the target coal boiler system.

  In the present embodiment, the data input by the input device 21 of the blending calculation device 5 shown in FIG. 2 includes boiler specifications related to the combustion method of the coal boiler 6 in addition to the component analysis values described in the first embodiment. And the dust collector specification concerning the management range of the ash specific resistance in the electric dust collector 8 is included. Further, the ash specific resistance reduction rate used in the ash specific resistance predicting means 25 is set so as to correspond to this boiler specification in addition to the component analysis values of carbonized fuel and coal and the blending ratio thereof. The blending ratio of carbonized fuel and coal is calculated based on the control range of ash specific resistance corresponding to this dust collector specification.

  Since the ash components and ash specific resistance generated slightly vary depending on the combustion method and combustion temperature of the coal boiler 6, the prediction accuracy can be further improved by predicting the specific resistance of the mixed ash in consideration of the boiler specifications. it can. In addition, since the range of ash specific resistance suitable for dust collection varies depending on the manufacturer and model of the electrostatic precipitator 8, by using a management range corresponding to the dust collector specifications, a reasonable blending ratio that appropriately reflects the equipment specifications can be obtained. Can be calculated.

  FIG. 8 is a flowchart showing the blending calculation method according to this embodiment. In contrast to the first embodiment shown in FIG. 4, processing S21 and processing S22 are added before the processing S1, and determination S23 is added after the determination S5.

  In the present embodiment, first, a coal boiler system is selected from a plurality of options and temporarily determined (S21), and boiler specifications and dust collector specifications in the coal boiler system are input (S22). Thereafter, component analysis values necessary for blending calculation are input for the carbonized fuel and coal (S1), and the specific resistance of the coal-burned ash is calculated from the input component analysis values and set as the reference ash specific resistance (S2). ). Furthermore, the blending ratio of carbonized fuel and coal is assumed so as to satisfy the general conditions described above (S3). The ash specific resistance reduction rate corresponding to the blending ratio, component analysis value, and boiler specifications is calculated, and the specific resistance of the mixed ash is predicted by multiplying the reference ash specific resistance by the ash specific resistance reduction rate (S4).

  Next, it is confirmed whether or not the specific resistance of the mixed ash is within the management range corresponding to the dust collector specification (S5). If it is outside the control range, it is confirmed whether or not the coal boiler system needs to be further changed (cannot be handled by changing the blending ratio) (S23). If it is necessary to change the coal boiler system, the process returns to the assumption of the coal boiler system (S21) again. If it is not necessary to change, the process returns to the assumption of the blending ratio (S3). If the specific resistance of the mixed ash is within the control range of the electric dust collector 8, the blending ratio is determined and the result is transmitted to the coal feeder 3 (S6).

  According to the blending calculation method shown in FIG. 8, an optimum coal boiler system for co-firing carbonized fuel can be selected from a plurality of options, and the generated carbonized fuel can be effectively used at the optimum location.

DESCRIPTION OF SYMBOLS 1 Coal bunker 2 Carbonization fuel place 3 Coal feeder 4 Pulverized coal machine 5 Compounding calculation device 6 Coal boiler 7 Air preheater 8 Electric dust collector 9 Dust concentration meter 10 Bag filter 11 Chimney 21 Input device 22 Arithmetic device 23 Storage device 24 Output device 25 Ash resistivity prediction means 26 Formulation calculation means

Claims (5)

A blending calculation device that calculates a blending ratio when carbonized fuel carbonized with sewage sludge and coal in a coal boiler,
An input device for inputting data including component analysis values of the carbonized fuel and coal;
In consideration of the ash specific resistance reduction rate corresponding to the component analysis value of the carbonized fuel and coal and the blending ratio thereof, to the reference ash specific resistance set from the specific resistance of the dedicated ash generated when the coal is exclusively burned, Ash specific resistance prediction means for predicting the specific resistance of the mixed ash generated when the carbonized fuel and coal are mixed,
A blending calculation means for calculating a blending ratio of carbonized fuel and coal so that the predicted specific resistance of the mixed ash is within a control range in the electric dust collector;
A blending calculation apparatus comprising: an output device that outputs data including a calculation result of a blending ratio of carbonized fuel and coal in the blending calculation means.   The reference ash specific resistance is set from a value obtained by weighted averaging the specific resistance of the exclusive combustion ash generated when the carbonized fuel and coal are exclusively burned, according to the blending ratio. Formulation calculation device.   The ash specific resistance reduction rate is set and updated based on a relationship between the reference ash specific resistance and an apparent specific resistance of the mixed dust ash generated when the carbonized fuel and coal are co-fired. The compounding calculation apparatus according to claim 1 or 2. Data input by the input device includes a boiler specification related to a combustion method of the coal boiler and a dust collector specification related to a management range of ash specific resistance in the electric dust collector,
The ash specific resistance reduction rate is set to correspond to the boiler specifications in addition to the component analysis value of the carbonized fuel and coal and the blending ratio thereof,
The said compounding calculation means calculates the said compounding ratio based on the management range of the ash specific resistance corresponding to the said dust collector specification, The compounding calculation apparatus of Claim 1 to 3 characterized by the above-mentioned. A blending calculation program for calculating a blending ratio when carbonized fuel obtained by carbonizing sewage sludge and coal in a coal boiler,
In consideration of the ash specific resistance reduction rate corresponding to the component analysis value of the carbonized fuel and coal and the blending ratio thereof, to the reference ash specific resistance set from the specific resistance of the dedicated ash generated when the coal is exclusively burned, A process for predicting the specific resistance of the mixed ash generated when the carbonized fuel and coal are mixed,
A blending calculation program for causing a computer to perform a process of calculating a blending ratio of carbonized fuel and coal so that the predicted specific resistance of the mixed ash is within a management range in an electric dust collector.

Images