JP2004183921A - Ash melting apparatus and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ash melting apparatus capable of stably operating an ash melting furnace by automatically controlling variations in fuel properties and ash properties and a method of controlling the apparatus. <P>SOLUTION: This ash melting apparatus comprises a means 221 for accepting the input of information on fuel properties and ash properties, a first calculation means 222 calculating the supplied amount of a substance supplied to an ash melting furnace 100, a second calculation means 223 predicting and calculating an index value showing the operating state of the ash melting furnace based on the supplied amount, a measuring means 224 measuring the operating state of the ash melting furnace, and a comparison means 225 comparing the index value calculated by the second calculation means with the measured results measured by the measuring means. Based on the results of the comparison, the comparison means makes the first calculation means calculate again. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a process for melting coal ash discharged from a coal-fired power plant, and more particularly to a method for controlling an ash melting furnace.
[0002]
[Prior art]
Coal has abundant reserves around the world and is therefore more economical than other fossil fuels. For this reason, the expansion of coal-fired power plants is expected to meet the growing demand for electricity.
[0003]
Such coal contains 10-20% ash in the coal itself, so burning the coal emits unburned coal ash. For example, about 5.7 million tons / year of coal ash are emitted from Japan's coal-fired power plants alone. Of this, about 4.4 million tons / year of coal ash is reused for cement materials and the like, and about 1.3 million tons / year of coal ash that is not reused is landfilled. (For example, see Non-Patent Document 1.)
The discharged coal ash is designated as a managed industrial waste because it elutes heavy metals. For this reason, the disposal cost when landfilling coal ash is on the order of several thousand to 10,000 yen per ton, and tends to increase year by year. In addition, it is difficult to secure land for disposal sites, and there are various problems related to landfill disposal such as an increase in environmental load.
[0004]
Therefore, as a means for sealing heavy metals in coal ash and reducing the volume of coal ash, a method of melting coal ash and collecting it as slag has been proposed. There is also a need for a proposal for a method of reusing the collected slag.
[0005]
For example, in the steel industry, blast furnace slag is reused for concrete aggregate, stone, fiber material (rock wool), and the like (for example, see Non-Patent Document 2). On the other hand, there is also a research example in which coal ash is melted to produce a stone material or a fiber material (for example, see Non-Patent Document 3).
[0006]
However, coal ash has a higher melting point than blast furnace slag and waste incineration ash, and it is necessary to lower the melting point to melt coal ash into slag. There is a research example on a method of reducing the melting point of coal ash (for example, see Non-Patent Document 4).
[Non-patent document 1]
“CCT Journal” issued by the Coal Utilization Center, July 2002, p. 8-15
[Non-patent document 2]
Toshikazu Sakuraya, "Steel Slag Recycling Technology Contributing to a Recycling-Oriented Society", Kawasaki Steel Engineering Reports, April 2000, Vol. 32, NO. 4, p. 43-50
[Non-Patent Document 3]
Watanabe Yasushi, "Development of melting technology for coal-ash and other thermal power station wastes," Nuclear Power Plant, February 1995, Vol. 46, NO. 2, p. 170-175
[Non-patent document 4]
H. J. Hurst, "Energy &Fuels", October 1996, p. 1215-1219
[0007]
[Problems to be solved by the invention]
In order to supply power using coal-fired power generation in the future, it is required to establish a technology for recovering coal ash, which is currently landfilled, as valuable resources. Therefore, a method is considered in which coal ash discharged from a coal-fired power plant is melted and recovered as product slag. As this method, it is conceivable to install an ash melting furnace in a coal-fired power plant, continuously melt the coal ash discharged from the coal-fired power plant, and collect it as product slag. It is also conceivable to use fossil fuels used in coal-fired power plants as fuel for the ash melting furnace.
[0008]
As described above, in order to recover valuable slag as a product, it is necessary to manufacture slag in accordance with market demand and increase added value. For that purpose, in the ash melting furnace, stable combustion in the furnace and its maintenance and management are essential.
[0009]
However, Japanese coal-fired power plants use coal with a high ash melting point, and the brand of coal changes frequently. By using coal having a high ash melting point, the furnace temperature of the ash melting furnace must be maintained higher than the ash melting point. Further, when the brand of coal used changes, the properties of the fuel also fluctuate, and the properties and melting point of the coal ash also fluctuate, so that there is a problem that stable operation of the ash melting furnace is difficult.
[0010]
Therefore, an object of the present invention is to provide an ash melting apparatus for stably operating an ash melting furnace and a control method thereof, in consideration of melting of high melting point ash, and variation in brand of coal used. .
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides, for example, an ash melting furnace for melting ash and manufacturing slag by melting an ash, a slag collecting apparatus for collecting slag, and an ash melting furnace. A first input receiving unit that receives an input of information indicating fuel properties; a second input receiving unit that receives an input of information indicating ash properties; First calculating means for calculating the supply amount of the substance to be supplied to the ash melting furnace using the information indicating the property and the information indicating the ash property, and will be generated based on the supply amount. Second calculating means for predicting and calculating one or more index values indicating the operating state of the ash melting furnace, measuring means for measuring the operating state of the ash melting furnace, and 1 calculated by the second calculating means. More than kind of index value and above measurement Comparing means for comparing the measurement result obtained by the step with the measurement result. The comparing means supplies the first calculating means with the ash melting furnace to a target operating state based on the result of the comparison. Provided is an ash melting apparatus characterized in that recalculation for obtaining an amount is performed.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings.
In the first embodiment, an ash melting device and a control method thereof will be described.
[0013]
FIG. 1 is a diagram showing a control method of the ash melting device.
[0014]
First, the outline of FIG. 1 will be described. The ash melting device includes an ash melting furnace 100 for melting ash, an ash melting furnace control device 200 for controlling the ash melting furnace, various regulators, various sensors for monitoring the operation state, and a slag collecting device 330 for collecting slag.
[0015]
The ash melting furnace 100 will be described with reference to FIG. For the ash melting furnace control device 200, the functions described in FIG. 1 will be described later, and the hardware configuration will be described in FIG.
[0016]
The various adjusters are devices for supplying the supply amounts of the respective substances calculated by the supply amount calculation means 222, which is one of the functions of the ash processing control device, to the ash melting furnace 100. Specifically, there are an air regulator 121, a primary air regulator 122, a secondary air regulator 123, a fuel carrier air regulator 124, an ash carrier air regulator 125, an oxygen regulator 126, and the like.
[0017]
The various sensors are devices for monitoring the operation state of the ash melting furnace 100. The operating state measuring means 224 measures the operating state of the ash melting furnace 100 based on the information output by these sensors. The sensors include a slag flow monitoring device 127, a temperature measuring device 128, an exhaust gas analyzer 129, and the like. The slag flow-down monitoring device 127 is a device that outputs information such as the slag flow-down amount 186 and the slag image data 185 to the operating state measuring means 224. This information is necessary for confirming the stable flow of the slag. The temperature measuring device 128 is a device that outputs the in-furnace temperature 187 to the operating state measuring means 224. The exhaust gas analyzer 129 is a device that outputs the exhaust gas composition 188 and the exhaust gas temperature 189 of the exhaust gas 157 discharged from the ash melting furnace 100 to the operating state measuring means 224.
[0018]
In addition, these sensors may not only output the measured data of the operating state to the operating state measuring unit 224, but also output data estimated from the actual measured data to the operating state measuring unit 224 in some cases.
[0019]
The slag collecting device 330 is a device for collecting the molten slag. The slag recovery device is selected according to the specifications of the slag to be recovered.
[0020]
Next, the configuration of the ash melting furnace 100 shown in FIG. 1 will be described with reference to FIG.
[0021]
The ash melting furnace 100 is a cylindrical furnace having an outlet 101 for exhaust gas 157 at an upper portion and an outlet 102 for slag at a lower portion.
[0022]
The ash melting furnace 100 has at least five types of nozzles: a primary air nozzle 103, a secondary air nozzle 104, a fuel nozzle 105, an oxygen nozzle 106, and an ash nozzle 107. These nozzles are all mounted tangentially to the ash melting furnace 100.
[0023]
Most of the combustion air is divided into primary air 152 and secondary air 153, and is injected into the furnace 130 from the primary air nozzle 103 and the secondary air nozzle. At this time, as a result of the primary air and the secondary air being ejected in a tangential direction, a swirling flow 151 is generated in the furnace 130.
[0024]
The remaining combustion air other than the primary air and the secondary air is used to carry fuel 161 and ash 162. The fuel carrier air 154 is ejected from the fuel nozzle 105, while the ash carrier air 155 is ejected from the ash nozzle 107 into the furnace interior 130.
[0025]
The fuel 161 is supplied from the fuel supply device 108. When a solid such as coal is used as the fuel 161, the fuel 161 is injected into the furnace 130 using the fuel carrier air 154 described above. The fuel 161 charged into the furnace 130 mixes with the primary air 152 and the secondary air 153 forming the swirling flow 151 and burns near the slag outlet 102. Oxygen 156 is injected into the furnace 130 from the oxygen nozzle 106, and is directly mixed with the fuel 161 in the furnace 130. The oxygen 156 is supplied for the purpose of promoting the combustion of the fuel 161 and increasing the flame temperature.
[0026]
The ash 162 is supplied from the ash supply unit 109 and transported by the ash transport air 155. When adjusting the ash melting point, the melting point depressant 163 is put into the ash feeder 109 together with the ash 162 and mixed with the ash 162.
In this way, the ash 162 charged into the furnace 130 is melted while swirling together with the swirling flow 151 having a higher temperature due to the combustion of the fuel 161, and becomes a molten slag 165. The molten slag 165 flows down from the slag outlet 102, is cooled by the cooling water 164 of the slag recovery device 330 immediately below the slag outlet 102, and is collected as solid slag 166. In this embodiment, the slag collecting device 330 is a device for collecting slag as granulated slag, but is not limited to this.
[0027]
In addition, the ash fusion 100 described in FIG. 2 is an example, and the present invention is not limited to this.
[0028]
FIG. 3 shows a hardware configuration of the ash melting furnace control device 200 shown in FIG. In the figure, 201 is an output device such as a display or a printer, 202 is an input device such as a keyboard or a mouse, 203 is a central processing unit that executes ash melting furnace control, 204 is a storage device that stores data to be processed in the central processing unit, Reference numeral 205 denotes a communication control device that manages communication with an external system.
[0029]
Note that the hardware configuration of the ash melting furnace control device 200 described in FIG. 3 is an example, and the present invention is not limited to this.
[0030]
Here, returning to FIG. 1, a control method of the ash melting furnace will be described.
[0031]
The functions of the ash melting furnace control device 200 include a means 221 for receiving input of information indicating fuel properties and ash properties, a supply amount calculating means 222 for calculating a supply amount of each substance to be put into the ash melting furnace 100, an ash melting furnace. It has a calculating means 223 for predicting and calculating an index value indicating the operating state of the ash melting furnace 100, a measuring means 224 for measuring the operating state of the ash melting furnace 100, and a means 225 for comparing the index value with the operating state.
[0032]
As the means 221 for receiving the input of the fuel property and the ash property, a method of inputting by the input device 202 such as a keyboard, and a method of receiving the input from the outside by the communication control device 205 via a network such as the Internet and automatically transmitting the information to the ash melting furnace control device 200 It is conceivable that the input is performed manually. Since data on fuel properties and ash properties are usually acquired and managed regularly at a coal-fired power plant, these data are obtained from the coal-fired power plant via a network, and the ash melting furnace control device 200 , The input load of the fuel property and the ash property is reduced.
[0033]
Next, various supply amounts calculated by the supply amount calculation means 222 and items measured by the measurement function 223 of the operating state of the ash melting furnace 100 will be described.
[0034]
In addition, since the calculation method of the supply amount described below differs depending on the type of the ash melting furnace to be used, in the ash melting furnace to be used, each supply amount is obtained by using a calculation formula and numerical values obtained in advance by experiments and the like. Can be
[0035]
First, a fuel input amount 171 is set.
[0036]
In the present embodiment, a case where the heat load of the ash melting furnace 100 has a design value will be described. The initial value of the fuel input amount 171 is determined by dividing the design value of the heat load of the ash melting furnace 100 by the calorific value of the fuel 161.
[0037]
Next, regarding the setting of the combustion air amount 172, the combustion air amount 172 can be calculated by adding surplus air to the theoretical air amount obtained from the elemental analysis of the fuel 161.
[0038]
The combustion air amount 172 calculated in this way is totally controlled by the air conditioner 121 and divided into a primary air 152, a secondary air 153, a fuel conveying air 154, and an ash conveying air 155. Supplied to
[0039]
The flow rate 173 of the primary air 152 is controlled by the primary air regulator 122, and the flow rate 174 of the secondary air 153 is controlled by the secondary air regulator 123.
The fuel transfer air amount 175 is calculated according to the type of the fuel 161. For example, when using coal, the mass ratio of coal to the fuel transfer air 154 is generally about 0.5 to 1. Further, when a liquid fuel or a gaseous fuel is used, the fuel carrier air 154 is unnecessary. The calculated fuel delivery air amount 175 is controlled by the fuel delivery air regulator 124.
The ash carrying air amount 176 is calculated from the ash input amount 181 and the ash melting point depressant amount 182. It is desirable that the total of the ash input amount 181 and the ash melting point depressant amount 182 be supplied at a mass of 10 times or less the ash carrying air 155. The calculated ash transport air amount 176 is controlled by the ash transport air regulator 125.
[0040]
The initial value of the oxygen enrichment amount 183 is set according to the combustion speed of the fuel 161. The oxygen enrichment amount 183 is controlled by the oxygen regulator 126.
[0041]
From the above, it is desirable to set a design value according to the combustion speed of the fuel 161 as the initial value of each combustion condition such as the amount of injected fuel, the amount of combustion air, and the amount of oxygen enrichment. This is because the combustion state of the fuel 161 greatly depends on the method of supplying combustion air or oxygen. Therefore, first, combustion is performed at the initial value of each combustion condition, and each combustion condition is corrected based on the furnace temperature 187, the exhaust gas composition 188, and the exhaust gas temperature 189 measured by the operating state measuring means 223 of the ash melting furnace 100. It is desirable that the driving method be performed.
[0042]
In addition, an operating method in which the furnace temperature 187 is first raised under the combustion conditions when the ash 162 is not charged, and then the ash is charged while adjusting the combustion conditions is also conceivable.
[0043]
Next, the setting of the ash input amount 181 will be described.
[0044]
The ash input 181 has the following three limitations. The first is to maintain the furnace temperature 187 at or above the ash melting point. Second, the molten slag 165 flows down stably. Third, the ratio of the slag flow rate 186 to the total weight of the ash input quantity 181 and the ash melting point depressant quantity 182 is equal to or more than a certain value. There are three restrictions. In addition, the stable flow of the molten slag 165, which is the second limitation, can be monitored in the slag flow image data 185 measured by the flowing slag monitoring device 127. The slag flow rate 186, which is the third restriction, is also measured by the flowing slag monitoring device 127.
[0045]
However, there is a limit value due to these limitations, and the ash input amount 181 can be set freely as long as the limit value is not more than the limit value. Specifically, when coal is used as the fuel 161, it is said that the limit value of the ash input amount 181 is about 3 to 5 times the input amount of coal.
[0046]
In addition, the set ash charging amount 181 is controlled by the ash supply unit 109 and charged into the ash melting furnace 100.
[0047]
The ash melting point depressant 163 is used only when the melting point of the supplied ash 162 is higher than a preset design value.
[0048]
Here, an example of a calculation method of the ash melting point depressant amount 182 will be described.
[0049]
First, the basicity design value defined by the following equation is fixed.
[0050]
Basicity = (CaO + MgO + Na2O + K2O) / (SiO2 + Al2O3)
By fixing the melting point depressant 163 to CaO or the like, it is possible to calculate the amount 182 of the melting point depressant suitable for the design value of the basicity based on the ash composition obtained at the time of input.
[0051]
Then, the ash supplied from the ash supply unit 109 is sampled and the ash melting point is measured to correct the ash melting point depressant amount 182.
[0052]
The ash melting point depressant 163 is supplied from the ash supply unit 109 after being mixed with ash.
[0053]
The means 223 for predicting and calculating the index value indicating the operating state calculates the furnace temperature, the exhaust gas composition, the slag flow rate, and the like based on the calculated amount calculated by the supply amount calculating means 222 described above. The comparing means 225 compares the index value with the measurement data measured by the operating state measuring means 224, and when there is an abnormality in the operating state, recalculates the supply amount and adjusts the operating condition. Having. Note that the index value prediction calculation means 223 and the comparison means 225 will be described in detail with reference to FIG.
[0054]
Next, with reference to FIG. 4, a description will be given of a process flow of the ash melting furnace control method in the present ash melting furnace control device 200.
[0055]
As shown in the figure, first, fuel properties and ash properties are input. The fuel properties include at least the calorific value, ash content, ash melting point, fuel ratio, and elemental analysis. These properties are necessary for controlling the ash melting furnace for the following reasons.
[0056]
The calorific value is a property necessary to calculate the amount of heat to be put into the ash melting furnace, and the ash is the proportion of ash contained in the fuel itself in advance, and adjusts the amount of ash to be separately charged The ash melting point is a property required to calculate the amount of heat required to melt the ash. The fuel ratio is necessary when using a solid fuel, and is determined by the ratio of fixed carbon to volatile matter. The higher the value, the lower the burning rate due to the lower volatile content. Therefore, the fuel ratio is one of the properties necessary for adjusting the combustion conditions. Elemental analysis is a property required to calculate the amount of oxygen and air required for complete combustion.
[0057]
The initial setting value of the fuel input amount in the supply amount calculation (S1110) of each substance such as fuel, combustion air, oxygen, ash, ash melting point depressant, etc. to be input to the ash melting furnace can be calculated from the above fuel properties. it can.
[0058]
On the other hand, the ash properties include at least the ash melting point, the composition, and the particle size distribution. These properties are necessary to control the ash melting furnace for the following reasons. The ash melting point is a property required to calculate the calorific value of the ash melting, the composition is a property required to calculate the amount of the melting point depressant added by adjusting the ash melting point, and the particle size distribution is determined by the molten slag. This is a property required to affect the recovery rate. Specifically, particles having a particle diameter of less than 10 μm are easily scattered, and the recovery rate is reduced.
[0059]
Next, the supply amount of each substance to the ash melting furnace is calculated (S1110).
[0060]
The amount of fuel input includes a method of determining the amount of fuel input so that the thermal load to be supplied to the ash melting furnace is adjusted to the rated condition, and a method of setting the amount of fuel input. Further, the burning speed of the fuel decreases in the order of gas, liquid, and solid. As described above, in the case of solid fuel, the higher the fuel ratio, the lower the combustion speed.
[0061]
It should be noted that it is effective to pattern the initial values according to the burning speed of the fuel to be used for the input amounts of fuel, air and oxygen.
[0062]
As the combustion air amount, the amounts of oxygen and air necessary for complete combustion are calculated from the elemental analysis values of the fuel properties.
For example, a calculation example of the amount of oxygen necessary for complete combustion of a fuel composed of only carbon and hydrogen is shown below.
The reaction formula is
Carbon: C + O2 → CO2
Hydrogen: 2H2 + O2 → 2H2O
The amount of oxygen necessary for complete combustion of the fuel can be calculated by the following equation.
[0063]
Amount of oxygen required for complete combustion of fuel = (amount of oxygen required for combustion of carbon in fuel) + (amount of oxygen required for combustion of hydrogen in fuel)-(amount of oxygen contained in fuel)
The oxygen enrichment amount is adjusted and calculated in consideration of the combustion air amount. Oxygen is necessary to increase the temperature in the ash melting furnace.
[0064]
The amount of heat required for ash melting is proportional to the amount of ash input. Therefore, the limit value of the ash input amount is determined from the furnace temperature and the ash melting point.
[0065]
As an example of how to determine the ash input,
Under the condition of (total calorific value of fuel-total calorific value of ash)
Furnace temperature ≧ ash melting point
From the maximum value of the ash input amount that satisfies the above, the limit value of the ash input amount is obtained.
[0066]
Ash melting point depressants are added to adjust the melting point of the ash. There is known a method of predicting an ash melting point based on a ratio of an alkali metal oxide such as calcium, which is called basicity, and a metal oxide other than alkali such as silica and alumina, and calculating the amount of an ash melting point depressant.
[0067]
For example, if the basicity is represented by the following formula, the coal ash is 0.2 or less. By increasing this, the ash melting point is reduced.
[0068]
Basicity = (CaO + MgO + Na2O + K2O) / (SiO2 + Al2O3)
The combustion calculation (S1120) and the ash melting calorie calculation (S1130) are performed based on the supply amounts calculated in the supply amount calculation (S1110) of each of the above substances.
[0069]
Based on the results of the combustion calculation (S1120) and the ash melting calorie calculation (S1130), an index value indicating the operating state of the ash melting furnace is calculated (S1140). The index values include estimated furnace temperature, exhaust gas composition, slag flow rate, and the like.
[0070]
Next, the furnace temperature, which is one of the index values, is compared with the ash melting point, which is one of the input data indicating the ash properties (S1150). When the furnace temperature, which is an index value, exceeds the ash melting point, the ash can be melted at the respective supply amounts set in the above-described supply amount calculation (S1110). In that case, the process proceeds to the determination of the operating conditions of the ash melting furnace (S1160). Here, the furnace temperature may be set to be about 100 to 200 ° C. higher than the ash melting point to allow the molten slag to flow down stably.
[0071]
On the other hand, when the furnace temperature is lower than the ash melting point, the process returns to the above-described supply amount calculation (S1110), recalculates each supply amount, and further recalculates the index value (S1140). In this case, as a control method for increasing the furnace temperature, there is the following method.
[0072]
How to reduce the amount of ash input, increase the amount of fuel input and increase the amount of combustion air and oxygen accordingly, increase the amount of oxygen enrichment and reduce the amount of combustion air to reduce the total amount of gas And a method of reducing surplus air and surplus oxygen when introducing an air amount and an oxygen amount exceeding the theoretical air amount and the logical oxygen amount.
[0073]
However, in order to protect the furnace wall, the temperature of the furnace wall, that is, the temperature in the furnace is desirably set to 1600 ° C. or less.
[0074]
On the other hand, as a control method for lowering the ash melting point, there is a method of increasing the input amount of the ash melting point depressant. In addition, when a calcium compound is used as the ash melting point depressant, it is desirable that the input amount is 30% or less of the input amount of the ash. This is to bring the ash closer to a mineral form called anorthite. Further, when the calcium compound is supplied in an amount exceeding 30% of the input amount of the ash, the melting point of the ash may be increased.
[0075]
According to the above control method, the furnace temperature is controlled to be 1600 ° C. or lower and the furnace temperature is higher than the ash melting point.
[0076]
In the comparison between the furnace temperature and the ash melting point (S1150), when the furnace temperature becomes higher than the ash melting point, the supply amount calculated in the supply amount calculation (S1110) in that case and the index value calculation (S1140) The index value calculated in is determined as the operating condition of the ash melting furnace (S1160).
[0077]
Under these operating conditions, the ash melting furnace is actually operated, and the operating state of the ash melting furnace is measured and monitored (S1170). The data to be measured and monitored requires at least five items: furnace temperature, exhaust gas composition, exhaust gas temperature, slag flow rate, and slag flow rate image.
[0078]
The furnace temperature must always be higher than the ash melting point, and if it is lower than the ash melting point, it is necessary to correct the operating conditions. The exhaust gas composition is necessary to monitor the combustion state in the furnace, and when the operating conditions are constant and the oxygen concentration and the exhaust gas temperature fluctuate, it is necessary to correct the furnace operating conditions. The slag flow-down amount needs to be corrected if the slag flow-down amount continues to decrease in a state where there is no change in the operating conditions and the ash particle size distribution. For example, when the temperature in the furnace decreases and becomes lower than the ash melting point, there is a high possibility that the ash remains in the furnace. The slag flow-down image monitors a slag flow-down state by an image via a camera or the like. When the slag flow speed decreases in a state where the operating conditions are constant, it is necessary to correct the operating conditions.
[0079]
It is determined whether there is any abnormality in the operation state of the ash melting furnace based on the above measurement data of the operation state (S1180). Specifically, the index values such as the furnace temperature, the exhaust gas composition, and the slag flow rate calculated in the index value calculation (S1140) are compared with the actually measured values to determine whether there is any abnormality. I do. If the index value and the measured value deviate beyond a certain range, it is determined that there is an abnormality in the operating state.If the difference between the index value and the measured value is within a certain range, the operating state is abnormal. It is determined that there is not.
[0080]
If there is no abnormality in the operation state, the operation is continued under these operation conditions. In this case, it can be confirmed that there is no abnormality even from the stable flow of the slag (S1190).
[0081]
On the other hand, if there is an abnormality in the operation state, the flow returns to the above-described calculation of the supply amount (S1110). Calculation (S1140) is performed to correct the operating conditions. If the above measurement data is abnormal even after a certain period of time after correcting the operating conditions, reduce the ash charge, raise the furnace temperature, and discharge the slag remaining in the furnace. It is desirable to make it.
[0082]
The first embodiment of the present invention has been described above.
[0083]
Next, a second embodiment will be described. The second embodiment is a method in which an ash melting furnace 100 is installed in a coal-fired power plant, and coal ash discharged from the coal-fired power plant is continuously melted and collected as product slag.
[0084]
FIG. 5 shows an ash treatment method in which the ash melting furnace 100 described in the first embodiment is installed in a coal-fired power plant.
[0085]
The installed boiler 310 for burning coal has a burner 311 and an after-air port 312. The exhaust gas outlet 101 of the ash melting furnace 100 is connected to a boiler 310 through an exhaust gas duct 313.
[0086]
In this boiler 310, ash 162 discharged by burning coal is collected by dust collector 320. The ash 162 collected by the dust collector 320 is directly carried into the ash feeder 109 of the ash melting furnace 100. Of the ash 162 carried into the ash feeder 109, the amount calculated by the ash melting furnace control device is fed from the ash nozzle 107 into the furnace 130, where the ash is processed.
[0087]
In this embodiment, when coal is used as the fuel 161 of the ash melting furnace 100, it is possible to divert coal that is already held in a coal-fired power plant, and new capital investment such as coal storage equipment. Can be suppressed.
[0088]
Further, since the exhaust gas 157 discharged from the exhaust gas outlet 101 of the ash melting furnace 100 is composed of coal combustion gas, it is possible to use the exhaust gas treatment equipment of the coal-fired power plant.
[0089]
Coal-fired power plants use large amounts of coal, which emit large amounts of coal ash. For this reason, the operation system of the ash melting furnace which continuously melts coal ash discharged from a coal-fired power plant and collects it as slag is very efficient.
[0090]
Next, a third embodiment will be described. The third embodiment is an embodiment in which the molten slag produced in the first and second embodiments is commercialized according to the needs of the slag user.
[0091]
FIG. 6 shows the smelting furnace control method of the first embodiment (see FIG. 1), the slag collecting device selection mechanism 331, and the functions of the ash melting furnace control device 200, the slag specification input means 227 and the slag collecting device. It is a diagram to which a selection means 226 has been added.
[0092]
The slag specification input means 227 is a means for receiving input of information indicating the slag specification. A method of automatically inputting the information to the melting furnace control device 200 is considered.
[0093]
The slag collecting device selecting means 226 is a means for selecting a slag collecting device 330 for collecting slag according to the input slag specification. The selection result information selected by the slag collection device selection means 226 is output to the slag collection device selection mechanism 331, and is switched to the selected slag collection device 330.
Here, a method of commercializing a typical slag will be briefly described.
[0094]
The first is a method of collecting and commercializing granulated slag. Granulated slag is produced by dropping molten slag into water and rapidly cooling it. Granulated slag is generally about the size of a sand grain, and is glassy. The feature of granulated slag is that it can be easily manufactured, but it is difficult to secure the same strength as stone. Aggregates, roadbed materials, and the like can be considered as applications of the granulated slag.
[0095]
The second is a method of recovering as slag and commercializing it. The gradually cooled slag is crystallized because it is slowly cooled over one day or more, thereby increasing the strength of the slag. In the method for producing the gradually cooled slag, the molten slag is gradually cooled by water spray, air, or the like, and the cooling rate is desirably 50 degrees / hour or less. Applications include stone and roadbed materials.
[0096]
Others include fiber materials. If the production equipment for glass wool or rock wool is applied to the molten slag of coal ash, the molten slag of coal ash can be recovered as a fiber material. As an application, a heat insulating material and the like can be considered.
[0097]
As described above, the method of cooling and collecting the molten slag differs depending on the use of the slag.
[0098]
Next, an example of the type of the slag collection device 330 and an outline thereof will be described.
[0099]
The slag recovery device for granulated slag is composed of a water tank and a slag conveyor. The water tank is filled with water, and the molten slag 165 is dropped into the water in the water tank. The molten slag 165 is cooled in water and becomes sandy granulated slag. The granulated slag is collected by a slag conveyor or the like. By storing the slag conveyor in the water tank, it is possible to package each device of this apparatus.
[0100]
The slag recovery device for slow cooling slag is composed of a slag cooling tank and a slag conveyor. The molten slag 165 is dropped on a slag conveyor and collected while cooling at about 50 degrees / hour with air or the like. By installing a slag conveyor in the cooling tank, it is possible to package each device of this device.
[0101]
A slag recovery device for a fiber material includes a fiberization device and a fiber recovery conveyor. The fiberizing device has a rotating roller or the like used for rock wool or glass wool. By setting the fiberizing device and the fiber recovery conveyor on a cart or the like, it is possible to package each device of the present device.
[0102]
The slag collection device 330 is packaged as described above, and a different package is installed immediately below the slag outlet according to the slag specification, and the form of the collected slag is made variable.
[0103]
In the present embodiment, a plurality of packaged slag collection devices 330 are provided for each slag application, and the slag collection device 330 is selected according to the slag application. As a method of switching the slag collecting device 330 to the selected slag collecting device, every time the slag collecting device 330 is switched, the selected slag collecting device 330 is moved directly below the slag extracting port 102 of the ash melting furnace 100 and installed. There is a way to do that. There is also a method in which a transport path connecting the slag outlet 102 and the plurality of slag recovery devices 330 is provided, and the molten slag flows down to the selected slag recovery device 330 by controlling the transport path. In the present embodiment, a plurality of slag collecting devices 330 are used. However, a single slag collecting device 330 that can cope with a plurality of slag cooling / collecting methods may be used.
[0104]
Next, with reference to FIG. 7, a process flow of a control method of the ash melting furnace for collecting the ash as the product slag will be described.
[0105]
The flow of the processing shown in FIG. 7 is the same as the processing flow of the control method of the ash melting furnace shown in FIG. 4 of the first embodiment from S1110 to S1190. That is, a process for making Here, the description will be focused on the process of commercializing the slag after S1200.
[0106]
In the ash melting furnace control device 200, when there is no abnormality in the operation state, the slag flows down stably (S1190), whereby the ash becomes molten slag. Here, in order to commercialize the molten slag, a slag user inputs slag product specifications. The product specifications of the slag include, for example, product specifications such as aggregate, roadbed material, stone, roadbed material, and heat insulating material.
[0107]
The slag recovery device selection means 226 selects the slag recovery device 330 to be used from the input slag specifications and the molten slag 165 as the raw material (S1200). As an example of the selection, when the product use of the aggregate and the roadbed material is input, the slag collecting device for the granulated slag is selected to collect as the granulated slag. In addition, when the use of stone and roadbed products is input, the slag collection device for slowly cooled slag is selected to recover as slowly cooled slag. The slag recovery device for the fiber material is selected to recover the slag.
[0108]
Next, using the selected slag recovery device 330, the molten slag 165 is cooled and recovered (S1200). It is determined whether the collected slag satisfies the required specifications of the slag (S1210). If it meets the required specifications for slag, it is sold to slag users as product slag. On the other hand, when the required specification of the slag is not satisfied, the process returns to the supply amount calculation (S1110), recalculates the supply amount of the ash melting furnace, and adjusts the operating conditions of the ash melting furnace. Here, the state of the product slag depends on factors such as the temperature and viscosity of the molten slag 165 at the time of dropping from the slag outlet. The required specifications of the product slag are defined by a standard (such as JIS standard) determined for a use used as a product and a required specification determined by a slag user.
[0109]
The use of the product slag can be considered as aggregate, roadbed material, stone, fiber material, soil improvement material, seawall construction material, fishing reef, and the like.
[0110]
In the present embodiment, the ash melting furnace equipped with a plurality of slag recovery devices according to the specifications of the slag, the slag melted in the ash melting furnace, according to the needs of the slag user, the product of multiple specifications flexibly There is an effect that slag can be manufactured.
[0111]
The third embodiment has been described above.
[0112]
It should be noted that the present invention is not limited to the embodiments described above, and various modifications are possible, and it is needless to say that these are also included in the scope of the present invention.
[0113]
【The invention's effect】
As described above, according to the present invention, when coal ash discharged from a coal-fired power plant is melted and turned into slag, the properties of the fuel and ash used are automatically controlled, and the ash is automatically controlled. An ash melting device capable of stably operating a melting furnace can be provided. Furthermore, there is an effect that the added value of slag is increased by adjusting the properties of slag to market demand.
[0114]
Therefore, according to the present invention, ash can be collected as product slag, which is a valuable resource, and reduction of ash currently disposed in landfill can be expected.
[Brief description of the drawings]
FIG. 1 is a diagram showing a control method of an ash melting device according to a first embodiment of the present invention.
FIG. 2 is a view showing the ash melting furnace shown in FIG. 1;
FIG. 3 is a diagram showing a configuration of the ash melting furnace control device shown in FIG. 1;
FIG. 4 is a diagram showing a flow of a control method of the ash melting furnace shown in FIG.
FIG. 5 is a diagram showing a method for controlling an ash melting furnace according to a second embodiment of the present invention.
FIG. 6 is a diagram showing a method for controlling an ash melting furnace according to a third embodiment of the present invention.
FIG. 7 is a diagram showing a flow of a control method of the ash melting furnace shown in FIG.
[Explanation of symbols]
100 ash melting furnace, 101 exhaust gas outlet, 102 slag outlet, 103 primary air nozzle, 104 secondary air nozzle, 105 fuel nozzle, 106 oxygen nozzle, 107 ash nozzle, 108 fuel Feeder, 109: Ash feeder, 110: Water tank, 121: Air regulator, 122: Primary air regulator, 123: Secondary air regulator, 124: Fuel transport air regulator, 125: Ash transport air regulator , 126: oxygen regulator, 127: slag flow-down monitoring device, 128: temperature measuring device, 129: exhaust gas analyzer, 130: inside the furnace, 151: swirling flow, 152: primary air, 153: secondary air, 154 ... Fuel transport air, 155 ash transport air, 156 oxygen, 157 exhaust gas, 161 fuel, 162 ash, 163 melting point depressant, 164 cooling water, 165 molten slag, 1 6: solid slag, 171: fuel input, 172: combustion air, 173: primary air, 174: secondary air, 175: fuel transport air, 176: ash transport air, 181: ash input 182 ash melting point depressant, 183 oxygen enrichment, 185 slag flow image data, 186 slag flow, 187 furnace temperature, 188 exhaust gas composition, 189 exhaust gas temperature, 190 slag recovery device Selection information, 200: Ash melting furnace control device, 201: Display device, 202: Input device, 203: Central processing device, 204: Storage device, 205: Communication control device, 310: Boiler, 311: Burner, 312: After airport 313: exhaust gas duct, 320: dust collector, 330: slag collecting device, 331: slag collecting device selection mechanism.

Claims (10)

In an ash melting device that manufactures slag by melting ash,
An ash melting furnace for melting ash, a slag collecting device for collecting slag, and a control device for controlling the ash melting furnace,
The control device includes: first input receiving means for receiving input of information indicating fuel properties;
Second input receiving means for receiving input of information indicating the ash property;
Information indicating the fuel property, and, using the information indicating the ash property, first calculating means for calculating the supply amount of the substance supplied to the ash melting furnace,
Second calculating means for predicting and calculating one or more index values indicating an operating state of the ash melting furnace which will occur based on the supply amount;
Measuring means for measuring the operating state of the ash melting furnace,
Comparing means for comparing one or more index values calculated by the second calculating means and the measurement result measured by the measuring means,
The ash melting apparatus, wherein the comparing means causes the first calculating means to perform recalculation for obtaining a supply amount for bringing the ash melting furnace into a target operation state based on a result of the comparison. . The ash melting device according to claim 1,
The ash melting device, wherein the first input receiving means and the second input receiving means have a function of receiving from outside via a network. The ash melting device according to claim 1,
An ash melting apparatus characterized in that the supply amounts of the substances calculated by the first calculation means are a fuel input amount, a combustion air amount, an oxygen enrichment amount, an ash input amount, and an ash melting point depressant amount. The ash melting device according to claim 1,
A plurality of the slag collection devices are provided corresponding to a plurality of specifications of the slag to be collected,
The control device includes a third input receiving unit that receives input of information indicating slag specifications, and a unit that selects a slag collection device corresponding to the received slag specifications,
Ash melting equipment characterized by the following. In a control device for controlling an ash melting furnace that produces slag by melting ash,
First input receiving means for receiving input of information indicating fuel properties;
Second input receiving means for receiving input of information indicating the ash property;
Information indicating the fuel property, and, using the information indicating the ash property, first calculating means for calculating the supply amount of the substance supplied to the ash melting furnace,
Second calculating means for predicting and calculating one or more index values indicating an operating state of the ash melting furnace which will occur based on the supply amount;
Based on the output of a sensor provided in the ash melting furnace, measuring means for measuring the operating state of the ash melting furnace,
Comparing means for comparing one or more index values calculated by the second calculating means and the measurement result measured by the measuring means,
The comparing means causes the first calculating means to perform a recalculation based on a result of the comparison so that the supply amount is such that the ash melting furnace is operated according to a target operation state. Control device for melting furnace. In a control device for controlling an ash melting furnace that produces slag by melting ash,
First input receiving means for receiving input of information indicating fuel properties;
Second input receiving means for receiving input of information indicating the ash property;
Third input receiving means for receiving input of information indicating the specifications of the slag;
Selection means for selecting a plurality of slag recovery devices provided in the ash melting furnace,
Information indicating the fuel property, and, using the information indicating the ash property, first calculating means for calculating the supply amount of the substance supplied to the ash melting furnace,
Second calculating means for predicting and calculating one or more index values indicating an operating state of the ash melting furnace which will occur based on the supply amount;
Based on a sensor provided in the ash melting furnace, measuring means for measuring the operating state of the ash melting furnace,
Comparing means for comparing one or more index values calculated by the second calculating means and the measurement result measured by the measuring means,
The comparing means causes the first calculating means to perform a recalculation based on a result of the comparison so that the supply amount is such that the ash melting furnace is operated according to a target operation state.
The control device for an ash melting furnace, wherein the selection means selects a slag recovery device corresponding to the accepted slag specification and outputs information on a selection result. In a control method of an ash melting furnace for manufacturing slag by melting ash,
Receiving input of information indicating fuel properties;
Accepting input of information indicating ash properties;
Calculating the supply amount of the substance supplied to the ash melting furnace using the information indicating the fuel property, and the information indicating the ash property,
Predicting and calculating one or more index values indicative of an operating state of the ash melting furnace that will occur based on the supply amount;
Measuring the operating state of the ash melting furnace,
Comparing at least one index value calculated by the step of predicting and calculating the index value with a measurement result measured by the step of measuring the operating state;
Based on the result of the comparison in the comparison step, a step of recalculating a supply amount for setting the supply amount in which the ash melting furnace is operated in a target operation state, by the information processing device,
A method for controlling an ash melting furnace. In the control method of the ash melting furnace according to claim 5,
Receiving input of information indicating the specifications of the slag;
Selecting a slag collection device according to the specifications of the slag, and executing the information processing device,
A method for controlling an ash melting furnace characterized by the following. An information processing device for controlling an ash melting furnace that produces slag by melting ash,
Receiving input of information indicating fuel properties;
Accepting input of information indicating ash properties;
Calculating the supply amount of the substance supplied to the ash melting furnace using the information indicating the fuel property, and the information indicating the ash property,
Predicting and calculating one or more index values indicative of an operating state of the ash melting furnace that will occur based on the supply amount;
Measuring the operating state of the ash melting furnace,
Comparing at least one index value calculated by the step of predicting and calculating the index value with a measurement result measured by the step of measuring the operating state;
Recalculating a supply amount for the ash melting furnace to be operated in a target operation state based on a result of the comparison in the comparison step. The program according to claim 5,
A program for causing the information processing device to execute a step of receiving input of information indicating a slag specification, and a step of selecting a slag collection device according to the slag specification and outputting a selection result.

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