JP5534670B2 - Simple estimation method of spontaneous ignition, solid fuel production method, and solid fuel production facility - Google Patents

Description

  The present invention relates to a solid fuel obtained by carbonizing organic sludge raw materials such as sludge treated in a sewage treatment plant (hereinafter referred to as sewage sludge), human waste sludge, livestock manure sludge, agricultural settlement drainage sludge, etc. The present invention relates to a production method and a simple estimation method for spontaneous ignition of carbides when carbonizing organic sludge.

Technology development related to effective use of organic sludge has been actively carried out in response to increasing environmental problems. Regarding the effective use of organic sludge, the technology to make carbonized sludge by further developing the use of green farmland and construction materials by composting has been developed.
In Patent Document 1, dry sewage sludge is granulated, carbonized at 300 to 600 ° C. for 4 to 22 minutes with a rotary kiln in an air shut-off atmosphere, and then immediately cooled, as a fuel substitute for boilers, cement kilns, etc. It is disclosed to use.
JP 2000-265186 A

In Patent Document 1, paper sludge, food sludge, and sewage sludge are considered to be uniform. Actually, however, these organic sludges are discharged, treated (with or without digestion process), seasonal The properties are greatly different due to fluctuations, and if uniform drying and carbonization are performed, stable quality as a solid fuel cannot be ensured. Above all, it is extremely important for safety to ensure stable quality in terms of pyrophoricity. Here, spontaneous ignition means the property of spontaneous ignition due to chemical causes such as oxidation heat, decomposition heat, and adsorption heat. Substances with high pyrophoric potential may generate heat or store heat during storage or transportation, which may lead to ignition, so sufficient safety management is required.
Furthermore, for quality control related to pyrophoric properties, it is necessary to know the pyrophoric properties of carbides as products, but there has been no inexpensive and simple method.
Accordingly, a main problem of the present invention is to provide a method for easily and inexpensively knowing the spontaneous ignition of carbides when carbonizing a dried organic sludge in a carbonization furnace. Another object is to provide a method for producing a solid fuel having a stable quality in terms of spontaneous ignition by using organic sludge as a raw material.

A simple method for estimating pyrophoric properties for solving the above problem is that when organic sludge is carbonized in a carbonization furnace, the carbide discharged from the carbonization furnace is passed through a gas having a predetermined oxygen concentration while passing through a predetermined temperature condition. Hold for a specified period of time and measure at least one of the amount of oxygen consumed and the rate of temperature rise of the carbide, and estimate pyrophoricity based on whether this measured value exceeds a specified safety standard value It is characterized by this .
Here, the consumed oxygen amount is a difference in oxygen concentration before and after aeration to the carbide. Strictly speaking, the flow rate of the gas changes before and after the aeration to the carbide, but the amount of change is slight, so that the amount of oxygen consumed can be approximately determined from the difference in oxygen concentration. The temperature rise rate is a value obtained from the temperature difference that rises per unit time.

  As a result of earnest research on a method that can easily estimate pyrophoric properties, the present inventors have found that there is a correlation between the amount of oxygen consumed and the exothermic rise temperature, and between the temperature rise rate of the carbide and the exothermic rise temperature. It has been found that there is a correlation, and the first invention has been made. The exothermic rising temperature indicates how much the temperature rises due to the heat generated by the oxidation reaction of the carbide when the carbide is held for a predetermined time under a predetermined temperature condition while passing a gas having a predetermined oxygen concentration. Yes, it is an index of pyrophoricity. Therefore, by monitoring at least one of the consumed oxygen amount and the temperature rise rate of the carbide, the spontaneous ignition of the carbide can be monitored. As will be described later, both the amount of oxygen consumed and the temperature rise rate of the carbide can be easily measured without using an expensive measuring device.

And this invention is the method of manufacturing the carbide | carbonized_material as solid fuel by carbonizing organic sludge in a carbonization furnace,
The atomic ratio H / C of hydrogen and carbon in the carbide discharged from the carbonization furnace is obtained, and at least one of the carbonization temperature and the carbonization time in the carbonization furnace is set so that the atomic ratio H / C becomes a predetermined control value. While adjusting
The carbide discharged from the carbonization furnace is held for a predetermined time under a predetermined temperature condition while ventilating a gas having a predetermined oxygen concentration, and at least one of the consumed oxygen amount and the temperature rise rate of the carbide is measured. When the measured value exceeds a predetermined safety reference value , the carbon atomization in the carbonization furnace is performed by setting a higher atomic ratio H / C as a new control value so that the measured value is less than the safety reference value. Adjust the temperature or carbonization time,
This is a method for producing a solid fuel.
In this way, by measuring at least one of the amount of oxygen consumed and the temperature rise rate of the carbide, and adjusting the carbonization conditions so that the measured value is below a predetermined safety standard, stable quality with respect to pyrophoricity It becomes possible to produce solid fuel.

Furthermore, in the present invention, a carbonization furnace for carbonizing organic sludge,
A carbide extraction device for extracting the carbide discharged from the carbonization furnace;
From the carbide supply port to which all or a part of the carbide extracted by the carbide extraction device is supplied, an air supply port, an air extraction port, a temperature measuring device for measuring the temperature of the carbide, and the air extraction port A measuring device having at least one of oxygen concentration measuring devices for measuring the oxygen concentration of discharged air;
Equipped with a,
In the production of the solid fuel, the atomic ratio H / C of hydrogen and carbon in the carbide discharged from the carbonization furnace is obtained, and the carbonization temperature in the carbonization furnace is set so that the atomic ratio H / C becomes a predetermined control value. And adjusting at least one of the carbonization time,
The measurement device measures at least one of the amount of oxygen consumed and the temperature rise rate of the carbide, and when the measured value exceeds a predetermined safety reference value, a higher atomic value is set so that the measured value is not more than the safety reference value. By adjusting the number ratio H / C as a new control value, the carbonization temperature or carbonization time in the carbonization furnace is adjusted.
A solid fuel production facility characterized by the construction is also proposed.

  As described above, according to the present invention, advantages such as being able to know the pyrophoric properties of carbides at low cost and easily and producing a solid fuel with stable quality are brought about.

Hereinafter, an embodiment of the present invention will be described in detail.
<Examples of manufacturing equipment>
FIG. 1 shows an example of a production facility for solid fuel. The dehydrated organic sludge 1 dehydrated by a belt press or the like is supplied to a dryer 10. The dehydrated organic sludge supplied to the dryer 10 is dried by hot air supplied from the first hot air furnace 12 to the dryer 10. The dried dried sludge 2 is supplied to the carbonization furnace 20. The carbonization furnace 20 is supplied with hot air generated under the fuel in the second hot air furnace 22 to indirectly heat the dried sludge, and carbonization is performed at a predetermined carbonization temperature and carbonization time. The combustion air supplied to the second hot air furnace 22 is heated by heat exchange with a part of the hot air discharged from the carbonization furnace 20 in the second heat exchanger 18. Carbide (carbonized sludge) is sequentially discharged from the carbonization furnace 20. After cooling, the carbide is granulated to a predetermined particle size by a granulator (not shown), preferably a compression granulator, from the viewpoint of improving handling properties, etc., to obtain a solid fuel. The granulation may be performed before carbonization, and as the granulator, a mixing granulator, a compression granulator, or the like is applicable, but an extrusion granulator is particularly preferable.

  The dry distillation gas generated in the carbonization furnace 20 is supplied to the first heat exchanger 16 after being combusted in the reburning furnace 14 under the blowing of combustion air and fuel, and is separately supplied to the first heat exchanger 16. The heat exchange with the exhaust gas is used as a heating source for the hot air for drying of the dryer 10. The exhaust gas of the dryer 10 is heated by receiving heat from the reburning furnace 14 in the first heat exchanger 16 and then supplied to the first hot air furnace 12 to raise the temperature under the blowing of combustion air and fuel. Then, it is supplied to the dryer 10 as hot air for drying. Further, a part of the exhaust gas of the dryer 10 is guided to the dehumidifying tower 24 and is subjected to combustion treatment at a high temperature in the reburning furnace 14 after the humidity is reduced.

  As shown in FIG. 2, it is possible to directly supply a part of the exhaust gas of the dryer 10 to the reburning furnace without using the dehumidifying tower 24.

  These facilities are examples, and other forms can naturally be adopted. Moreover, there is no limitation on the type of the dryer 10 or the carbonization furnace 20. Incidentally, types of the carbonization furnace 20 include a rotary kiln, a screw type, a fluidized bed type, and the like. In the dryer 10, the outlet moisture is preferably 10 to 40%, particularly 20 to 30%.

  Carbide discharged from the carbonization furnace is preferably measured for pyrophoricity using a measuring device 30 shown in FIG. This measuring device 30 is filled with a certain amount of carbide into a sealed thermostatic chamber 33 having a carbide supply port 31 and a carbide discharge port 32 and is supplied from a gas blowing port 35 at a predetermined temperature and a predetermined oxygen concentration (for example, a temperature of 105 ° C., oxygen A gas having a concentration of 21% by volume) is quantitatively supplied and discharged (naturally discharged) from the gas outlet 36. Characteristically, the flow rate 40 for measuring the flow rate of the gas supplied from the gas inlet 35, the oxygen concentration meter 41 for measuring the oxygen concentration, and the oxygen concentration of the gas discharged from the gas outlet 36 are shown. An oxygen concentration meter 42 for measuring is provided, and a thermometer 43 for measuring the temperature of the carbide is appropriately installed. Note that the oxygen concentration meter 41 can be omitted when the oxygen concentration is 1, such as when air is used as the gas to be supplied. In the illustrated example, a part of the carbide discharged from the carbonization furnace 20 is automatically sampled by a transfer device 50 such as a screw conveyor and supplied to the measuring device 30, and the remaining non-sampling portion passes through the measuring device. Without being supplied to a subsequent process such as cooling. After the measurement, the carbides supplied to the measuring device 30 may be mixed and mixed in non-sampling portions or may be recovered individually.

  In addition, although the said measuring apparatus 30 measures the pyrophoric property of carbide | carbonized_material batchwise, it is not restricted to a batch system, The transfer apparatus, such as a screw conveyor, is provided in the measuring apparatus 30, and the carbide | carbonized_material supply port 31 is used. A continuous system may be used in which the supplied carbide is sequentially transferred to the carbide discharge port 32 by a transfer device at a predetermined transfer speed.

<Example of manufacturing method>
In the case of solid fuel obtained by drying and carbonizing organic sludge such as sewage sludge, it is extremely important to ensure stable quality, and the degree of carbonization, which is important for such quality control, is important. One index is the atomic ratio H / C of hydrogen (H) and carbon (C). As described above, the properties of organic sludge such as sewage sludge vary greatly depending on the form of discharge, treatment method (with or without digestion process), and seasonal variations, but are discharged from the carbonization furnace 20 during the production of solid fuel. The carbon number ratio H / C of the carbide to be obtained is determined, and the carbonization temperature and carbonization time in the carbonization furnace 20 so that this value becomes a predetermined control value (including not only a single value but also a numerical range) ( By adjusting at least one of the (residence time in the furnace) (controlling the carbonization conditions), a solid fuel having a desired carbonization degree can be obtained reliably. Control based on the atomic ratio H / C can be performed continuously or intermittently. Hereinafter, a method for obtaining the atomic ratio H / C of carbide, a method for determining a predetermined control value, and a method for adjusting the carbonization temperature and the carbonization time will be described in order.

(Simple estimation method of atomic ratio H / C)
When the carbonization conditions are adjusted according to the sludge properties to stabilize the quality, the frequency of adjustment increases, and therefore the method for obtaining the atomic ratio H / C of the carbide is preferably simple. Accordingly, the following simple estimation method of the atomic ratio H / C is proposed.
That is, the atomic ratio H / C in the carbide has a correlation with the residual ratio of the combustible component of the carbide, and also has a correlation with the calorific value per unit combustible mass of the carbide. FIG. 3 is a graph showing the relationship between the remaining combustible content of carbide and the atomic ratio H / C, and FIG. 4 shows the calorific value per unit combustible mass of carbide and the atomic ratio H / C of carbide. It is the graph showing the relationship with. The correlations seen in these graphs appear if the type of sludge is the same.
Therefore, these correlations (when obtaining the correlation, hydrogen and carbon are measured by a method based on JIS M 8812 "Coal and cokes-industrial analysis method", and the atomic ratio H / C can be calculated. By simply measuring at least one of the residual flammable fraction and the calorific value per unit flammable mass in the production of solid fuel, the atomic ratio H / C of the resulting carbide can be simplified. Can be requested.

  Here, the flammable residual rate indicates how much the flammable component contained in the raw material before carbonization remains after carbonization, and is a substantially constant value under the same raw material and the same carbonization conditions. It will be. The residual combustible fraction can be measured, for example, by the following two methods. Of course, it can also be measured by other methods.

The first method measures the total mass (anhydrous basis) and combustible content of dry matter supplied to the carbonization furnace, and the total mass (anhydrous base) and combustible content of the carbide discharged from the carbonization furnace, respectively. The total mass A of the combustible component in the dried product is calculated from the above, the total mass C of the combustible component in the carbide is calculated from the latter, and these A and C are substituted into the following formula (2) to thereby calculate the residual ratio of the combustible component. Is what you want.
Combustible fraction remaining rate (%) = C / A × 100 (2)

  In this first method, it is necessary to measure the total mass of dry matter and the total mass of carbide, and if it is a test, there is no problem, but it is difficult to measure accurately during operation.

Therefore, as a second method, based on the assumption that the mass of ash is unchanged before and after carbonization, dry matter and a part of the carbide are sampled automatically or manually, and the ash content b (% ) And combustible component a (%), and ash content y (%) and combustible component x (%) of the carbide sample, respectively, and substituting these values into the following formula (3) to calculate the residual combustible fraction Propose to do.
Combustible fraction remaining rate (%) = (b × x) / (a × y) × 100 (3)

Moreover, the calorific value per unit flammable mass of the carbide is a value that is substantially constant under the same raw material and the same carbonization conditions, for example, a part of the carbide is sampled automatically or manually, Using the calorific value measurement device in accordance with JIS M 8814 “Coal and cokes—Measurement method of total calorific value and calculation method of true calorific value” with respect to the carbide sample The calorific value E is measured and can be obtained by substituting these D and E into the following formula (4). Of course, it can also be measured by other methods.
Calorific value per unit flammable mass (kcal / kg) = E / D (4)

(Selection of H / C management values)
Although the management value of atomic ratio H / C and the specific selection method of carbonization temperature and carbonization time can be determined suitably, for example, the following method can be used suitably.
As an example of organic sludge, when solid fuel obtained by drying and carbonizing sewage sludge is used as a substitute for fossil fuel, it is an environmental problem to consider the energy consumed in the process of obtaining the fuel from the viewpoint of CO ₂ emissions. Is necessary to solve the problem. That is, as shown in FIG. 5, electric power and fossil fuel (for example, kerosene) are consumed as energy required for drying and carbonization of sewage sludge. These can be expressed as CO ₂ emissions associated with power consumption (1) and CO ₂ emissions associated with fossil fuel consumption (2). On the other hand, if carbide of sewage sludge is used as an alternative fuel, that amount will be the CO ₂ reduction amount (3). That is, from the viewpoint of reducing CO ₂ emissions, it is desirable that (1) + (2) <(3).

Here, although (1) and (2) vary depending on the manufacturing process, it has been found that the process of FIG. 1 has the relationship of FIG. Fig. 6 shows the relationship between the water content of sewage sludge to be dried (dehydrated sludge: sludge after dehydration), the combustible content of the sewage sludge, and the atomic ratio H / C of the hydrogen content and carbon content of the solid fuel. The CO ₂ reduction (3) by using the solid fuel is balanced against the CO ₂ emissions ((1) + (2)) associated with the use of electric power and (fossil) fuel. The points to be (equal) are plotted for each atomic ratio H / C. Such a first correlation is obtained in advance experimentally or by estimation calculation. The moisture can be measured by a method based on JIS M 8812 “Coal and cokes—industrial analysis method”.

And by utilizing this first correlation, the amount of CO ₂ emission is taken into consideration based on the moisture of the organic sludge that is actually subject to drying and the combustible content of the organic sludge (for example, the above-mentioned) The atomic ratio H / C of the hydrogen content and the carbon content in the solid fuel to be obtained can be selected so that the relationship (1) + (2) <(3) is satisfied.

  Solid fuel (carbide) to obtain the control value of the atomic ratio H / C of the hydrogen content and carbon content in the solid fuel within the selection range based on the first correlation or regardless of the first correlation ) Can be selected as appropriate according to the characteristics. For example, when co-firing with coal in a coal-fired power plant, it is desirable that the control value of the atomic ratio H / C is desirably 0.8 to 1.8, and that 1.0 to 1.6 is particularly suitable. doing. The atomic ratio H / C of coal varies depending on the production area, but is about 0.6 to 1.0, and the average is about 0.8. In this regard, the prior art document is presumed from various numerical values that the atomic ratio H / C is assumed to be 0.6 or less, although the conditions are considerably unknown. In this sense, the value of the atomic ratio H / C in the above range is quite high.

FIG. 7 is a correlation graph between H / C and fuel ratio (weight ratio with respect to volatile content of fixed carbon). The fuel ratio increases as H / C decreases, and the combustibility as a solid fuel deteriorates and nitrogen is reduced. The amount of oxide produced also increases. However, when co-firing with coal in a coal-fired power plant, high combustibility is required. The fuel ratio of coal varies depending on the production area, but it is about 1.0 to 2.4 (on the average about 1.6). The fuel ratio is 1.6 or less for solid fuel equivalent to or better than coal. More desirably, the fuel ratio should be 1.0 or less.
Furthermore, if the atomic ratio H / C is high, high blackness cannot be obtained, which is greatly different from the blackness of coal, and there is a difficulty in giving anxiety in terms of appearance.

  Moreover, when making a carbide | carbonized_material into a solid fuel, it is so desirable that the emitted-heat amount is high.未 For undigested sewage sludge from urban sewage treatment plants, by changing the carbonization temperature and carbonization time, we obtained various changes in the atomic ratio H / C of hydrogen and carbon in organic sludge, About these, when the emitted-heat amount was investigated, the result shown in FIG. 8 was obtained. From this result, the calorific value greatly depends on the atomic ratio H / C, and decreases rapidly when the atomic ratio H / C is approximately 1.0 or less. There is little decrease in Therefore, when importance is attached to the calorific value, it is desirable to select the management value of the atomic ratio H / C within the range of more than 1.0 and 1.8 or less.

  Furthermore, when the carbide is used as a solid fuel, it is extremely important for safety to ensure a stable quality in terms of pyrophoricity. FIG. 9 shows the relationship between H / C and the rate of increase in heat generation. In the region where H / C is about 1.2 to 1.6, the rate of increase in heat generation decreases and increases with a decrease in H / C. I understand that And after H / C reaches a peak in the region of about 0.7 to 0.9, this time, it starts to decrease. Therefore, in order to suppress spontaneous ignition, it is desirable to select the control value of the atomic ratio H / C within a range as large as possible from 0.7 to 0.9, preferably 1.2 or more.

  However, absolute spontaneous ignition cannot be monitored and managed only by correlation between spontaneous ignition and the atomic ratio H / C. Therefore, as a method of solving this, the amount of oxygen consumed and the temperature rise rate of the carbide when the carbide discharged from the carbonization furnace is held for a predetermined time under a predetermined temperature condition while a gas having a predetermined oxygen concentration is vented. A method is proposed in which at least one of them is measured, and the spontaneous ignition is estimated based on whether or not the measured value exceeds a predetermined safety standard value.

  The oxygen concentration of the gas used can be in the range of 10 to 100%, and it is usually preferable to use air (oxygen concentration of about 21%) for convenience. The temperature of the gas used can be from room temperature to about 500 ° C., and particularly preferably from 50 to 150 ° C. The holding time can be about 10 minutes to 50 hours, particularly preferably 30 minutes to 24 hours. Furthermore, the predetermined safety standard value can be determined by conducting a test in advance, and can be set to, for example, an oxygen consumption amount of 8% or less, or a temperature increase rate of 5 ° C./hr or less.

  For example, the apparatus shown in FIG. 12 may be used to measure the oxygen consumption amount and the temperature rise rate. When measuring the oxygen consumption amount in the apparatus, the gas concentration is determined from the oxygen concentration of the gas supplied from the gas inlet 35. The oxygen concentration of the gas discharged from the extraction port 36 is subtracted to obtain. Further, when measuring the temperature increase rate, the temperature measured by the thermometer 43 is obtained from the temperature increased per unit time.

  FIG. 10 is a graph showing the relationship between the amount of oxygen consumed and the exothermic rise temperature, and FIG. 11 is a graph showing the relationship between the temperature rise rate of the carbide and the exothermic rise temperature. The correlations seen in these graphs appear if the type of sludge is the same. The exothermic rise temperature is an index of pyrophoricity, and the higher the value, the higher the pyrophoricity. Therefore, measure and monitor at least one of the oxygen consumption and the temperature rise rate of carbides. In this way, the pyrophoric properties of carbides can be monitored.

As a result of monitoring, when the measured value of at least one of the consumed oxygen amount and the temperature rise rate exceeds a predetermined safety reference value, the control value of the atomic ratio H / C is set so that the measured value is equal to or less than the safety reference value. Is selected, that is, by setting a higher atomic ratio H / C as a new control value, the carbonization conditions described later are adjusted. Such feedback control makes it possible to ensure stable quality in terms of spontaneous ignition.
As can be seen from this, the management value of the atomic ratio H / C can be changed continuously or stepwise without being fixed.

(Selection of carbonization conditions)
On the other hand, when selecting the carbonization conditions, a second correlation between the carbonization time for carbonization, the carbonization temperature, and the atomic ratio H / C of the hydrogen content and the carbon content in the solid fuel is obtained in advance, and the selected atoms are selected. Based on the control value of the number ratio H / C, the carbonization time and the carbonization temperature are selected under this second correlation. In the carbonization furnace, carbonization is performed under this selection condition.

  This second correlation is low in dependence on the flammable content of sewage sludge, and can be determined uniquely by a carbonization experiment using a carbonizer within a range where the moisture of the dried sludge is 10% or less. is there. When the water content exceeds 10%, it is necessary to correct the delay in carbonization time due to water evaporation. However, it has been found that the fluctuation range is within 20% when the water content is up to 30%.

When selecting the carbonization time and carbonization temperature using the second correlation, when the atomic ratio H / C is determined, the heat dissipation of the equipment is considered in the change graph of the atomic ratio H / C in FIG. It is desirable to set the carbonization time short. However, as the carbonization time is shortened, it becomes difficult in terms of operation control to obtain the target atomic ratio H / C. For example, when the carbonization temperature is set to 450 ° C. in order to obtain a solid fuel having an atomic ratio of H / C1.4, when the carbonization time is delayed by about 1 minute, the atomic ratio becomes H / C1.5. In order to obtain the target H / C, it is necessary to control the carbonization time within an error range of several tens of seconds, but such operation is substantially difficult.
However, the present inventors have found that the following points are optimum points regarding the setting of the carbonization time and the carbonization temperature at which operation can be substantially controlled.

In the second correlation, when obtaining the target atomic ratio H / C, when the carbonization time at the intersection of the carbonization temperature θ ° C. and the atomic ratio H / C curve is T (θ), the atomic ratio Of the intersections between two adjacent atomic ratio H / C curves that differ by 0.1 point from the H / C curve, the difference in carbonization time closer to the T (θ) (for example, in FIG. When there is a time difference X and Y, X <Y, so X is the reference.)
ΔT (θ) / T (θ) ≧ 0.2
The point of carbonization time becomes the optimal carbonization time.

(Other)
Other examples of organic sludge include human waste sludge and livestock manure sludge, but there is no significant difference from the case of sewage sludge. 6 to 7 and FIG. 13, the data of human waste sludge and livestock manure sludge are indicated by ▲ mark and ● mark, respectively. 6 and 13 show the point where the atomic ratio H / C of the hydrogen content and the carbon content is 1.0, it takes a value almost equivalent to that of sewage sludge. FIG. 7 is also equivalent to the case of sewage sludge.

  The obtained solid fuel is particularly effective when co-firing with coal in a coal-fired power plant, but it can also be applied to boilers that use solid fuel as fuel.

It is a flow sheet of the 1st example of equipment. It is a flow sheet of the 2nd example of equipment. It is a correlation graph of H / C and a combustible content residual rate. It is a correlation graph with H / C and the emitted-heat amount per unit combustible part mass. It is an explanatory diagram relating to the amount of CO _2. It is a 1st correlation diagram of the atomic ratio H / C of the water | moisture content of a sewage sludge, a combustible component, and the hydrogen content in a solid fuel, and a carbon content. It is a correlation graph of H / C and fuel ratio. It is a correlation graph of H / C and calorific value. It is a correlation graph of H / C and a heat_generation | fever rise rate. It is a correlation graph of the amount of oxygen consumption and exothermic rising temperature. 5 is a correlation graph between a temperature increase rate and a heat generation increase temperature. It is a figure which shows the example of a measuring apparatus of the amount of oxygen consumption and a temperature rise rate. It is a 2nd correlation diagram of carbonization time, carbonization temperature, and atomic ratio H / C of the hydrogen content in a solid fuel, and a carbon content.

  DESCRIPTION OF SYMBOLS 1 ... Dehydrated organic sludge, 10 ... Dryer, 14 ... Recombustion furnace, 16 ... 1st heat exchanger, 20 ... Carbonization furnace, 22 ... 1st hot air furnace, 30 ... Measuring apparatus of oxygen consumption and temperature increase rate.

Claims (2)

In the method of producing carbide as solid fuel by carbonizing organic sludge in a carbonization furnace,
The atomic ratio H / C of hydrogen and carbon in the carbide discharged from the carbonization furnace is obtained, and at least one of the carbonization temperature and the carbonization time in the carbonization furnace is set so that the atomic ratio H / C becomes a predetermined control value. While adjusting
The carbide discharged from the carbonization furnace is held for a predetermined time under a predetermined temperature condition while ventilating a gas having a predetermined oxygen concentration, and at least one of the consumed oxygen amount and the temperature rise rate of the carbide is measured. When the measured value exceeds a predetermined safety reference value , the carbon atomization in the carbonization furnace is performed by setting a higher atomic ratio H / C as a new control value so that the measured value is less than the safety reference value. Adjust the temperature or carbonization time,
A method for producing a solid fuel. A carbonization furnace for carbonizing organic sludge;
A carbide extraction device for extracting the carbide discharged from the carbonization furnace;
From the carbide supply port to which all or a part of the carbide extracted by the carbide extraction device is supplied, an air supply port, an air extraction port, a temperature measuring device for measuring the temperature of the carbide, and the air extraction port A measuring device having at least one of oxygen concentration measuring devices for measuring the oxygen concentration of discharged air;
Equipped with a,
In the production of the solid fuel, the atomic ratio H / C of hydrogen and carbon in the carbide discharged from the carbonization furnace is obtained, and the carbonization temperature in the carbonization furnace is set so that the atomic ratio H / C becomes a predetermined control value. And adjusting at least one of the carbonization time,
The measurement device measures at least one of the amount of oxygen consumed and the temperature rise rate of the carbide, and when the measured value exceeds a predetermined safety reference value, a higher atomic value is set so that the measured value is not more than the safety reference value. By adjusting the number ratio H / C as a new control value, the carbonization temperature or carbonization time in the carbonization furnace is adjusted.
Solid fuel production facility characterized in that it is configured .

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