JP2008207160A - Method and device for processing inorganic waste with high water content - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for processing an inorganic waste with high water content which dries the inorganic waste with high water content by using a cement calcination facility so that the inorganic waste with high water content can be effectively used as raw materials, and which is capable of improving operation efficiency with no adverse influence on the operation of the cement calcination facility, and to provide its processing device. <P>SOLUTION: This method for processing the inorganic waste with high water content employs flying ash with high water content as an inorganic waste with high water content to conduct heat exchange between exhaust gas collected from a cyclone 2b of a suspension preheater 2 with a superheated vapor by a heat exchanger 22. The vapor superheated at high temperature after the heat exchange is introduced into a dryer 23 to dry the flying ash with high water content to make it flying ash. The superheated vapor after drying is heat-exchanged again at the heat exchanger 22 and recycled to be used for drying the flying ash with high water content. The obtained dried flying ash is provided to the end part of a rotary kiln 1 of the cement calcination facility as raw materials, so that an organic compound remaining in the dried flying ash is incinerated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and apparatus for treating a high water content inorganic waste, and more specifically, drying a high water content inorganic waste containing an organic compound that requires high temperature heat treatment using a cement firing facility. Thus, the dried inorganic waste can be effectively used as a raw material for cement firing equipment, and the operation of the cement firing equipment is performed despite the use of thermal energy from the cement firing equipment for drying. In addition, the present invention relates to a high moisture content inorganic waste processing method and processing apparatus capable of improving the operational efficiency of cement firing equipment.

Conventionally, it has been studied to reuse incineration ash, incineration fly ash, and the like generated from incineration facilities such as a waste incinerator as raw materials for cement.
Since this incineration ash and incineration fly ash contain a large amount of chlorine and toxic organic compounds of toxic substances, they cannot be used directly as cement raw materials in cement firing facilities, and usually after washing with water, The chlorine-based organic compound remaining in the slurry is incinerated by directly putting it into a kiln bottom of a cement kiln in a slurry state.
For example, in the case of high chlorine-containing incineration fly ash containing dioxins, a suspension obtained by adding water to the incineration fly ash and dissolving a water-soluble chlorine compound contained in the incineration fly ash in water By filtering, the water is separated into a desalted treated product in which dioxins hardly soluble in water remain and a chlorine compound-containing aqueous solution, and the desalted treated product is separated from the rotary kiln of the cement production facility, the lower part of the suspension preheater, or both 800 A treatment method for incinerated fly ash containing dioxins that is introduced into a part at or above ° C and decomposes dioxins has been proposed (Patent Document 1).

By the way, in the processing method mentioned above, since the slurried inorganic waste usually contains 40 to 60% of moisture, when it is directly introduced into the rotary kiln and incinerated, the kiln of the rotary kiln is accompanied by evaporation of moisture. Lower raw material temperature at the bottom, lower sensible heat of raw material heated and decarboxylated in a suspension preheater or calcining furnace, or lower temperature of zone (kiln firing zone) where cement raw material is sintered in clinker As a result, the cement clinker firing ability of the cement firing facility is extremely reduced. Furthermore, since the amount of heat and power consumption per unit clinker at the time of cement clinker firing becomes high, there is a concern that economical operation becomes difficult.
Therefore, in order to reduce the impact of such high moisture content waste on the operation of cement firing equipment, the high moisture content waste is directly dried using the extraction gas from the clinker cooler of the cement firing equipment. The dry waste is effectively used (Patent Document 2).

FIG. 3 is a schematic diagram showing a cement production facility provided with a conventional high water content waste drying treatment apparatus, which is an example of an apparatus for drying high water content waste using exhaust gas from a cement firing facility. .
In the figure, 1 is a rotary kiln, 2 is a suspension preheater, 2a to 2d are cyclones at each stage in the suspension preheater 2, 3 is a calcining furnace, 4 is a clinker cooler, 5 is an electric dust collector, 6 is a suction fan, and 7 is an exhaust. Chimneys, 8a to 8c are cooling air fans for the clinker cooler 4, 9 is a suction fan (IDF) for sucking exhaust gas from the suspension preheater 2, 10 is a secondary air duct for the calciner 3, and 11 is an exhaust duct for the clinker cooler 4. , 12 is an exhaust duct of the suspension preheater 2, and 13 is a raw material supply line to the suspension preheater 2.

Reference numeral 14 denotes a drying treatment apparatus, an extraction duct 15 for extracting a part of the exhaust gas discharged from the clinker cooler 4, a dryer 16 for drying the high water content waste using the extracted exhaust gas, A dust collector 17 that collects dust from exhaust gas containing dry waste, and an exhaust duct 18 and an exhaust introduction fan 19 for reusing the exhaust gas after dust collection as cooling air for the clinker cooler 4 are configured. .
The dry waste obtained by the drying processing apparatus 14 is effectively used as a fuel for cement burning equipment.

By the way, the exhaust gas after drying contains a large amount of odorous components and harmful organochlorine compounds, etc., but this exhaust gas is introduced into the clinker cooler of the cement firing equipment as high-temperature clinker cooling air and cooled. Is used as secondary air for fuel combustion in rotary kilns and calcining furnaces, odor components, organic chlorine compounds and the like are completely burned and decomposed.
Therefore, even if the exhaust gas after drying contains a large amount of odor components, organochlorine compounds, etc., a special heat decomposition means for removing the odor components, organochlorine compounds, etc. in the exhaust gas is not necessary.

In addition, as a drying device for high water content waste that does not depend on the direct drying method using the above-mentioned high temperature gas, a high water content waste drying device using the superheated steam circulation method is attached to the cement firing facility. (Patent Document 3).
This high moisture content waste drying device mixes and stirs the sludge cake made of high moisture content waste and mixes and agitates the dried and dried sludge circulating airflow to adjust the water content. After being crushed, the powder is dried in a drying duct and then collected with a cyclone to obtain dry powder. A certain amount of the obtained dry powder is blown into a rotary kiln of a cement firing facility. It is used as a part of clinker firing fuel.
In this apparatus, the heat medium for drying is exhaust gas (water vapor) generated by drying the sludge cake, the high-temperature part of the cement baking equipment is the exhaust gas heating part that indirectly heats the exhaust gas, and the exhaust gas heating part has the above-mentioned The exhaust gas is introduced to heat and deodorize, a part of the heated and deodorized exhaust gas is circulated to the above-mentioned crusher, and the increased exhaust gas is bleed out of the system, and the remainder of the heated and deodorized exhaust gas is A method of preheating the exhaust gas from the cyclone by exchanging heat with the exhaust gas from the cyclone of the dryer in a heat exchanger.

In addition, as a waste treatment method different from waste with high water content, a method for producing cement using a waste fuel conversion system that treats halogen-containing waste using high-temperature gas in a cement firing facility has been proposed. (Patent Document 4).
In this treatment method, the halogen-containing waste is thermally decomposed by indirect heating using the high-temperature gas extracted from the suspension preheater of the cement firing equipment, and the generated halogen compound is removed, while the combustible gas from which the halogen compound has been removed is removed. And the residue is effectively used as a fuel for cement burning equipment.

In this waste fueling system, a high-temperature gas extracted from a suspension preheater is used as a heat source.
Usually, high-temperature gas in the cement firing equipment includes high-temperature air extracted from the clinker cooler and high-temperature gas extracted from the bottom of the kiln of the rotary kiln. As in this waste fueling system, the suspension preheater is used as a heat source. When the high temperature gas extracted from is used, the influence on the operation of the cement firing facility is relatively small, and the heat source of the cement firing facility can be used effectively.
JP 2001-25731 A JP 63-151650 A JP 2002-273492 A JP 2006-206386 A

By the way, in the method of directly drying high moisture content waste using the bleed gas from the clinker cooler of Patent Document 2 described above, since the exhaust gas after drying contains a large amount of water vapor, it is treated with the clinker cooler. As a result, the water vapor contained in the exhaust gas is introduced into the rotary kiln or calciner, resulting in an increase in the amount of high-temperature gas (gas intensity) required for firing the unit cement clinker. It was.
This increase in the gas basic unit may adversely affect the operation of the cement baking equipment, such as a decrease in the amount of calcined cement clinker and an increase in the calorific value for calcining (caloric unit).
Although the reduction in the amount of calcined cement clinker and the increase in the basic unit of calorific value are less than 20 to 40% of the impact on the operation compared to the case where it is directly input to the kiln bottom of a conventional rotary kiln, The adverse effect is still large, and there is a possibility that the required amount of cement production cannot be obtained with the increase in the treatment of high water content waste.

  Moreover, in the drying method of patent document 3, since the high temperature part of a cement baking equipment main body is utilized as a heating part (heat exchange) which heats the heat medium used for drying, the high temperature part which can be used as a heating part is a suspension. For example, when this high temperature region is selected as a heating unit, the heating medium contains gas or heating raw material inside the cement firing equipment. It will take away a lot of sensible heat. Therefore, there has been a problem that the calorific intensity of clinker firing in the cement firing facility may be deteriorated and the clinker firing ability may be lowered.

  Similarly, the decrease in the amount of calcined cement clinker and the increase in the basic unit of calorie in the cement calcining equipment, the decrease in the amount of calcined clinker is only 40-50% compared to the case where it is directly input to the kiln bottom of the rotary kiln. However, the increase in the calorific value is 80%. That is, in this method, most of the heat source for drying is obtained by depriving the cement calcining facility of useful heat, so that the cement calcining facility is compared with the method using the exhaust gas etc. of other cement calcining facilities. In addition to greatly deteriorating the amount of heat consumed, there is a problem that the required amount of cement production may not be obtained with an increase in the treatment of high water content waste.

Further, in the waste fuel conversion system of Patent Document 4, in order to thermally decompose and separate the halogen-containing waste, it is necessary to heat the halogen-containing waste to a temperature as high as 650 ° C. There has been a problem that the temperature of the high-temperature gas introduced into the indirect heater for thermally decomposing waste must be further increased.
In addition, because of indirect heating, the amount of heat transfer is not sufficient, and the temperature of the exhaust gas after heat exchange is returned to the suspension preheater while maintaining a high temperature. In particular, the exhaust gas in a high temperature state is returned to the exhaust duct of the suspension preheater. In the case of merging, etc., the exhaust gas temperature of the suspension preheater rises, which may cause a reduction in the gas processing capacity of the suction fan (IDF), which in turn leads to a reduction in the production capacity of the cement firing equipment.
Moreover, since the extracted high-temperature gas is discharged from the suspension preheater without reusing its sensible heat, the calorific intensity of cement firing also deteriorates.

  As described above, in the treatment methods and systems disclosed in Patent Documents 2 to 4, when the high water content waste is incinerated using the cement firing facility, the operation of the cement firing facility may be adversely affected. Therefore, the dry waste obtained by drying the high water content waste can be effectively used as a fuel or raw material for cement burning equipment, and even if drying is performed using a heat source taken out from the cement burning equipment. Therefore, there has been a demand for a method for treating high moisture content waste that does not affect the operation of cement burning equipment.

  The present invention has been made in order to solve the above-mentioned problems, and by drying a high moisture content inorganic waste using a cement firing facility, the dried inorganic waste is removed from the cement firing facility. Despite the fact that it can be used effectively as a raw material and the thermal energy from the cement firing equipment is used for drying, there is no risk of adverse effects on the operation of the cement firing equipment, and the operation efficiency of the cement firing equipment. It aims at providing the processing method and processing apparatus of the high water content inorganic type waste which can improve.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have dried a high water content inorganic waste using a heat medium exchanging heat with a high-temperature gas separated from a cement firing facility. This dry inorganic waste is converted into a dry inorganic waste and heat-exchanged again with a high-temperature gas to circulate and reuse the high moisture content inorganic waste. At the same time, the dry inorganic waste is supplied to a cement firing facility. If the harmful components contained in this dry inorganic waste are heated and burned, this dry inorganic waste can be effectively used as a raw material for cement firing equipment, and the operation of cement firing equipment and cement quality As a result, the present invention has been completed.

  That is, the high water content inorganic waste processing method of the present invention is a method of drying a high water content inorganic waste containing an organic compound that requires high-temperature heat treatment, and cement-baking the obtained dry inorganic waste A treatment method for incineration using equipment, wherein the high water content inorganic waste is dried and dried using a heat medium exchanging heat with a high-temperature gas fractionated from the cement firing equipment. A drying treatment step in which the dried heat medium is again heat-exchanged with the high-temperature gas and recycled for drying the high water content inorganic waste, and the dried inorganic waste is used as the cement. And a high-temperature heat treatment step of supplying the high-temperature portion of the baking equipment to a high temperature part of 800 ° C. or higher and performing a high-temperature heat treatment.

In this high water content inorganic waste treatment method, the high water content inorganic waste is dried to a dry inorganic waste using a heat medium exchanging heat with the high temperature gas collected from the cement firing facility. The exhaust gas generated by this drying is only water vapor, and therefore there is no risk of affecting the operation of the cement firing facility even when this exhaust gas is treated by the cement firing facility. Moreover, since the dry inorganic waste is supplied to a high temperature part of 800 ° C. or higher of the cement firing facility and subjected to high temperature heat treatment, harmful organic components contained in the dry inorganic waste are burned and decomposed and remain. Inorganic substances are effectively used as cement raw materials.
Further, since the dried heat medium is again heat-exchanged with the high-temperature gas and recycled for drying the high water content inorganic waste, the heat medium is reused efficiently and effectively, and there is no waste.

  In the method for treating high water content inorganic waste according to the present invention, the high temperature gas is a high temperature gas obtained by extracting from one or more cyclone gas outlets of each stage of the suspension preheater of the cement firing facility. And the heating medium after drying is superheated steam generated by drying the high water content inorganic waste.

In this high moisture content inorganic waste treatment method, the high temperature gas collected from the cement firing facility was extracted from one or more of the cyclone gas outlets of the suspension preheater of the cement firing facility. By using a high temperature gas, the amount of gas passing through the entire cement firing facility is increased, and the cement clinker firing ability of the cement firing facility can be improved.
In addition, the heat medium after drying is superheated steam generated by drying high-water-content inorganic waste, so that the heat medium directly used for the drying process can be minimized and the operation of the cement burning equipment There is no influence on the.

  In the method for treating a high water content inorganic waste according to the present invention, the high-temperature gas is any one of exhaust gas discharged from a suspension preheater of the cement firing facility, or extraction gas extracted from a clinker cooler of the cement firing facility. It is 1 type or 2 types, The said heat medium after the drying is the superheated steam which generate | occur | produced by drying the said high water content inorganic waste.

In this high moisture content inorganic waste treatment method, the high temperature gas fractionated from the cement firing facility is exhausted from the suspension preheater of the cement firing facility, and the extracted gas is extracted from the clinker cooler of the cement firing facility. By using any one or two of them, there is no possibility of adversely affecting the operation of the cement firing facility by using the high temperature gas.
In addition, the heating medium after drying is superheated steam generated by drying high-water-content inorganic waste, so that the amount of gas used for the drying process can be minimized, and the operation of cement firing equipment can be achieved. There is no influence.

  The method for treating a high water content inorganic waste according to the present invention comprises extracting a part of the superheated steam, heating the extracted superheated steam to a high temperature to decompose an organic compound contained in the superheated steam, The treated superheated steam is introduced into the cement firing facility.

  In this high moisture content inorganic waste processing method, the extracted superheated steam is heated to a high temperature to decompose the organic compound contained therein, and the decomposed superheated steam is introduced into a cement firing facility. For example, when it is introduced into a suspension preheater exhaust gas system, the influence of the introduction on the operation of the cement firing equipment can be completely eliminated. As a result, the improvement of the baking ability appears remarkably.

The high moisture content inorganic waste processing method of the present invention is characterized in that a part of the superheated steam is directly introduced into a high-temperature part of the cement firing facility at 800 ° C. or higher.
In this high moisture content inorganic waste processing method, by introducing a part of superheated steam directly into the high temperature part of the cement firing facility at 800 ° C or higher, the amount of superheated steam introduced is only the amount generated by drying. Therefore, the influence on the operation of the cement firing equipment is extremely small, and the influence can be sufficiently canceled out by improving the cement clinker firing ability by the extraction of the outlet of each stage cyclone gas.

The high water content inorganic waste processing method of the present invention is such that the high water content inorganic waste has a water content of 30% or more obtained by washing the incineration ash and / or incineration fly ash with water and subjecting it to a desalting treatment. It is characterized by high water content waste.
In this high water content inorganic waste treatment method, incinerated ash containing a large amount of chlorine and chlorinated organic compounds and incinerated fly ash after washing with high water content waste are dried, and then the cement firing device is used at 800 ° C. By introducing it into the above high-temperature section and processing it, the chlorinated organic compounds contained in the incineration ash and incineration fly ash can be pyrolyzed without affecting the operation of the cement baking equipment. In addition, the remaining inorganic components can be used as raw materials for cement burning equipment.

  The high moisture content inorganic waste treatment apparatus of the present invention is a high moisture content inorganic waste containing an organic compound that requires high temperature heat treatment, and the resulting dry inorganic waste is subjected to cement firing equipment. An apparatus for treating high water content inorganic waste to be incinerated using heat exchanging means for exchanging heat between a high-temperature gas and a heat medium separated from the cement burning equipment, and the heat exchanged heat Drying means for drying the high water content inorganic waste using a medium to form dry inorganic waste, and circulation for circulating the dried heat medium between the heat exchange means and the drying treatment means And a supply line for supplying the dry inorganic waste to the high temperature part of the cement firing facility at 800 ° C. or higher.

  In this high water content inorganic waste processing apparatus, heat exchange is performed between the high-temperature gas collected from the cement firing facility and the heat medium by the heat exchange means, and this heat exchange heat medium is obtained by the drying treatment means. Is used to dry high-water content inorganic waste to dry inorganic waste, and this dry inorganic waste is supplied to a cement firing facility through a supply line, and the contained organic compound is heated and thermally decomposed. As a result, the organic compound contained in the dry inorganic waste is completely pyrolyzed and rendered harmless, and there is no possibility that the pyrolysis of the organic compound will affect the operation of the cement calcination facility. Ability improves.

And the dry inorganic waste obtained by using effectively the sensible heat which the waste gas discharged | emitted from a cement baking apparatus uses effectively is used as a raw material of cement baking equipment.
In addition, it is possible to efficiently and effectively reuse the heat medium by circulating the heat medium after drying again with high-temperature gas and circulating it for drying high-water content inorganic waste through the circulation line. It is.

The high moisture content inorganic waste processing apparatus of the present invention comprises a heat treatment means for extracting a part of the superheated steam generated by the drying treatment means and further subjecting the extracted superheated steam to a heat treatment. It is characterized by that.
In this high water content inorganic waste processing apparatus, a part of the superheated steam generated by the drying processing means is extracted, and the heat processing means heats the extracted superheated steam. As a result, it is possible to supply and process high-temperature water vapor in which organic components are decomposed to a suspension preheater exhaust gas system of a cement firing facility, and no influence is exerted on the operation of the cement firing facility.

The high moisture content inorganic waste processing apparatus of the present invention extracts a part of the superheated steam generated in the drying processing means, and the extracted superheated steam is applied to a high temperature part of the cement firing facility of 800 ° C. or higher. It is characterized by comprising a heat treatment line for direct introduction and heat treatment.
In this high water content inorganic waste processing apparatus, a part of the superheated steam generated in the drying processing means is extracted by the heat processing line, and is directly introduced into the high temperature part of 800 ° C. or higher of the cement burning equipment and extracted. By performing the heat treatment of the steam, it is possible to efficiently treat the high water content inorganic waste despite the simple heat treatment of the superheated steam.

The high water content organic waste treatment apparatus of the present invention is the heat exchange means using as a high temperature gas the extracted gas collected from any one or more of the cyclone gas outlets of each stage of the suspension preheater of the cement firing facility. It is characterized in that it is provided with a line to be introduced.
In this high moisture content inorganic waste processing apparatus, the hot gas is fractionated from any one or more of the cyclone gas outlets of each stage of the suspension preheater of the cement firing equipment by a line introduced into the heat exchange means of the high temperature gas. As a result, the ventilation capacity of the cement firing facility is improved, so there is no risk of deterioration of the cement clinker firing capacity due to the operation of this high water content inorganic waste treatment device, and the high moisture content efficiently. Rate inorganic waste can be treated.

  The high moisture content inorganic waste treatment apparatus of the present invention is a line for introducing exhaust gas from a suspension preheater of the cement firing equipment into the heat exchange means as a high temperature gas, and an extraction gas extracted from a clinker cooler of the cement firing equipment. One or both of the lines introduced into the heat exchange means as a high-temperature gas are provided.

  In this high water content inorganic waste processing apparatus, a line for introducing exhaust gas separated from the suspension preheater to the heat exchange means as a high temperature gas, a line for introducing the extraction gas extracted from the clinker cooler to the heat exchange means as a high temperature gas By providing either or both of the above, it becomes possible to use the exhaust gas separated from the suspension preheater or the extraction gas extracted from the clinker cooler as a high-temperature gas, and the high-temperature gas after heat exchange is again cemented By using it for drying the raw material, it can be used efficiently and effectively, and the influence on the operation of the cement firing facility can be eliminated.

According to the method for treating high water content inorganic waste of the present invention, high water content inorganic waste containing an organic compound that requires high temperature heat treatment is heat exchanged with a high temperature gas fractionated from a cement firing facility. Since it is dried using a heat medium to produce a dry inorganic waste, there is no risk of affecting the operation of the cement firing equipment, and the resulting dry inorganic waste can be used effectively as a raw material for the cement firing equipment. .
Further, since the dried heat medium is again heat-exchanged with the high-temperature gas and recycled for drying the high water content inorganic waste, the heat medium can be reused efficiently and effectively.

According to the high moisture content inorganic waste processing apparatus of the present invention, heat exchange means for exchanging heat between the high temperature gas collected from the cement firing facility and the heat medium, and the heat exchange heat medium are used. Drying treatment means for drying the high water content inorganic waste to dry inorganic waste, a circulation line for circulating the dried heat medium between the heat exchange means and the drying treatment means, And a supply line that supplies dry inorganic waste to a high temperature part of 800 ° C. or more of the cement firing facility, so that the sensible heat of the exhaust gas discharged from the cement firing facility can be used effectively. There is no risk of affecting the operation of the firing facility, and the firing capacity of the cement clinker of the cement firing facility can be improved.
Further, since the dried heat medium is again heat-exchanged with the high-temperature gas and recycled for drying the high water content inorganic waste, the heat medium can be reused efficiently and effectively.

BEST MODE FOR CARRYING OUT THE INVENTION The best mode of a high moisture content inorganic waste processing method and processing apparatus of the present invention will be described with reference to the drawings.
The present embodiment is specifically described for better understanding of the gist of the invention, and does not limit the invention unless otherwise specified.

“First Embodiment”
FIG. 1 is a schematic view showing a cement firing facility provided with a high moisture content fly ash drying treatment apparatus (high moisture content inorganic waste treatment apparatus) according to a first embodiment of the present invention. Incinerated fly ash is washed with water to remove the chlorine component contained in it, and the high moisture content fly ash is used as inorganic waste. This is an example of a processing apparatus that dries dry fly ash, incinerates the chlorinated organic compound remaining in the dry fly ash using a cement firing facility, and effectively uses the remaining inorganic material as a raw material for the cement firing facility. .

The incineration fly ash usually contains about 10 to 20% of chlorine in addition to inorganic components, and further contains harmful substances such as dioxins and precursor compounds thereof. Therefore, when this incinerated fly ash is treated in the cement firing facility, the chlorine component that may adversely affect the operation of the cement firing facility is previously removed by washing with water.
However, the fly ash washed with water contains about 40 to 60% of water after dehydration with a dehydrator, and further dioxins and precursor compounds remain. In order to treat with the equipment, this fly ash must be introduced into the high temperature part of the cement firing equipment and incinerated with harmful substances such as dioxins to make them harmless. In this case, since fly ash has a high water content, evaporation of water contained therein has a great influence on the operation of the cement firing facility.

  The processing apparatus of this embodiment is made in view of such a situation, and when processing high moisture content fly ash using a cement baking facility, it is processed by a method that does not affect the operation of the cement baking facility. It corresponds to the drying system of high moisture content fly ash which is a part of the equipment.

  In the figure, 21 is a drying apparatus for high moisture content fly ash, a heat exchanger for exchanging heat between exhaust gas (high temperature gas) and steam (heat medium) collected from the suspension preheater 2 of the cement firing facility. (Heat exchange means) 22, a dryer (drying treatment means) 23 that dries high-water-content fly ash using the heat-exchanged superheated steam (heat medium) to dry ash, and organics contained in the superheated steam A heater (heat treatment means) 24 for thermally decomposing compounds, a hopper 25 for storing dry fly ash, a hot gas extraction duct (line) 26, an exhaust duct (line) 27, and a superheated steam line (circulation line) 28, superheated steam line (bleeding line) 29, high moisture content fly ash supply line 30 for supplying high moisture content fly ash to the dryer 23, and supply line for supplying dry fly ash to the kiln bottom of the rotary kiln 1 With 31 It is configured.

In order to dry and incinerate the high water content fly ash by the high water content fly ash drying treatment device 21, the high-temperature gas and superheated steam line separated from the gas outlet of the second-stage cyclone 2 b of the suspension preheater 2 are used. Steam (heat medium) circulating through 28 is introduced into the heat exchanger 22, and the steam is heated by this high-temperature gas to form superheated steam (heat medium).
This superheated steam is introduced into the dryer 23 via the superheated steam line 28, and the high water content fly ash introduced by the high water content fly ash supply line 30 is dried in the dryer 23, and the dry fly Ashes. The dry fly ash is once stored in the hopper 25 and then supplied as a raw material of cement to the kiln bottom of the rotary kiln 1 through the supply line 31, and harmful substances such as chlorinated organic compounds remaining in the dry fly ash are present. Incinerated.

  This high moisture content fly ash drying apparatus 21 uses a high-temperature gas extracted from the outlet gas of the second-stage cyclone 2b from the uppermost cyclone 2a of the suspension preheater 2 to perform a drying method using heat-exchanged steam, That is, by adopting a drying method based on a superheated steam circulation method, the high-temperature gas in the cement firing facility is effectively used and the efficiency of the cement firing facility is improved.

Here, selection of the extraction position in the cyclones 2a to 2d will be described.
For example, when the exhaust gas is extracted from the outlet of the second-stage cyclone 2b, the effective utilization of the exhaust gas at the outlet of the cyclone 2b is low. Rather, the exhaust gas temperature of the suspension preheater 2 is lowered by the extraction, and the exhaust gas is extracted. Compensates for heat loss and eliminates the increase in heat intensity.
At the same time, the temperature of the extracted exhaust gas is lowered by heat exchange in the dryer 23, and the ventilation capacity of the suction fan (IDF) 9 that sucks the gas merged with the exhaust gas from the suspension preheater 2 is increased.
Thereby, the clinker baking ability of a cement baking equipment will be improved. Due to the improvement of the clinker firing ability, the caloric intensity may be improved.

The improvement effect of the clinker firing capacity increases as the extraction position of the exhaust gas becomes the lower cyclone, but in the lower cyclone, the amount of heat loss due to the extraction gas increases, and the effect on the calorific value increases gradually. The rate of increase in the clinker firing capacity of the firing equipment will decrease. Therefore, the cyclone to be extracted is most preferably the second-stage cyclone 2b, and the third-stage cyclone 2c is the next most preferable.
Note that the above-described effect can be obtained even if exhaust gas from the outlet of the uppermost cyclone 2a is used. In this case, it is necessary that the extraction device for extracting the exhaust gas from the cyclone 2a does not increase the ventilation resistance of the suspension preheater 2 to the exhaust gas. As a countermeasure, heat is applied to the surface portion of the exhaust duct 12 of the suspension preheater 2. There is a method of attaching an exchange part.

The temperature of the hot gas extracted from the gas outlet of the second-stage cyclone 2b is usually in the range of 550 to 650 ° C. This high-temperature gas is obtained by extracting from a position where the powder raw material introduced by the raw material supply line 13 for cement powder raw material is not mixed. The amount of high-temperature gas to be extracted is about 40 to 60% by weight of the moisture content of the high moisture content fly ash to be dried, so that the moisture contained in the high moisture content fly ash is evaporated to form superheated steam. An amount sufficient for the required amount of heat is required. That is, it is necessary to extract a gas amount of usually ³ to 6 Nm ³ per kg of high water content fly ash.

Further, when the concentration of dust in the exhaust gas to be extracted is high, or when a large amount of volatile components causing anzatz to the subsequent heat exchanger 22 is contained, a dust collector such as a cyclone is provided in the high temperature gas extraction duct 26. It is preferable to attach.
Further, a dust collector such as a cyclone is attached to the exhaust duct 27, and dust in the exhaust gas after being cooled by the heat exchanger 22 is collected by the dust collector so that it is volatilized in the subsequent suction fan (IDF) 9 and the like. You may prevent that a component adheres.

The high-temperature gas extracted from the suspension preheater 2 is further heated by the heat exchanger 22 to 130-200 ° C. overheated steam discharged from the dryer 23, which is a circulating drying heat medium, to 300-400 ° C. To do.
The temperature of the hot gas is reduced to 300 to 350 ° C. by this heat exchange, and merges with the exhaust gas from the suspension preheater 2 in the exhaust duct 12.
In order to increase the amount of heat exchange in the heat exchanger 22, the heat transfer area of the heat exchanger 22 may be increased. However, when exhaust gas after heat exchange is used for drying cement raw material, When used as a heat source for a boiler of a power generator, it is not always necessary to increase the heat transfer area and greatly reduce the gas temperature after heat exchange. Considering these conditions, as the structure of the heat exchanger 22, a multi-tube heat exchanger, a plate heat exchanger, or the like is preferable.

The high temperature gas whose temperature has been reduced by heat exchange in the heat exchanger 22 is introduced into the exhaust duct 12 of the suspension preheater 2 and merges with the exhaust gas from the suspension preheater 2.
Here, for example, when the heat exchange in the heat exchanger 22 is not sufficient and the exhaust gas temperature after the heat exchange is higher than the exhaust gas temperature of the suspension preheater 2 by 150 ° C. or more, the degree of increase in the exhaust gas temperature after joining As the suction gas temperature of the suction fan (IDF) 9 increases, the air blowing capacity decreases, so that there is no room for improvement in the firing capacity of the cement clinker 1 of the cement firing facility. There is a risk that the loss of sensible heat will increase and the basic unit of heat will deteriorate.

The upper limit value of the high temperature gas temperature after the heat exchange is set to 150 degrees higher than the exhaust gas temperature of the suspension preheater 2 by ensuring a predetermined area as the heat transfer area of the heat exchanger 22. It is preferable to set the temperature to a higher temperature. More preferably, the temperature is 100 ° C. higher. If it is a high-temperature gas cooled to a temperature below this upper limit value, the gas temperature after merging with the suspension preheater exhaust gas will decrease.
For example, when the exhaust gas of the suspension preheater 2 whose temperature has been reduced by 20 to 30 ° C. by extracting about 20% of the high temperature gas and the high temperature gas after heat exchange are merged, the temperature after the merge is not extracted. Therefore, the suction force of the suction fan (IDF) 9 can be further increased.

This means that the temperature of the hot gas extracted from the gas outlet portion of the second-stage cyclone 2b (550 to 650 ° C) is 100 to 150 ° C higher than the exhaust gas temperature (about 350 ° C) of the suspension preheater 2 by heat exchange. If the temperature is lowered to a temperature (upper limit 450 to 500 ° C.) or less, the gas temperature after merging will be lower than that before extraction. Further, by extracting the high-temperature gas, the pressure loss due to gas passing through the uppermost cyclone 2a is also reduced, so that the suction force of the suction fan (IDF) 9 is further increased and the cement clinker firing ability is improved. It becomes possible.
Considering these points, even if the performance of the heat exchanger is not high, the high-temperature gas extracted to a predetermined temperature can be easily reduced, so that the high moisture content fly ash drying treatment apparatus can be reduced in size and simplified. Can be

  On the other hand, the high water content fly ash supplied to the dryer 23 by the high water content fly ash supply line 30 is brought to the boiling point of water or the vicinity thereof by superheated steam circulating between the dryer 23 and the superheated steam line 28. Until the water content is reduced to dry ash. Here, in order to increase the dryness of the dry fly ash, it is necessary to increase the temperature until the dryness of the high moisture content fly ash becomes the dry rate dry state, but usually the high moisture content fly ash during heating Since the dry fly ash having a water content of about 5 to 10% is easily obtained in the range of the constant rate dry state while maintaining the temperature of about 100 ° C., the superheated steam at an excessively high temperature is used as a heating medium of the drying apparatus. Not necessary.

  Therefore, the feature of this embodiment is that it is not necessary to make the temperature of the heat medium of the drying device excessively high, and the temperature of the high-temperature gas after the heat exchange in the heat exchanger 22 can be reduced. It is in. In other words, since it is easy to lower the temperature after heat exchange of the high-temperature gas than the exhaust gas temperature of the suspension preheater 2, the exhaust gas of the suspension preheater 2 and the temperature after the merging of this gas are reduced, and the suction fan ( IDF) 9 gas flow rate can be increased.

As the dryer 23, an air dryer, a fluidized bed dryer, or the like can be used. However, a material transfer type in which the amount of dust contained in the exhaust gas after drying is small and the degree of drying can be controlled relatively easily. A hot air type multi-stage dryer is preferred.
The dry fly ash thus obtained is once stored in the hopper 25, then pneumatically transported through the supply line 31 and charged as a raw material into the kiln bottom of the rotary kiln 1, and the chlorine remaining in the dry fly ash Hazardous substances such as organic compounds are incinerated.

  On the other hand, the superheated steam evaporated from the high water content fly ash in the dryer 23 is joined to the circulating superheated steam, and then a part of the superheated steam is sent to the heater 24 via the superheated steam line 29. Hazardous substances such as chlorinated organic compounds remaining in the tank are heated and decomposed, and then rejoin the exhaust gas line 12 of the suspension preheater 2 to be used for drying cement raw materials.

As described above, according to the high moisture content fly ash drying treatment method of the present embodiment, there is no risk of affecting the operation of the cement firing equipment, and the obtained dry fly ash is effective as a raw material for the cement firing equipment. Can be used.
Moreover, since the superheated steam after drying is again heat-exchanged with the exhaust gas and recycled for drying the high water content fly ash, the superheated steam can be reused efficiently and effectively.

According to the high moisture content fly ash drying apparatus of the present embodiment, the sensible heat of the high-temperature gas extracted from the suspension preheater 2 of the cement firing facility can be used effectively, which affects the operation of the cement firing facility. This can improve the firing ability of the cement clinker of the cement firing equipment.
Further, since the superheated steam after drying is again heat-exchanged with the high-temperature exhaust gas and recycled for drying the high water content fly ash, the superheated steam can be reused efficiently and effectively.

  Instead of sending a part of the superheated steam to the heater 24, the superheated steam is sent from the gas outlet of the lowermost cyclone 2d of the suspension preheater 2 to the upper cyclone 2c of the lowermost cyclone 2d, or the clinker cooler 4 The cement of this embodiment can be directly introduced into the cooling air inlet and thermally decomposed harmful substances such as chlorinated organic compounds via a high temperature part of 800 ° C. or higher in the cement firing facility. It is possible to maintain a state that does not adversely affect the operation of the firing facility.

  Further, instead of sending a part of the heated steam to the heater 24, the superheated steam may be recovered as moisture by cooling it with a condenser or the like, and the recovered moisture decomposes organic compounds contained therein. It is good also as performing the waste water treatment to use and using again in a cement manufacturing facility.

“Second Embodiment”
FIG. 2 is a schematic view showing a cement firing facility provided with a high moisture content fly ash drying apparatus according to the second embodiment of the present invention. The difference from the high moisture content fly ash drying treatment apparatus 21 of the embodiment is that the high temperature gas extraction duct 26 and the exhaust duct 27 are replaced with a high temperature gas extraction line 42 and a high temperature gas exhaust line 43, and the drying of the dryer 23 is performed. The high-temperature gas used in the above is a high-temperature exhaust gas branched from the exhaust duct 12 on the downstream side of the suction fan (IDF) 9 of the suspension preheater 2.

In this high moisture content fly ash drying treatment apparatus 41, the high-temperature exhaust gas serving as the heat source for drying is branched from the exhaust duct 12 of the suspension preheater 2 and sent to the heat exchanger 22 through the high-temperature gas extraction line 42. The exhaust gas, chlorine gas was volatilized at high temperature portion of the cement burning facility, SO _x and other volatile components not included little and since the content of the dust is relatively small, sent to the heat exchanger 22 There is no need to remove these components in advance before being applied.
The exhaust gas from the suspension preheater 2 is introduced into the heat exchanger 22 at a temperature of about 350 to 400 ° C., is cooled to about 200 ° C. after heat exchange with the superheated steam, and then is chlorinated in the heater 24. The exhaust gas from the suspension preheater 2 is joined again in the exhaust duct 12 of the suspension preheater 2 in the same manner as a part of the superheated steam from which harmful substances such as organic compounds are thermally decomposed and removed.

  According to the high moisture content fly ash drying treatment apparatus 41, the high-temperature gas used for drying the dryer 23 is a high-temperature exhaust gas branched from the exhaust duct 12 on the downstream side of the suction fan (IDF) 9 of the suspension preheater 2. Therefore, it can introduce | transduce into the same position, after heat-exchanging and temperature falling. In addition, since the superheated steam generated by the drying of the high water content fly ash is heat-treated and then introduced into the exhaust duct 12, there is no effect on the gas ventilation in the cement firing facility. High moisture content fly ash can be treated without affecting the operation of the firing facility.

It is a schematic diagram which shows the cement baking equipment which attached the drying processing apparatus of the high moisture content fly ash of the 1st Embodiment of this invention. It is a schematic diagram which shows the cement baking equipment which attached the drying processing apparatus of the high moisture content fly ash of the 2nd Embodiment of this invention. It is a schematic diagram which shows the cement manufacturing equipment which attached the drying processing apparatus of the conventional high moisture content waste.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotary kiln 2 Suspension preheater 2a-2d Cyclone 3 Calciner 4 Clinker cooler 5 Electric dust collector 6 Suction fan 7 Exhaust chimney 8a-8c Cooling air fan 9 Suction fan (IDF)
DESCRIPTION OF SYMBOLS 10 Secondary air duct 11 Exhaust duct 12 Exhaust duct 13 Raw material supply line 21 Drying apparatus of high moisture content fly ash 22 Heat exchanger 23 Dryer 24 Heater 25 Hopper 26 High temperature gas extraction duct 27 Exhaust duct 28 Superheated steam line 29 Superheated steam line 30 High moisture content fly ash supply line 31 Supply line 41 Drying device for high moisture content fly ash 42 High temperature gas extraction line 43 High temperature gas exhaust line

Claims (11)

A treatment method for drying a high water content inorganic waste containing an organic compound that requires high-temperature heat treatment, and subjecting the resulting dry inorganic waste to incineration using a cement firing facility,
The high water content inorganic waste is dried using a heat medium exchanging heat with the high temperature gas collected from the cement baking equipment to obtain a dry inorganic waste, and the dried heat medium is again the high temperature. A drying treatment step for heat exchange with gas to circulate and use for drying the high water content inorganic waste;
A high-temperature heat treatment step of supplying the dry inorganic waste to a high-temperature portion of 800 ° C. or more of the cement firing facility and performing a high-temperature heat treatment;
A process for treating inorganic waste with high water content, comprising: The high-temperature gas is a high-temperature gas obtained by extracting from any one or more of the cyclone gas outlets of each stage of the suspension preheater of the cement firing facility,
The method for treating high water content inorganic waste according to claim 1, wherein the heat medium after drying is superheated steam generated by drying the high water content inorganic waste. The high-temperature gas is any one or two of exhaust gas discharged from a suspension preheater of the cement firing facility, and extraction gas extracted from a clinker cooler of the cement firing facility,
The method for treating high water content inorganic waste according to claim 1, wherein the heat medium after drying is superheated steam generated by drying the high water content inorganic waste.   Extracting a part of the superheated steam, heating the extracted superheated steam to a high temperature to decompose organic compounds contained in the superheated steam, and introducing the decomposed superheated steam into the cement firing facility The processing method of the high water content inorganic waste of Claim 2 or 3 characterized by these.   The method for treating a high water content inorganic waste according to claim 2, wherein a part of the superheated steam is directly introduced into a high temperature part of 800 ° C or higher of the cement firing facility.   The high water content inorganic waste is a high water content waste having a water content of 30% or more obtained by washing incineration ash and / or incineration fly ash with water and subjecting to desalination. The processing method of the high water content inorganic waste of any one of thru | or 5. High moisture content inorganic waste treatment equipment that dries high moisture content inorganic waste containing organic compounds that require high temperature heat treatment, and incinerate the resulting dry inorganic waste using cement firing equipment Because
Heat exchange means for exchanging heat between the high-temperature gas collected from the cement firing facility and the heat medium, and drying the high water content inorganic waste using the heat exchanged heat medium to dry inorganic waste A drying treatment means to be a product, a circulation line for circulating the dried heat medium between the heat exchange means and the drying treatment means, and the dried inorganic waste at a temperature of 800 ° C. or more of the cement baking equipment. A high water content inorganic waste processing apparatus comprising a supply line for supplying to a high temperature section.   The high water content inorganic system according to claim 7, further comprising a heat treatment means for extracting a part of the superheated steam generated by the drying treatment means and further subjecting the extracted superheated steam to a heat treatment. Waste treatment equipment.   A part of the superheated steam generated by the drying processing means is extracted, and the extracted superheated steam is directly introduced into a high-temperature part of 800 ° C. or more of the cement baking equipment to perform a heat treatment line. The apparatus for treating a high water content inorganic waste product according to claim 7.   2. A line for introducing, as a high-temperature gas, an extraction gas collected from any one or more of the cyclone gas outlets of each stage of the suspension preheater of the cement firing equipment, into the heat exchange means. The processing apparatus of the high water content inorganic waste of 7 or 8 or 9.   Either a line that introduces the exhaust gas of the suspension preheater of the cement firing equipment into the heat exchange means as a high temperature gas, or a line that introduces the extraction gas extracted from the clinker cooler of the cement firing equipment into the heat exchange means as a high temperature gas. One or both of them are provided, The processing apparatus of the high water content inorganic waste of Claim 7 or 8 characterized by the above-mentioned.

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