JP2005180881A - Waste treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waste treatment device with high treatment efficiency and high combustion temperature capable of melting also a non-inflammable matter to reduce the incineration residue while remarkably reducing harmful substances in exhaust gas. <P>SOLUTION: This treatment device for waste or the like comprises a preheating chamber 1 for preheating an object to be treated and a high-temperature chamber 2 for burning/melting the preheated object. A burner 10 for burning a mixed gas of hydrogen and oxygen obtained by electrolysis of water and an emulsified fuel is set in the high-temperature chamber, and the preheating of the object within the preheating chamber is performed with a combustion exhaust gas generated in the high-temperature chamber. This device comprises a mechanism for circulating and using the combustion exhaust gas generated in the high-temperature chamber as a part of combustion air for the emulsified fuel, and an electrolytic device of water for generating the mixed gas of hydrogen and oxygen and a device for emulsifying the fuel are desirably attached thereto. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an apparatus for efficiently incinerating various types of wastes and melting and detoxifying non-combustible materials such as combustion residues and metals and glass mixed in the wastes. According to this apparatus, waste contaminated with harmful substances such as PCB can be easily detoxified, and NOx and other harmful substances in the combustion exhaust gas can be significantly reduced.

  In recent years, the treatment of domestic waste such as industrial waste and garbage has become a big problem. Among them, the waste contaminated with PCB remains in the residue after the treatment if the treatment method is not appropriate, which causes secondary contamination. In the case of incineration, harmful substances such as NOx and dioxin may be contained in the exhaust gas, and reducing them is also an important issue.

  Combustible waste is generally incinerated, but in that case, a new problem arises of disposal of residue (incinerated ash) after incineration. Since it is difficult to secure a landfill if there is a large amount of residue, it is desirable to reduce the amount of residue generated and make it available for effective use. Furthermore, if it is intended to reduce the cost of collecting and transporting waste, it is necessary to place the treatment equipment close to the source of waste. Therefore, a small and efficient facility is desired.

  As existing waste incineration facilities, there are many types in which waste is put into a furnace equipped with a burner for burning heavy oil and the like and burned. In such a furnace, it is necessary to separate a flammable substance and a nonflammable material such as metal or glass in advance. Since it is difficult to complete the separation, non-flammable materials are also put into the lively furnace, and these are mixed into the combustion residue. Under such circumstances, not only does the amount of combustion residue increase, but it also hinders effective utilization of the residue.

  Also, in general incinerators, harmful substances such as dioxins and NOx may be contained in exhaust gas, and in order to prevent these occurrences, considerations such as adjusting the combustion temperature and limiting the type of waste to be introduced are necessary. It is.

  The object of the present invention is to reduce the amount of incineration residue by increasing the treatment efficiency and increasing the combustion temperature to melt non-combustibles, and with extremely little harmful substances in the exhaust gas. It is in providing a processing apparatus.

  In the present invention, if an emulsified fuel is blown into a flame obtained by burning a mixed gas of hydrogen and oxygen obtained by electrolysis of water, a high-temperature flame can be obtained very efficiently, and combustion including non-flammable substances It was made based on the knowledge that the residue can be melted.

  The waste processing apparatus of the present invention is the following processing apparatus (1).

  (1) A waste treatment apparatus including a preheating chamber for a workpiece and a high temperature chamber for burning and melting the preheated workpiece. The high temperature chamber is obtained by electrolysis of water. A waste which is provided with a burner for burning a mixed gas of hydrogen and oxygen and an emulsified fuel, and the preheating of the object to be processed in the preheating chamber is performed by combustion exhaust gas generated in the high temperature chamber Etc. Processing equipment.

  The processing apparatus preferably includes a mechanism that circulates the combustion exhaust gas generated in the high temperature chamber and uses it as part of the combustion air of the emulsified fuel. Moreover, it is desirable that the above apparatus is additionally provided with a water electrolysis apparatus for generating a mixed gas of hydrogen and oxygen supplied to the burner and an apparatus for emulsifying the fuel.

  The above burner burns a mixed gas of hydrogen and oxygen obtained by electrolyzing water (hereinafter referred to as “electrolytic hydrogen / oxygen gas”), and the liquid fuel and water are the main components in the flame. It is a burner that blows and burns emulsion fuel.

Best Mode for Carrying Out the Invention

  Hereinafter, the device of the present invention will be described with reference to specific examples shown in the drawings.

  1 and 2 are diagrams showing an example of the device of the present invention. 1 is a vertical sectional view of the center of the apparatus, and FIG. 2 is a horizontal sectional view taken along line AA of FIG.

  As shown in FIG. 1, this apparatus has a preheating chamber 1 and a high temperature chamber 2. At one end of the apparatus (the right end in the figure), there is a hopper 3 for charging an object to be processed (waste). The object to be processed dropped from the hopper 3 is pushed by the pusher 4 and passes through the preheating chamber 1. It is sent into the high greenhouse 2.

  In the illustrated apparatus, there is a passage 5 for the exhaust gas generated in the high temperature chamber 2 above the preheating chamber 1, and the exhaust gas rising from the riser pipe 5-1 is guided to the burner 10. There is a blower 5-2 at the right end of the passage 5, which helps to circulate the combustion exhaust gas left from the ascending pipe 5-1 by blowing in outside air, and to supply air to the combustion exhaust gas. Used for.

  Part of the exhaust gas generated in the high greenhouse 2 reaches the secondary combustion device 8 through the passage 7. Here, the combustible gas in the exhaust gas is burned. The combustion exhaust gas is discharged into the atmosphere after being dust-removed by a cyclone 9 and, if necessary, a scrubber or the like. As will be described later, this exhaust gas contains almost no harmful substances.

  The secondary combustion device 8 may be provided with, for example, a steam generation pipe or the like, and the combustion heat may be recovered in the form of steam. Also, preheating of the combustion air blown into the burner may be performed here.

  Most of the exhaust gas generated in the high greenhouse 2 is sent from the passage 5 to the burner 10 as described above, but a small part also flows to the right side from the preheating chamber 1 through the workpiece charging passage 6. This gas heats the object to be moved to the left in the preheating chamber, and is released into the atmosphere through the hopper 3, but the amount thereof is very small.

  A burner 10 is installed in the high greenhouse 2. This burner 10 is of a type that enables the special combustion described below. The combustible material in the object to be processed is completely burned in the high temperature chamber 2. In addition, non-combustible materials such as combustion residues (ash) and metals, glass, ceramics and the like mixed in the object to be processed are melted to form a slag.

  FIG. 3 is a conceptual diagram for explaining the combustion state of the burner. A burner 10 (enclosed by a broken line) is supplied with a mixed gas of hydrogen and oxygen from a hydrogen / oxygen generator 11 and with emulsion fuel from a tank 12. The hydrogen / oxygen generator is an apparatus that generates water by electrolyzing water. The hydrogen / oxygen generator is preferably provided in the apparatus of the present invention, but electrolytic hydrogen / oxygen produced in another place may be accommodated in a tank and used.

  4A and 4B are diagrams showing the structure of the burner 10, in which FIG. 4A is a cross-sectional view, and FIG. 4B is a cross-sectional view of a fuel supply cylinder (A-A cross-sectional view in FIG. 4A). As shown in FIG. 1 (a), the burner 10 includes a fuel supply cylinder 11 at the center of the refractory 12. There is a combustion chamber 14 surrounded by a refractory 13 at the front end side of the fuel supply cylinder. A number of suction holes 15 for combustion air are arranged in the refractory 12 in the circumferential direction.

  As shown in FIG. 4B, the fuel supply cylinder 11 is a refractory pipe, and a number of nozzles 11-1 for blowing out electrolytic hydrogen / oxygen gas are arranged in the circumferential direction on the pipe wall. In the center, there is a nozzle 11-2 for blowing emulsion fuel. Note that the nozzle 11-1 is slightly inclined toward the central axis of the fuel supply cylinder so that the flame is concentrated at one point as shown in FIG.

  If the burner having the above structure is first ignited by injecting electrolytic hydrogen / oxygen gas, the flame temperature becomes as high as 2000 ° C to 3500 ° C. Use of electrolytic hydrogen / oxygen gas has the following advantages.

The electrolytic hydrogen / oxygen gas is a mixed gas of hydrogen and oxygen and has a composition of 2H + O. In addition, about 2 m ³ of electrolytic hydrogen / oxygen gas is obtained by electrolysis of 1 liter of water. Air is not required to burn the electrolytic hydrogen / oxygen gas, and only water (H ₂ O) is generated by combustion. And the calorific value per unit volume is large, and the maximum temperature of the flame reaches 3500 ° C. Incidentally, the calorific value per 1 m ³ is about 9,800 Kcal for natural gas and about 12,000 Kcal for LPG gas, but about 18,000 Kcal for electrolytic hydrogen / oxygen gas. Since the combustion product of electrolytic hydrogen / oxygen gas is only water, NOx and CO ₂ are not generated at all.

  For example, a fossil fuel such as LPG causes a kind of explosion phenomenon due to a rapid diffusion of a flame in an attempt to take in oxygen during combustion. However, combustion of electrolytic hydrogen / oxygen gas does not require an external supply of oxygen, so there is no danger of explosion. However, the flame is thin and long as shown in FIG.

  As described above, the flame generated by the combustion of electrolytic hydrogen / oxygen gas is hot but thin. Therefore, although it is suitable for local heating, in order to obtain a high temperature sufficient to burn and melt the object to be processed in the high temperature chamber, it is necessary to diffuse the flame and increase the total heat quantity. Therefore, the combustion of emulsion fuel is used in combination.

  As shown in FIG. 3, the emulsion fuel is blown into a combustion flame of electrolytic hydrogen / oxygen gas from a nozzle 11-2 at the center of the combustion cylinder 11. Then, it is burned by the air supplied from the combustion air supply hole 15. Although the flame temperature is lower than the flame temperature of hydrogen / oxygen gas, the flame temperature reaches 1300 to 1800 ° C. in combination with the combustion of the hydrogen / oxygen mixed gas, and widens in the high temperature chamber 2. The amount of emulsion fuel injected is selected according to the total amount of heat required from the amount of waste to be treated.

  Emulsion fuel is produced with liquid fuel such as light oil and water. These are emulsified by being stirred in a mixer equipped with high-speed rotary blades. At this time, it is desirable to add a small amount of an emulsifier, but an emulsifier is unnecessary depending on the conditions of stirring. The mixing ratio of the liquid fuel and water is desirably a ratio of 0.7 to 1.2 with respect to the fuel 1 in volume ratio. As the liquid fuel, used machine oil (so-called waste oil) or used cooking oil can be used. In addition, the flame temperature can be further increased by supplementarily adding methanol or ethanol.

  The above-mentioned emulsifying device is also desirably provided in the apparatus of the present invention, but the emulsion fuel produced in another place may be transported, stored and used.

  The advantages of using the emulsion fuel in the apparatus of the present invention are as follows.

  (A) of FIG. 5 is the figure which showed typically the combustion form of the emulsion fuel, and (B) each showed the combustion form of the normal fuel (oil). As shown in (a) of FIG. 5A, the emulsion fuel is composed of countless particles having fine water particles 16 as nuclei and the outer surface of which is coated with fuel (oil) 17. When this enters a high-temperature flame in which hydrogen / oxygen gas is burned, it is divided into ultrafine particles and burned, as shown in (c), due to the explosive vaporization of the water that was the core. As a result, the oil burns completely as shown in (d), and the flame spreads greatly.

  On the other hand, normal fuel (oil) that has not been emulsified burns with the oil particles 18 intact, so that the center of the particles cannot be burned as shown in FIG. 5 (B) (d). It remains as carbon particles (煤). Therefore, combustion efficiency is poor and soot is mixed in the exhaust gas.

  For the above reasons, if emulsion fuel is used, a high-temperature flame can be obtained with high combustion efficiency. As described above, air is supplied to the burner 10 from the combustion air supply hole 15. As a part of the combustion air, the combustion exhaust gas sent from the passage 5 as described above is used. Note that the exhaust gas that has been circulated is supplied from the combustion air supply hole 15, but in addition to this, combustion air is also supplied. The air is preferably preheated in the secondary combustion chamber 8 or the like.

  It is desirable to adjust the blow-in amount of the exhaust gas and the air supplied from the outside so that the oxygen in the exhaust gas becomes less than the amount necessary for burning the emulsion fuel. By doing so, there is almost no generation of NOx because there is no excess oxygen in the exhaust gas. On the other hand, since the temperature in the high temperature chamber 2 is extremely high as described above, even if there is PCB contamination in the object to be processed, it is easily decomposed and no dioxin is generated.

  In the high-temperature chamber 2 shown in FIG. 1 and FIG. 2, not only the combustible material in the workpiece is burned by the high-temperature flame from the burner 10 but also the combustion residue and the mixture. Metals and glass are also melted. This melt is discharged from a discharge port 2-1 provided at the bottom of the melting chamber, and is subjected to processes such as cooling and pulverization. The product thus obtained, that is, the waste treatment by-product, is significantly reduced in volume as compared with the combustion residue (ash) from a general incinerator. Therefore, it is advantageous even if landfilled. In addition, since it is once melted, it is stable and does not deteriorate even when it touches water or air. Therefore, even if it is used as a concrete aggregate or a road paving material, secondary pollution is not caused.

  The apparatus shown in FIGS. 1 and 2 is provided with two burners 10, but the number can be increased further. What is necessary is just to change the capability and number of a burner according to the processing capacity of an apparatus.

  The maximum combustion temperature of electrolytic hydrogen and oxygen reaches 3,500 ° C, but only at the center of the flame. In addition, the maximum temperature of the flame that is burned by injecting emulsion fuel into this flame is about 1,800 ° C, but it is lower at the periphery of the flame. Therefore, the inside of the high temperature chamber may be constructed with a refractory used in a general combustion furnace or the like. Further, for example, air for protecting the furnace wall of the high temperature chamber may be blown from the air inlet hole 2-2. Since the flame in the high greenhouse 2 is swirling, this air flows along the wall surface in the room to become a kind of heat insulating material, and prevents the wall surface from overheating. Note that the outside of the apparatus may be covered with an iron skin and a water cooling mechanism may be provided.

  The operation of the apparatus of the present invention may be performed continuously, or may be performed intermittently after waiting for accumulation of the object to be processed (waste) to some extent. As described above, in the apparatus of the present invention, combustion is performed at a very high temperature, so that the processing efficiency is high. Therefore, a large amount of waste can be processed even with a relatively small apparatus.

  The preferred embodiments of the present invention have been described above. The apparatus of the present invention is not limited to the illustrated horizontal type, and can be a vertical type apparatus in which an object to be processed is introduced from above and burned and melted in a high temperature chamber at the lower end. In either case, the above-mentioned special burner is installed in the high temperature chamber to burn electrolytic hydrogen / oxygen gas and emulsion fuel.

  Although the scale (capability) of the apparatus of the present invention can be adjusted according to the processing amount, waste can be efficiently processed even with a relatively small apparatus. Moreover, the exhaust gas is clean and harmless, for example, the NOx content is 20 ppm, and the processing residue is small and does not contain harmful substances. Therefore, the device of the present invention can be installed near a place where waste is generated, such as in the suburbs of a city or in a factory. Moreover, since the combustion efficiency is high, the operation cost is also low.

  According to this apparatus, it is possible to incinerate waste without further separation. It can also be used to treat sludge remaining in wastewater treatment equipment and contaminated soil, and can also be used to reduce the volume and detoxify the combustion residue (ash) coming out of a general incinerator.

It is a longitudinal cross-sectional view which shows an example of this invention apparatus. It is the sectional view on the AA line of FIG. It is a figure which shows notionally the combustion form by the burner used for this invention apparatus. It is a figure which shows the structure of the burner used for this invention apparatus. It is a figure explaining the combustion principle of emulsion fuel and normal fuel.

Explanation of symbols

1: Preheating chamber, 2: High temperature chamber, 3: Hopper, 4: Pusher, 5: Exhaust gas passage,
6: processing object charging passage, 7: exhaust gas passage, 8: secondary combustion chamber,
9: Cyclone dust remover, 10: Burner

Claims (3)

  A waste treatment apparatus comprising a preheating chamber for a workpiece and a high temperature chamber for burning and melting the preheated workpiece, wherein the high temperature chamber contains hydrogen and oxygen obtained by electrolysis of water. A burner for burning a mixed gas and an emulsified fuel is installed, and the pretreatment of the object to be treated in the preheating chamber is performed by combustion exhaust gas generated in the high temperature combustion chamber. apparatus.   The waste treatment apparatus according to claim 1, further comprising a passage for guiding exhaust gas generated in a high greenhouse to a burner. The waste treatment apparatus according to claim 1 or 2, further comprising an electrolysis apparatus for water for generating a mixed gas of hydrogen and oxygen supplied to the burner and an apparatus for emulsifying the fuel.

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