JP2000329323A - High temperature gasifying furnace structure in waste gasifying processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a furnace structure refined in a high temperature gasifying furnace and hence improve durability of a furnace structure and stabilize furnace conditions in a gasifying processing apparatus that includes a low temperature gasifying furnace, a high temperature gasifying furnace, and a gas cleaning tower for cleaning product gas. SOLUTION: A high temperature gasifying furnace 2 includes a furnace top oxygen introduction inlet 24 for sucking diluted oxygen gas to a furnace top. For a furnace body a cooling jacket 6 is mounted, and an internal layer castable 28 is constructed with good heat conductivity SiC and an innermost castable 29 is constructed with god slug weariness Al2O3 (preferably 10 to 80 weight % Cr2O3-Al2O3). The innermost castable 29 at a furnace top dome is constructed with 10 to 30 weight % Cr2O3-Al2O3 together with a side trunk portion. An annular cooling support 34 is provided while surrounding the throat portion 8 and making contact with a refractory support portion 30. Further, the refractory support portion 30 is formed with a 10 to 80 weight % Cr2O3-Al2 O3 castable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a low-temperature gasification furnace using a fluidized-bed gasification furnace and a high-temperature gasification furnace using a high-temperature oxidation furnace to continuously perform low-temperature gasification and high-temperature gasification of organic waste. The present invention relates to an apparatus for gasification.

[0002]

[Prior Art] Municipal waste, sewage sludge, waste plastic,
At present, very little organic waste such as biomass waste, shredder dust, waste oil, etc. is recycled and used, but there are some that are landfilled untreated. The volume of waste is reduced by incineration incinerators, detoxified, and deposited at final disposal sites.

[0003] In the above incinerators, stoker furnaces and fluidized bed furnaces have been used so far. However, since the air ratio at the time of combustion is high, the amount of exhaust gas is large, and metals discharged from the furnace are Since it was oxidized, it was not suitable for recycling. Although an increasing number of ash melting facilities are being added to such incineration facilities, the construction and operating costs of the entire system have been increased.

To solve such a problem, Japanese Patent Laid-Open No.
SUMMARY OF THE INVENTION The technology of the present invention is to supply organic waste to a fluidized-bed gasification furnace, gasify it at a relatively low temperature, extract valuable metals, and produce gas containing fly ash. Ash is supplied to the subsequent melting and combustion furnace and completely burned at a temperature higher than the melting temperature of the ash, thereby converting the ash into molten slag to reduce the volume and prolonging the life of the landfill site as a stable slag that can be landfilled. It proposes a method of recycling as construction materials. That is, in this method, a flammable gas containing unburned char is generated from waste by a fluidized bed gasifier at the former stage, and supplied to a melting furnace at a later stage to convert ash into molten slag and reduce the temperature of the gas to a high temperature. Expected to completely decompose dioxins by complete combustion in 2
Step processing was performed.

[0005]

However, in the melting combustion furnace of the gasification treatment apparatus in the above-mentioned method, that is, in the high temperature gasification furnace, the solid material is converted into molten slag,
In order to completely decompose dioxins to make them harmless and complete combustion of the gas, the primary gasification stream from a fluidized-bed gasification furnace, that is, a low-temperature gasification furnace, is treated with a gasifying agent such as oxygen.
The treatment is performed at a high temperature of 0 to 1600 ° C.

[0006] In the high temperature gasifier, the primary gasification stream from the low temperature gasifier is blown into the furnace top from the upper side of the combustion chamber, and the primary gasification stream blown into the furnace top is It reacts while descending with a gasifying agent, that is, an oxygen gas flow, which is also blown into the furnace side as a swirling flow. Since the reaction between the combustibles of this primary gasification stream and the oxygen gas stream occurs rapidly, oxygen is insufficient at the furnace top, the temperature does not rise as in the center of the combustion chamber, and the partial combustion reaction zone However, there is a problem that thermal efficiency is suppressed and the temperature of the combustion chamber is varied.

Further, as described above, since the high temperature gasifier is operated at a high temperature, wear of the refractory furnace wall in the furnace becomes a problem, and an improved furnace wall structure for improving durability is required. I was Further, as a conventional cooling method for protecting the furnace wall in such a high-temperature gasification furnace, there has been a method in which a vertical water cooling tube is buried in the furnace body, but there is a bias in the supply of cooling water, Further, the cooling effect on the furnace wall is not always sufficient and stable, and there is a problem that the erosion of the furnace wall refractory by the molten slag is difficult to control. In particular, there is a problem that it is difficult to use such a water-cooled pipe protection means since the slag flow-down portion below the combustion chamber has a so-called different diameter structure.

Further, when a cooling jacket is provided on the furnace wall of a high-temperature gasifier, the supply position of a cooling medium such as cooling water is biased with a simple cooling jacket that only covers an outer shell. Therefore, there is a bias in the temperature and internal pressure distribution, and especially when water is used as the medium, the vapor pressure of water is high, and the rise in temperature will cause a significant increase in the external pressure applied to the furnace body such as steel. In addition, there is a problem that HCl in the generated gas in the furnace is locally condensed due to uneven cooling effect, and the furnace inner wall is damaged.

Further, the secondary gasification stream from the high-temperature gasification furnace contains fly ash mainly composed of a large amount of slag particles, and particularly targets H ₂ (hydrogen) and CO (carbon monoxide). If the purpose is to recover it as a useful gasification resource,
Since it contains impurities such as HCl (hydrogen chloride) together with the water droplets, it is necessary to completely remove the fly ash and to remove the impurities, and there has been a situation where further improvement in gas cleaning efficiency is expected.

In view of the above situation, the present invention accepts a primary gasification stream from a low-temperature gasifier, performs complete decomposition of harmful gas components such as dioxin by high-temperature partial combustion treatment, and performs H ₂ and CO ₂ removal. In the high-temperature gasification furnace of the waste treatment equipment that aims to collect the generated gas and completely recover the non-combustible slag, the top of the furnace functions as a partial combustion reaction zone to improve the thermal efficiency and improve the entire high-temperature gasification furnace. By providing a refractory furnace wall structure, and by providing a suitable cooling means in the lower part of the combustion chamber, while improving the thermal efficiency and stabilizing the operation in the high-temperature gasification furnace,
It is intended to improve the durability of the furnace body. Another object of the high-temperature gasifier is to adopt a cooling jacket and to equalize the cooling effect of the furnace body by the cooling jacket, thereby improving the durability of the furnace body and stabilizing the operation. It is still another object of the present invention to provide an improved gas cleaning apparatus in a waste gasification processing apparatus that enables complete dust removal and complete cleaning of a secondary gasification stream from a high temperature gasification furnace.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention firstly provides a low temperature gasifier for primary gasification of organic waste at a low temperature, and a method for producing the same from the low temperature gasifier. A waste gasification treatment apparatus comprising a high-temperature gasification furnace for secondary gasification of gas in a high-temperature combustion chamber and a gas cleaning tower for removing and cleaning the obtained secondary gas, wherein the non-reactive gas is present in the combustion chamber. A gasification treatment apparatus for waste, wherein an oxygen inlet for blowing a mixed gas obtained by mixing a gas diluted with a gas into an oxygen gas is provided at the top of the high-temperature gasification furnace. Outer shell is covered with cooling jacket and SiC
The first waste gasification treatment apparatus, which is provided with two layers of an inner layer castable of a system and an innermost castable of an Al ₂ O ₃ system, thirdly, the innermost layer castable is 10-80. Weight% Cr ₂ O ₃ -Al ₂ O ₃ based castable, wherein the waste gasification treatment apparatus according to the second aspect, and fourthly, a side trunk of the combustion chamber and a furnace top dome The innermost castable in the section is 10 to 30
The gasification apparatus of the waste according to claim 1, characterized in that the _{weight% Cr 2 O 3 -Al 2 O} 3 based castable, fifth, primary gasification of organic waste at a low temperature Waste gas, comprising: a low-temperature gasification furnace to be gasified, a high-temperature gasification furnace to gasify the gas from the low-temperature gasification gas into a secondary gas in a high-temperature combustion chamber, and a gas cleaning tower to remove and clean the obtained secondary gas. A gasification treatment apparatus, wherein the high-temperature gasifier is connected to a quenching chamber for cooling product gas through a throat portion below a combustion chamber, and contacts a refractory support portion at a lower portion of the combustion chamber, and A sixth aspect of the present invention is directed to a waste gasification treatment apparatus characterized in that a cooling support is provided so as to surround a throat portion and a cooling medium is circulated. Formed by weight% Cr ₂ O ₃ -Al ₂ O ₃ castable The gasification apparatus of the waste according to the to the first 5, wherein, in the seventh, refractory support portions 20 to 40 wt% Cr ₂ lower the combustion chamber O ₃ -Al ₂
The present invention provides the waste gasification treatment apparatus according to the fifth aspect, wherein the waste gasification treatment apparatus is formed of an O ₃ -based castable. Eighthly, the present invention eighthly provides a low-temperature gasifier for primary gasification of organic waste at low temperature, a high-temperature gasifier for secondary gasification of gas from the low-temperature gasifier at high temperature, A waste gasification treatment apparatus comprising a gas cleaning tower for removing and cleaning the obtained secondary gas, wherein the high-temperature gasification furnace includes a quenching chamber for cooling a generated gas through a throat section below a combustion chamber. The high temperature gasifier is formed by connecting a shell of a furnace wall outer shell with a cooling jacket, and equally dividing a lower portion in the cooling jacket into a plurality of sections in a vertical direction to form a partitioned jacket, and A header pipe for supplying a cooling medium to the division jacket is provided, and a branch pipe of the Hetter pipe is connected to each division jacket via an orifice, and a differential pressure is provided before and after each of the orifices to the division jacket. The cold To provide a gas treatment apparatus of waste characterized in that a structure capable of evenly supplying of the medium. Furthermore, ninthly, the present invention provides a low-temperature gasifier for primary gasification of organic waste at low temperature, and a high-temperature gasifier for secondary gasification of primary gas from the low-temperature gasifier at high temperature. And a gas cleaning tower for removing and cleaning the obtained secondary gas, wherein the gas cleaning tower introduces a gas stream to be cleaned discharged from the high-temperature gasification furnace into a lower part thereof. A gas-liquid mixture cyclone unit, and a two-stage gas scrubber having a sheave-type tray and a collision plate-type tray disposed above the cyclone unit. Tenth, the shelf unit incorporates a sheave type tray and a collision plate type tray in each of two stages, and a sheave type tray and a collision plate type from the upstream side of the gas flow to be cleaned. Before being characterized by being arranged in the order of trays The waste gasification treatment apparatus according to the ninth or tenth aspect, wherein the waste gasification treatment apparatus according to the ninth aspect is, in the eleventh, a venturi scrubber incorporated as a pretreatment apparatus for the gas cleaning tower. Is provided.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings.
As shown in FIG. 1, the waste gasification apparatus of the present invention is configured as a pressurized gasification system and includes a low-temperature gasification furnace 1 and a high-temperature gasification furnace 2 as one set. Perform gasification treatment. The low-temperature gasification furnace 1 fills a fluidized-bed chamber in the lower part of the furnace with a fluidized medium such as sand, and, from below, a non-reactive gas such as steam or carbon dioxide from outside the system (for example, a gas cleaning tower described later). A part of the carbon dioxide gas obtained by treating the cleaning gas with the acid gas removing device may be used) as a fluidizing gas, and the fluidized medium is fluidized to form a fluidized bed. The low-temperature gasification furnace 1 receives organic waste into the furnace by a quantitative supply device 4, and performs gasification of the waste by supplying oxygen as a gasifying agent from below the fluidized bed. The fluidized bed is maintained at a temperature of 550 to 850 ° C., usually about 600 ° C. by combustion of combustibles, and carbon particles such as unburned char together with gas mainly composed of H ₂ , CO, CO ₂ , hydrocarbon gas and steam. Produces a gaseous substance containing a large amount of combustion residue particles. This gaseous matter is supplied from the furnace top to the high temperature gasification furnace 2 via the gas transfer duct 5 as a primary gasification flow.

The high-temperature gasification furnace 2 has a combustion chamber 7 which is covered with a cooling jacket 6, and a quenching chamber 9 is formed at a lower portion through a throat section 8. In the high-temperature gasification furnace 2, the primary gasification stream is supplied from the gas inlet 10 to the furnace top 1.
At the same time, a mixed gas of oxygen gas as a gasifying agent and steam as a diluting gas is introduced from a plurality of locations on the side surface near the gas inlet 10, for example, four locations as shown in the drawing. , So as to form a swirling flow. The primary gasification stream, usually introduced at a temperature of about 600 ° C., has a temperature of 12
It rises to 00-1600 ° C and is usually maintained at about 1350 ° C. Then, harmful chlorine compounds such as dioxin are completely decomposed to generate a synthesis gas mainly composed of CO and H ₂ , and the non-combustible residue is melted to form molten slag and flows down in the combustion chamber 7 together with the generated gas.

Usually, in the case of producing a synthesis gas for a chemical industrial raw material, gasification in the low-temperature gasification furnace and the high-temperature gasification furnace is performed under a pressure of 5 to 90 atm, preferably 10 to 40 atm. Is carried out at normal pressure, and CO
It is also conceivable as a practical method that the gas purification after the conversion into CO ₂ is performed under a pressure of 30 to 40 atm. When the gasification pressure is set to a high pressure, there are advantages that the amount of processing can be increased and the apparatus can be made compact. In addition, there is an advantage that the operation is easy at a low pressure and the equipment cost is reduced.

The quenching chamber 9 of the high-temperature gasification furnace 2 is provided with a wet-wall type downcomer 12 which is connected to the throat 8 of the combustion chamber 7 and hangs down. The cooling water supplied to 13 is caused to flow down while wetting the inner wall of the downcomer 12 with the swirling flow, and the lower part of the quenching chamber 9 is formed in the water tank by the cooling water, and the lower part of the downcomer 12 is formed. It is in a water seal. The molten slag that has flowed down from the combustion chamber 7 falls into the cooling water in the water tank, is rapidly cooled, becomes granulated slag, and is intermittently taken out as coarse slag via the lock hopper 14. The generated gas from the combustion chamber 7 also flows down in the downcomer 12 in a swirling flow, is rapidly cooled by the wetting wall of the downcomer 12 and the cooling water in the lower water tank, and is discharged from the exhaust gas port 15 in the upper part of the quenching chamber 9. The gas is exhausted and supplied as a secondary gasification stream to the gas cleaning tower 3 via a Venturi-type scrubber 16. Note that cooling water containing slag fine particles is extracted from the water tank section of the quenching chamber 9 as slag slurry water, supplied to a sedimentation tank or the like via a reduced-pressure flash drum (not shown), and fine slag is collected. Has been.

The secondary gasification stream exhausted from the high temperature gasification furnace 2 is introduced into the gas cleaning tower 3 through a Venturi scrubber 16. The gas washing tower 3 has a gas-liquid mixture cyclone section 17 at its lower part and a shelf 18 at its upper part. That is, the secondary gasification stream is supplied with a large amount of high-pressure water by the Venturi scrubber 16, is introduced into the gas-liquid mixture cyclone section 17 in a spray state, becomes a swirling flow, and absorbs HCl in the gas into the water, After transferring the fine slag to the water, the water separates and rises through the central tube 19. Next, the gas flow is applied to the two-stage sheave trays 20 and 2.
It reaches the shelf step portion 18 consisting of a stepped collision plate type tray 21,
The fine slag and HCl in the gas not completely separated by the gas-liquid mixture cyclone unit 17 are further removed, and the entrained mist is removed by the demister 22 at the top of the washing tower, and then discharged outside the tower as a washing gas.

The cleaning gas subjected to the dust cleaning is H ₂
And a synthesis gas mainly containing CO and steam, CH ₄ , CO _{2, and the} like. After being condensed and separated in a gas cooling step (not shown), it is sent to a gas purification step and the like. The water separated from the gas-liquid mixture cyclone section 17 is supplied to the gas washing tower 3
And is circulated and used as cooling water in the quenching chamber 9 of the high temperature gasifier 2. Slag slurry water containing fine slag extracted from the bottom of the gas-liquid mixture cyclone unit 17 is supplied to a sedimentation tank or the like via a not-shown depressurized flash drum, and fine slag is collected.

The waste gasification treatment apparatus according to the present invention is configured as described above. Further, referring to FIG. 2, in the high temperature gasification furnace 2, the combustion chamber 7 A primary gasification stream containing unburned char from the low-temperature gasification furnace 1 is introduced in a tangential direction, and hence as a swirl flow, from a nearby gas inlet 10 to produce a non-reactive gas such as steam, carbon dioxide gas, nitrogen gas, or the like. An oxygen mixed gas of a dilution gas and oxygen by one or more of these gases is similarly introduced as a swirling flow from a plurality of (four) oxygen inlets 23 provided at the same level near the gas inlet 10. (In FIG. 2, three oxygen inlets are particularly shown at different levels to indicate that there are a plurality of oxygen inlets 23).

The primary gasification stream introduced at about 600 ° C.
The combustible gas, unburned char, and the like are combusted by the rapid reaction with the oxygen mixed gas flow while descending in the swirling state, and the secondary gasification further proceeds at a temperature of about 1350 ° C. The generated secondary gasification stream descends in the furnace together with the molten slag flow, is quenched by the supplied cooling water in the quenching chamber 9 provided in the lower part of the combustion chamber 7, and has an exhaust gas port 1 in the upper part of the quenching chamber 9.
5 (FIG. 1), which is led out of the furnace and supplied to the gas cleaning tower 3 via a Venturi-type scrubber 16.

However, in this high temperature gasifier 2,
There is a problem that oxygen is insufficient at the furnace top 11, the partial combustion action is difficult to be performed, the ambient temperature of the furnace top 11 decreases, the furnace does not function effectively as a partial combustion reaction zone, and the temperature of the combustion chamber 7 tends to fluctuate. Therefore, in the present invention, as described above, in addition to supplying the oxygen mixed gas obtained by mixing the oxygen gas and steam as the diluting gas from the oxygen inlet 23 on the side surface near the gas inlet 10, particularly, An oxygen mixed gas of oxygen gas and at least one of non-reactive gases such as steam, carbon dioxide gas, and nitrogen gas for diluting the oxygen gas is supplied from a furnace oxygen inlet 24 provided at the furnace top. . By the supply of the oxygen mixed gas, the temperature at the furnace top 11 is increased to prevent a decrease in the ambient temperature at the furnace top 11,
It can suppress temperature fluctuations and the like in the furnace.
Therefore, the furnace top 11 can also function effectively as a partial combustion reaction zone.
It becomes easier to balance with the amount of oxygen blown from
Prevention of unstable operation becomes easy.

The oxygen mixed gas of the non-reactive gas mixture from the furnace top oxygen inlet 24 is 5 to 5 times the total oxygen amount of the combined oxygen mixed gas of the steam mixture blown from the oxygen inlet 23 on the side of the furnace body. 40% by volume, preferably 5 to
15% by volume. Less effect at less than 5% by volume
If it exceeds 0% by volume, the oxygen mixed gas flow from the side for forming a swirl flow is insufficient, and the residence time required for reacting and decomposing unburned char accompanying the primary gasification flow to a satisfactory degree is reduced. As a result, the effect of swirling the primary gasification stream is reduced, and as a result, the carbon conversion rate is reduced.

Further, the high-temperature gasifier 2 of the present invention is shown in FIG.
As shown in the figure, the outer shell is formed by an iron shell 25,
5 is covered with a jacket 6 having an iron cover 26, and as shown in FIG. 4, the outermost layer of the cooling jacket 6 via the iron cover 26 is a heat insulating material 27 (in FIGS. 2 and 5, the heat insulating material is (Not shown). Further, two layers of castables, that is, an inner layer castable 28 and an innermost layer castable 29 are formed on the inside of the furnace of the iron shell 25. And, the inner layer castable 28 is made of S having relatively high thermal conductivity.
Using an iC type, the innermost castable 29
Al ₂ O ₃ system having high slag wear resistance, particularly preferably 10
８０80 wt% Cr ₂ O ₃ —Al ₂ O ₃ type is used.

During the gasification treatment operation, the combustion chamber 7 of this high-temperature gasification furnace usually has 13
When operating at a temperature of 50 ° C., for example, when water is used as a cooling medium, cooling water is supplied to the outer cooling jacket 6 to generate steam of 1.8 MPaG inside and a furnace internal pressure of 1. At 6 MPaG, the temperature inside the cooling jacket 6 is kept constant at 210 ° C. As the cooling water of the cooling jacket 6, the condensed water of the steam used for the indirect heating in the waste gasification treatment system is collected, and the boiler water stored in the boiler water tank 30 (FIG. 1) is effectively circulated. It's being used. Cooling jacket 6
Is set to 210 ° C. because the furnace pressure is 1.6
The dew point of HCl in MPaG is about 160 ° C., and in order to prevent local condensation of HCl gas in the gas generated in the furnace,
Considering the degree of safety of 50 ° C., determining the appropriate temperature in consideration of the temperature distribution of the castable layer in the furnace, and also the steel shell 25 and the inner wall 25 constituting the inner wall of the cooling jacket 6 It is considered that the iron cover 26 is a carbon steel plate and requires a temperature of 300 ° C. or less from the heat resistance.

The melting point of the produced slag in the treatment of organic waste is about 1100 to 1300 ° C. in terms of its components, and the non-combustible residue easily melts and flows down at a combustion chamber temperature of 1350 ° C. When the innermost layer castable 29 is shaved and reduced in thickness due to the erosion action of the falling molten slag, 2
When the temperature of the inner wall surface falls to about the melting point of the slag, the molten slag that has come into contact with the slag is cooled and solidified and adheres to the furnace wall. to repair. That is, slag self-coating is performed.

As described above, in the furnace wall structure of the high-temperature gasifier 2 of the present invention, the inner layer castable 28 is made of a SiC castable having relatively high thermal conductivity, and the innermost layer castable 29 is eroded by molten slag. Even if the wall thickness is reduced, the inner layer castable 2
Since 8 transfers heat quickly to the cooling jacket 6 maintained at 210 ° C., the slag self-coating action in the innermost castable 29 works early to repair the furnace inner wall. This inner layer castable 28 of SiC system
Does not directly contact the molten slag in the furnace,
In particular, it can be used without having to consider slag wear resistance. Since SiC is vitreous, the innermost castable 29 is worn out by any chance and this SiC-based inner castable 2
Even if the slag 8 comes into contact with the molten slag, it also has the advantage of increasing heat resistance and suppressing erosion by being glassy.

As for the temperature gradient at the furnace wall, as shown in FIG. 4, the gas temperature in the combustion chamber A is 1350 ° C.
When the temperature of the cooling jacket 6 is maintained at about 210 ° C. (the temperature of the outside air G is 15 ° C.), the temperature of the inner surface B of the innermost castable 29 having a thermal conductivity (kcal / mh ° C.) of 1.66 is 1321 ° C. The temperature of the inner surface C of the inner layer castable 28 whose thermal conductivity (kcal / mh ° C.) is 8.76 is 309 ° C., the temperature of the inner surface D of the iron shell 25 is 226 ° C., the temperature of the cooling jacket surface E is 212 ° C. When the temperature of the inner surface F of the material 27 is 209 ° C. and the thickness of the innermost castable 29 is reduced to about １ ／, the temperature of the cooling jacket 6 is maintained at about 210 ° C. The heat transfer effect of the inner layer castable 28 of the system works, and the slag is self-coated,
The iron skin 25 is also sufficiently protected. That is, about 1
The temperature of the inner surface B1 of the innermost castable 29 reduced to / 3 is 1277 ° C., the temperature of the inner surface C1 of the inner castable 28 is 493 ° C., the temperature of the inner surface D1 of the iron shell 25 is 256 ° C.,
The temperature of the cooling jacket surface E1 is 217 ° C., and the maximum thickness reduction position is secured in the innermost layer castable 29.

In addition, erosion by molten slag is suppressed.
First, the innermost castable 29 is Al _TwoO_ThreeSystem stub
And Preferably, 10 to 80% by weight Cr_TwoO_Three-A
l_TwoO_ThreeIt is a system castable. In particular, the side shell of the combustion chamber 7
Cr and Cr at the top dome_TwoO_ThreeIs usually 10
-30% by weight, preferably about 15% by weight.
It is preferable to construct with the adjustable 29 in terms of slag wear resistance.
Good.

Further, in the refractory support portion 31 in the lower part of the combustion chamber shown in FIG. 3, the furnace wall forms a different diameter portion, and the cooling effect by the cooling jacket 6 cannot be expected, and the molten slag flowing down is worn away by erosion. 10% to 80% by weight of Cr ₂ O ₃ —Al ₂ from the viewpoint of slag wear resistance.
The O ₃ -based precast 32, preferably Cr ₂ O _3, is usually 20 to 40% by weight, more preferably 30% by weight. A brick state may be used instead of the precast 32. If this Cr ₂ O ₃ is, for example, 20% by weight or less, the slag wear resistance is not sufficient, and
For example, if it is 40% by weight or more, it becomes expensive and disadvantageous in terms of economy.

Further, in the high-temperature gasifier of the present invention, as shown in FIGS. 2 and 5, at least one or more cooling coils 33 are provided near the throat portion 8 below the combustion chamber 7. is there. That is, the cooling coil 33
Is castably embedded so as to surround a narrow portion at the lower part of the combustion chamber 7, that is, a throat portion 8. When the number of cooling coils 33 is two or more, each cooling coil 33 is independently provided, and each is provided with a water pipe 34 on the outer peripheral side and led out of the furnace.

Further, the cooling support 35 for the annular pipe made of carbon steel is connected to the iron plate supporting the bottom of the refractory support portion 31 and surrounds the throat portion 8.
Is provided. That is, the cooling support 35 which is located below the cooling coil 33 and supports the refractory support portion 31 is formed in an annular cooling pipe having a somewhat flat and large cross section, and the cooling water is provided. A greater cooling effect is obtained for circulation.

The cooling water supplied to the cooling coil 33 and the cooling support 35 is supplied at a temperature of 40 to 60 ° C. and is discharged as it is, unlike the cooling jacket 6, so that the refractory support portion 31 is cooled. The castables can be cooled sufficiently. As described above, the effect of arranging the cooling support 35 together with the cooling coil 33 on the refractory support portion 31, which has a different diameter portion at the lower portion of the combustion chamber 7 and has no cooling medium as described above, is great. There is something. By forming metal fins outside the cooling coil 33 and inside the furnace of the cooling support 35, the thermal conductivity can be further improved, and the castability can be further improved.

As shown in FIGS. 1 and 2, cooling water is supplied to a cooling jacket 6 of the high-temperature gasification furnace 2 from a cooling water inlet nozzle 36 provided at a lower portion. A part of the steam is turned into steam mixed cooling water, which is discharged from a steam mixed water outlet nozzle 37 above the cooling jacket 6. The discharged steam mixed cooling water separates steam in the steam separator 38 as shown in FIG.
Discharge out of the system through 0. The cooling water from which the steam has been separated is circulated again toward the cooling jacket 6. Regarding the insufficient water due to the separation of the steam, the boiler water is supplied from the boiler water tank 30 to the steam separator 38. is there.

The temperature of the cooling jacket 6 is maintained at 210 ° C. by controlling the pressure in the jacket system to 1.8 MPaG by controlling the control valve 40 of the steam separation pipe 39. Although the cooling effect by using water as a cooling medium is great, the vapor pressure of water is large, and the external pressure applied to the furnace body such as steel becomes significant due to the high temperature of the cooling water. Controlling the pressure in the jacket system and keeping the temperature of the cooling water at 210 ° C. is also important for protecting the furnace body of the high temperature gasification furnace 2 such as the iron shell.

Therefore, in the present invention, in particular, the lower portion of the cooling jacket 6 is equally divided into a plurality of portions so that the cooling water can be uniformly supplied in a pressurized state.
The bias of the pressure and temperature distribution at the point is eliminated. That is, as shown in FIG. 6, a vertical partition corresponding to the size of the furnace is provided at a lower portion in the cooling jacket 6 to divide the cooling jacket 6 into a plurality of (eight in FIG. 6) compartment jackets 6a. Supply cooling water,
The cooling water amount and the internal pressure can be controlled equally. The partition having an intermediate height of the cooling jacket 6 is sufficient, and the upper part of the cooling jacket 6 does not particularly need a partition because the generated steam is sufficiently diffused in pressure.

As shown in FIG. 7A, a supply header pipe 41 is provided so as to surround the lower part of the combustion chamber 7 of the high-temperature gasification furnace 2.
Are connected to the cooling water inlet nozzles 36 of the respective compartment jackets 6a of the cooling jacket 6 through the orifices 43 (FIG. 1), and the circulating cooling water from the steam separator 38 is supplied to the cooling water inlet nozzles 36. The cooling water can be supplied to the cooling jacket 6 via the supply header pipe 41. By providing a differential pressure of about 0.1 MPa before and after the orifice 43, the cooling water is supplied to each of the divisional jackets 6a.
So that they can be evenly supplied. That is, with this configuration, it is possible to uniformly and sufficiently control the internal pressure and the temperature of the cooling jacket.

On the upper side of the high temperature gasifier 2 from which the steam mixed water is discharged, as shown in FIG. 7 (b), a discharge header pipe 44 is provided so as to surround the upper part of the combustion chamber 7, and The header pipe 44 and the upper part of the cooling jacket 6 are connected by a plurality (four in the figure) of branch pipes 45. Steam mixed water containing steam in which a part of the cooling water supplied in the cooling jacket 6 is evaporated is discharged from the steam mixed water outlet nozzle 37 via the discharge header pipe 44.

In the high-temperature gasification furnace of the present invention, as described above, the holding temperature of the cooling jacket is determined by the HC in the generated gas.
Because of the necessity of increasing the dew point with a margin,
The temperature is set at about 0 ° C., and water such as boiler water is used as a typical cooling medium. However, as a method of using the heat transfer medium, there are a gas-phase heating method in which steam is generated and steam is transferred similarly to water, and a liquid-phase method in which the heat is circulated by a pump and cooled by sensible heat. Examples of the liquid phase heat transfer medium include, in addition to water, alkyl naphthalene, alkyl benzene, a eutectic mixture of diphenyl and diphenyl ether, and the like, and the liquid phase heat transfer medium includes, for example, alkali naphthalene, hydrogen Triphenyl chloride, dibenzyltoluene, and paraffinic mineral oil.

When the temperature is high, by using a heat transfer medium (chemical) having a small saturated vapor pressure, the external pressure applied to the outer shell of the combustion chamber of the high temperature gasifier is greatly reduced, and the thickness of the outer shell is reduced. There is a merit that can be done. When the heat transfer medium is used in a gas phase heating method, a condenser (condenser) is required, and when the heat transfer medium is used in a liquid phase method, a cooler is required. It is considered that the method using water as the heat transfer medium is simple and reliable.

As shown in FIG. 1, the exhaust gas flow from the quenching chamber 9 of the high temperature gasifier 2, that is, the secondary gasification flow is accompanied by slag particles. This secondary gasification stream is first introduced into a venturi scrubber 16. In the venturi scrubber 16, the gas flow is accelerated to high-speed turbulence, and at the same time, a large amount of high-pressure circulating water is sprayed to impinge slag particles on the dispersed water droplets and remove HCl in the gas.
To absorb. The high-speed gas flow from the venturi scrubber 16 is a mixed gas flow of a solid, liquid, and gas containing a large amount of liquid, and is supplied to the gas cleaning tower 3 as it is.

As shown in FIG. 8, the gas cleaning tower 3 is supplied with the high-speed gas flow at the gas-liquid mixture cyclone section 17.
The high-speed gas flow enters the tower tangentially from the gas liquid inlet 46 and forms a swirling flow, descends spirally in the tower, during which water and slag particles in the gas flow are Due to the centrifugal force, it descends along the inner wall and accumulates at the bottom of the tower, and the gas flow rises through the central pipe 47.

A shelf 18 is provided above the gas cleaning tower 3. The shelf 18 comprises a combination of a two-stage sheave type tray 20 provided on the lower side in a shelf shape and a two-stage collision plate type tray 21 provided on the upper side in a shelf shape. As shown in FIG. 9, the sheave-type tray 20 is a perforated plate having a large number of minute sheave holes 48 formed therein, and a step portion is formed by a hanging plate 49 having one end vertically bent downward. It is. The numerous sieve holes 48 are arranged in a regular manner so that the gas can pass uniformly and without bias. Also,
The sheave holes 48 in the two-stage sheave type tray 20 have the same diameter (sheet hole diameter 7 mm at a tray diameter of 1,300 mm), but the pitch is slightly changed. Also, the upper and lower hanging plates 49
Are in opposing positions when viewed from above.

Further, as shown in FIGS. 10 and 11A and 11B, the collision plate type tray 21 is a combination of a sheave plate 50 and a collision plate 51, respectively. Is the sheave type tray 2 shown in FIG.
This is a perforated plate in which a number of minute sheave holes 52 are formed in a similar manner to 0. In the collision plate 51, a number of slits 53 are provided in parallel. The collision plate 51 is fixed on the upper surface side of the sheave plate 50 at predetermined intervals by bolts 55 with a spacer 54 interposed therebetween so that the row of the sheave holes 52 and the slit 53 do not overlap. Further, similarly to the sheave type tray 20, the two sets of sheave plates 50 are provided with a stepped portion formed by a hanging plate 56 at one end facing each other.

As shown in FIG. 8, cleaning water is supplied from a cleaning water nozzle 57 to the upper surface of each of the set collision plate type tray 21 and sheave type tray 20. The water flows on the upper surface of the sheave plate 50 of the tray 21 and the upper surface of the sheave type tray 20 so as to form a water film, and flows down through the hanging plates 49 and 56 to the lower stage. The separated water from the demister 22 is caused to flow downward by the drain pipe 58, and the separated water from the shelf 18 is caused to flow by the drain pipe 59 to the lower part of the tower in a bypass manner and stored in the outer peripheral part of the top of the central pipe 47. Separated water from the rising gas stream is drained 60
To flow down to the lower part of the tower. Further, the slag slurry water is discharged from the slag slurry water outlet 61 at the bottom of the tower.

Therefore, the rising gas flow from the gas-liquid mixture cyclone section 17 passes through the sheave holes 48 of each sheave type tray 20 through the water film of the washing water, and flows through the sheave holes 48. Then, after passing through the sheave hole 52 of the sheave plate 50 in the collision plate type tray 21, it collides with the collision plate 51, and is further bent to form a slit 53.
Ascend through. During this time, fine slag particles in the gas stream are separated along with the water stream, and HCl in the gas stream is further absorbed by the water stream and flows downward, thereby being separated from the gas stream. And the gas flow is
The gas entrainment mist is separated by passing through the demister 22 above the shelf 18 and discharged as a cleaning gas stream from the gas outlet 62 at the top.

In the gas cleaning tower 3 described above, the gas introduction part is the gas-liquid mixture cyclone section 17, and the conventional structure of the two-stage collision plate type tray for dust removal is different from that of the gas cleaning tower 3.
The combination of the sheave type tray 20 and the collision plate type tray 21 is a two-stage combination. Preferably, a combination of the gas-liquid mixture cyclone unit 17 and the Venturi type scrubber 16 is provided before the cyclone unit 17. In the humidified state of the secondary gasification stream, the acidic component HCl
It actively removes solids and removes solid slag particles. Thoroughly separates solids, liquids, and gases, and has a simple structure, is inexpensive, has low pressure loss, and is economical. Has advantages.

[0046]

According to the present invention, in the high temperature gasifier, the vicinity of the gas inlet is
In addition to the oxygen inlet, an oxygen inlet is also provided
According to the present invention, oxygen gas is blown from the furnace top.
For example, the furnace top can be used as a partial combustion reaction zone,
This has the effect of stabilizing the temperature and improving the thermal efficiency.
In the high temperature gasifier, the inner layer of the refractory wall of the combustion chamber is
Al with high lug wear _TwoO_ThreeSystem, especially 10-80% by weight C
r_TwoO_Three-Al_TwoO_ThreeSystem castable and S with high thermal conductivity
Two-layer castable structure with iC castable
According to the present invention, the cooling effect of the exterior cooling jacket is
The slag self-coating is activated early
Has the effect of improving the durability of the furnace wall
You. Also, at the side body of the combustion chamber and the top dome
The innermost layer castable, especially 10 to 30% by weight Cr_TwoO_Three
-Al_TwoO_ThreeAccording to the present invention configured with a diameter castable,
The slag wear resistance at these locations is improved, and the furnace wall
The effect that durability is improved is produced.

Further, according to the present invention, in which the cooling support in contact with the refractory support portion is provided in a state surrounding the throat portion at the lower portion of the combustion chamber so that the water can be actively cooled, the cooling effect at the portion is enhanced. This has the effect of improving the durability of the furnace wall. Furthermore, the refractory support of the cooling effect is hardly combustion chamber bottom utilization of the cooling jacket of the furnace wall, 10 to 80 wt%, preferably 20 to 40 wt% of Cr ₂ O ₃ -Al ₂ O ₃ diameter ADVANTAGE OF THE INVENTION According to this invention comprised by the castable, the slag wear resistance in this refractory support part is improved, and there exists an effect that the durability of a furnace body improves.

Further, according to the present invention, the lower portion inside the cooling jacket is constituted by a division jacket, and the cooling medium can be evenly supplied to each division jacket by the header pipe means having an orifice interposed therebetween. It is performed evenly, the internal pressure and temperature in the cooling jacket can be controlled evenly and sufficiently, and the dew condensation of HCl in the generated gas is prevented, and the safety of the furnace body such as iron shell is improved.
In addition, there is an effect that the operation is stabilized.

Further, in a gas cleaning apparatus for cleaning a secondary gasification stream from a high temperature gasification furnace, a combination of a gas-liquid mixture cyclone mechanism, a sheave type tray, and a shelf mechanism using a collision plate type tray is used. In particular, in the latter shelf mechanism, the sheave type tray and the collision plate type tray are configured in two stages in a predetermined permutation, and further, a venturi scrubber is provided in front of the gas-liquid mixture cyclone mechanism. ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the gasification treatment apparatus of the organic waste which can completely absorb and remove HCl from a refinement | purification secondary gas and collect | recover slag particles is obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a main part of a gasification treatment apparatus of the present invention.

FIG. 2 is a sectional view showing a combustion chamber portion of the high temperature gasifier of FIG.

FIG. 3 is a schematic sectional view showing a refractory structure of the high temperature gasifier in FIG.

FIG. 4 is a partial cross-sectional view showing a configuration of the refractory structure of FIG. 3 and a temperature distribution thereof.

FIG. 5 is a partial sectional view showing a lower structure of a combustion chamber of the high temperature gasifier of FIG. 1;

FIG. 6 is a conceptual diagram showing a horizontal cross section of a cooling jacket of the high temperature gasifier of FIG.

7 is a conceptual diagram showing a cross section of a cooling jacket and a cooling water supply system in the high temperature gasification furnace of FIG. 1, wherein (a) is a system of a cooling water inlet, and (b) is a system of cooling water and steam. It is a system of the mixing outlet.

FIG. 8 is a cross-sectional view of the gas cleaning tower in FIG.

9 is a plan view of a sheave type tray in the gas cleaning tower of FIG.

FIG. 10 is a partial plan view of a collision plate type tray in the gas cleaning tower of FIG. 8;

11 shows a collision plate type tray in the gas cleaning tower of FIG. 8, (a) is a partial plan view thereof, and (b) is b of (a).
It is sectional drawing which follows the -b line.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low temperature gasifier 2 High temperature gasifier 3 Gas washing tower 6 Cooling jacket 6a Division jacket 7 Combustion chamber 8 Throat part 9 Quench chamber 10 Gas inlet 11 Furnace top 12 Downcomer 13 Injection weir 14 Lock hopper 15 Exhaust port 16 Venturi Type scrubber 17 Gas-liquid mixture cyclone 18 Shelf 19 Central tube 20 Sheave tray 21 Collision plate tray 22 Demister 23 Oxygen inlet 24 Furnace oxygen inlet 25 Iron shell 26 Iron cover 27 Heat insulator 28 Inner layer castable 29 Inner layer castable 30 Boiler water tank 31 Refractory support part 32 Precast 33 Cooling coil 34 Water pipe 35 Cooling support 36 Cooling water inlet nozzle 37 Steam mixed water outlet nozzle 38 Steam separator 39 Steam separation line 40 Control valve 41 Supply header pipe2 branch pipe 43 orifice 44 discharge header pipe 45 branch pipe 46 gas liquid inlet 47 central pipe 48 sheave hole 49 hanging plate 50 sheave plate 51 collision plate 52 sheave hole 53 slit 55 bolt 56 hanging plate 57 washing water nozzle 59 drain pipe 61 Slag slurry water outlet 62 Gas outlet

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] March 8, 2000 (200.3.8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] High temperature gasification furnace structure in waste gasification equipment

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a low-temperature gasification furnace using a fluidized-bed gasification furnace and a high-temperature gasification furnace using a high-temperature oxidation furnace to continuously perform low-temperature gasification and high-temperature gasification of organic waste. The present invention relates to a gasification apparatus to be performed, and particularly to a structure in a high-temperature gasification furnace.

[0002]

[Prior Art] Municipal waste, sewage sludge, waste plastic,
At present, very little organic waste such as biomass waste, shredder dust, waste oil, etc. is recycled and used, but there are some that are landfilled untreated. The volume of waste is reduced by incineration incinerators, detoxified, and deposited at final disposal sites.

[0003] In the above incinerators, stoker furnaces and fluidized bed furnaces have been used so far. However, since the air ratio at the time of combustion is high, the amount of exhaust gas is large, and metals discharged from the furnace are Since it was oxidized, it was not suitable for recycling. Although an increasing number of ash melting facilities are being added to such incineration facilities, the construction and operating costs of the entire system have been increased.

To solve such a problem, Japanese Patent Laid-Open No.
SUMMARY OF THE INVENTION The technology of the present invention is to supply organic waste to a fluidized-bed gasification furnace, gasify it at a relatively low temperature, extract valuable metals, and produce gas containing fly ash. Ash is supplied to the subsequent melting and combustion furnace and completely burned at a temperature higher than the melting temperature of the ash, thereby converting the ash into molten slag to reduce the volume and prolonging the life of the landfill site as a stable slag that can be landfilled. It also proposes a method for recycling as construction materials. That is, in this method, a flammable gas containing unburned char is generated from waste by a fluidized bed gasifier at the former stage, and supplied to a melting furnace at a later stage to convert ash into molten slag and reduce the temperature of the gas to a high temperature. To perform a two-stage treatment to expect complete decomposition of dioxins.

[0005]

However, in the melting combustion furnace of the gasification treatment apparatus in the above-mentioned method, that is, in the high temperature gasification furnace, the solid material is converted into molten slag,
In order to completely decompose dioxins to make them harmless and complete combustion of the gas, the primary gasification stream from a fluidized-bed gasification furnace, that is, a low-temperature gasification furnace, is treated with a gasifying agent such as oxygen.
The treatment is performed at a high temperature of 0 to 1600 ° C.

In the high-temperature gasification furnace, the primary gasification stream from the low-temperature gasification furnace is blown into the furnace top from the upper side of the combustion chamber, and the primary gasification stream blown into the furnace top is blown. Is made to react while descending with a gasifying agent, that is, an oxygen gas flow, which is also blown into the furnace side as a swirling flow. The reaction between the combustibles of this primary gasification stream and oxygen gas occurs rapidly, so the oxygen in the top of the furnace is insufficient, the temperature does not rise as in the center of the combustion chamber, and it is substantially a partial combustion reaction zone. Has a problem that it does not function, suppresses thermal efficiency, and is also a factor of fluctuation of the combustion chamber temperature.

Further, as described above, since the high temperature gasifier is operated at a high temperature, wear of the refractory furnace wall in the furnace becomes a problem, and an improved furnace wall structure for improving durability is required. I was Further, as a conventional cooling method for protecting the furnace wall in such a high-temperature gasification furnace, there has been a method in which a vertical water cooling tube is buried in the furnace body, but there is a bias in the supply of cooling water, Further, the cooling effect on the furnace wall is not always sufficient and stable, and there is a problem that the erosion of the furnace wall refractory by the molten slag is difficult to control. In particular, there is a problem that it is difficult to use such a water-cooled pipe protection means since the slag flow-down portion below the combustion chamber has a so-called different diameter structure.

[0008] The present invention has been made in view of the above situation, receiving a primary gasification stream from the low temperature gasifier, the hot combustion process, H ₂ or CO or the like together with a complete decomposition treatment such as dioxin toxic gas components In the high-temperature gasifier of the waste treatment equipment that collects the generated gas and completely recovers the incombustible slag, the thermal efficiency is improved by making the furnace top function as a partial combustion reaction zone, and the entire high-temperature gasifier is improved. By providing a refractory furnace wall structure that has been improved, and by providing suitable cooling means in the lower part of the combustion chamber, it is possible to improve the thermal efficiency and stabilize the operation of the high-temperature gasifier and improve the durability of the furnace body. It is intended for.

[0009]

Means for Solving the Problems To achieve the above object,
First, the present invention firstly removes organic waste from primary gas at low temperatures.
Low-temperature gasifier to be converted to gas, and gas from the low-temperature gasifier
A high-temperature gasifier for secondary gasification in a high-temperature combustion chamber
Gas cleaning tower that removes and cleans the secondary gas
High temperature gasification furnace structure of waste gasification equipment,
Mix the dilution gas with non-reactive gas with oxygen gas in the combustion chamber.
The oxygen inlet for injecting the mixed gas into the high-temperature gasifier
Waste gasification treatment equipment provided on the top of
Second, the combustion chamber is outside
The outer shell of the shell is covered with a cooling jacket and the SiC-based
Inner layer castable and Al₂O₃The innermost castable of the system
The first waste gas, wherein the first waste gas is
Third, the high-temperature gasification furnace structure in the
The innermost castable is 10 to 80% by weight Cr.₂O ₃−
Al₂O₃The above castable.
High-temperature gasification in the waste gasification treatment equipment according to the second aspect
Fourth, the furnace structure includes a side body of the combustion chamber and a furnace top dough.
10-30 weights of the innermost castable in the
% Cr₂O₃-Al₂O₃System castable
The waste gasification treatment device according to the first aspect, which is characterized in that
Fifth, organic waste at low temperature
Low-temperature gasifier for primary gasification at the low temperature gasifier
-Temperature gas that converts gas from the gas into secondary gas in a high-temperature combustion chamber
Gas cleaning tower that removes and cleans the obtained secondary gas
-Temperature gasifier for waste gasification equipment consisting ofConstructionIn
Thus, the high temperature gasifier has a throat section below the combustion chamber.
Connected to a quenching chamber that cools the product gas through
Contact the refractory support at the bottom of the combustion chamber and
The cooling medium is provided by surrounding the cooling
Waste gasification treatment equipment characterized in that
Sixth, the structure of the high-temperature gasifier at
10 to 80% by weight Cr_Two O_Three
-Al_TwoO_ThreeCharacterized by being formed of castable
The high temperature in the waste gasification treatment apparatus according to the fifth aspect
Seventh, the gasification furnace structure is changed to a refractory support at the lower part of the combustion chamber.
20-40% by weight Cr_TwoO_Three-Al_TwoO_ThreeSystem
6. The method according to the fifth aspect, which is formed by stubble.
Providing a high-temperature gasification furnace structure for waste gasification equipment
Is what you do.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings.
As shown in FIG. 1, the waste gasification processing apparatus according to the present invention is configured as a pressurized gasification system and includes a low-temperature gasification furnace 1 and a high-temperature gasification furnace 2 as one set. Gasification treatment. The low-temperature gasification furnace 1 fills a fluidized bed chamber at the lower part of the furnace with a fluid medium such as sand, and supplies a non-reactive gas such as steam or carbon dioxide gas from outside the system as a fluidizing gas from below. The fluidized medium is fluidized to form a fluidized bed. The low-temperature gasification furnace 1 receives organic waste into the furnace by a constant-quantity supply device 4 and performs gasification of the waste by supplying oxygen as a gasifying agent from below the fluidized bed. The fluidized bed is 550-850 by combustion of combustibles.
° C., typically maintained at a temperature of about 600 _℃, H _{2, CO,}
A gaseous substance containing a large amount of combustion residue particles other than carbon particles such as unburned char is generated together with a gas mainly composed of CO ₂ , hydrocarbon gas and steam. This gaseous matter is supplied from the furnace top to the high temperature gasification furnace 2 via the gas transfer duct 5 as a primary gasification flow.

The high-temperature gasifier 2 has a combustion chamber 7 which is covered with a cooling jacket 6, and a quenching chamber 9 is formed at a lower portion through a throat section 8. In the high-temperature gasification furnace 2, the primary gasification stream is supplied from the gas inlet 10 to the furnace top 1.
1 enters a tangential direction and forms a swirling flow. At the same time, oxygen gas as a gasifying agent and steam as a diluting gas from a plurality of oxygen inlets 23 on the side surface in the vicinity of the gas inlet 10, for example, four as shown in FIG. A mixed gas is introduced, and oxygen is introduced together with a diluting gas from a furnace top oxygen inlet 24 so as to be swirled with the primary gasification flow.
The primary gasification stream, usually introduced at a temperature of about 600 ° C., has a temperature of 1200 to 1200 due to this partial combustion reaction with oxygen.
It rises to 1600 ° C and is usually maintained at about 1350 ° C. Then, harmful chlorine compounds such as dioxin are completely decomposed, and a synthesis gas mainly composed of CO and H ₂ is generated,
The non-combustible residue is melted into molten slag and flows down in the combustion chamber 7 together with the generated gas.

Usually, when producing a synthesis gas for a chemical industrial raw material, gasification in the low-temperature gasification furnace and the high-temperature gasification furnace is performed under a pressure of 5 to 90 atm, preferably 10 to 40 atm. the carried out at normal pressure, it is believed to CO in the product gas as a realistic way also be carried out under a pressure of 30-40 atm gas purification after being converted to CO _2. When the gasification pressure is set to a high pressure, there are advantages that the amount of processing increases and that the apparatus can be made compact. Also,
At low pressure, there is an advantage that the operation is easy and the equipment cost can be reduced.

The quenching chamber 9 of the high-temperature gasification furnace 2 is provided with a wet-wall type downcomer 12 which is connected to the throat 8 of the combustion chamber 7 and hangs down, and an injection weir provided at the base of the downcomer 12. The cooling water supplied to 13 is made to flow down while wetting the inner wall of the downcomer pipe 12 with the swirling flow, and the lower part of the quenching chamber 9 is formed in a water tank by this cooling water.
The lower part of the downcomer 12 is in a water-sealed state. The molten slag that has flowed down from the combustion chamber 7 falls into the cooling water in the water tank, is rapidly cooled, becomes granulated slag, and is intermittently taken out as coarse slag via the lock hopper 14. Further, the product gas from the combustion chamber 7 is also supplied to the downcomer 12
The cooling water is quenched by the swirling flow and cooled by the cooling water in the lower water tank and the wetting wall of the downcomer pipe 12.
And is supplied to the gas cleaning tower 3 as a secondary gasification stream. Note that cooling water containing slag fine particles is extracted from the water tank section of the quenching chamber 9 as slag slurry water, supplied to a sedimentation tank or the like via a reduced-pressure flash drum (not shown), and fine slag is collected. Has been.

The secondary gasification stream discharged from the high-temperature gasification furnace 2 is introduced into the gas cleaning tower 3 through a Venturi scrubber 16. The gas washing tower 3 has a gas-liquid mixture cyclone section 17 at its lower part and a shelf 18 at its upper part. That is, the secondary gasification flow is supplied with a large amount of high-pressure water by the Venturi scrubber 16 and is introduced into the gas-liquid mixture cyclone unit 17 in a spray state to form a swirling flow,
The HCl in the gas is absorbed by the water, and the gas stream is separated from the fine slag and the water containing the absorbed HCl and is raised through the central pipe 19. Then the gas flow is 2
The shelf 18 includes a sheave tray 20 having two stages and a collision plate tray 21 having two stages.
The fine slag and HCl in the gas that could not be completely separated in step 7 are further removed, and the accompanying mist is removed by the demister 22 at the top of the washing tower, and then discharged outside the tower as a washing gas.

The cleaning gas subjected to the dust cleaning processing is H ₂
And a synthesis gas mainly containing CO and steam, CH ₄ , CO _{2, and the} like. After being condensed and separated in a gas cooling step (not shown), it is sent to a gas purification step and the like.
Separated water from the gas-liquid mixture cyclone unit 17 is extracted from the bottom of the gas washing tower 3 and is circulated and used as cooling water for the quenching chamber 9 of the high temperature gasification furnace 2. Slag slurry water containing fine slag extracted from the bottom of the gas-liquid mixture cyclone unit 17 is supplied to a sedimentation tank or the like via a not-shown depressurized flash drum, and fine slag is collected.

The waste gasification treatment apparatus according to the present invention is configured as described above. Referring to FIG. 2, in the high temperature gasification furnace 2, the combustion chamber 7 is located near the furnace top 11. A primary gas stream containing unburned char from the low-temperature gasifier 1 is introduced in a tangential direction and therefore as a swirl flow from the gas inlet 10 of the low-temperature gasifier 1, and one of non-reactive gases such as steam, carbon dioxide gas, nitrogen gas, etc. A mixed gas of a diluent gas and oxygen by more than one kind of gas is similarly introduced as a swirling flow from a plurality of (for example, four) oxygen inlets 23 provided at the same level in the vicinity of the gas inlet 10. (In FIG. 2, especially, three oxygen inlets are shown at different levels to show that there are a plurality of oxygen inlets 23).

The primary gasification stream introduced at about 600 ° C.
As it descends in a swirling state, it reacts rapidly with the oxygen gas flow to burn combustible gas, unburned char, etc., for about 1 hour.
Further gasification proceeds at a temperature of 350 ° C. The generated secondary gasification stream descends in the furnace together with the molten slag stream, and
In the quenching chamber 9 at the lower part of the quenching chamber 9, it is quenched by the supplied cooling water, drawn out of the furnace from the exhaust gas port 15 (FIG. 1) at the upper part of the quenching chamber 9, and supplied to the gas cleaning tower 3.

However, in this high temperature gasifier 2,
There is a problem that oxygen is insufficient at the furnace top 11, the partial combustion action is difficult to be performed, the ambient temperature of the furnace top 11 decreases, the partial combustion reaction zone does not function effectively, and the temperature of the combustion chamber 7 tends to fluctuate. Therefore, in the present invention, as described above,
In addition to supplying the mixed gas of the oxygen gas and the steam as the dilution gas from the oxygen inlet 23 on the side surface near the gas inlet 10, in particular, the furnace oxygen inlet 2 provided at the furnace top is used.
A mixed gas of oxygen gas and at least one of non-reactive gases such as steam, carbon dioxide gas and nitrogen gas for diluting the oxygen gas is supplied from 4. By supplying the mixed gas, the temperature at the furnace top 11 can be increased to prevent a decrease in the ambient temperature at the furnace top 11, and the temperature fluctuation in the furnace can be suppressed. Therefore, the furnace top 11 can also be effectively functioned as a partial combustion reaction zone,
Further, the balance with the amount of oxygen blown from the oxygen inlet 23 on the side surface is easily obtained, and the unstable operation is easily prevented.

The flow of the diluted gas mixed oxygen gas from the furnace top oxygen inlet 24 is 5 to 5 times of the total oxygen amount including the diluted gas mixed oxygen gas flow such as steam blown from the oxygen inlet 23 on the side of the furnace body. 40% by volume, preferably 5 to 15%
% By volume. If the content is less than 5% by volume, the effect is small. If the content exceeds 40% by volume, the oxygen gas flow from the side for forming the swirling flow is insufficient, and the reaction decomposition is performed to an extent that the unburned char accompanying the primary gasification flow can be satisfied. Therefore, the effect of swirling the primary gasification stream so as to secure the necessary residence time is reduced, and as a result, the carbon conversion rate is reduced.

Further, the high-temperature gasifier 2 of the present invention has a structure shown in FIG.
As shown in FIG. 4, the outer shell is formed of an iron shell 25, and the iron shell 25 is covered with the cooling jacket 6, and as shown in FIG. The outermost layer is a heat insulating material 27 (in FIGS. 2 and 5,
The illustration of the heat insulating material is omitted). Also, 2
The layers are castable, that is, the inner layer castable 28 and the innermost layer castable 29 are provided. The inner layer castable 28 is made of a SiC material having relatively high thermal conductivity, and the innermost layer castable 29 is made of an Al ₂ O ₃ material having high slag wear resistance, particularly preferably 10 to 80% by weight of Cr. _{A 2} O ₃ —Al ₂ O ₃ type is used.

During the gasification treatment operation, the combustion chamber 7 of this high-temperature gasification furnace is usually 13
When operating at a temperature of 50 ° C. and using water as a cooling medium, for example, by supplying cooling water to the outer cooling jacket 6, steam of 1.8 MPaG is generated inside, and the furnace internal pressure is set to 1. At 6 MPaG, the temperature inside the cooling jacket 6 is kept constant at 210 ° C. As the cooling water of the cooling jacket 6, boiler water collected from steam condensed water used for indirect heating in the waste gasification treatment system and stored in a boiler water tank is effectively circulated and used. The reason for setting the holding temperature of the cooling jacket 6 to 210 ° C. is that the furnace internal pressure is 1.6 MPa.
The dew point of HCl in aG is about 160 ° C., and in order to prevent local condensation of HCl gas in the gas generated in the furnace, 50 ° C.
C., the appropriate temperature is determined in consideration of the temperature distribution of the castable layer in the furnace, and the steel shell 2 forming the inner wall of the cooling jacket 6 is also determined.
It is considered that the steel cover 3 and the iron cover 24 are made of carbon steel and require a temperature of 300 ° C. or less from the heat resistance.

The melting point of the slag produced in the treatment of organic waste is about 1100 to 1300 ° C. in terms of its components, and the non-combustible residue easily melts and flows down at a combustion chamber temperature of 1350 ° C. When the innermost layer castable 29 is shaved and reduced in thickness due to the erosion action of the falling molten slag, 2
When the temperature of the inner wall surface falls to about the melting point of the slag, the contacted molten slag is cooled, solidified and adheres, and the furnace wall is repaired. I do. That is, slag self-coating is performed.

As described above, in the furnace wall structure of the high temperature gasification furnace 2 of the present invention, the inner layer castable 28 is made of a SiC castable having relatively high thermal conductivity, and the innermost layer castable 29 is eroded by molten slag. Even if the wall thickness is reduced, the inner layer castable 2
Since 8 quickly transfer heat to the cooling jacket 6 held in 210 ° C., so that the slag self coating effect in the innermost layer castable 29 in early repair work furnace inner wall. This inner layer castable 28 of SiC system
Does not directly contact the molten slag in the furnace,
In particular, it can be used without having to consider slag wear resistance.
Since SiC is glassy, the innermost layer castable 2
Even if the SiC-based inner layer castable 28 comes into contact with the molten slag due to wear of the steel 9, the glass-like inner layer also has the advantage of increasing heat resistance and suppressing erosion.

Regarding the temperature gradient in the furnace wall, as shown in FIG. 4, the gas temperature in the combustion chamber A is 1350 ° C.
When the temperature of the cooling jacket 6 is maintained at about 210 ° C. (the temperature of the outside air G is 15 ° C.), the thermal conductivity (kcal / mh ° C.) is 1.
The temperature of the inner surface B of the innermost castable 29 of 66 is 132
The temperature of the inner surface C of the inner layer castable 28 having 1 ° C. and thermal conductivity (kcal / mh ° C.) of 8.76 is 309 ° C., and the inner surface D of the iron shell 225.
Is 226 ° C., and the temperature of the cooling jacket surface E is 212
° C, the temperature of the inner surface F of the heat insulating material 27 is 209 ° C, and even if the thickness of the innermost castable layer 29 is reduced to about 1/3, the temperature of the cooling jacket 6 is maintained at about 210 ° C.
The heat transfer effect of the inner layer castables 28 of the system works, so that the slag is self-coated, and the iron shell 25 is sufficiently protected. That is, the temperature of the inner surface B1 of the innermost castable 29 whose thickness has been reduced to about 1/3 is 1277.
℃, the temperature of the inner surface C1 of the inner layer castable 28 is 493.
° C, the temperature of the inner surface D1 of the iron shell 25 is 256 ° C, and the temperature of the cooling jacket surface E1 is 217 ° C, and the maximum thickness reduction position is secured in the innermost castable 29.

According to the present invention, as described above, the innermost castable 2
9 is a castable Al ₂ O ₃ . Preferably, 1
0-80% by weight Cr ₂ O ₃ —Al ₂ O ₃ based castable. In particular, in the side trunk portion and the furnace top dome portion of the combustion chamber 7, the innermost layer castable 29 in which Cr2O3 is usually 10 to 30% by weight, preferably about 15% by weight is constructed in terms of slag wear resistance. preferable.

Further, in the refractory support portion 30 at the lower portion of the combustion chamber 7, the furnace wall forms a different diameter portion, the cooling effect of the cooling jacket 6 cannot be expected, and the wearability due to the erosion of the molten slag flowing down is reduced. Since it is high, from the viewpoint of slag wear resistance, a precast 31 of 10 to 80% by weight of Cr ₂ O ₃ —Al ₂ O ₃ , preferably 20 to 40% by weight of Cr ₂ O ₃ , more preferably 30% by weight is more preferable.
Build with 1 A brick state may be used instead of the precast 31. This Cr2O3 is, for example, 20% by weight.
In the following, the slag wear resistance is not sufficient. For example, if it is 40% by weight or more, it becomes expensive and disadvantageous in terms of economy.

Further, in the high-temperature gasifier according to the present invention, as shown in FIGS. 2 and 5, at least one cooling coil 3 is provided near the throat portion 8 below the combustion chamber 7.
2 is provided. That is, the cooling coil 32 is castably embedded in the lower part of the combustion chamber 7 so as to surround the narrowed portion, that is, the throat portion 8. Cooling coil 32 is 2
In the case of more than one, each cooling coil 32 is provided independently,
Water pipes 33 for supplying cooling water are provided on the outer peripheral side, respectively, and are led out of the furnace.

Further, a cooling support 34 for an annular pipe made of a carbon steel plate is provided in a state continuous with the iron plate supporting the bottom of the refractory support portion 30 and surrounding the throat portion 8. That is, the cooling support 34, which is located below the cooling coil and supports the refractory support portion 30, has a slightly flat cross section and is formed in a ring-shaped cooling pipe having a large cooling water flow rate. ,
A greater cooling effect is provided by flowing the cooling water.

The cooling water supplied to the cooling coil 32 and the cooling support 34 is supplied at 40 to 60 ° C. and is discharged as water, unlike the cooling jacket 6, so that the refractory support 30 The castables are allowed to cool sufficiently. The effect of arranging the cooling support 34 together with the cooling coil 32 as described above on this refractory support portion 30, which has a different diameter portion at the lower portion of the combustion chamber 7 and has no conventional cooling medium, as described above, is great. There is something. By forming metal fins outside the cooling coil 32 and inside the furnace of the cooling support 34, the thermal conductivity can be further improved, and the castability can be further improved.

[0030]

According to the present invention, an oxygen inlet is provided at the furnace top so that diluted oxygen gas is blown from the furnace top.
The furnace top can be used as a partial combustion reaction zone, and the temperature of the combustion chamber is stabilized and the thermal efficiency is improved. Further, according to the present invention, the inner layer of the refractory furnace wall of the high temperature gasifier combustion chamber is made of an Al ₂ O ₃ system, particularly 10
８０80% by weight Cr ₂ O ₃ —Al ₂ O ₃ based castable and high thermal conductivity SiC castable with a two-layer castable structure, making use of the cooling effect of the exterior cooling jacket and self-coating with slag Is used early, and the effect of improving the durability of the furnace wall is achieved. Furthermore, an innermost layer castable the side trunk portion and the furnace top dome portion of the combustion chamber, in particular, since it is configured with 10 to 30 _{wt% Cr 2 O 3 -Al 2 O} 3 based castable, anti slag wear in these locations This has the effect of improving the durability and improving the durability of the furnace wall. And
According to the present invention in which the cooling support in contact with the refractory support portion is provided in a state surrounding the throat portion at the lower portion of the combustion chamber so that water can be actively cooled, the cooling effect at the location is enhanced, and the durability of the furnace body is increased. The effect of improving is produced. Further, the refractory support portion at the lower part of the combustion chamber where the cooling effect of the cooling jacket of the furnace wall is difficult to use is set to 10 to 80.
Wt%, preferably 20 to 40 wt% Cr ₂ O ₃ -A
Since it is made of l ₂ O ₃ castable, the slag wear resistance in the refractory support portion is improved, and the durability of the furnace body is improved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a main part of a gasification treatment apparatus of the present invention.

FIG. 2 is a longitudinal sectional view showing a combustion chamber portion of the high temperature gasifier in FIG.

FIG. 3 is a schematic sectional view showing a refractory structure of the high temperature gasifier in FIG.

FIG. 4 is a partial sectional view showing a temperature distribution in the refractory structure of the high temperature gasifier of FIG.

FIG. 5 is a partial sectional view showing a lower structure of a combustion chamber of the high temperature gasifier in FIG.

[Description of Signs] 1 Low-temperature gasifier 2 High-temperature gasifier 3 Gas washing tower 4 Quantitative supply device 5 Gas transport duct 6 Cooling jacket 7 Combustion chamber 8 Throat section 9 Quench chamber 10 Gas inlet 11 Furnace top 12 Downcomer 13 Injection weir 14 Lock hopper 15 Exhaust gas port 16 Venturi scrubber 17 Gas-liquid mixture cyclone section 18 Shelf step 19 Central pipe 20 Sheave type tray 21 Impact plate type tray 22 Demister 23 Oxygen inlet 24 Furnace oxygen inlet 25 Iron shell 26 Iron cover 27 Insulation material 28 Inner layer castable 29 Innermost layer castable 30 Refractory support part 31 Precast 32 Cooling coil 33 Water pipe 34 Cooling support

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C10K 1/02 C10K 1/02 1/10 1/10 F23G 5/027 ZAB F23G 5/027 ZABZ 5/44 ZAB 5/44 ZABZ F23J 15/04 F23J 15/00 D

Claims (11)

[Claims] 1. A low temperature gasifier for primary gasification of organic waste at low temperature, and a high temperature gasifier for secondary gasification of gas from the low temperature gasifier in a high temperature combustion chamber. A waste gasification treatment device comprising a gas cleaning tower for removing and cleaning the secondary gas, wherein an oxygen inlet for blowing a mixed gas obtained by mixing a diluent gas by a non-reactive gas with oxygen gas into the combustion chamber is provided. A waste gasification treatment apparatus provided at the top of the high temperature gasification furnace. 2. The combustion chamber has an outer shell covered with a cooling jacket and a SiC-based inner castable and an Al shell.
₂ O ₃ based gas treatment apparatus according to claim 1 waste wherein it has furnished with two layers of the innermost layer castables for. 3. The innermost layer castable is 10-80 weights.
Amount% Cr_TwoO_Three-Al _TwoO_ThreeIt is special that the system is castable.
The waste gasifier according to claim 2, characterized in that: 4. The innermost layer castable in the side trunk portion and the furnace top dome portion of the combustion chamber is 10 to 30% by weight C
Gas treatment apparatus as waste according to claim 1, characterized in that a r ₂ O ₃ -Al ₂ O ₃ system castable. 5. A low temperature gasifier for primary gasification of organic waste at a low temperature, and a high temperature gasifier for secondary gasification of gas from the low temperature gasifier in a high temperature combustion chamber. A waste gasification treatment apparatus comprising a gas cleaning tower for removing and cleaning the secondary gas, wherein the high-temperature gasification furnace is connected to a quenching chamber for cooling a generated gas through a throat below a combustion chamber. A gasification treatment apparatus for wastes, wherein a cooling support is provided in contact with a refractory support portion at a lower portion of the combustion chamber and surrounding the throat portion to allow a cooling medium to flow. 6. A gasification process of the waste according to claim 5, characterized in that the formation of the refractory support portion of the combustion chamber bottom with 10 to 80 _{wt% Cr 2 O 3 -Al 2 O} 3 based castable apparatus. 7. A gasification process of the waste according to claim 5, characterized in that the formation of the refractory support portion of the combustion chamber bottom 20 to 40 _{wt% Cr 2 O 3 -Al 2 O} 3 based castable apparatus. 8. A low-temperature gasifier for primary gasification of organic waste at a low temperature, a high-temperature gasifier for secondary gasification of gas from the low-temperature gasifier at a high temperature, A waste gasification treatment apparatus comprising a gas cleaning tower for removing and cleaning gas, wherein the high-temperature gasification furnace is connected to a quenching chamber for cooling generated gas through a throat portion at a lower part of a combustion chamber, In the high-temperature gasification furnace, a shell of a furnace wall outer shell is covered with a cooling jacket, and a lower portion in the cooling jacket is equally divided in a longitudinal direction into a plurality of sections to form a division jacket, and the division jacket is cooled. A header pipe for supplying a medium is provided, and a branch pipe of the header pipe is connected to each partition jacket via an orifice.By providing a differential pressure across each of the orifices, the cooling medium is supplied to the partition jacket. Equal A gasification treatment device for waste, wherein the gasification treatment device has a structure capable of supply. 9. A low-temperature gasifier for primary gasification of organic waste at low temperature, a high-temperature gasifier for secondary gasification of primary gas from said low-temperature gasifier at high temperature, A waste gasification treatment apparatus comprising: a gas cleaning tower for removing and cleaning a secondary gas, wherein the gas cleaning tower has a lower part in which a gas-liquid mixture cyclone for introducing a gas stream to be cleaned discharged from the high temperature gasification furnace. A gasification treatment apparatus for wastes, comprising: a two-stage gas cleaning device, in which a shelving tray and a collision plate-type tray are provided at the upper part thereof. 10. The shelving step includes a sheave type tray and a collision plate type tray incorporated in each of two stages, and is arranged in the order of the sheave type tray and the collision plate type tray from the upstream side of the gas flow to be cleaned. The waste gasification treatment apparatus according to claim 9, wherein: 11. The waste gasification apparatus according to claim 9, wherein a venturi scrubber is incorporated as a pretreatment apparatus for the gas cleaning tower.