Combustion type harmful substance removing apparatus

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COMBUSTION TYPE HARMFUL combustion assisting gas nozzle for injecting a gas for SUBSTANCE REMOVING APPARATUS assisting combustion of a fuel gas formed to Surround the raw gas combustion assisting gas nozzle, and a fuel gas

TECHNICAL FIELD nozzle for injecting the fuel gas.

Incidentally, either the fuel gas combustion assisting gas

The present invention relates to a combustion type detoxi nozzle or the fuel gas nozzle may be located inside the other. fying apparatus, more particularly to a gas treating apparatus According to this constitution, Since the fuel gas combus for detoxifying toxic components Such as toxic gases, com tion assisting gas and the fuel gas are injected from different bustible gases and corrosive gases which are contained in nozzles respectively, flash-back can be prevented from raw gases Such as exhaust gases to be exhausted from occurring at the burner using a simple structure, and a Systems for producing Semiconductors or LCDS by allowing combustion detoxifying treatment of an exhaust gas can be Such components to burn or undergo pyrolysis. carried out Safely in a stable State. Since gases containing combustible or combustion Further, according to the present invention, Since the assisting toxic components are exhausted as exhaust gases burner is attached to the combustion chamber via a pre from Systems for producing Semiconductors or LCDS, these 15 combustion chamber having a capacity which is Smaller than exhaust gases should be Subjected to treatments for remov that of the combustion chamber, burning or pyrolysis of the ing Such toxic components (detoxifying treatment) before toxic components contained in the raw gas can be carried out they are exhausted. A combustion type detoxifying appara efficiently.

tus is known as an apparatus for carrying out Such detoxi Further, according to the present invention, Since the fying treatment of exhaust gases. combustion assisting gas is injected from the fuel gas This combustion type detoxifying apparatus carries out a combustion

Same as or assisting gas nozzle at a flow rate which is the higher than the flow rate of the fuel gas to be detoxifying treatment by allowing various kinds of toxic injected from the fuel gas nozzle, combustion of the mixture components contained in an exhaust gas to burn or undergo of these two gases can be carried out more efficiently to form pyrolysis using a burner provided in a combustion chamber, flames which envelope flames formed at the center by and a multi-wall pipe type burner consisting of nozzles for 25 combustion of toxic components, thus enhancing the effect injecting an exhaust gas, a combustion assisting gas, etc., of the detoxification treatment.

which are arranged concentrically, is usually employed as Further, according to the present invention, Since the tips the burner. of the raw gas nozzle, liftgas nozzle and raw gas combustion AS Such a multi-wall pipe type burner, there is employed assisting gas nozzle of the burner attached to the combustion a quadruple-wall pipe type burner consisting of an exhaust chamber via the pre-combustion chamber protrude beyond gas nozzle for injecting the exhaust gas, which is located at the tips of the fuel gas combustion assisting gas nozzle and the center, a lift gas nozzle for injecting a lift gas for lifting fuel gas nozzle, the fuel gas and the fuel gas combustion flames to be formed at the nozzle tip, which is arranged to assisting gas are mixed fully in the Space defined between Surround the exhaust gas nozzle, an exhaust gas combustion the inner circumferential wall of the pre-combustion cham assisting gas nozzle for injecting a gas for assisting com 35 ber and the protrusion of the burner. Accordingly, the burner bustion of combustible components in the exhaust gas, forms stable flames even if the flow rate of the raw gas which is arranged to Surround the lift gas nozzle, and a fluctuates, and powders formed during combustion do not combustion nozzle for injecting a mixed gas of a fuel gas deposit on the inner circumferential wall of the pre and a combustion assisting gas, which is arranged to Sur combustion chamber. Thus, the raw gas can be treated Safely round the exhaust gas combustion assisting gas nozzle. 40 in a stable State, and the frequency of maintenance Service

However, a problem in this quadruple-wall pipe type can be reduced to improve the operation rate of the appa ratuS.

burner is that flames of the burner can flashback, since a fuel gas and a combustion assisting gas which are to be injected Further, according to the present invention, the tip of the from the combustion nozzle are mixed at an appropriate rate 45 fuel gas combustion assisting gas nozzle and that of the fuel beforehand, and the resulting mixed gas is Supplied to the gas nozzle are formed to constitute an inverted V Shape Such burner. Accordingly, it is necessary to incorporate an equip that the nozzle holes of these nozzles may open on the walls ment and the like for preventing Such flash-back, which of the inverted V-shaped groove respectively to oppose each increases costs. other. Thus, the diffusion states of the fuel gas combustion Under Such circumstances, an objective of the present 50 assisting gas and fuel gas to be injected from these nozzles invention is to provide a combustion type detoxifying appa can be adjusted by Suitably Setting the angles of these walls ratus equipped with a multi-wall pipe type burner having a depending on the gas flow rates and the like, So that more Structure which can give a stable combustion State without preferred mixing and combustion States can be obtained. Further, according to the present invention, Since the causing flash-back.

combustion chamber has on the Outer circumference a gas 55 preheating passage for preheating at least a part of gases to

DISCLOSURE OF THE INVENTION

be introduced to the burner, the heat generated by combus

In the combustion type detoxifying apparatus according to tion can be utilized effectively by incorporating Such a the present invention, which carries out detoxification of a Simple structure into the apparatus, and thus reduction in the raw gas containing toxic components injected through a equipment installation Space and cost can be achieved. burner into a combustion chamber by allowing the toxic 60 Further, the combustion chamber can be cooled by the gas components to burn or undergo pyrolysis, the burner is a to be preheated, and also the amount of the fuel to be multi-wall pipe type burner having a raw gas nozzle for consumed can be lowered by the heat recovery. injecting the raw gas, a lift gas nozzle for injecting an inert gas formed to Surround the raw gas nozzle, a raw gas BRIEF DESCRIPTION OF THE DRAWINGS combustion assisting gas nozzle for injecting a gas for 65 FIG. 1 is a cross-sectional view showing a combustion assisting combustion of combustible components in the raw type detoxifying apparatus according to a first embodiment gas formed to Surround the lift gas nozzle, a fuel gas of the present invention;

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FIG. 2 is a croSS-Sectional view showing a burner employ An igniting pilot burner 16 is attached to the wall of the able in the combustion type detoxifying apparatus of the first combustion chamber 1 at an upper position So as to penetrate embodiment; the outer barrel 11 and the inner barrel 12. The pilot burner FIG. 3 is a cross-sectional view showing a nozzle portion a16mixed is of the conventional type having a Sparking plug, and gas of a fuel and a combustion assisting gas, e.g., of the burner shown in FIG. 2; propane gas and air, is ignited with the Sparking plug to be FIG. 4 is a cross-sectional view showing another nozzle burned and to light up a fuel gas injected from the burner 3 portion of the burner employable in the combustion type with the resulting flame.

detoxifying apparatus of the first embodiment; The combustion chamber 1 has a lower opening 17 which FIG. 5 is a cross-sectional view showing a combustion is connected to an exhaust gas treating System (not shown) type detoxifying apparatus according to a Second embodi via a chamber 19 provided with spray nozzles 18 for ment of the present invention; Spraying a coolant for cooling the combustion gas. FIG. 6 is a cross-sectional view showing another nozzle The lower part in the pre-combustion chamber 2 commu portion of the burner employable in the combustion type nicates with the upper part in the combustion chamber 1. The detoxifying apparatus of the Second embodiment; 15 capacity of the pre-combustion chamber 2 is designed to be

Smaller than that of the combustion chamber 1.

FIG. 7 is a cross-sectional view showing another nozzle The burner 3 is formed to have a quintuple-wall pipe portion of the burner employable in the combustion type structure consisting of five pipes 31a,31b,31c,31d,31e detoxifying apparatus of the Second embodiment; which are arranged concentrically. The inner Space of the FIG. 8 is a cross-sectional view showing a combustion center pipe 31a and the Spaces between every adjacent two type detoxifying apparatus according to a third embodiment pipes respectively constitute gas channels. The pipes have at of the present invention; the tips a raw gas nozzle 32a for injecting a raw gas FIG. 9 is a cross-sectional view showing a combustion containing toxic components, a lift gas nozzle 32b for type detoxifying apparatus according to a fourth embodi injecting an inert gas employed as a lift gas, a raw gas ment of the present invention; combustion assisting gas nozzle 32c for injecting a gas for 25 assisting combustion of combustible components in the raw

FIG. 10 is a cross-sectional view showing another gas, a fuel gas combustion assisting gas nozzle 32d for embodiment of the pre-combustion chamber; and injecting a gas for assisting combustion of a fuel gas, and a FIG. 11 is a cross-sectional view showing another fuel gas nozzle 32e for injecting the fuel gas, respectively embodiment of the pre-combustion chamber. which are arranged outward in this order.

BEST MODE FOR CARRYING OUT THE

An annular nozzle member 33 Serving also as a Spacer is

INVENTION

fitted in the fuel gas combustion assisting gas nozzle 32d and the fuel gas nozzle 32e. The fuel gas combustion assisting

Embodiments of the present invention will be described gas and fuel gas are injected through nozzle holes. 33a,33b, respectively formed in the nozzle member 33. An annular below more specifically referring to the drawings. Slit or a multiplicity of holes arranged in the circumferential First, a combustion type detoxifying apparatus according 35 direction constitute each nozzle hole 33a(33b). to a first embodiment of the present invention shown in A blocking member 34a is fitted to the proximal end FIGS. 1 to 3 will be described.

portion of the center pipe 31a, while annular blocking

This combustion type detoxifying apparatus contains a members 34b,34c,34d,34e, for blocking the rear ends of the combustion chamber 1, a pre-combustion chamber 2 located 40 gas channels formed between the pipes and for retaining the at the top of the combustion chamber 1 and a burner 3 pipes at predetermined intervals, are fitted to the proximal attached to the pre-combustion chamber 2. end portions of the pipes 31b,31c,31d,31e respectively. The combustion chamber 1 has a double-wall structure Spacers 35 for maintaining the intervals may be fitted as containing a cylindrical Outer barrel 11 made of an ordinary necessary at the middle portions of the pipes. metallic material and the like and a cylindrical inner barrel 45 The pipe 31a has at the proximal end Side a raw gas 12 made of a porous material which are arranged concen Supply pipe 37a for Supplying a raw gas to a raw gas channel trically. 36a; the pipe 31b has at the proximal end side a lift gas The outer barrel 11 is provided with a fluid nozzle 14 for Supply pipe 37b for Supplying an inert gas to a lift gas introducing a pressure fluid Such as compressed air into a channel 36b; the pipe 31c has at the proximal end side a raw space 13 defined between the outer barrel 11 and the inner 50 gas combustion assisting gas Supply pipe 37c for Supplying barrel 12. A baffle plate 15 is disposed on the inner surface a raw gas combustion assisting gas to a raw gas combustion of the outer barrel 11 so as to face the tip of the fluid nozzle assisting gas Supply channel 36c; the pipe 31d has at the 14. The baffle plate 15 is disposed so as to diffuse the proximal end a fuel gas combustion assisting gas Supply pressure fluid to be introduced through the fluid nozzle 14 pipe 37d for Supplying a fuel gas combustion assisting gas throughout the Space 13. 55 to a fuel gas combustion assisting gas channel 36d, and the The combustion chamber 1 has a constitution Such that pipe 31e has at the proximal end Side a fuel gas Supply pipe powderS may be prevented from depositing on the inner 37e for Supplying a fuel gas to a fuel gas channel 36e. The Surface of the inner barrel 12 by introducing the pressure pipe 31a also has at the proximal end Side an auxiliary fuel fluid through the fluid nozzle 14 into the space 13 and supply pipe 37f. The auxiliary fuel Supply pipe 37f is allowing the pressure fluid to burst inward through the pores 60 incorporated, as necessary, So as to Supply a combustible gas of the porous material constituting the inner barrel 12. Such as hydrogen into the raw gas when the raw gas contains Accordingly, even if powdery Solid oxides are formed Small amounts of combustible components.

during combustion treatment of a raw gas or if powders are The burner 3 has on its barrel a flange 38 which is used carried on the raw gas, Such powders are not deposited on when the burner 3 is attached to the pre-combustion cham the inner Surface of the inner barrel 12 to interfere with the 65 ber 2. The burner 3 is attached via the pre-combustion combustion treatment, and thus the combustion treatment chamber 2 to the central portion at the top of the combustion can be carried out in a stable State over an extended period. chamber 1.

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When a raw gas containing toxic components is Subjected posed at the top of the combustion chamber 1 and a burner as the raw gas to combustion detoxifying treatment in the 3 attached to the pre-combustion chamber 2. constituted detoxifying apparatus, the raw gas to be treated The combustion chamber 1 in this embodiment is the is injected from raw gas nozzle 32a, an insert gas Such as same as that shown in FIG. 1, except that the cylindrical nitrogen and argon is injected from the lift gas nozzle 32b, inner barrel made of a porous material, the fluid nozzle and an oxygen-containing gas Such as nitrogen and argon is the baffle plate are omitted.

injected from the raw gas combustion assisting gas nozzle Further, the pre-combustion chamber 2 in this embodi 32c, another oxygen-containing gas is injected from the raw ment is Surrounded by a cylindrical cooling jacket 21 to gas combustion assisting 32d, a fuel gas Such as propane gas which a coolant is distributed to cool the circumferential is injected from the fuel gas nozzle 32e, and a natural gas wall 22 of the pre-combustion chamber 2. and hydrogen are also injected, and the gases are ignited In the burner 3 of this embodiment, the tips of a raw gas with the flame of the pilot burner 16. nozzle 32a, a lift gas nozzle 32b and a raw gas combustion In this constitution, Since the burner 3 is designed Such assisting gas nozzle 32c protrude beyond the tips of a fuel that the fuel gas and the fuel gas combustion assisting gas gas combustion assisting gas nozzle 32d and a fuel gas may be injected through Separate nozzles, respectively, and 15 nozzle 32e. More specifically, the raw gas nozzle and the lift burned flash-back, which can occur, in the conventional gas nozzle of the burner shown in FIGS. 1 to 3 are extended, burner, when the fuel gas and the fuel gas combustion and a cylindrical part 51 is connected to the front end of the assisting gas are mixed before injection through the nozzle, nozzle member 33 to extend the raw gas combustion assist can be avoided, and there is no need to incorporate an ing gas. nozzle 32c. The outside diameter of the cylindrical equipment and the like for preventing Such flash-back, part 51 is the Same as the inside diameter of the fuel gas leading to a reduction in the equipment costs. Incidentally, combustion assisting gas nozzle 32d. Other constitutions of a similar flash-back preventing effect can be obtained even the burner 3 are the same as the counterparts of the burner when the positional relationship of Supplying and injecting shown in FIG. 4.

the fuel gas combustion assisting gas and the fuel gas is The length of protrusion of the raw gas nozzle 32a, lift gas reversed to locate the fuel gas nozzle inside and the fuel gas 25 nozzle 32b and raw gas combustion assisting gas nozzle 32c combustion assisting gas nozzle outside. is 5 mm or more, preferably 20 mm or more but is not so The fuel gas combustion assisting gas and the fuel gas much that they protrude from the pre-combustion chamber injected from the fuel gas combustion assisting gas nozzle 2.

32d and the fuel gas nozzle 32e respectively can be mixed This constitution of the burner 3 achieves Sufficient mix and burned efficiently by providing the pre-combustion ing of a fuel gas and a fuel gas combustion assisting gas in chamber 2. Particularly, mixing and burning of these two the space defined between the inner wall surface of the gases can be carried out more efficiently by injecting the fuel pre-combustion chamber 2 and the cylindrical part 51, So gas combustion assisting gas through the fuel gas combus that the burner forms stable flames, and powders occurring tion assisting gas nozzle 32d at a flow rate which is the same 35 during combustion do not deposit on the inner wall Surface or 3 to 10 times as high as that of the fuel gas to be injected of the pre-combustion chamber 2.

through the fuel gas nozzle 32e. Thus, the flames formed at Accordingly, a raw gas can be treated Safely in a stable the central portion by combustion of the toxic components State, and the frequency of maintenance Service can be are enveloped with the flames formed by combustion of the reduced to improve the operation rate of the apparatus. fuel gas and the fuel gas combustion assisting gas, So that the 40 While it is preferred to form an inverted V-shaped groove effect of the detoxifying treatment can be enhanced. 41 at the tips of the fuel gas combustion assisting gas nozzle Next, another embodiment of the burner to be employed 32d and fuel gas nozzle 32e, like in the burner shown in FIG. in the first combustion type detoxifying apparatus shown in 4, these nozzles may have flat nozzletips like in the burner FIG. 1 will be described referring to FIG. 4. shown in FIGS. 1 to 3.

In the burner 3 shown in FIG. 4, the nozzle hole of the fuel 45 Incidentally, in the burner shown in FIGS. 1 to 3 and those gas combustion assisting gas nozzle 32d and that of the fuel shown in FIGS. 4 and 5, the fuel gas nozzle 32e and the fuel gas nozzle 32e are located on the walls of an inverted gas channel 36e are located outside of the fuel gas combus V-shaped groove to oppose each other. More Specifically, the tion assisting gas nozzle 32d and the fuel gas combustion inverted V-shaped groove 41 is formed at the distal end face assisting gas channel 36d. However, there is no inconve of the nozzle member 33, and a nozzle hole 33a of the fuel 50 nience at all if the fuel gas nozzle 32e and the fuel gas gas combustion assisting gas nozzle 32d opens to the inner channel 36e are located inside the fuel gas combustion circumferential wall 42a of the groove 41, while a nozzle assisting gas nozzle 32d and the fuel gas combustion assist hole 33b of the fuel gas nozzle 32e opens to the outer ing gas channel 36d.

circumferential wall 42b of the groove 41. Constitutions of FIG. 6 shows a burner 3 in which the outside diameter D1 other parts of the burner are Substantially the same as those 55 of the cylindrical part 51 is slightly smaller than the inside of the counterparts in the burner shown in FIGS. 1 to 3. diameter D2 of the nozzle hole 33a for injecting the fuel gas Diffusion States of the fuel gas combustion assisting gas combustion assisting gas, whereas FIG. 7 shows a burner 3 and fuel gas injected from the nozzles 32d and 32e respec in which the outside diameter D1 is slightly greater than the tively can be adjusted by appropriately Setting the angles of inside diameter D2. Other constitutions of these burners are the walls 42a,42b depending on the gas flow rates etc., and 60 the same as the counterparts of the burner shown in FIG. 5. by providing more preferred mixing and combustion State. AS described above, by reducing or increasing Slightly the Next, a combustion type detoxifying apparatus according outside diameter D1 of the cylindrical part 51 relative to the to a Second embodiment of the present invention shown in inside diameter D2 of the nozzle hole 33a for injecting the FIG. 5 will be described. fuel gas combustion assisting gas, the cylindrical part 51 is This combustion type detoxifying apparatus, like that of 65 prevented from being burned by the flame of the burner and the first embodiment shown in FIG. 1, is provided with a becoming red hot when the fuel gas nozzle 32e is located combustion chamber 1, a pre-combustion chamber 2 dis outside of the fuel gas combustion assisting gas nozzle 32d.

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For example, in a burner having an outside diameter of 89 treatment can be carried out Securely by increasing the mm provided with a fuel gas combustion assisting gas combustion temperature, while fuel Saving is achieved. injecting nozzle hole 33a having an inside diameter D2 of 71 Further, since the outer barrel 11 and inner barrel 61 of the mm and a cylindrical part 51 having a protrusion length of combustion chamber 1 can be cooled with these gases, the 60 mm, the cylindrical part 51 can be prevented from exterior of the apparatus is prevented from becoming hot, becoming red hot by reducing the outside diameter D1 leading to increased Safety. In addition, Since the gas pre thereof within the range of 2 mm or increasing it within the heating passages are formed to Surround the combustion range of 1 mm relative to the inside diameter D2. chamber 1 integrally there with, the construction is inexpen Incidentally, in the burners shown in FIGS. 6 and 7, the Sive compared with a heat eXchanger which is installed tips of the fuel gas combustion assisting gas nozzle 32d and conventionally as an individual unit, and it requires Substan tially no extra installation Space.

fuel gas nozzle 32e may be flat like in the burner shown in Deposition of powderS Such as of Solid oxide occurring FIGS. 1 to 3. There is no inconvenience at all even in these during combustion treatment of the raw gas on the inner burners, if the fuel gas nozzle 32e is located inside the fuel circumferential Surface of the combustion chamber causes gas combustion assisting gas nozzle 32d. not only a narrowing of the combustion chamber which Next, a combustion type detoxifying apparatus according 15 lowers combustion efficiency, but also a drop in the heat to a third embodiment of the present invention shown in transfer efficiency which reduces preheating efficiency, etc. FIG. 8 will be described. However, Since powders are removed by Spraying air, water This combustion type detoxifying apparatus, like that of and the like Suitably from the powder-removing Spray the first embodiment shown in FIG. 1, is provided with a nozzle 64, an efficient combustion detoxifying treatment can combustion chamber 1, a pre-combustion chamber 2 dis be continued in a stable State over a long time. posed at the top of the combustion chamber 1 and a burner heat Meanwhile, in order to improve preheating efficiency, the 3 attached to the pre-combustion chamber 2. transfer area may be enlarged by providing fins and the The combustion chamber 1 of this embodiment is formed like on the outer Surface of the inner barrel 61. Further, the gas preheating passages may be formed by winding a pipe to have a double-wall Structure consisting of a cylindrical 25 spirally around the outer barrel 11, and the number of Such outer barrel 11 and a cylindrical inner barrel 61 which are passages may be Selected as desired.

arranged concentrically, with a Space Serving as a gas The powder-removing Spray nozzle 64 may be incorpo preheating passage 62 being defined between the outer rated only in those cases where powdery Solid oxides and the barrel 11 and the inner barrel 61. The outer barrel 11 and the like are deposited during the combustion treatment on the inner barrel 61 are formed employing an ordinary metallic inner circumferential Surface of the combustion chamber, material and the like. To the gas pre-heating passage 62 are and the fluid to be a sprayed may be liquid Such as water or connected a raw gas combustion assisting gas introducing a gas Such as air and nitrogen gas.

pipe 63 for introducing a raw gas combustion assisting gas FIGS. 10 and 11 show pre-combustion chambers of other into the gas preheating passage 62 and a raw gas combustion embodiments. In the pre-combustion chamber 2 shown in assisting gas Supply pipe 37c for Supplying the preheated 35 FIG. 10, the inner wall 23 is contracted at the tip; whereas raw gas combustion assisting gas to a raw gas combustion in the pre-combustion chamber 2 shown in FIG. 11, the inner assisting gas channel of the burner 3. The combustion wall 24 is expanded at the tip.

chamber 1 is provided on the wall thereof with a spray AS described above, the pre-combustion chamber can be nozzle 64 for removing powderS deposited on the inner formed to have a Suitable configuration depending on the surface of the inner barrel 61 which penetrates the outer 40 amounts and flow rates of various gases to be injected from barrel 11 and the inner barrel 61. the burner, the kinds of gases, the nozzle Shape, etc. Thus, Other constitutions of the combustion chamber 1 and the an optimum relationship can be Secured between flames to constitutions of the pre-combustion chamber 2 and burner 3 burner be formed by combustion of the fuel gas at the tip of the are Substantially the same as the counterparts shown in FIG. gas, further and flames to be formed by combustion of an exhaust 1. enhancing the detoxifying efficiency. 45 Furthermore, the length of the pre-combustion chamber can

FIG. 9 shows a combustion type detoxifying apparatus be set Suitably depending on the diameter of the burner, the according to a fourth embodiment of the present invention, amount and flow rate of each gas to be injected, etc. in which a partition 65 is disposed in the space defined However, if the length of the pre-combustion chamber is between the outer barrel 11 and the inner barrel 61 in the Smaller than /3 of the burner diameter, the effect of the combustion chamber 1 of the third embodiment shown in 50 pre-combustion chamber cannot be exhibited Sufficiently, FIG. 8 to define gas preheating passages 62a,62b. To the gas whereas if it is longer than twice the burner diameter, the preheating passage 62a are connected a raw gas introducing pre-combustion chamber no more Serves as the pre pipe 66 for introducing a raw gas to the preheating passage combustion chamber, Since it assumes a function as the 62a and a raw gas Supply pipe 37a for Supplying the combustion chamber.

preheated raw gas to the raw gas channel of the burner 3. To 55 AS described in the above embodiments, while it is the gas preheating passage 62b are connected a raw gas preferred, in the combustion type exhaust gas treating combustion assisting gas introducing pipe 63 and a raw gas apparatus, that the burner 3 is attached to the combustion combustion assisting gas Supply pipe 37c like in the third chamber 1 via the pre-combustion chamber 2, the burner 3 embodiment shown in FIG. 8. Other constitutions of the may be attached directly to the combustion chamber 1. combustion type detoxifying apparatus according to the 60 In the present invention, the configurations and structures fourth embodiment are Substantially the same as the coun of the combustion chambers and pre-combustion chambers terparts of the third embodiment. including attachments are not to be limited to the above AS described above, in the third and fourth embodiments, embodiments.

combustion of the raw gas can be accelerated by preheating TEST EXAMPLE 1.

the raw gas and the raw gas combustion assisting gas with 65 the heat generated by the combustion treatment before they A detoxifying treatment for removing Silane was carried are Supplied to the burner 3, and thus, the detoxifying out employing a combustion type detoxifying apparatus

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having the structure shown in FIGS. 1 to 3. The combustion Supplied to the raw gas channel 36a was within the range of chamber 1 had an outer barrel 11 made of a stainless steel 40 to 60 lit/min.

material and having an outside diameter of 200 mm, and an inner barrel 12 made of a sintered metal of Stainless Steel and TEST EXAMPLE 3 having an outside diameter of 150 mm, a thickness of 3 mm The same combustion type detoxifying apparatus as in and a nominal filtration accuracy of 100 um. The combus Test Example 2 was employed to Supply gases as follows: tion chamber 1 had a height of 300 mm. The burner 3 had nitrogen gas containing 3% of Silane to the raw gas channel an outside diameter of about 90 mm, and the length of the 36a at a rate of 150 lit/min, nitrogen gas to the lift gas portion of the pre-combustion chamber 2 protruding beyond the tip of the burner 3 was 55 mm. Incidentally, as the channel 36b at a rate of 10 lit/min; air to the raw gas pre-combustion chamber 2, one having a cooling jacket as combustion assisting gas channel 36c at a rate of 100 lit/min, shown in FIG. 5 was employed. air to the fuel gas combustion assisting gas channel 36d at a rate of 125 lit/min, and propane gas to the fuel gas channel

Gases were Supplied to the burner 3 as follows: nitrogen 36e at a rate of 5 lit/min, respectively, and the gases were gas (N) containing 3% of Silane (SiH) to the raw gas ignited using the pilot burner 16.

channel 36a at a rate of 150 lit/min: nitrogen gas (N) to the 15 When the inside of the combustion chamber 1 was lift gas channel 36b at a rate of 10 lit/min; air to the raw gas inspected after the apparatus was operated continuously combustion assisting gas channel 36c at a rate of 100 lit/min, under the above-described conditions for 24 hours, the air to the fuel gas combustion assisting gas channel 36d at powder generated during combustion of the Silane gas had a rate of 125 lit/min, and propane gas (LPG) to the fuel gas been deposited neither in the pre-combustion chamber 2 nor channel 36e at a rate of 5 lit/min, respectively. on the burner 3. Further, the Silane concentration in the gas To the pilot burner 16 was supplied a gas formed by exhausted mixing 1 lit/min of propane gas and 22 lit/min of air. To the stantly lessfrom the exhaust gas treating System was con than /10 of the threshold limit value 5 ppm space defined between the outer barrel 11 and the inner throughout the operation.

barrel 12 of the combustion chamber 1 was supplied com 25 AS a comparative example, when the procedures of Test pressed air having a pressure of 4 kg/cm2G from the fluid Example 3 were repeated using the apparatus employed in nozzle 14 at a rate of 165 lit/min.

When the apparatus was operated under the above were Test Example 2 and the burner 3 shown in FIG. 2, powders described conditions for 24 hours, no flash-back occurred.

deposited on the inner Surface of the pre-combustion chamber 2 to a maximum thickness of about 5 mm. The

Meanwhile, the Silane concentration in the gas exhausted powderS also were deposited Slightly on the fuel gas com from an exhaust gas treating System was constantly less than bustion assisting gas nozzle 32d of the burner 3. /10 of the threshold limit value 5 ppm throughout the operation. TEST EXAMPLE 4 TEST EXAMPLE 2 A detoxifying treatment for removing Silane was carried

A detoxifying treatment for removing Silane was carried out employing a combustion type detoxifying apparatus out employing a combustion type detoxifying apparatus having the structure shown in FIG. 8. The combustion having the structure shown in FIG. 5. The combustion chamber in this combustion type detoxifying apparatus had chamber 1 had an outer barrel 11 made of a stainless steel a double-wall Structure having a height of 400 mm, consist material and having an outside diameter of 150 mm and a 40 ing of a StainleSS Steel inner barrel 61 having an outside height of 300 mm. The burner 3 had an outside diameter of diameter of 165.2 mm and a stainless steel outer barrel 11 about 90 mm, and the length of protrusion of the raw gas having an outside diameter of 216.3 mm. Temperature nozzle 32a, lift gas nozzle 32b and raw gas combustion Sensors were provided in the gas preheating passage 62 and assisting gas nozzle 32c was 60 mm. The length of the at the lower opening 17, respectively. Air for burning Silane portion of the burner 3 in the pre-combustion chamber 2 45 was allowed to flow through the gas preheating passage 62. protruding beyond the tip of the fuel gas combustion assist Gases were Supplied to the burner 3 as follows: nitrogen ing gas nozzle 32d and fuel gas nozzle 32e was 80 mm. gas containing 3% of Silane from the raw gas Supply pipe Gases were Supplied to the burner 3 as follows: nitrogen 37a at a rate of 150 lit/min, nitrogen gas from the lift gas gas containing 3% of Silane to the raw gas channel 36a at a supply pipe 37b at a rate of 10 lit/min; air from the raw gas rate of 100 lit/min, nitrogen gas to the lift gas channel 36b 50 combustion assisting gas Supply pipe 37c and through the at a rate of 10 lit/min, air to the raw gas combustion assisting gas preheating passage 62 at a rate of 100 lit/min, air to the gas channel 36c at a rate of 100 lit/min; air to the fuel gas fuel gas combustion assisting gas Supply pipe 37d at a rate combustion assisting gas channel 36d at a rate of 125 lit/min, 125 lit/min, and propane gas (LPG) from the fuel gas Supply and propane gas to the fuel gas channel 36e at a rate of 5 pipe 37e at a rate of 5 lit/min, respectively, and the gases lit/min, respectively, and the gases were ignited using the 55 were ignited using the pilot burner 16. pilot burner 16. AS a result, the temperature of the gas at the lower Subsequently, when nitrogen gas was Supplied at random opening 17 of the combustion chamber was 730 C., and the within the range of 0 to 150 lit/min to the raw gas channel temperature in the gas preheating passage 62 was 370 C. 36a, the burner 3 constantly formed stable flames. Further, a powder of Silicon dioxide formed as a combustion Further, when combustion was carried out continuously 60 product of Silane was deposited on the inner Surface of the with nitrogen gas at a rate of 150 lit/min to the raw gas being inner barrel 61 when combustion treatment was continued. supplied channel 36a, the cylindrical part 51 of the burner 3 However, the powder was removed by injecting compressed did not become red hot. air intermittently from the spray nozzle 64 without affecting AS a comparative example, when the procedures of Test the combustion treatment, nor the preheating of air and Example 2 were repeated using the apparatus employed in 65 cooling of the inner barrel 61.

Test Example 2 and the burner 3 shown in FIG. 2, the burner AS a comparative example, a detoxifying treatment for 3 formed unstable flames when the flow rate of nitrogen gas removing Silane was carried out under the Same conditions

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as in Test Example 4, except that the combustion chamber 4. The combustion detoxifying apparatus according to consisted only of a Stainless Steel cylinder having an outside claim 1, wherein the combustion chamber has on an outer diameter of 165.2 mm and a height of 400 mm, and that air circumference a gas preheating passage for preheating at Serving as the raw gas combustion assisting gas was Sup least a part of gases to be introduced to the burner. plied directly to the burner. As a result, the temperature of 5 5. The combustion detoxifying apparatus according to the gas at the lower opening 17 of the combustion chamber claim 1, wherein tips of the raw gas nozzle, lift gas nozzle was 710 C., and the temperature of the circumferential wall and raw gas combustion assisting gas nozzle protrude of the combustion chamber was 400 C. beyond tips of the fuel gas combustion assisting gas nozzle We claim: and fuel gas nozzle.

1. A combustion detoxifying apparatus comprising: 6. The combustion detoxifying apparatus according to a combustion chamber, and claim 5, wherein the tip of the fuel gas combustion assisting a burner for injecting a raw gas containing toxic gas nozzle and the tip of the fuel gas nozzle are formed to components, an inert gas, a combustion assisting gas constitute an inverted V shape such that the nozzle holes of and a fuel gas into the combustion chamber; these nozzles open on the walls of the inverted V-shaped 15 groove respectively to oppose each other.

the burner being a multi-wall pipe burner having a raw gas 7. The combustion detoxifying apparatus according to nozzle for injecting the raw gas, a lift gas nozzle for claim 5, wherein the combustion chamber has on an outer injecting the inert gas formed to Surround the raw gas circumference a gas preheating passage for preheating at nozzle, a raw gas combustion assisting gas nozzle for least a part of gases to be introduced to the burner. injecting a gas for assisting combustion of combustible 8. A method of detoxifying a gas containing toxic com components in the raw gas formed to Surround the lift ponents in a combustion detoxifying apparatus having gas nozzle, a fuel gas combustion assisting gas nozzle for injecting a gas for assisting combustion of the fuel a combustion chamber; and gas formed to Surround the raw gas combustion assist a burner for injecting a raw gas containing toxic ing gas nozzle, and a fuel gas nozzle for injecting the 25 components, an inert gas, a combustion assisting gas fuel gas, and a fuel gas into the combustion chamber; wherein the multi-wall pipe burner is attached to the the burner being a multi-wall pipe burner having a first combustion chamber via a pre-combustion chamber nozzle, a Second nozzle formed to Surround the first having a capacity which is Smaller than that of the nozzle, a third nozzle formed to Surround the Second combustion chamber. nozzle, a fourth nozzle formed to Surround the third 2. The combustion detoxifying apparatus according to nozzle, and a fifth nozzle, claim 1, wherein the combustion assisting gas is injected comprising injecting into the combustion chamber a raw from the fuel gas combustion assisting gas nozzle at a flow gas containing toxic components from the first nozzle, rate which is the same as or higher than the flow rate of the an inert gas from the Second nozzle, a fuel gas from the fuel gas to be injected from the fuel gas nozzle. 35 fifth nozzle, a gas for assisting combustion of the raw 3. The combustion detoxifying apparatus according to gas from the third nozzle, and a gas for assisting claim 1, wherein a tip of the fuel gas combustion assisting combustion of the fuel gas from the fourth nozzle. gas nozzle and a tip of the fuel gas nozzle are formed to 9. The method according to claim 8, wherein an auxiliary constitute an inverted V shape such that the nozzle holes of combustible gas is Supplied with the raw gas. these nozzles open on the walls of the inverted V-shaped groove respectively to oppose each other. k k k k k