JPH076254U - Coal gasifier combustor - Google Patents

Abstract

(57) [Abstract] [Purpose] Molten slag (13) solidifies in the slag hole (14) in the case of coal with a high melting point (1300 to 1500 ° C) in the combustor (1) of a spouted bed coal gasification furnace. And prevent it from becoming difficult to discharge. [Structure] The nozzle (1) is installed above the combustor burner (7).
6) is provided, and the air (18) is jetted downward from the horizontal to lower the position of the high temperature combustion zone (12) to prevent the molten slag (13) from solidifying, and stable slag discharge. Do.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to improvement of a combustor for a jet bed coal gasification furnace.

[0002]

[Prior art]

 4 is a vertical side view showing an example of a conventional spout bed coal gasification furnace, FIG. 5 is a cross-sectional plan view taken along the line VV of FIG. 4, and FIG. 6 is a sectional view taken along line VI-VI of FIG.

The jet bed coal gasification furnace is composed of a combustion section 1 and a carbonization gasification section (hereinafter referred to as a gasification section) 2, and a refractory material 3 is lined inside the furnace. The combustion unit 1 is generally called a combustor, and has a plurality of combustor burners 7 for injecting fuel carried by air flow, and a slag hole 14 for discharging slag in which ash content in coal is melted. In this combustion section (combustor) 1, pulverized coal and char are burned under high temperature and high load to generate high temperature combustion gas. In the gasification section, the high-temperature combustion gas is used as a heat source to dry-coal coal and gasify it.

A mixed gas 5a of pulverized coal and air which has been conveyed by air flow from the pulverized coal supply equipment 4a through a mixed gas conveying pipe 6a is introduced into the combustor 1 from a primary air nozzle pipe 8 of a combustor burner 7. It On the other hand, the secondary air 9 required for combustion is introduced into the combustor 1 from the air supply equipment 19 through the secondary air carrier pipe 10 and the secondary air nozzle pipe 11 of the combustor burner 7. The mixed gas 5a introduced into the combustor 1 is combusted by the secondary air 9 to form a high temperature combustion zone 12 near the same level as the combustor burner 7. By this high-temperature combustion, the ash content in the coal is melted to form the molten slag 13, which adheres to the wall surface of the combustor 1 by the jet flow. Further, the molten slag 13 fluidized by receiving the radiant heat flows down and accumulates toward the slag hole 14, and is discharged.

Further, the high temperature combustion gas generated in the combustor 1 flows into the gasification section 2 and is supplied from the pulverized coal supply equipment 4b through the mixed gas carrier pipe 6b and the gasification burner 15 to the pulverized coal. Coal in the mixed gas 5b of air and air is dry-distilled, gasified, and exhausted.

[0006]

[Problems to be solved by the device]

 In such a coal gasification furnace, in the case of coal with a low ash melting point (1200 to 1300 ° C), slag fluidization in the 14th slag hole is good and steady discharge is performed. However, in the case of coal with a high melting point (1300 to 1500 ° C), even if it is melted on the wall surface, it may become difficult to discharge from the slag hole 14 due to solidification at the slag hole 14 and solidification. . The quality of such discharge of molten slag from the combustor greatly affects the performance of the gasification furnace.

If the combustor burner 7 is provided immediately above the slag hole 14 and the high temperature combustion zone 12 is formed at that height, solidification of the slag can be prevented. However, if it is fluidized too much, the slag hole 14 and the refractory material 3 are eroded by the molten slag 13.

[0008]

[Means for Solving the Problems]

 In order to solve the above-mentioned conventional problems, the present invention comprises a plurality of burners for injecting fuel and secondary air carried by air flow, and a slag hole for discharging molten slag in which ash in coal is melted out of the system. In a combustor of a spouted bed coal gasification furnace, a combustor is proposed in which an air nozzle is provided above the burner and the jet nozzle is arranged to be inclined downward from the horizontal.

[0009]

[Action]

 When air is jetted from the air nozzle that is inclined downward, the jet flow of the combustor burner is pushed by the jet flow of the air nozzle and becomes a downward jet flow. Therefore, the high-temperature combustion area in the combustor shifts downward, and the solidification of molten slag in the slag hole can be prevented. Also, by changing the injection amount from the air nozzle, the position (height) of the high temperature combustion area can be freely changed, and stable slag discharge can be achieved even with coal having different ash melting points.

[0010]

【Example】

 1 is a vertical side view showing an embodiment of the present invention, FIG. 2 is a cross-sectional plan view taken along the line II-II of FIG. 1, and FIG. In these figures, the same parts as those of the conventional one described with reference to FIGS. 4 to 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

The present embodiment is different from the conventional example in that the current-transforming nozzle 16 is provided immediately above the combustor burner 7. The current change nozzle 16 is connected to the secondary air carrying pipe 10 of the combustor burner 7 via a valve 17 so that a part of the secondary air 9 can be injected. In addition, the tip of the current-transforming nozzle 16 is inclined downward with respect to the horizontal direction, and the jetting end further widens the current-flowing jet 18 of the current-transforming nozzle. It was a cross section.

When the discharge of the molten slag 13 is unstable or difficult during the operation of the gasification furnace, the valve 17 is opened and a part of the secondary air 9 is injected from the current change nozzle 16. Since the jet end of the variable-flow nozzle 16 is inclined downward, the variable-flow nozzle jet flow 18 collides with the mixed gas 5 and the secondary air 9 injected from the combustor burner 7, and the jet flow is directed downward. Push down. Since the tip of the current-changing nozzle 16 is a nozzle that is long in the circumferential direction, even if the jet flow of the combustor burner 7 spreads, its pushing-down effect is great. Thus, the high temperature combustion region 12 moves downward as compared to when the current change nozzle 16 is not used, the heat radiation to the slag hole 14 portion increases, and the solidification of the molten slag 13 is prevented.

[0013]

[Effect of device]

 In the present invention, the position (height) of the high temperature combustion region can be freely changed by providing the air nozzle above the combustor burner and injecting the air downward from the horizontal. Therefore, the molten slag can be discharged stably by changing the height of the slag according to the type of coal and the state of slag discharge to prevent the molten slag from solidifying and maintain its fluidity.

In addition, since the high temperature combustion region moves downward, the combustion gas in the combustor stays longer, promoting complete combustion and improving the slag formation rate (amount of discharged slag / amount of input coal × ash content). Can be achieved.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view taken along the line II-II of FIG.

FIG. 3 is a view taken along the line III-III in FIG.

FIG. 4 is a vertical sectional side view showing an example of a conventional spouted bed coal gasification furnace.

5 is a cross-sectional plan view taken along the line VV of FIG.

6 is a sectional view taken along line VI-VI of FIG.

[Explanation of Codes] 1 Combustor 2 Gasification part 3 Refractory material 4a, 4b Pulverized coal supply equipment 5a, 5b Mixed gas 6a, 6b Mixed gas carrier pipe 7 Combustor burner 8 Primary air nozzle pipe 9 Secondary air 10 Secondary air Carrier pipe 11 Secondary air nozzle pipe 12 High temperature combustion zone 13 Molten slag 14 Slag hole 15 Gasification burner 16 Current change nozzle 17 Valve 18 Current change nozzle Jet flow 19 Air supply equipment

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location C10J 3/72 J (72) Inventor Yasuo Hayata 5-717-1, Fukahori-cho, Nagasaki-shi Mitsubishi Heavy Industries Nagasaki Research Institute Co., Ltd. (72) Creator Tomonori Koyama 5-717-1 Fukahori-cho, Nagasaki City Mitsubishi Heavy Industries, Ltd. Nagasaki Research Institute Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A combustor for a jet-bed coal gasification furnace, comprising a plurality of burners for injecting fuel and secondary air carried by air flow and a slag hole for discharging molten slag in which ash content in coal is melted out of the system. In the above, the combustor for a coal gasification furnace is characterized in that an air nozzle is provided above the burner, the air nozzle being disposed so as to be inclined downward from the horizontal.