JPH0545638B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooled jet burner for use in a spouted bed powder solid fuel gasifier.

[Conventional technology]

Coal has the largest reserves among fossil fuel resources and is attracting attention as an energy alternative to oil.

Coal is solid and inconvenient to handle, and it also contains ash, sulfur, nitrogen, etc. In order to use it effectively, it must be converted into a clean energy source through liquefaction, gasification, etc. desired. Coal gasification is currently attracting attention as a promising method for turning coal into a clean fuel. Among these, the coal gasification combined cycle system, which uses clean gas from coal for power generation, is attracting attention. One of the important technologies supporting the coal gasification combined cycle system is coal gasification technology, and as a gasifier for power generation, it has high gasification efficiency, operability and reliability that can meet the power demand,
Adaptability to a wide range of coal types is required. A spouted bed gasifier that reacts pulverized coal in an air stream is considered to be a promising gasifier that satisfies these conditions.

FIG. 12 is a schematic diagram of a gasifier using this jet tank gasifier. This device includes a coal supply system, a gasification agent supply system, a gasification furnace 30, and a dust collection system 34.
and desulfurization system 35, etc.

In the coal supply system, the powdered solid fuel 49 that has been crushed and classified by the crusher is supplied from the raw material conveyance line 47 to the normal pressure hopper 48, and then charged into the pressure hopper 22.
Thereafter, it is supplied to the supply hopper 23. Thereafter, after the powdered solid fuel 49 is quantified by the feeder 45, it is passed through the raw material transport line 25 using a carrier gas (nitrogen or inert gas) 24, and is supplied to the gasifier 30. On the way, there is a distributor 26 that can evenly distribute and supply the raw material to several jetting burners 27 .

In the gasification agent supply system, oxygen or air control valve 2
8. Flowing the gasification agent through the steam control valve 29, upper and lower gasification agent supply system lines 40 and 41,
Furthermore, the gasification furnace 30
supply to. The powdered solid fuel (coal, liquefied residue, etc.) 49 and the gasification agent are brought into contact at the outlet of the raw material injection burner 27 in the gasification furnace 30 .

The gasifier 30 has a structure lined with firebrick or the like. Because the temperature inside the furnace is over 1,400℃, the ash in the coal melts into a slag-like state. This slag falls freely, enters the slag hopper 32 filled with water, is rapidly cooled and solidified, and is extracted to the outside.

The gas generated from the gasifier 30 is transferred from the gasifier outlet line 33 to the dust collector 34 and the desulfurizer 35.
After removing the dust and dust containing incombustible carbon that are scattered together with the generated gas and the hydrogen sulfide in the generated gas, the gas is supplied as clean gas to a turbine or the like via a line 36.

Gasifier 30 installed in these reactors
As mentioned above, there is a supply system for powdered solid fuel (coal, liquefied residue, etc.) 49, and the gasifier 3
A raw material jetting burner 27 is always provided on the zero side.

This raw material injection burner 27 has a powder solid fuel 49
It is an important device that can generate gases rich in H2, CO, etc. by bringing the gasifier into contact with the gasifying agent inside and outside the burner and causing a reaction.

In this case, depending on the burner structure, the powder solid fuel may be near the outlet of the inner cylinder pipe (inside the powder solid fuel supply pipe),
It accumulates at the tip of the burner and becomes clogged, making continuous supply difficult. In addition, the temperature near the burner tip and the inner tube outlet increases due to the burner tip cooling structure and secondary heat radiation from inside the gasifier, and depending on the type of powdered solid fuel, the carbon content in the powdered solid fuel may increase. burner becomes solidified and deposits near the tip and the outlet of the inner tube, making it difficult to supply powdered solid fuel, making the cooling structure of the burner tip extremely important.

Conventionally, the following method is typical as a method for cooling the inside of a burner tip.

(1) A method of suppressing the temperature rise near the outlet of the inner tube by circulating a large amount of gas (nitrogen, inert gas, etc.) for transporting powdered solid fuel.

(2) A method of cooling the burner by circulating cooling water to the inside of the tip of the outer tube of the burner
180207, JP-A-60-36810), etc.

Method (1) has the advantage of preventing a temperature rise near the outlet of the inner tube even if the amount of cooling water is small, and method (2)
This method has the advantage of simplifying the structure.

[Problem to be solved by the invention]

When gasifying powdered solid fuel, it is necessary to reduce the amount of gas that transports the powdered solid fuel to the gasifier as much as possible. The reason for this is that inert gas (nitrogen or carbon dioxide, etc.) is generally used as the gas for transporting powdered solid fuel, and if the amount is large, it will suppress the temperature rise in the gasifier, which will affect the reaction surface. This is for the sake of influence. Therefore, when method (1) is used, there is a problem in that the temperature rise in the furnace is suppressed, the reaction rate is slowed, and the efficiency is reduced.
Furthermore, since the flow velocity within the inner tube increases, there is a problem in that wear near the outlet increases.

On the other hand, in method (2), the structure is simple, but because the cooling water does not come into contact with the outer wall near the outlet of the inner cylinder tube, the tip of the burner and the inner cylinder are subject to strong side radiation heat from the gasifier. The cooling capacity near the outlet of the pipe is reduced, and especially in internal mixing burners where powdered solid fuel and gasifying agent come into contact with each other inside the burner and generate high heat, it is conceivable that the pipe can be cooled only to a certain temperature. This has no effect on raw materials such as coal, but for raw materials that burn at low temperatures such as liquefaction residue, the raw materials burn at the tip of the inner tube (inside the powder solid fuel supply tube), solidify, and It is expected that the material will accumulate, resulting in an inability to supply the raw material.

An object of the present invention is to provide a cooling type jet burner that has less wear near the burner tip and can effectively prevent a temperature rise near the burner tip.

[Means to solve the problem]

The above purpose is to overlap multiple cylindrical tubes with different diameters on the same axis, and use the innermost inner tube as a central flow path for supplying powdered solid fuel and its carrier gas, and The space between the cylindrical tubes is configured as a flow path for circulating cooling water and a flow path for supplying the gasifying agent, and the cooling water flows at high speed onto the outer wall near the tip of the innermost inner cylindrical tube and the inner wall of the burner tip. This is achieved by arranging a flow path such that the

[Effect]

Cooling water is caused to flow at high speed into the raw material jetting nozzle installed at the tip of the burner and into the flow passage provided at the outer wall at the tip of the inner tube. This will increase the furnace temperature to 1400
Even at high temperatures of ℃ or higher, the temperature rise at the burner tip and inside the inner tube is suppressed, making it possible to continuously supply any type of powdered solid fuel.

〔Example〕

FIG. 1 is a sectional view of the tip of an embodiment of the cooling type jet burner according to the present invention, and FIG.
FIG. 3 is a radial cross-sectional view of the figure. Also, Figure 3 shows the first
4 is a schematic configuration diagram of a gasification furnace to which the burner shown in the figure is applied, and FIG. 4 is a sectional view taken along line AA in FIG. 3.

First, the gasifier shown in FIGS. 3 and 4 will be explained.

In FIG. 3, the gasifier 41 has a spouted bed type gasifier structure, and the inside is lined with a refractory material such as firebrick, and includes a slag cooling section 44, a gasification reaction section 31, and a produced gas distribution section. It consists of 46 pieces.

The burner 27 according to the present invention is arranged tangentially to the inner wall of the lower part of the gasifier reactor 31, as shown in FIG. 4, so that a swirling flow is formed in the gasifier.
Books are installed.

Each of these burners 27 has a cooling water inlet line 4.
2, an outlet line 43, a gasifying agent supply line (oxygen or air) 40 and a coal branch pipe line 39 are connected. Since the inside of the gasifier 41 reaches a high temperature of 1400°C or more, a slag cooling section 4 filled with water is used.
4, the slag is allowed to fall freely, rapidly solidified and recovered.

Next, the detailed structure of the burner 27 is shown in FIGS. 1 and 2.
This will be explained according to the diagram.

In FIG. 1, the burner 27 includes an outer tube (or cooling tube) 9, a gasifying agent supply tube (oxygen, air, and water vapor) 15, and an inner tube (powdered solid fuel supply tube) 1.
6. It consists of a cooling water supply pipe 17. The entire burner 27 has a quadruple tube structure, and the inside of the burner is cooled by cooling water 3 and 4 passing through cooling water supply flow passages 6 and 7.

The powdered solid fuel 1 passes through an inner cylinder pipe (powdered solid fuel supply pipe) 16 having a central flow path 8 and is ejected from the powdered solid fuel supply pipe outlet 14 .

The gasifying agent (oxygen, air, and water vapor) 2 passes through the flow path 5 in the gasifying agent supply pipe 15 and reaches a predetermined flow velocity in the flow path 10 in the raw material jetting nozzle 11.
The gasifying agent is ejected from the gasifying agent ejection port 13. These 13 jet holes are arranged in 8 directions in the circumferential direction as shown in the cross-sectional view of
Each hole has the same diameter and is opened at an angle at a certain angle from the center with respect to the inner cylinder pipe (powdered solid fuel supply pipe) 16.

The burner 27 of this embodiment is an external mixing type burner in which the powdered solid fuel 1 and the gasifying agent (oxygen, air, and water vapor) 2 come into contact at the burner outlet. The outer cylindrical tube tip 19 has a partially tapered structure to reduce the area of the tip that receives side radiation heat from the gasifier.

The cooling water circulation system at the tip of the burner will be described in detail below.

The cooling water 3 passes through the cooling water supply flow path 7 of the cooling water supply pipe 17 and reaches the raw material jetting nozzle 1 at the tip of the burner.
1, passes through the outer wall cooling water passage 12 near the outlet of the inner tube, cools the outer wall near the outlet of the inner tube, and then flows through the inner wall of the burner tip and the tapered inner wall cooling water passage 18 into the outer tube 9. The cooling water flows through the cooling water return passage 6 and is returned from the burner cooling water line to the existing device cooling water return line.

FIG. 5 is a sectional view of the tip of the second embodiment of the burner 27, and FIG. 6 is a radial sectional view of FIG. 5. 7 is a sectional view of the tip of the burner 27 according to a third embodiment, and FIG. 8 is a radial sectional view of FIG. 7. Furthermore, FIG. 9 is a sectional view of the tip of the burner 27 according to a fourth embodiment, and FIG. 10 is a radial sectional view of FIG.
In both cases, by changing the burner cooling water supply pipe 17 to the outside of the inner cylinder pipe 16 and installing the gasifying agent flow passage 5 outside the cooling water supply pipe 17, the inside near the tip of the inner cylinder pipe is This is an attempt to suppress the temperature rise, and has the same effect as the embodiment shown in FIG.

Figure 11 is a graph showing the influence of the cooling water flow rate on the internal temperature of the burner tip. As shown in the figure, the temperature inside the tip gradually decreases until the cooling water flow rate reaches 10 m/s. Not much has changed since then. From this, it can be seen that temperature rise can be effectively suppressed by setting the flow velocity in the inner wall flow passage at the burner tip to 10 m/s or more.

〔Effect of the invention〕

As explained above, according to the present invention, it becomes possible to reduce wear near the burner tip and effectively suppress the temperature rise near the burner tip and the inner tube outlet, and as a result, It has the effect of continuously supplying any kind of powdered solid fuel.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the tip of a first embodiment of the cooling type jet burner according to the present invention, Fig. 2 is a radial cross-sectional view of Fig. 1, and Fig. 3 is a gasification using the burner of the present invention. A schematic diagram of the furnace, Figure 4 is A- in Figure 3.
A sectional view, FIG. 5 is a sectional view of the tip of a second embodiment of the cooling type jet burner according to the present invention, FIG. 6 is a radial sectional view of FIG. 5, and FIG. 7 is a cooling type jet burner according to the present invention. FIG. 8 is a radial cross-sectional view of FIG. 7, and FIG. 9 is a front end sectional view of a third embodiment of the cooling type jet burner according to the present invention. 10 is a radial cross-sectional view of FIG. 9, FIG. 11 is a graph showing the relationship between cooling water flow rate and burner tip cooling water temperature, and FIG. 12 is a schematic configuration of a spouted bed gasifier. It is a diagram. 1...Powdered solid fuel, 2...Gasifying agent, 3...
Cooling water (supply), 4...Cooling water (return), 5...Gasifying agent, 6...Cooling water return flow path, 7...Cooling water supply flow path, 8...Center flow path, 9... Outer tube, 1
0... Raw material ejection nozzle internal flow passage, 11... Raw material ejection nozzle, 12... Inner cylinder pipe, 13... Gasifier outlet, 14... Powdered solid fuel outlet, 15... Gasifier supply pipe , 16...Inner cylinder pipe, 17...Cooling water supply pipe, 18...Tapered inner wall cooling water flow passage, 19
... Burner tip, 22 ... Pressure hopper, 23 ...
... Supply hopper, 24 ... Carrier gas, 25 ... Raw material transport line, 26 ... Distributor, 27 ... Raw material jet burner, 28 ... Gasifying agent control valve, 29 ... Steam control valve, 30 ... Jet flow Bed gasifier, 31... gasifier reaction section, 32... slag hopper, 33...
Gasifier outlet line, 34... Dust collection system, 35...
Desulfurization system, 36... Line, 37... Slag line, 38... Upper branch pipe line, 39... Lower branch pipe line, 40... Lower gasifier line, 41
... Upper gasifier line, 42 ... Cooling water inlet line, 43 ... Cooling water outlet line, 44 ... Water packed bed, 45 ... Feeder, 46 ... Gas generation distribution section, 47 ... Raw material conveyance line , 48... Ordinary pressure hopper, 49... Powdered solid fuel.

Claims (1)

[Claims] 1. A plurality of circular tubes with different diameters are superimposed on the same axis, and the innermost inner tube is a central flow path for supplying powdered solid fuel and its carrier gas, and the outer cylindrical tube is The space between the inner cylinder and the cylindrical tubes is configured as a flow path for circulating cooling water and a flow path for supplying the gasifying agent, and the cooling is provided on the outer wall near the tip of the innermost inner tube and the inner wall of the burner tip. A cooling type jet burner characterized by having a flow path that allows water to come into contact with it at high speed. 2. The cooling type jet burner according to claim 1, wherein the flow velocity of the cooling water flowing through the outer wall near the tip of the inner tube and the inner wall of the burner tip is 10 m/s or more. 3. The cooling type jet burner according to claim 1, wherein the outermost cylindrical tube has a partially tapered tip. 4. The cooling type jet burner according to any one of claims 1 to 3, wherein the powdered solid fuel and the gasifying agent come into contact after the outlet of the burner tip.