JP2003106960A - Gasification gas sampling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device avoiding blocking of a gas sampling port when sampling high temperature gas under existence of slag. SOLUTION: The gasification gas sampling device is characterized by that, in a gasifying device installed with a gasifying furnace, a gas exhaust tube in an upper part of the gasifying furnace, and a produced gas sampling probe in the gas exhaust tube, a plane of an opening of the sampling port of the gas sampling probe has an angle of -45 deg. to 45 deg. to a horizontal direction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a gasification technique using coal or coal pyrolysis residue as a gasification raw material.

[0002]

2. Description of the Related Art To deal with the problem of global warming, the development and practical application of new energy, the shift to low carbon dioxide generation energy, the improvement of the nuclear power ratio, the efficient and rational use of existing primary energy, and the unused energy It is being promoted by using energy and waste energy. The gasification process in which coal and the residue (char) obtained by heating and pyrolyzing coal are gasified with oxygen and steam, and carbon monoxide and hydrogen are the main products, is an efficient and rational use of existing primary energy. It is a technology that belongs to the category of utilization and leads to improvement of handling property and versatility and simplification of equipment by making solid energy into a fluid and simplifying a complicated molecular structure. Among these, this technology is
The present invention is a mainstream jet bed gasification, which relates to gasification of a gasification raw material having ash content.
It is represented by the coal gasification equipment of Japanese Patent No. 84. Gasification is performed at 1400 to 1700 ° C., which is higher than the melting point of ash, and the ash is separated and discharged as liquid slag.

[0003]

The temperature inside the gasification furnace is high, and the ash content in the raw material is liquefied to form slag. Normally, it is moved to the lower part of the furnace by gravity and discharged, but part of it is carried along with the gasification gas and scattered, or it moves along the wall surface under the influence of the gas flow and moves to the latter stage of the gas flow. These slags rapidly deteriorate in fluidity when the gas temperature decreases, and easily solidify. Most of them occur after the exhaust gas exhaust pipe from the gasification furnace where the radiant heat received from the gas is reduced. Gasification furnaces usually have ports in the furnace and gas passages for pressure detection and gas sampling, and these ports are easily blocked by slag. In particular, coal, which is a raw material having a higher ash content or a higher melting point ash than raw materials such as LNG and heavy oil, has many sampling problems and has been a major operational problem. Although a measure to avoid it was taken by gas sampling in the low temperature process in the latter part, the actual high temperature part (gasification furnace) operation cannot be grasped because the gas equilibrium constant changes due to temperature changes and the gas composition changes. Therefore, it was necessary to perform sampling in the presence of slag while keeping the temperature as high as possible, quenching (while maintaining the gas composition), and performing analysis. Further, the gas sampling port has a drawback that it is particularly apt to be clogged because the slag is likely to enter deep inside the gas sampling port and is likely to be cooled compared to a detection port for detecting pressure without gas flow. Generally, there is a backwashing mechanism with nitrogen etc., and slag is blown off by high-pressure gas, but there are many problems such as the gas gives an error to the generated gas analysis value and there are times when the gas analysis value cannot be grasped. .

In the gasification process, the gasification gas component at a high temperature is a particularly important index, and there is a need to minimize the influence of the blockage of the sampling port on the operation. Fluctuations in gas components have a large effect on the subsequent steps such as combustion and chemical synthesis as changes in the calorific value of the produced gas, and the reliability of the thermometer deteriorates especially in the presence of slag (the protective tube was kept for a long time). It is necessary to correct the temperature information from the gas component information to stabilize the gasifier, and it is essential to accurately grasp the gas composition. Therefore, it is an object of the present invention to provide a device that prevents the gas sampling port from being blocked when sampling gas from a high temperature gas in the presence of slag.

[0005]

Means for Solving the Problems The present invention is an effective means for solving the above problems. 1) A gasification furnace and a gas exhaust pipe are installed above the gasification furnace. A gasification apparatus provided with a generated gas sampling probe, wherein the surface of the opening of the sampling port of the gas sampling probe has an angle of −45 ° to 45 ° with respect to the horizontal direction. Sampling device, 2) The gasification gas sampling device according to 1), wherein the gas sampling probe has a structure having a cooling function, and can be inserted downward at an angle of 30 ° to 60 ° with respect to the horizontal. , 3) A device having a cooling function is installed outside the gas sampling probe, and further 30 ° to 60 ° to the horizontal.
The gasification gas sampling device according to 1) or 2), which can be inserted downward at an angle of
Consists of.

[0006]

FIG. 4 shows an example of gas sampling according to a conventional method. In this example, high temperature gasified gas at around 1500 ° C. is sampled. The gas flow shows an upward flow with an emphasis on slag separation, but the idea regarding the sampling part is the same for both downward and horizontal gas flows. For gas sampling, sampling at the time when the gas components are stable is desirable, and sampling is performed at a place where mixing is considered to have been sufficiently performed. Here, it refers to the gas discharge tube 3. The generated gas 2 generated in the gasification furnace 1 is a gas exhaust pipe 3
And flow to the subsequent step 4 such as gas purification. For example, cooling equipment, heat recovery equipment, thermal decomposition equipment, and the like. The generated gas 2 is supplied to the external equipment 7 having a sampling device and an analysis device from a sampling port 6 which is a generic name of a portion at the tip of the sampling probe 5 by the self-pressure of the reactor or suction by an external equipment 7 such as a pump. Move out. The sampling probe needs to be cooled in order to protect it from the high-temperature generated gas 2 containing slag, but in the case of the example in FIG. 4, the sampling probe 5 itself does not have a cooling function and is cooled by a double-tube type. It is cooled by a water cooling pipe 8 having a function. The slag blockage mentioned as the problem to be solved by the present invention is likely to occur at the sampling port 6. That is, the slag existing in the flow of the high-temperature generated gas 2 and on the inner wall surface of the gas discharge tube 3 exists in a liquid state due to the ambient temperature of the melting point or higher, but is cooled by water when sucked from the sampling port 6. The heat is removed by the tube 8 and the sampling probe 5 to lower the temperature to below the melting point and solidify. Since the solidified slag is constantly removed from heat, it does not remelt and accumulates a certain amount by the heat balance between the radiant heat of the produced gas 2, the sensible heat, the slag's sensible heat, and the heat removal of the water cooling pipe 8 and the sampling probe 5. As a result, the adhered slag 9 is formed. The attached shape is a shape in which the vicinity of the sampling port 6 is raised. Generally, the diameter of the sampling probe should be as narrow as possible in consideration of heat loss, usually φ50 mm.
When the slag is present, the linear flow velocity becomes faster as the diameter becomes smaller, and the risk of blockage due to being drawn increases. On the other hand, since the design concept of increasing the diameter by deteriorating the thermal efficiency of the equipment is not usually taken, the gasification furnace with slag has a problem of blockage.

FIG. 1 shows an embodiment to which the present invention is applied.
The gasification temperature is 1500 ° C to 1600 ° C, and the coal pyrolysis residue (char) is gasified with oxygen and steam. The ash content in the char is about 10% by mass, and molten ash content (slag) exists in the gasification furnace 1. In this example, the surfaces of the generated gas 2 and the opening of the sampling port 6 are 0 ° with respect to the horizontal. The expression of the angle presented here is representative including the case where the surface of the opening is not a flat surface. For example, in the example of FIG. 1, even if the surface is concave, convex or uneven, the gas exhaust pipe 3 The angle between the horizontal line and the line connecting the farthest end from the end of the sampling port closest to the wall surface is 0 °. Further, as shown in FIG. 2, the definition of ± is + when the angle 10 between the sampling port 6 and the wall surface of the gas discharge tube 3 is obtuse and-when the angle is acute. As the gas discharge cylinder, because it is caster-tight, usually a cylindrical one is used,
The gas exhaust pipe may be, for example, a gas exhaust pipe.

Compared with the conventional method, the same applies until the slag adheres to the surface of the opening and is cooled and solidified.
The solidified adhered slag 9 is peeled off by its own weight and easily drops. In the example of FIG. 4, the surface of the opening is 90 ° with respect to the horizontal.
Since the surface of the opening is continuous to the inner wall of the gas discharge tube 3, it is more firmly fixed than in FIG. 1 (the wall material is usually made of refractory, which is similar to the slag property). Therefore, it is easy to get used to it) and is difficult to peel off. The contact surface angle for obtaining this effect is −45 ° to + 45 °, and from experience, it is desirably −15 ° to + 15 °. +4
When it was larger than 5 °, the peeling effect was small and the degree of blockage increased. When the angle is smaller than −45 °, the space formed by the sampling port 6 and the wall surface of the gas discharge tube 3 becomes narrower, so that the slag is easily stored. FIG. 2 shows an example (a) in which the surface angle of the opening with the gas is −45 ° and +45.
An example (b) in which the angle is 0 is shown. In both cases, the amount of adhesion was smaller than in the case of + 90 °, and the blockage could be avoided, but the amount of adhesion was larger than in the case of 0 ° in FIG. The range of + 15 ° to −15 ° is the actual angle that does not require the blocking prevention treatment.

In the example of FIG. 1, the sampling probe 5 and the water cooling pipe 8 are installed so as to form an angle of 45 ° downward with respect to the horizontal. This aims to prevent the slag from being drawn into the sampling probe (gravity is applied due to the inclination, making it difficult to draw in slag with a large specific gravity), and to return the slag drawn into the probe to the system. . The slag drawn into the flow of the sampling gas stays at an angle close to horizontal and is stacked, so that the slag is clogged even if there is no adhesive force.
An appropriate insertion angle for exerting such an effect of preventing slag pull-in is an angle of 30 ° or more and 60 ° or less with respect to the horizontal. If it is less than 30 °, it has been found that the drawn-in slag is difficult to return (stagnation in the probe). Also, considering the construction problem of refractory bricks, casters, and the possibility of falling, 60 ° It has been found that a larger angle makes the wall thickness on the gas exhaust tube side too thin and cannot maintain the shape. The sampling probe is described in FIG.
As a device having a cooling function outside the sampling probe, use a water cooling pipe or the like, or use a structure in which the sampling probe has a cooling function, such as a water cooling double pipe structure capable of cooling the sampling probe itself. You can

FIG. 3 shows a comparison of gas concentration measurement situations.
As an example of the analyzed gas, a change with time of CO (carbon monoxide) is shown. In the normal gas sampling shown in FIG. 4, the clogging occurred frequently, and the gas data was collected while constantly performing backwashing with high-pressure nitrogen and manual slag removal.
The gas sampling value could not be collected after that because it was completely blocked in about 0 hours. On the other hand, when the present method of FIG. 1 was used, only a short backwash with nitrogen once every 30 minutes (same interval as the backwash with pressure gauge) provided stable gas data during the test for more than 200 hours. I was able to collect it. The test was completed in 210 hours, but the open inspection after the test did not reveal any blockage due to adhered slag or the like.

[0011]

EFFECTS OF THE INVENTION By appropriately setting the angle of the contact surface of the gas sampling port with the gas with respect to the horizontal, it is possible to promote the separation of slag and enable the gas sampling which can suppress the clogging of the slag. Furthermore, by installing the gas sampling probe at an appropriate insertion angle, it is possible to perform operation without blockage for a long time even in backwashing processing similar to the detection port of a pressure gauge without gas suction.

[Brief description of drawings]

FIG. 1 is a gas sampling probe of the present invention.

FIG. 2 Sampling port shape.

FIG. 3 Comparison of gas concentration measurement conditions.

FIG. 4 Conventional gas sampling.

[Explanation of symbols]

1: Gasification furnace 2: Product gas 3: Gas exhaust tube 4: Subsequent process 5: Sampling probe 6: Sampling port 7: External equipment 8: Water cooling tube 9: Attached slag 10: Angle between sampling port 6 and wall surface of gas discharge tube 3

   ─────────────────────────────────────────────────── ─── Continued front page    (71) Applicant 000004123             Nippon Steel Tube Co., Ltd.             1-2 1-2 Marunouchi, Chiyoda-ku, Tokyo (71) Applicant 000001199             Kobe Steel Co., Ltd.             2-10-10 Wakihama-cho, Chuo-ku, Kobe-shi, Hyogo (72) Inventor Shigeru Hashimoto             20-1 Shintomi, Futtsu City Nippon Steel Co., Ltd.             Inside the surgical development headquarters (72) Inventor Masami Onoda             20-1 Shintomi, Futtsu City Nippon Steel Co., Ltd.             Inside the surgical development headquarters (72) Inventor Komizu-ryu Hiroyuki             20-1 Shintomi, Futtsu City Nippon Steel Co., Ltd.             Inside the surgical development headquarters (72) Inventor Jun Fujikawa             46-59 Nakahara, Tobata-ku, Kitakyushu City Made in Japan             Engineering Co., Ltd. F term (reference) 2G052 AA00 AB12 AC23 AD02 AD23                       AD42 BA03 BA14 CA02 CA04                       CA11 EB04 JA20

Claims (3)

[Claims] 1. A gasification apparatus comprising a gasification furnace, a gas discharge tube installed above the gasification furnace, and a generated gas sampling probe installed in the gas discharge tube, the opening of a sampling port of the gas sampling probe. A gasification gas sampling device, wherein the surface has an angle of −45 ° to 45 ° with respect to the horizontal direction. 2. The gas sampling probe is provided with a structure having a cooling function, and further 30 ° to 60 ° with respect to the horizontal.
The gasification gas sampling apparatus according to claim 1, wherein the gasification gas sampling apparatus can be inserted downward at an angle of. 3. A device having a cooling function is installed outside the gas sampling probe, and further 30 ° with respect to the horizontal.
The gasification gas sampling device according to claim 1 or 2, wherein the gasification gas sampling device can be inserted downward at an angle of 60 °.