CN113046136A

CN113046136A - Novel water-cooled wall protective structure

Info

Publication number: CN113046136A
Application number: CN202110337314.0A
Authority: CN
Inventors: 不公告发明人
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-03-30
Filing date: 2021-03-30
Publication date: 2021-06-29

Abstract

The invention provides a novel water-cooled wall protection structure which is a double-layer protection structure formed by combining a fire-resistant layer and a slag chamber. The slag chamber is provided with slag in advance. The slag in the slag chamber and the slag generated by gasification reaction in the gasifier are filled in the slag chamber together in the operation process of the gasifier to form a reliable slag layer, and a slag film is formed on the side wall surface outside the slag chamber and facing the fire, so that reliable dynamic protection is provided for the water wall in the operation process of the gasifier. By adopting the double-layer protection structure, the problems of local overheating and slag tap blockage generated in the operation process of the gasification furnace can be solved, the long-period operation of the gasification furnace is facilitated, the service life of the gasification furnace is prolonged, and temperature reference can be provided for the operation of the gasification furnace, so that the operation of the gasification furnace is improved, and the double-layer protection structure has practical value for production operation.

Description

Novel water-cooled wall protective structure

Technical Field

The invention relates to a novel water-cooled wall protection structure, belongs to the field of water-cooled walls and heat exchangers, and particularly relates to a water-cooled wall of a gasification furnace.

Background

The coal pressure gasification technology is an important direction for clean utilization of coal, and the gasification furnace is a key device in the coal gasification technology. The gasification raw material and the gasifying agent react rapidly in the gasification furnace to generate the raw synthesis gas. In order to improve the carbon conversion rate, the gasification furnace needs to work in a high-temperature and high-pressure environment, and a water-cooled wall is mostly adopted as a protection device of a shell. In order to protect the water-cooled wall and realize the long-period operation of the gasification furnace, a refractory layer formed by high-temperature resistant materials is coated on the surface of the water-cooled wall for protection, and the refractory layer is protected by adopting a slag-resistant technology in the operation process of the gasification furnace, so that the stable operation of the gasification furnace is ensured.

The slag-resisting technology requires that the gasification furnace can operate stably in a certain temperature range. However, the gasifier has a complex structure and high operation difficulty, the temperature in the gasifier is difficult to measure and control, and the situation that the fluctuation range of the operating temperature of the gasifier exceeds the expected range is wide, so that the situation that the protection effect is poor by using a slag-resistant technology occurs occasionally, the refractory layer is damaged, even the water wall tube is burnt, and the long-period stable operation of the gasifier is endangered.

The slag-resistant technology can cause the flow rate of liquid slag flowing down the wall surface to change when circulating from low temperature to high temperature, especially when the working condition of the gasification furnace is unstable, and after the gasification furnace works in the low temperature range for a long time, the liquid slag flow rate at the slag discharging port can be obviously increased when the gasification furnace is rapidly heated to high temperature, thereby causing the risk of overheating and burning of the chilling ring of the slag discharging port, blockage of the slag discharging port and furnace shutdown.

Because high-temperature, high-pressure and multi-phase flow heat transfer and a complex gasification reaction process exist in the gasification furnace, the temperature distribution in the furnace has obvious difference in different areas, so that the wall thickness of the gasification furnace is obviously different, partial wall surface generates local overheating due to thinner slag layer, the service life of a refractory layer of the wall surface of the local area in the gasification furnace is shorter, and especially when the furnace condition is unstable, partial wall surface can generate serious overheating, so that the refractory layer is burnt and even a water cooling wall is burnt, and the safe operation of the gasification furnace is seriously threatened.

The slag-resistant technology is a method capable of better controlling the furnace condition under the condition that the temperature of the gasification furnace cannot be accurately controlled, and a set of more suitable gasification furnace operation parameters are frequently found out by comparing according to experience and repeatedly adjusting for a long time in actual production, so that the operation difficulty of the gasification furnace is increased.

Disclosure of Invention

The invention aims to provide a novel water-cooled wall protection structure, which solves the problems of local overheating of a water-cooled wall and blockage of a slag discharging opening in the operation process of a gasification furnace so as to prolong the operation period of the gasification furnace. Therefore, the method for protecting the water-cooled wall by presetting the slag layer in the slag chamber is provided, the reliable protection is provided for the water-cooled wall, the long-period operation of the gasification furnace is realized, the operation temperature of the gasification furnace can be purposefully regulated and controlled by taking the ash melting point of the preset slag in the slag chamber as a reference, and the operation of the gasification furnace is improved.

The purpose of the invention is realized as follows: a novel water-cooled wall protection structure is provided with a fire-resistant layer and a slag chamber double-layer protection structure.

In a specific embodiment, the refractory layer is attached directly to the waterwall.

In a specific embodiment, the slag chamber is attached to the inner side of the refractory layer and is arranged along the axial direction of the water-cooled wall; an annular inner cavity with an opening is formed among the slag chamber, the adjacent slag chamber and the refractory layer along the circumferential direction; the annular inner cavity is pre-filled with slag; the slag chamber is provided with a slag guide claw at the edge of the fire side; the fire-facing side wall surface of the slag chamber is provided with spinous processes.

In a specific embodiment, the slag chamber can also form an annular inner chamber with an opening with an adjacent slag chamber without the aid of a refractory layer.

In a particular embodiment, the refractory material used for the refractory layer may also be replaced by slag.

In one embodiment, the slag chamber may be formed of a plurality of annular slag chamber segments due to thermal expansion and contraction effects, design and manufacturing requirements, and the like. The specific number of annular slag chamber segments is determined by the specific specification of the gasifier and other factors, so the segments of the annular slag chamber are not shown in the drawings of the present invention.

In a specific embodiment, when the gasification furnace is in operation, liquid molten slag continuously splashes and adheres to the slag guide claw, the side wall surface of the slag chamber facing the fire and the spinous process, and molten slag flows into the slag chamber along the slag guide claw and the slag chamber, so that the molten slag in the slag chamber is filled, overflows and flows downwards, and a slag film is formed outside the slag chamber. Because the slag continuously flows into the slag chamber along the slag guide claw and the slag chamber to the fire side wall surface and then continuously overflows, a continuous slag film is formed on the fire side wall surface. Because the slag chamber is filled with the slag, a continuous slag film is arranged outside the wall of the slag chamber, and the slag chamber can keep a stable and reliable slag layer no matter how the temperature fluctuates, so that the water-cooled wall is protected, and the water-cooled wall is prevented from being burnt due to local overheating. The flowing in and overflowing of the slag are repeated, so that the reliable dynamic protection of the water-cooled wall in the operation process of the gasification furnace is realized.

The invention has the following advantages:

the novel water-cooled wall protection structure provided by the invention initiates a protection mode of pre-arranging the molten slag in the slag chamber, can effectively solve the problems that the operation cycle of the gasification furnace is shortened due to damage of a fire-resistant layer and even burning of the water-cooled wall caused by local overheating when the furnace condition of the gasification furnace is unstable, and realizes long-cycle operation of the gasification furnace. And can provide temperature reference for the operation of the gasification furnace, improve the operation of the gasification furnace and have practical value for production operation.

Drawings

FIG. 1 is a schematic diagram of a water wall protection structure according to an embodiment of the present invention.

FIG. 2 is a three-dimensional partially enlarged schematic view of a slag chamber in the water-cooled wall protective structure according to the embodiment of the invention.

Fig. 3 is another enlarged partial three-dimensional schematic view of a slag chamber in the water-cooled wall protective structure of the embodiment of the invention, which is used for showing the situation that the slag chamber and an adjacent slag chamber form an annular inner cavity with an opening without a refractory layer.

Detailed Description

The drawings are provided to illustrate aspects and features of the present invention, but not to limit the scope of the present invention. In particular, the sectional shape of the slag chamber can be various, the combination mode of the slag chamber and the refractory layer can also have various forms, and the combination mode can be adopted according to the design and manufacture requirements, so that the combination mode cannot be listed, and the combination mode cannot be understood as the limitation of the protection scope due to the difference from the attached drawings. Any equivalent forms or modifications of the implementation of the present application having the characteristics as set forth in the claims are intended to be covered by the present application.

Examples

A novel water-cooled wall protection structure is shown in figure 1 and comprises a water-cooled wall 1, a fire-resistant layer 2, a slag chamber 3, slag 4, slag guide claws 5 and spinous processes 6.

The refractory layer 2 is directly attached to the water-cooled wall 1, and the slag chamber 3 is arranged on the inner side of the refractory layer 2. The slag chamber 3, the adjacent slag chamber 3 and the refractory layer 2 extend along the circumferential direction to form an annular inner cavity with an opening. The annular inner cavity is pre-provided with slag 4. The slag chamber 3 is provided with a slag guide claw 5 at the edge towards the fire side, the wall surface towards the fire side of the slag chamber is provided with a spinous process 6, and the spinous process 6 is a bulge.

In a particular arrangement, as shown in figure 3, the slag chamber may extend circumferentially with the adjacent slag chamber without the aid of a refractory layer to form an annular inner chamber having an opening.

As shown in fig. 2, the slag guide claw 5 is formed by notching the edge of the slag chamber toward the fire side, and is a part of the edge of the slag chamber. In a specific scheme, the notch is eliminated, and the edge of the slag chamber facing the fire side becomes the slag guiding claw 5.

The working process of the protective structure of the invention is explained in detail below with reference to the accompanying drawings.

When the gasification furnace operates, the gasification raw material and the gasification agent react rapidly in the gasification furnace, and liquid slag generated in the reaction process splashes and adheres to the fire side wall surfaces of the slag guide claw 5 and the slag chamber 3, and then flows into the slag chamber 3. The slag 4 preset in the slag chamber 3 is filled with the slag 3 together with the slag which continuously flows in, and overflows from the opening of the slag chamber 3, and a layer of slag film is formed on the side wall surface of the slag chamber 3 facing to the fire. Because the gasification reaction is continuously carried out, the molten slag continuously flows into the slag chamber 3 and overflows from the slag chamber 3, so that the slag chamber 3 is filled with the molten slag all the time, a stable slag layer is formed, and reliable protection is provided for a water-cooled wall. The overflowed slag and the liquid slag splashed on the fire side wall surface of the slag chamber 3 and the spinous process 6 flow on the fire side wall surface of the slag chamber 3 together to form a continuous slag film. No matter how the temperature of the gasification furnace fluctuates, the slag chamber is filled with the slag all the time, so that the slag chamber and the refractory layer can provide reliable protection for the water-cooled wall. Meanwhile, due to the existence of the slag film on the surface of the slag chamber 3 facing the fire side, the slag chamber 3 can be effectively protected, so that the slag chamber 3 can reliably work, the water-cooled wall of the gasification furnace can be reliably protected during operation, and the service life of the gasification furnace can be prolonged.

Claims

1. The utility model provides a novel water-cooling wall protective structure, characterized by: the double-layer protective structure is composed of a fire-resistant layer and a slag chamber.

2. The waterwall protection structure of claim 1, wherein: the fire-resistant layer is directly attached to the water-cooled wall.

3. The waterwall protection structure of claim 1, wherein:

the slag chamber is attached to the inner side of the fire-resistant layer and is axially arranged along the water-cooled wall;

the slag chamber, the adjacent slag chamber and the refractory layer extend along the circumferential direction to form an annular inner cavity with an opening;

the annular inner cavity is pre-filled with slag;

the slag chamber is provided with a slag guide claw at the edge of the fire side, and the wall surface of the fire side of the slag chamber is provided with a spinous process.

4. The waterwall protection structure of claim 1, wherein: the slag chamber may consist of one or several annular slag chamber segments.

5. The waterwall protection structure of claim 1, wherein: the sectional shape of the slag chamber can be various, and the combination mode of the slag chamber and the refractory layer can also be various, and the drawing of the invention is only one example.

6. The waterwall protection structure of claim 1, wherein: in a specific scheme, the fire-resistant layer can be replaced by a slag chamber to form a double slag chamber structure.

7. The waterwall protection structure of claim 1, wherein: the water-cooled wall is protected by adopting a mode of presetting molten slag in the slag chamber.