WO2025241663A1

WO2025241663A1 - Gasifier burner for dry-feed pulverized coal gasification processes

Info

Publication number: WO2025241663A1
Application number: PCT/CN2025/081986
Authority: WO
Inventors: Chengming GAO; Xiaofei GAO; Junpeng Liu; Qiang QU; Xiaoming Quan
Original assignee: Air Products and Chemicals Inc
Current assignee: Air Products and Chemicals Inc
Priority date: 2024-05-24
Filing date: 2025-03-12
Publication date: 2025-11-27
Anticipated expiration: 2026-11-24
Also published as: CN121006235A

Abstract

The present invention provides a gasifier burner for a dry-feed pulverized coal gasification process, comprising: a first central pipe having a central axis; a first annular pipe concentrically surrounding the first central pipe, the first annular pipe comprising a plurality of first outlets at a head end of the gasifier burner; a second annular pipe concentrically surrounding the first annular pipe, the second annular pipe comprising a plurality of second outlets at the head end of the gasifier burner; and a third annular pipe concentrically surrounding the second annular pipe to form an outer wall of the gasifier burner, a head end of the first central pipe being fluidly connected to a head end of the third annular pipe by means of a connecting channel; characterized in that the first central pipe is for entry of cooling water and in that the third annular pipe is for leaving of the cooling water, so that cooling water flows along an inner side of a head end wall and an outer wall of the gasifier burner.

Description

GASIFIER BURNER FOR DRY-FEED PULVERIZED COAL GASIFICATION PROCESSES

BACKGROUND OF THE INVENTION

The present invention relates to a gasifier burner for a dry-feed pulverized coal gasification process.

The traditional way of utilizing coal is direct combustion, which is not only inefficient but also highly polluting, leading to increased emissions of sulfur dioxide, nitrogen oxides, and atmospheric mercury. In the past decade, the coal chemical industry has been influenced by environmental-protection factors and gradually developed in the direction of large-scale and greening. Coal gasification is an important way for clean utilization of coal, and the technology adapts to the requirements of sustainable economic development and has developed rapidly in recent years. Coal gasification technology is a technology that turns solid coal into gaseous hydrocarbons, CO, H₂ and other gases, with the aim of obtaining clean energy and chemical raw materials. The principle thereof is cause a chemical reaction between coal, coal coke, or petroleum coke and gasification agents (air, oxygen, water vapor, hydrogen, and the like) at a certain temperature and pressure, converting the organic matter in coal, coal coke or petroleum coke into coal gas. Entrained flow coal gasification processes can be further divided into coal-water slurry gasification and pulverized coal gasification. Compared with coal-water slurry gasification, pulverized coal gasification has the characteristics of high gasification efficiency, good performance indicators, wide application of coal types, and has relatively high techno-economic and environmental advantages.

In pulverized coal gasification processes, a pulverized coal burner is the core equipment of the gasifier, which is expensive and costs high in maintenance and replacement, having a large impact on the economy of gasifier operation. Since the burner is placed in the gasifier, the working environment is harsh, and the life thereof is relatively short in general. Therefore, the service life of pulverized coal burners has become the key to the long period operation of gasifiers. The part of a pulverized coal burner that is most prone to erosion is the fire-facing face of the burner, and the abrasion is mainly caused by the high temperature radiation or direct flame burning in the gasifier. Although extensive research has been conducted in the prior art on gasifier burners, there are still many problems remain to be solved.

In addition, food processing industry, paper industry and the downstream side of coal chemical industry produce a large amount of organic waste liquids, which may contain toxic and harmful substances such as benzene, phenol, phenanthrene, naphthalene, anthracene, quinone and the like, and may also contain organic substances such as carbohydrates, proteins, grease, lignin and the like. Organic waste liquid is prone to cause water eutrophication, which poses relatively large harm and requires complex process methods to handle, such as physical methods, extraction methods, adsorption methods, concentration methods, biodegradation methods and the like. The complexity in the composition of organic waste liquid is the key factor that makes it difficult to treat or degrade, and the increasingly demanding environmental-protection requirements urge chemical enterprises to invest a large amount of cost to deal with waste liquids produced in production.

Therefore, there is a need to develop a burner that can realize the functions of ignition start-up and of being thrown into waste liquids after the ignition start-up, while ensuring the cooling of the burner, increasing the service life thereof, shortening maintenance cycles, increasing production capacity, and reducing costs.

SUMMARY OF THE INVENTION

Aspects and advantages of the present invention will be set forth in part in the following characterizations, or may be apparent from the characterizations, or may be known by the practice of the invention.

The present invention provides a gasifier burner for a dry-feed pulverized coal gasification process, comprising: a first central pipe having a central axis; a first annular pipe concentrically surrounding the first central pipe, the first annular pipe comprising a plurality of first outlets at a head end of the gasifier burner; a second annular pipe concentrically surrounding the first annular pipe, the second annular pipe comprising a plurality of second outlets at a head end of the gasifier burner; and a third annular pipe concentrically surrounding the second annular pipe to form an outer wall of the gasifier burner, a head end of the first central pipe being fluidly connected to a head end of the third annular pipe by means of a connecting channel; characterized in that the first central pipe is for entry of cooling water and in that the third annular pipe is for leaving of the cooling water, so that cooling water flows along an inner side of a head end wall and an outer wall of the gasifier burner.

BRIEF DESCRIPTION OF DRAWINGS

A complete and realizable disclosure of the present invention for a person of ordinary skill in the art, including the best mode thereof, is set forth in the description with reference to the drawings, in which drawings:

FIG. 1 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to one embodiment;

FIG. 2 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to another embodiment;

FIG. 3 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to another embodiment; and

FIG. 4 shows an end view of a gasifier burner for a dry-feed pulverized coal gasification process according to another embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to embodiments of the present invention, one or more examples of which are shown in the drawings. Each example is provided by way of explaining the present invention rather than limiting the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope of the present invention. For example, features shown or described as part of one embodiment may be used in conjunction with another embodiment to produce yet another embodiment. Accordingly, the present invention is intended to cover such modifications and variations as are subsumed within the scope of the appended claims and equivalents thereof.

FIG. 1 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to one embodiment. This gasifier burner may be made of co-annular pipes comprising: a first central pipe 10 having a central axis; a first annular pipe 20 concentrically surrounding the first central pipe 10, the first annular pipe 20 comprising, at the head end of the gasifier burner, a plurality of (such as 8, 10, 12, 16) first outlets 25; a second annular pipe 30 concentrically surrounding the first annular pipe 20, the second annular pipe 30 comprising, at the head end of the gasifier burner, a plurality of (such as 8, 10, 12, 16) second outlets 35; and a third annular pipe 40 concentrically surrounding the second annular pipe 30 to form an outer wall of the gasifier burner. The head end of the first central pipe 10 may be fluidly connected to the head end of the third annular pipe 40 via a connecting channel 45.

The burner is used for supplying of the organic waste liquid to the dry-feed gasifier and to proceed in the dry-feed gasifier. For this purpose, the burner will supply the organic waste liquid, and oxygen streams, with a jacket cooling.

In one embodiment, the first central pipe 10 may be used for entry of cooling water 13 and the third annular pipe 40 may be used for leaving of cooling water 13, so that the cooling water 13 flows along an inner side of a head end wall and of an outer wall of the gasifier burner. In one embodiment, the first annular pipe 20 may be used for supplying fuel 23, the fuel 23 leaving through a plurality of first outlets 25, and the second annular pipe 30 may be used for supplying oxygen 33, the oxygen 33 leaving through a plurality of second outlets 35, causing the fuel 23 to be atomized. In one embodiment, the fuel 23may include organic waste liquid or diesel.

In one embodiment, a connecting channel 45 for returning of cooling water 13 may form a portion of the head end of the gasifier burner, such that the gasifier burner has a flat head end wall. The cooling water 13 may flow along the inner side of the head end wall of the gasifier burner.

In one embodiment, the head end of the first central pipe 10 may be indented relative to the head end of the third annular pipe 40, thereby forming a truncated conical portion between the head end of the first central pipe 10 and the head end of the third annular pipe 40. Cooling water 13 may flow along a side wall of the truncated conical portion to cool the truncated conical portion. The plurality of first outlets 25 and the plurality of second outlets 35 may be located on the side wall of the truncated conical portion. Preferably, co-annular nozzles may be perpendicular to the side wall of the truncated conical portion.

In one embodiment, each of the plurality of first outlets 25 may concentrically surround each of the plurality of second outlets 35, thereby forming a co-annular nozzle. The organic waste liquid/diesel will be atomized through the nozzles, and in the meantime, the oxygen 33 provided via the plurality of second outlets 35 may further assist to ensure the atomization performance.

The co-annular nozzles formed by said plurality of first outlets 25 and said plurality of second outlets 35 may be arranged symmetrically about said central axis to improve the uniformity of heating, as shown in FIG. 4. The focal point P of the co-annular nozzles is on the central axis. In one embodiment, the truncated conical portion has a side angle α in the range of 30 degrees to 120 degrees, preferably equal to 60 degrees.

The abovementioned co-annular nozzles can have the following features:
a. a liquid fuel velocity in the range of 5m/s to 20m/s;
b. an oxygen velocity in the range of 50m/s to 100m/s;
c. a droplet size generated from the atomization in the range of 0 to 500 μm, preferably in the
range of 0 to 250 μm;
d. a length to diameter ratio of the nozzle being ensured to be in the range of 3 to 20, preferably
in the range of 5 to 20.

FIG. 2 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to another embodiment. This gasifier burner is generally similar to the gasifier burner shown in FIG. 1, except that it incorporates a start-up burner function. In this embodiment, the gasifier burner may further comprise a second central pipe 50, the second central pipe 50 being concentrically surrounded by the first central pipe 10, the second central pipe 50 having a third outlet at the head end of the gasifier burner.

In one embodiment, the gasifier burner may further include a high-voltage (HV) igniter 60, the HV igniter being positioned in the second central pipe 50 at the third outlet. The high-voltage igniter 60 is aligned with the focal point P of the co-annular nozzles. Purging nitrogen (N₂) 53 may be supplied through the second central pipe 50 and leave from the third outlet.

During the start-up phase, the burner plays the role of a starter burner, with diesel fuel supplied via the first annular pipe 20 and oxygen supplied via the second annular pipe 30. The diesel/oxygen mixture will be ignited by the high-pressure igniter 60 at the focal point P. The flame will be stabilized in the truncated conical region and directed towards a reaction zone of the gasifier. Once the ignition of the burner is confirmed, the high-pressure igniter 60 will be turned off.

During normal operation, the diesel will be switched to the organic waste liquid and oxygen 33 will be supplied via the second annular pipe 30. A mixture of organic waste droplets and oxygen will be supplied to the reaction zone of the gasifier and participate in the gasification reaction.

The cooling water flowing along the inner side of the truncated conical portion of the burner and the flat head end wall will provide sufficient cooling to protect the nozzles and burner from overheating.

FIG. 3 shows a longitudinal cross-sectional view of a gasifier burner for a dry-feed pulverized coal gasification process according to another embodiment. The gasifier burner is generally similar to the gasifier burner shown in FIG. 2. This gasifier burner is not used for start-up and uses only organic waste liquids. In this embodiment, the gasifier burner can be modified to include an infrared thermography 70 positioned in the second central pipe 50 at the third outlet. The infrared thermography 70 is capable of detecting an overall temperature field in the reactor combustion zone, and is capable of determining a local temperature. Purging nitrogen 53 may be supplied through the second central pipe 50 and leave from the third outlet to protect the infrared thermography 70.

This written description uses examples to disclose the present invention including the best mode, and also enables any person skilled in the art to carry out the invention, including making and using any apparatus or system and performing any incorporated method. The scope of patentability of the present invention is limited by the claims and may include other examples that come to mind by those skilled in the art. These other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that are non-substantially different from the literal language of the claims.

Claims

A gasifier burner for a dry-feed pulverized coal gasification process, comprising:

a first central pipe having a central axis;

a first annular pipe concentrically surrounding the first central pipe, the first annular pipe comprising a plurality of first outlets at a head end of the gasifier burner;

a second annular pipe concentrically surrounding the first annular pipe, the second annular pipe comprising a plurality of second outlets at the head end of the gasifier burner; and

a third annular pipe concentrically surrounding the second annular pipe to form an outer wall of the gasifier burner, a head end of the first central pipe being fluidly connected to a head end of the third annular pipe by means of a connecting channel;

characterized in that the first central pipe is for entry of cooling water and in that the third annular pipe is for leaving of the cooling water, so that cooling water flows along an inner side of a head end wall and of the outer wall of the gasifier burner.
The gasifier burner according to claim 1, characterized in that the first annular pipe is for supplying fuel, the fuel leaving from the plurality of first outlets, and in that the second annular pipe is for supplying oxygen, the oxygen leaving from the plurality of second outlets, causing the fuel to be atomized.
The gasifier burner according to claim 2, characterized by

a. a velocity of fuel in a range of 5m/s to 20m/s;

b. a velocity of oxygen in a range of 50m/s to 100m/s;

c. a droplet size generated from atomization in a range of 0 to 500 μm.
The gasifier burner according to claim 3, characterized in that a droplet size generated from atomization is in a range of 0 to 250 μm.
The gasifier burner according to claim 1, characterized in that the fuel comprises organic waste liquid or diesel.
The gasifier burner according to claim 1, characterized in that the connecting channel forms a portion of a head end of the gasifier burner such that the gasifier burner has a flat head end wall.
The gasifier burner according to any one of claims 1 to 6, characterized in that a head end of the first central pipe is indented relative to a head end of the third annular pipe, thereby forming a truncated conical portion between the head end of the first central pipe and the head end of the third annular pipe, the plurality of first outlets and the plurality of second outlets being located on a side wall of the truncated conical portion, perpendicular to the side wall of the truncated conical portion.
The gasifier burner according to claim 7, characterized in that each of the plurality of first outlets concentrically surrounds each of the plurality of second outlets, thereby forming a co-annular nozzle.
The gasifier burner according to claim 8, characterized in that a length-to-diameter ratio of the co-annular nozzle is in a range of 3 to 20.
The gasifier burner according to claim 9, characterized in that a length-to-diameter ratio of the co-annular nozzle is in a range of 5 to 20.
The gasifier burner according to claim 8, characterized in that the co-annular nozzles formed by the plurality of first outlets and the plurality of second outlets are arranged symmetrically about the central axis.
The gasifier burner according to claim 7, characterized in that the truncated conical portion has a side angle in a range of 30 to 120 degrees.
The gasifier burner according to claim 12, characterized in that the truncated conical portion has a side angle equal to 60 degrees.
The gasifier burner according to claim 11, characterized by further comprising a second central pipe, the second central pipe being concentrically surrounded by the first central pipe, the second central pipe having a third outlet at a head end of the gasifier burner.
The gasifier burner according to claim 14, characterized by further comprising a high voltage sparker or an infrared thermography, the high voltage sparker or infrared thermography being positioned in the second central pipe at the third outlet.
The gasifier burner according to claim 15, characterized in that purging nitrogen is supplied through the second central pipe and leave from the third outlet.
A gasifier comprising the gasifier burner according to any one of claims 1 to 16.