A gasifier synthesis gas cooler

Abstract

The invention discloses a gasifier synthesis gas cooler, comprising a pressure shell unit and a tubular heating surface internal unit; the pressure shell unit comprises an upper head, a middle straight section cylinder and a lower cone section, a synthesis gas inlet is arranged on the upper head and a synthesis gas channel bottom cone extending into the middle straight section cylinder is arranged at the bottom of the upper head, the synthesis gas inlet is connected with the synthesis gas channel bottom cone to form a high-temperature synthesis gas channel; the tubular heating surface internal unit comprises a wall-wrapped membrane wall heating surface and a serpentine tube screen heating surface, the top of the wall-wrapped membrane wall in the wall-wrapped membrane wall heating surface is connected to the synthesis gas channel bottom cone through an expansion joint unit, an annular space is left between the wall-wrapped membrane wall and the side wall of the pressure shell unit, and multiple serpentine tube screen heating surfaces are arranged from top to bottom in the cylinder of the wall-wrapped membrane wall. The invention has a simple structure, is easy to manufacture, has a low cost and is easy to operate and maintain, and can be arranged in the radiation section of the gasifier or the rear end of the synthesis gas water bath process to further cool the synthesis gas.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat recovery of synthesis gas from a gasifier, and more particularly to a synthesis gas cooler for a gasifier. Background Art

[0002] The reaction temperature of modern coal chemical industry and (or oil) gasification process is about 1350℃~1600℃, and the gasification products are high-temperature and high-pressure synthesis gas and molten slag. The synthesis gas and molten slag at the outlet of the gasification chamber have a high temperature and contain a large amount of sensible heat. In order to improve the overall energy utilization rate, this part of the heat needs to be recovered. The use of waste heat boilers can recover 10%~13% of the calorific value of the coal entering the furnace. The saturated steam or superheated steam produced can be used in other processes in the chemical plant to improve the overall energy utilization efficiency; if used in IGCC power generation system, it can increase the power generation efficiency by 3%~5%.

[0003] There are two types of waste heat boilers for syngas in gasifiers: radiation boilers and convection boilers. At present, there are many semi-radiation and full-radiation boilers for recovering the heat of high-temperature syngas, but there are common problems of slagging and slag blockage on the heating surface. In addition, the radiation screen in the boiler chamber of the radiation waste heat boiler and the membrane wall of the furnace will produce a large expansion difference due to different heating or different material selection, making the radiation screen structure complex and unstable in operation, posing a safety hazard. In view of the many uncertainties of radiation waste boilers, gasifier convection waste boilers are particularly important as syngas cooling and heat recovery equipment.

[0004] The syngas cooler of Shell gasifier is one of the most commonly used convection waste boilers in gasifiers. Its structure is a combination of multiple sets of inner sleeve coils and cylindrical membrane walls. It is not only complex to manufacture and has a long cycle, but also has a high cost and is not easy to maintain in the later stage. In addition, many domestic universities and enterprises have also developed various convection waste boiler technologies, but they have never been able to overcome the problems of complex structure and manufacturing difficulties in design.

[0005] In view of the problems existing in the prior art, the present invention proposes a gasifier syngas cooler which can be installed in the radiation section of the gasifier or the rear end of the syngas water bath process to further cool the syngas, and is particularly suitable for sensible heat recovery projects of syngas from which the slag has been removed.

[0006] The present invention provides a gasifier syngas cooler, the gasifier syngas cooler comprising a pressure shell unit and a tubular heating surface internal unit;

[0007] The pressure housing unit comprises an upper end cap, a middle straight section cylinder and a lower cone section, wherein a synthesis gas inlet is arranged on the upper end cap and a synthesis gas channel bottom cone extending into the middle straight section cylinder is arranged at the bottom of the upper end cap, wherein the synthesis gas inlet is connected with the synthesis gas channel bottom cone to form a high-temperature synthesis gas channel;

[0008] The tubular heating surface internal unit comprises a wall-wrapped membrane wall heating surface and a serpentine tube panel heating surface, wherein the top of the wall-wrapped membrane wall in the wall-wrapped membrane wall heating surface is connected to the bottom cone of the synthesis gas channel through an expansion joint unit, an annular space is left between the wall-wrapped membrane wall and the side wall of the pressure shell unit, and multiple stages of serpentine tube panel heating surfaces are arranged from top to bottom in the cylinder of the wall-wrapped membrane wall;

[0009] Among them, the high-temperature synthesis gas is introduced into the high-temperature synthesis gas channel from the synthesis gas inlet of the gasifier synthesis gas cooler, and then enters the cylinder surrounded by the membrane wall in the tubular heating surface internal unit, flushes the serpentine tube screen heating surface, and exchanges heat with the water and / or steam in the membrane wall and the serpentine tube screen heating surface, and then is cooled and output.

[0010] According to an embodiment of the gasifier synthesis gas cooler of the present invention, the wall-wrapping membrane wall is supported on the inner wall of the middle straight section cylinder of the pressure shell unit through a first fixing unit, and the upper, middle and lower parts of the wall-wrapping membrane wall are respectively provided with guide units connected to the inner wall of the middle straight section cylinder of the pressure shell unit, and the lower part of the wall-wrapping membrane wall is suspended.

[0011] According to an embodiment of a gasifier synthesis gas cooler of the present invention, the wall-clad membrane wall superheater includes a wall-clad membrane wall, a first inlet and outlet header, a first inlet and outlet pipeline, an exhaust pipe and a first drain pipe, and both ends of the wall-clad membrane wall are respectively connected to the first inlet and outlet headers, and the first inlet and outlet headers are respectively connected to the external pipeline through the first inlet and outlet pipelines and exhaust and drain respectively through the exhaust pipe and the first drain pipe, wherein the first inlet and outlet headers, the first inlet and outlet pipelines, the exhaust pipe and the second drain pipe are all arranged in an annular space.

[0012] According to an embodiment of the gasifier synthesis gas cooler of the present invention, the serpentine tube panel heating surface is fixed in stages in the cylinder of the membrane wall by the second fixing unit, and the winding tubes of the serpentine tube panel in the serpentine tube panel heating surface are fixedly supported by the supporting unit, and each stage of the serpentine tube panel heating surface includes one or more serpentine tube panels and each serpentine tube panel is wound by one or more bare tubes.

[0013] According to an embodiment of the gasifier synthesis gas cooler of the present invention, the serpentine tube panel heating surface includes a multi-stage serpentine tube panel, a second inlet and outlet header, a second inlet and outlet pipe and a second drain pipe, and both ends of the serpentine tube panel are respectively connected to the second inlet and outlet header after passing through the membrane wall, and the second inlet and outlet header are respectively connected to the external pipe through the second inlet and outlet pipe and drained through the second drain pipe, wherein the second inlet and outlet header, the second inlet and outlet pipe and the second drain pipe are all arranged in an annular space.

[0014] According to an embodiment of the gasifier synthesis gas cooler of the present invention, a sealing box needs to be set at the position where the serpentine tube screen passes through the membrane wall; a plurality of soot blowing holes are opened on the membrane wall at intervals along the height direction and soot blowing units are arranged accordingly to correspond to each stage of the serpentine tube screen, and an inspection port is arranged on the opposite side of the soot blowing hole.

[0015] According to an embodiment of a gasifier syngas cooler of the present invention, the expansion joint unit includes a metal expansion joint, an upper sealing plate, a lower sealing plate and an inner insulation layer of the expansion joint, the upper sealing plate is connected to the bottom cone of the syngas channel and the lower sealing plate is connected to the membrane wall of the wall, and the inner insulation layer of the expansion joint is arranged on the inner surface of the metal expansion joint.

[0016] According to an embodiment of the gasifier syngas cooler of the present invention, a refractory insulation layer of a predetermined thickness is applied to the inner side of the high-temperature syngas channel, and an insulation layer is applied to the inner side of the middle straight section cylinder and the lower cone section of the pressure shell unit.

[0017] According to an embodiment of the gasifier synthesis gas cooler of the present invention, the cross section of the membrane wall is an equilateral or unequal polygon, and a plurality of individual hole units are provided on the pressure shell unit.

[0018] According to one embodiment of the gasifier syngas cooler of the present invention, the gasifier syngas cooler is arranged in the radiation section of the gasifier or the rear end of the syngas water bath process, wherein the water and / or steam in the wall membrane wall heating surface and the serpentine tube screen heating surface become saturated steam or superheated steam output after high-temperature heat exchange with the syngas.

[0019] Compared with the prior art, the novel gasifier syngas cooler of the present invention is in the form of a convection waste boiler and includes a pressure shell unit and a tubular heating surface internal unit, which uses water and / or steam as a coolant, and the water and / or steam exchange heat with the hot side syngas medium in the tube, and the produced saturated steam or superheated steam is sent to the steam network. The tubular heating surface internal unit in the present invention includes a wall membrane wall heating surface and a serpentine tube screen heating surface, which has a simple structure, is easy to manufacture, has a low cost, and is easy to operate and maintain. It can be installed in the radiation section of the gasifier or the rear end of the syngas water bath process to further cool the syngas, and is particularly suitable for sensible heat recovery projects of syngas from which the slag has been removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure shows an overall structural schematic diagram of a gasifier syngas cooler according to an exemplary embodiment of the present invention.

[0021] Figure 2 A schematic structural diagram of a pressure housing unit and a high-temperature syngas passage in a syngas cooler of a gasifier according to an exemplary embodiment of the present invention is shown.

[0022] Figure 3 A schematic structural diagram of a tubular heating surface internals unit in a gasifier syngas cooler according to an exemplary embodiment of the present invention is shown.

[0023] Figure 4 A simplified steam-water flow diagram of a gasifier syngas cooler according to an exemplary embodiment of the present invention is shown.

[0024] Description of reference numerals:

[0025] 100-pressure shell unit; 101-middle straight section cylinder; 102-lower cone section; 103-upper head; 104a, 104b, 104c-manhole units; 105a, 105b-syngas inlet; 106-insulation layer; 107-refractory insulation layer; 108-syngas channel bottom cone;

[0026] 200-tubular heating surface internal unit; 201-wall membrane wall; 202a, 202b-first inlet and outlet headers; 203a, 203b-first inlet and outlet pipelines; 204-exhaust pipe; 205-first drain pipe; 206-first fixed unit; 207a, 207b, 207c-guide unit; 208a, 208b-soot blowing holes and soot blowing units; 209-serpentine tube screen; 210a, 210b-second inlet and outlet headers; 211a, 211b-second inlet and outlet pipelines; 212-second drain pipe; 213-second fixed unit; 214-support unit;

[0027] 300- expansion joint unit; 301- metal expansion joint; 302a- upper sealing plate, 302b- lower sealing plate; 303- heat insulation layer inside the expansion joint;

[0028] 400-Annular space. DETAILED DESCRIPTION

[0029] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0030] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0031] Figure 1 The overall structural schematic diagram of a gasifier syngas cooler according to an exemplary embodiment of the present invention is shown. The gasifier syngas cooler of the present invention is in the form of a convection waste boiler, using water / steam as a coolant, and can produce saturated steam or superheated steam.

[0032] like Figure 1As shown, according to an exemplary embodiment of the present invention, the gasifier syngas cooler includes a pressure shell unit 100 and a tubular heating surface internals unit 200, wherein the tubular heating surface internals unit 200 is the main heat exchange heating unit of the cooler, and the pressure shell unit 100 is used to protect the tubular heating surface internals unit.

[0033] Figure 2 A schematic structural diagram of a pressure housing unit and a high-temperature syngas passage in a syngas cooler of a gasifier according to an exemplary embodiment of the present invention is shown.

[0034] like Figure 2 As shown, the pressure housing unit 100 includes an upper head 103, a middle straight section cylinder 101 and a lower cone section 102, and the upper head 103, the middle straight section cylinder 101 and the lower cone section 102 are connected from top to bottom to form the main body of the pressure housing unit 100. The upper head 103 is provided with syngas inlets 105a, 105b, and the syngas inlets can be provided at the top or the side of the upper head 103. The bottom of the upper head 103 is provided with a syngas channel bottom cone 108 extending into the middle straight section cylinder 101, and the syngas inlets 105a, 105b are connected with the syngas channel bottom cone 108 to form a high-temperature syngas channel, and the high-temperature syngas to be cooled enters the cold cooler through the syngas inlet and enters the subsequent cooling stage through the high-temperature syngas channel.

[0035] Preferably, a refractory insulation layer 107 of a predetermined thickness is applied to the inner side of the high-temperature synthesis gas channel to prevent overheating of the shell metal; an insulation layer 106 is applied to the inner side of the middle straight section cylinder 101 and the lower cone section 102 of the pressure shell unit 100 to ensure that the shell metal wall temperature is within the design allowable range; and a plurality of individual manhole units 104a, 104b, 104c are also provided on the pressure shell unit 100 for easy maintenance.

[0036] Figure 3 A schematic structural diagram of a tubular heating surface internals unit in a gasifier syngas cooler according to an exemplary embodiment of the present invention is shown.

[0037] like Figure 3 As shown, the tubular heating surface internal component unit 200 includes a wall membrane wall heating surface and a serpentine tube panel heating surface. Among them, the top of the wall membrane wall 201 in the wall membrane wall heating surface is connected to the bottom cone 108 of the synthesis gas channel through the expansion joint unit 300, an annular space 400 is left between the wall membrane wall 201 and the side wall of the pressure shell unit 100, and multiple stages of serpentine tube panel heating surfaces are arranged from top to bottom in the cylinder of the wall membrane wall 201, such as superheaters, evaporators, preheaters, etc.

[0038] Preferably, the cross section of the membrane wall 201 is an equilateral or unequal polygon and forms a space for accommodating the serpentine tube panel in the serpentine tube panel heating surface.

[0039] According to the present invention, the membrane wall 201 is supported on the inner wall of the middle straight section cylinder 101 of the pressure housing unit 100 through the first fixing unit 206, and the upper, middle and lower parts of the membrane wall 201 are respectively provided with a plurality of guide units 207a, 207b and 207c connected to the inner wall of the middle straight section cylinder 101 of the pressure housing unit 100, and the lower part of the membrane wall 201 is suspended. The guide unit can prevent the cylinder from shaking, the heating surface of the membrane wall is fixed in the pressure housing unit 100 as a whole, and the serpentine tube panel is fixed on the inner side of the membrane wall 201.

[0040] Specifically, the heating surface of the membrane wall includes a membrane wall 201, a first inlet and outlet manifold 202a, 202b, a first inlet and outlet pipe 203a, 203b, an exhaust pipe 204 and a first drain pipe 205. The two ends of the membrane wall 201 are respectively connected to the first inlet and outlet manifold 202a, 202b. The first inlet and outlet manifold 202a, 202b are respectively connected to the external pipe through the first inlet and outlet pipe 203a, 203b and exhaust and drain are respectively performed through the exhaust pipe 204 and the first drain pipe 205.

[0041] The first inlet and outlet headers 202a, 202b, the first inlet and outlet pipes 203a, 203b, the exhaust pipe 204 and the second drain pipe 205 are all arranged in the annular space 400. Preferably, the first inlet headers of the first inlet and outlet headers 202a, 202b are arranged at the upper part and the first outlet headers are arranged at the lower part, the exhaust pipe 204 is connected to the first inlet header of the first inlet and outlet headers, and the first drain pipe 205 is connected to the first outlet header of the first inlet and outlet headers, but the present invention is not limited thereto.

[0042] According to the present invention, the serpentine tube panel heating surface is fixed in stages in the cylinder of the membrane wall 201 through the second fixing unit 213, and the winding space of the serpentine tube panel 209 in the serpentine tube panel heating surface is fixedly supported by the supporting unit 214. Each stage of the serpentine tube panel heating surface includes one or more serpentine tube panels (such as 15 to 20 panels), and each serpentine tube panel is wound by one or more light tubes.

[0043] Preferably, the serpentine tube panel heating surface includes a multi-stage serpentine tube panel 209, a second inlet and outlet header 210a, 210b, a second inlet and outlet pipe 211a, 211b and a second drain pipe 212. Both ends of the serpentine tube panel 209 are connected to the second inlet and outlet headers 210a, 210b respectively after passing through the membrane wall 201. The second inlet and outlet headers 210a, 210b are connected to the external pipes through the second inlet and outlet pipes 211a, 211b respectively and drain 212 through the second drain pipe.

[0044] The second inlet and outlet headers 210a, 210b, the second inlet and outlet pipes 211a, 211b and the second drain pipe 212 are all arranged in the annular space. Preferably, the second inlet header of the second inlet and outlet headers is arranged at the upper part and the second outlet header is arranged at the lower part, and the second drain pipe 212 is connected to the second outlet header of the second inlet and outlet headers, but the present invention is not limited thereto.

[0045] A sealing box needs to be provided at the position where the serpentine tube panel 209 passes through the membrane wall 201 to ensure the sealing. In addition, in order to prevent the serpentine tube panel from breaking, a number of soot blowing holes and soot blowing units 208a, 208b are provided at intervals along the height direction on the membrane wall 201 to correspond to each stage of the serpentine tube panel and to perform soot blowing treatment on it. An inspection port is arranged on the opposite side of the soot blowing hole to facilitate the installation of the soot blower and the inspection of the serpentine tube panel 209.

[0046] Thus, the high-temperature synthesis gas is introduced into the high-temperature synthesis gas channel from the synthesis gas inlet of the gasifier synthesis gas cooler, and then enters the cylinder surrounded by the membrane wall in the tubular heating surface internal unit, flushes the serpentine tube panel heating surface, and exchanges heat with the water and / or steam in the membrane wall and the serpentine tube panel heating surface, and then is cooled and output; the water and / or steam in the membrane wall heating surface and the serpentine tube panel heating surface become saturated steam or superheated steam after high-temperature heat exchange with the synthesis gas, and is output to the steam pipeline network.

[0047] The expansion joint unit 400 of the present invention includes a metal expansion joint 301, an upper sealing plate 302a, a lower sealing plate 302b and an inner insulation layer 303 of the expansion joint. The upper sealing plate 302a is connected to the bottom cone 108 of the synthesis gas channel and the lower sealing plate 302b is connected to the membrane wall 201 of the wall, thereby allowing high-temperature synthesis gas to be smoothly introduced into the tubular heating surface internal unit 200 for cooling; the inner insulation layer 303 of the expansion joint is arranged on the inner side of the metal expansion joint (for example, it can be directly arranged on the inner surface or arranged at a distance from the inner surface) to isolate the metal expansion joint 301 from the high-temperature synthesis gas.

[0048] In summary, the gasifier synthesis gas cooler of the present invention has a simple structure, is easy to manufacture, has a low cost and is easy to operate and maintain, wherein the tubular heating surface internal unit support method is simple and reliable; the upper head in the pressure shell unit is used as a synthesis gas inlet channel to connect with the outside world, has a simple structure, a short process flow and a small pressure loss; the steam / water side process parameter adjustment margin is large, and saturated steam or superheated steam can be produced arbitrarily; the annular space also serves as a maintenance channel, which is convenient for maintenance work.

[0049] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A gasifier syngas cooler, characterized in that: The gasifier syngas cooler comprises a pressure shell unit and a tubular heating surface internals unit; The pressure housing unit comprises an upper end cap, a middle straight section cylinder and a lower cone section, wherein a synthesis gas inlet is arranged on the upper end cap and a synthesis gas channel bottom cone extending into the middle straight section cylinder is arranged at the bottom of the upper end cap, wherein the synthesis gas inlet is connected with the synthesis gas channel bottom cone to form a high-temperature synthesis gas channel; The tubular heating surface internal unit comprises a wall-wrapped membrane wall heating surface and a serpentine tube panel heating surface, wherein the top of the wall-wrapped membrane wall in the wall-wrapped membrane wall heating surface is connected to the bottom cone of the synthesis gas channel through an expansion joint unit, an annular space is left between the wall-wrapped membrane wall and the side wall of the pressure shell unit, and multiple stages of serpentine tube panel heating surfaces are arranged from top to bottom in the cylinder of the wall-wrapped membrane wall; The high-temperature synthesis gas is introduced into the high-temperature synthesis gas channel from the synthesis gas inlet of the synthesis gas cooler of the gasifier, and then enters the cylinder surrounded by the membrane wall in the tubular heating surface internal unit, flushes the serpentine tube panel heating surface, exchanges heat with water and / or steam in the membrane wall and the serpentine tube panel heating surface, and then is cooled and output; The wall-wrapped membrane wall heating surface comprises a wall-wrapped membrane wall, a first inlet and outlet header, a first inlet and outlet pipeline, an exhaust pipe and a first drain pipe, both ends of the wall-wrapped membrane wall are respectively connected to the first inlet and outlet header, the first inlet and outlet header are respectively connected to the external pipeline through the first inlet and outlet pipeline, and exhaust and drain are respectively performed through the exhaust pipe and the first drain pipe, wherein the first inlet and outlet header, the first inlet and outlet pipeline, the exhaust pipe and the second drain pipe are all arranged in an annular space; The serpentine tube panel heating surface includes a multi-stage serpentine tube panel, a second inlet and outlet header, a second inlet and outlet pipe and a second drain pipe. Both ends of the serpentine tube panel are respectively connected to the second inlet and outlet header after passing through the membrane wall. The second inlet and outlet header is respectively connected to the external pipe through the second inlet and outlet pipe and drains water through the second drain pipe, wherein the second inlet and outlet header, the second inlet and outlet pipe and the second drain pipe are all arranged in the annular space.

2. The gasifier syngas cooler according to claim 1, characterized in that: The wall-wrapping membrane wall is supported on the inner wall of the middle straight cylinder section of the pressure shell unit through a first fixing unit, and guide units connected to the inner wall of the middle straight cylinder section of the pressure shell unit are respectively arranged at the upper, middle and lower parts of the wall-wrapping membrane wall, and the lower part of the wall-wrapping membrane wall is suspended.

3. The gasifier syngas cooler according to claim 1, characterized in that: The serpentine tube panel heating surface is fixed in stages in the cylinder of the membrane wall by the second fixing unit, and the winding tubes of the serpentine tube panel in the serpentine tube panel heating surface are fixedly supported by the supporting unit. Each stage of the serpentine tube panel heating surface includes one or more serpentine tube panels and each serpentine tube panel is wound by one or more light tubes.

4. The gasifier syngas cooler according to claim 1, characterized in that: A sealing box needs to be set at the position where the serpentine tube screen passes through the membrane wall; a plurality of soot blowing holes are arranged at intervals along the height direction on the membrane wall and soot blowing units are arranged accordingly to correspond to each level of the serpentine tube screen, and an inspection port is arranged on the opposite side of the soot blowing hole.

5. The gasifier syngas cooler according to claim 1, characterized in that: The expansion joint unit includes a metal expansion joint, an upper sealing plate, a lower sealing plate and an inner insulation layer of the expansion joint, wherein the upper sealing plate is connected to the bottom cone of the synthesis gas channel and the lower sealing plate is connected to the membrane wall of the wall, and the inner insulation layer of the expansion joint is arranged on the inner side of the metal expansion joint.

6. The gasifier syngas cooler according to claim 1, characterized in that: The inner side of the high-temperature synthesis gas channel is coated with a refractory heat-insulating layer of a predetermined thickness, and the inner sides of the middle straight section cylinder and the lower cone section of the pressure shell unit are coated with a heat-insulating layer.

7. The gasifier syngas cooler according to claim 1, characterized in that: The cross section of the membrane-cladding wall is an equilateral or unequal polygon, and a plurality of individual hole units are arranged on the pressure housing unit.

8. The gasifier syngas cooler according to claim 1, characterized in that: The gasifier syngas cooler is arranged in the radiation section of the gasifier or the rear end of the syngas water bath process, wherein the water and / or steam in the wall membrane wall heating surface and the serpentine tube panel heating surface become saturated steam or superheated steam output after high-temperature heat exchange with the syngas.

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