Title of Invention

SYNTHESIS GAS HEAT EXCHANGER APPARATUS

Abstract The present invention relates to a synthesis-gas heat-exchanger apparatus comprising a synthesis-gas radiation cooler, a crude-gas/pure-gas heat exchanger, a crude-gas/inert-gas heat exchanger and at least one dust separator characterized in that at least one crude-gas/pure-gas heat exchanger with upper connecting lines and transition pieces is arranged at right-angles or with an inclination after the synthesis-gas radiation cooler on one side, and at least one crude-gas/inert-gas heat exchanger with upper connecting lines and transition pieces is arranged at right-angles or with an inclination on the other side, the crude-gas/pure-gas heat exchanger and the crude-gas/inert-gas heat exchanger are equipped with a soot blower system, and the lower connecting lines are provided with a crude-gas mass-flow regulator and are connected to a separator.
Full Text

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The present invention pertains to a synthesis gas heat exchanger unit with one synthesis gas radiant cooler, two synthesis gas convection coolers, one crude gas-clean gas heat exchanger, one crude gas-inert gas heat exchanger, and at least one separator or without a synthesis gas radiant cooler.
Heat exchanger units in which the synthesis gas radiant cooler is installed vertically and the synthesis gas convection cooler, the crude gas-clean gas heat exchanger as well as the crude gas-nitrogen heat exchanger are installed horizontally have been known.
Even though this arrangement offers the advantage of a small overall height of the equipment installed, it entails the decisive drawback that there is a risk of encrustation and clogging of the horizontal heat exchanger tubes and of the connection lines by the flue dust and slag particles carried by the synthesis gas.
Residual dust remains as a dust deposit in the heat exchanger tubes after the unit has been switched off, because there is no self-cleaning due to the force of gravity of the horizontal tubes. If moisture enters the system during the stopping and/or during the heat-up/start-up period, the residual dust may solidify and bake on the heat exchanger tubes. This is the source of complete clogging of the tubes during the subsequent operation. The units with clogged tubes are no longer able to function, and the consequence of this is the shutdown of the entire unit, loss of production, and later expensive cleaning of the heat exchanger tubes and of the connection lines.
The object of the present invention is therefore to provide a synthesis gas heat exchanger unit, whose self-cleaning from residual particles, dust deposits and other solid particles is

improved during the hot operation, during the start-up phase and during shutdown, in which the mass flows in the individual heat exchanger flues are controlled and in which interruptions of operation and increased maintenance costs are avoided.
This object is accomplished corresponding to the features of the two principal claims; the subclaims describe an advantageous embodiment of the present invention.
According to the present invention, the system for cooling and cleaning the synthesis gas, i.e., heat exchange of crude gas with high/medium-pressure water/clean gas or nitrogen has the following functional details:
1) Vertical or sloped arrangement of the equipment for cleaning by the force of gravity,
2) possibility of soot blow-off to eliminate residual dusts after the switching off of the unit as well as supporting cleaning of the heat exchanger tubes and connection pipelines during the operation,
3) possibility of adjustment (possibility of control) of the mass flows of the individual heat exchanger lines in the upper feed lines and/or in the connection pipelines to the dust separator,
4) heating (e.g., electric) for start-up processes, preferably at the crude gas heat exchangers and at the lower connection lines,
5) compensation of the thermal expansion by elastic suspension of the synthesis gas convection coolers and of the crude gas/gas heat exchangers, and installation of compensators in the connection pipelines, and
6) accessibility of the inlets and outlets of synthesis gas convection coolers, crude gas-clean gas heat exchangers, and

crude gas-nitrogen heat exchangers through handholes and
manholes.
According to the present invention, the vertical or sloped arrangement of the heat exchangers reliably prevents the development of clogging due to dust in the unit consisting of the following equipment connected to one another vertically or slopingly even during the operation: Synthesis gas radiant cooler, synthesis gas convection cooler, crude gas-clean gas heat exchanger, crude gas-nitrogen heat exchanger, separator with mass flow controllers, soot blowers as well as special support.
Due to the vertical or greatly sloped arrangement of the heat exchangers, the force of gravity of the dust particles causes during the operation and after the switching off of the heat exchanger unit that no residual dust can solidify and bake on in the heat exchanger tubes.
Furthermore, the soot blower systems provided can be activated during the operation and after the switching off of the unit and they can supportingly blow the heat exchanger tubes dust-free, so that a premature clogging can be avoided during the operation, on the one hand, and residual deposits can be reliably avoided, on the other hand.
The function and the task of the synthesis gas heat exchanger unit is to cool a synthesis gas, which is generated, e.g., during the gasification of coal, from a combustion temperature of about 1,850°C to 1,400°C to room temperature in order to feed the gas to a downstream cold gas cleaning unit. After this cleaning, the synthesis gas or crude gas has become a so-called "clean gas," which is sent through the crude gas-clean gas heat exchanger for preheating for further use and is then sent to a gas turbine or other users.

If the "hot gas cleaner" currently being developed is to be used, the "cooling path" of the gas is shortened depending on the
needs, and the main stream or also the partial stream is sent into
\ the hot gas cleaner.
During the cooling of the synthesis gas in the synthesis gas heat exchanger unit, the sensible heat of the synthesis gas is used to generate steam and to preheat the clean gas and of nitrogen or inert gases.
The object of the optimization of the unit is to set the inlet and outlet temperatures of the individual equipment. This determines the corresponding geometries of the equipment, and the optimization is to be performed based on such factors as the equipment costs, the efficiency, the quality of function, etc.
When following the path of the gas, it is seen that the synthesis gas flows through the synthesis gas radiant cooler at a relatively low velocity in the direction of the falling slag. The circulating flow in the boiler tubes is directed opposite the gas flow. At the end of the synthesis gas radiant cooler, the synthesis gas leaves the synthesis gas radiant cooler via, e.g., two gas outlet lines offset by 180° and flows into a vertically or slopingly arranged synthesis gas convection cooler with its straight heat exchanger tubes. The synthesis gas flows through these tubes, which are cooled with water in counterflow from the outside. The synthesis gas convection cooler is joined by the gas/gas heat exchangers, likewise arranged vertically or slopingly (crude gas-clean gas heat exchanger/crude gas-inert gas heat exchanger). These heat exchangers likewise comprise straight tubes, which are operated in counterflow, parallel flow or cross-flow.
A further cooling of the synthesis gas takes place here, on

the one hand, and the cleaned synthesis gas and an inert gas, e.g. nitrogen, which is supplied by an air separation installation, are preheated, on the other hand. The clean gas and the nitrogen are sent to the combustion chamber of a gas turbine, where the clean gas is burned.
The nitrogen reduces the combustion temperature, which prevents (reduces) the formation of nitrogen oxides, and it also increases the volume flow of the gas that is sent to the turbine blades.
The two flues of the synthesis gas convection coolers and of the crude gas/clean gas and crude gas/inert gas heat exchangers with their connection lines are designed as heat exchangers of completely identical shape and are arranged identically; nevertheless, there is a risk of nonuniform mass flow distribution of the synthesis gas in the two flues. If this imbalance of the mass flows is not corrected at the beginning, this imbalance will increase during the running operation. This may lead to the system becoming unable to function and thus to the switching off of the unit.
This imbalance is prevented by controlling the mass flow in every individual flue either before the synthesis gas convection cooler or after the crude gas/gas heat exchangers in the connection lines leading to the dust separator. It is ensured as a result that all synthesis gas lines will carry the same mass flow of synthesis gas, which leads to a controlled ability of the system to function.
Another measure to avoid cloggings due to dust is to provide the crude gas-clean gas/crude gas-nitrogen (inert gas) heat exchangers and the lower connection lines with heating in order to prevent preheating and/or start-up from occurring at temperatures

below the dew point. The heating may be electric; it is activated during the start-up operation and is switched off during stable operation.
The system according to the present invention is a hot-running system undergoing radial and longitudinal expansions, which must be taken into account at the time of installation. The longitudinal elongations are, of course, most relevant.
The support system has its upper fixed point at the synthesis gas radiant cooler and has elastic supports at the synthesis gas convection coolers and the crude gas-clean and crude gas-inert gas heat exchangers, as well as fixed supports or elastic supports at the separator. If necessary, compensators are to be provided at the lower connection lines in order to reduce stresses in the system.
The heat exchanger synthesis gas unit (sic - synthesis gas heat exchanger unit - Tr.Ed.) according to the present invention is used, e.g., in a coal-fired power plant with upstream coal gasification plant after the reactor.
Accordingly the present invention provides a synthesis-gas heat-exchanger apparatus comprising a synthesis-gas radiation cooler, a crude-gas or pure-gas heat exchanger, a crude-gas or inert-gas heat exchanger and at least one dust separator characterized in that at least one crude-gas or pure-gas heat exchanger with upper connecting lines and transition pieces is arranged at right-angles or with an inclination after the synthesis-gas

radiation cooler on one side, and at least one crude-gas or inert-gas heat exchanger with upper connecting lines and transition pieces is arranged at right-angles or with an inclination on the other side, the crude-gas or pure-gas heat exchanger and the crude-gas or inert-gas heat exchanger are equipped with a soot blower system, and the lower connecting lines are provided with a crude-gas mass-flow regulator and are connected to a separator.
The present invention will be explained in great detail with reference to the accompanying drawings, in which;
Figure 1 shows a front view of the synthesis gas heat exchanger unit,
Figure 2 shows top view of the synthesis gas heat exchanger unit with a separator,
Figure 3 shows a top view of the synthesis gas heat exchanger unit with two separators,
Figure 4 shows a top view of the synthesis gas heat exchanger unit with individual branches and two separators,
Figure 5 shows a front view of the synthesis gas heat exchanger

siopingiy arrangea neat exchangers, and Figure 6 shows a front view of the synthesis gas heat exchanger unit with gas/gas heat exchangers.
Figure 1 shows a front view of the heat exchanger unit with the synthesis gas radiant coolers (1) mounted on fixed points (17), from which two upper connection lines (2) lead to the synthesis gas convection coolers (23) via branch pieces (3) and the control fittings (30). Both synthesis gas convection cooler lines are designed as double-flue lines (23.1, 2 3.2) and are elastically supported (12) via claws (10). The synthesis gas convection coolers (23) have straight fire tubes (27), the heat exchange taking place by cooling water flowing in counterflow, which is fed to the synthesis gas convection cooler (23) via the pipe branches (24) and is drawn off via the pipe branches (25).
A soot blower system (13) is associated with each flue (23.1, 23.2). Soot blowers (31) are also arranged in the connection lines (2). Furthermore, handholes/manholes (18) are present at the synthesis gas inlets and outlets of the synthesis gas convection coolers (23).
The synthesis gas, cooled from about 900°C-600°C to about 600°C-300"C, enters the crude gas/clean gas heat exchangers (4.1, 4.2), on the one side, while the synthesis gas is admitted to the crude gas-nitrogen (inert gas) heat exchangers (5.1, 5.2), on the other side.
The above-mentioned heat exchangers (4, 5) are supported elastically via claws (10). They have straight fire tubes (28), the heat exchange taking place via clean gas or inert gas (nitrogen) with the corresponding inlet and outlet pipe branches (clean gas 15.1, 15.2/nitrogen 16.1, 16.2).
One or more soot blower systems (13) are associated with each

flue (4.1, 4.2; 5.1, 5.2). Furthermore, handholes/manholes (18) are present in the synthesis gas inlets and outlets of the crude gas/clean gas (4) and crude gas-nitrogen heat exchangers (5), and a heater (9) is likewise provided for the heat exchangers (23) and (4, 5).
The synthesis gas cooled to about 250°C-180°C in the heat exchangers (4, 5) leaves same via lower connection lines (6) and enters the central separator (11), which is mounted elastically (12) on claws (20) or is designed as a fixed point (17).
One control fitting (29) and/or one crude gas mass flow controller (7) is installed in the connection lines (6). Pressurized water connections (8), a heater (9) and compensators (19), as well as the soot blower system (31) are additionally provided.
A slag breaker (14), into which the slag components separated from the crude or synthesis gas enter, is arranged under the synthesis gas cooler (1).
Figure 2 shows a top view of the heat exchanger unit with a synthesis gas radiant cooler (1) and a central dust separator (1). The uncleaned crude gas enters both the crude gas/clean gas heat exchanger (4) and the crude gas/nitrogen heat exchanger (5) via the upper connection lines (2) with adjoining branch pieces (3), control fittings (30) and soot blowers (13, 31) over the synthesis gas convection coolers (23.1, 23.2), and the uniform distribution of the crude gas is controlled via mass flow controllers (7) and control fittings (30) arranged in the lower connection lines (6) and/or via the upper control fitting (30).
Figure 3 shows a top view of the heat exchanger unit with a synthesis gas radiant cooler (1) and two decentralized dust separators (11.1) and (11.2). The uncleaned crude gas likewise

enters the downstream crude gas/clean gas heat exchangers (4) as well as the crude gas/nitrogen heat exchangers (5) via the upper connection lines (2) with adjoining branch pieces (3), control fittings (29) and soot blowers (13, 31) over the synthesis gas convection coolers, and uniform distribution of the crude gas is controlled via mass flow controllers (7) and control fittings (29) arranged in the lower connection lines (6).
Figure 4 shows a top view of the heat exchanger unit with a synthesis gas radiant cooler (1) and two decentralized dust separators (11.1) and (11.2).
Four connection lines (2) are branched off from the synthesis gas radiant cooler (1); they send the crude gas via control fittings (30) and soot blowers (13, 31) and over the synthesis gas convection coolers (23.1, 23.2) into the downstream crude gas-clean gas heat exchangers (4) as well as into the crude gas-nitrogen heat exchangers (5), and uniform distribution of the crude gas is ensured by mass flow controllers (7) and control fittings (29) arranged in the lower connection lines (6).
Pipe branches (15) for the clean gas inlet and outlet and pipe branches (16) for the nitrogen inlet and outlet are provided for cooling the crude gas to the necessary temperatures.
The lower connection lines (6) are equipped with mass flow controllers (7), pressurized water connections (8), soot blowers (31), as well as a heater (9). The support on the fixed points (17) is ensured as was described above.
Figure 5 shows a front view of the heat exchanger unit described before under Figure 1, but with slopingly arranged synthesis gas convection coolers (23) and slopingly arranged clean gas and nitrogen heat exchangers (4, 5), which are connected to one another by middle, curved connection lines (22) with devices for

introducing soot blower lances. All heat exchangers are provided at the inlet with a soot blower system (13). Mass flow controllers (7) and control fittings (29) as well as soot blowers (31) are likewise provided in the lower connection lines (6) leading to the central dust separator (11) .
The slopingly arranged synthesis gas convection coolers (23) and the clean gas and nitrogen heat exchangers (4, 5) are mounted on fixed points (17) via slide bearings (21) and via elastic supports (12) , respectively. The central dust separator (11) is mounted, as was described above, via claws (2 0) and elastically (12) or via fixed supports (17).
Figure 6 shows a modified arrangement of Figure l. The use of the synthesis gas convection coolers was abandoned here, because the outlet temperature from the synthesis gas radiant cooler (gas quencher) is so low that the synthesis gas convection coolers are not needed.
All other elements, such as the soot blowers (13, 31), the crude gas mass flow controller (7), the control fitting (29), the heater (9), the elastic support (12), the compensators (19), etc., which are described in Figure 1, are used here.
List of Reference Numbers
1 Synthesis gas radiant cooler
2 Transition line/upper connection line
3 Branch piece
4 Crude gas/clean gas heat exchanger
4 .1 Right-hand flue
4.2 Left-hand flue
5 Crude gas/inert gas heat exchanger

5.1 Right-hand flue
5.2 Left-hand flue

6 Lower connection line
7 Crude gas mass flow controller
8 Pressurized water connection
9 Heater

10 Claws
11 Central separator

11.1 Independent separator after 4
11.2 Independent separator after 5

12 Elastic support
13 Soot blower system
14 Slag breaker
15 Clean gas inlet and outlet
16 Inert gas inlet and outlet
17 Fixed point
18 Handhole/manhole
19 Compensator
20 Claws
21 Slide bearing
22 Middle connection line
23 Synthesis gas convection cooler

23.1 Right-hand flue
23.2 Left-hand flue

24 Cooling water inlet
25 Cooling water outlet

27 Fire tube
28 Fire tube
29 Control fitting
30 Control fitting
31 6aot blovicv


WE CLAIM:
1. A synthesis-gas heat-exchanger apparatus comprising a synthesis-gas radiation cooler (1), a crude-gas or pure-gas heat exchanger (4), a crude-gas or inert-gas heat exchanger (5) and at least one dust separator (11) characterized in that at least one crude-gas or pure-gas heat exchanger (4) with upper connecting lines (2) and transition pieces (3) is arranged at right-angles or with an inclination after the synthesis-gas radiation cooler (1) on one side, and at least one crude-gas or inert-gas heat exchanger (5) with upper connecting lines (2) and transition pieces (3) is arranged at right-angles or with an inclination on the other side, the crude-gas or pure-gas heat exchanger (4) and the crude-gas or inert-gas heat exchanger (5) are equipped with a soot blower system (13), and the lower connecting lines (6) are provided with a crude-gas mass-flow regulator (7) and are connected to a separator (11).
2. The synthesis-gas heat-exchanger apparatus according to claim 1, wherein at least one synthesis-gas convection cooler (23) in each case is arranged before the crude-gas or pure-gas heat exchanger (4) and before the crude-gas or inert-gas heat exchanger (5).
3. The device according to claim 1, wherein soot blowers (31) are arranged in the upper connecting lines (2) and in the lower connecting lines (6).
4. The device according to claim 2, wherein the synthesis-gas convection coolers (23) are single-duct or multi-duct.

5. The device according to claim 1, wherein the crude-gas or pure-gas exchanger (4) and the crude-gas or inert-gas exchanger (5) are single-duct or multi-duct.
6. The device according to claim 1, wherein the crude-gas or pure-gas exchanger (4) is connected to a single dust separator (11.1) and the crude-gas or inert-gas exchanger (5) is connected to a single dust separator (11.2) and the lower connecting lines (6) are provided with a crude-gas mass flow regulator (7).
7. The device according to claims 1 and 2 wherein the synthesis-gas convection cooler (23), the crude-gas or pure-gas exchanger (4), the crude-gas or inert-gas exchanger (5) and the lower connecting lines (6) are equipped with an electric heating means (9).
8. The device according to claim 1, wherein compensators (19) are provided at the inlet into the lower connecting lines (6).
9. The device according to claim 1, wherein pressurized-water connections (8) are arranged in the lower connecting lines (6) above the crude-gas mass-flow regulators (7).
10. The device according to claims 1 and 2, wherein the synthesis-gas radiation cooler (1) is displaced via a fixed-point support (17), the synthesis-gas convection cooler (23), the crude-gas or pure-gas exchanger (4) and the craide-gas or inert-gas exchanger (5) via claws (10) on elastic supports (12).

11. The device according to claim 1, wherein the central dust separator (11) and the individual dust separators (11.1, 11.2) are displaced via claws (20) on elastic supports or via fixed-point supports (17).
12. The device according to claim 1, wherein a regulating fitting (30) is provided in the upper connecting line (2).
13. The device according to claim 1, wherein the lower connecting
line (6) has a pressurised-water connecting (8).
14. A synthesis-gas heat-exchanger apparatus substantially as
herein above described with reference to the accompanying drawings.


Documents:

2684-mas-97 abstract-duplicate.pdf

2684-mas-97 abstract.pdf

2684-mas-97 assignment.pdf

2684-mas-97 claims-duplicate.pdf

2684-mas-97 claims.pdf

2684-mas-97 correspondence-others.pdf

2684-mas-97 correspondence-po.pdf

2684-mas-97 description (complete)-duplicate.pdf

2684-mas-97 description (complete).pdf

2684-mas-97 drawings-duplicate.pdf

2684-mas-97 drawings.pdf

2684-mas-97 form-10.pdf

2684-mas-97 form-19.pdf

2684-mas-97 form-2.pdf

2684-mas-97 form-26.pdf

2684-mas-97 form-4.pdf

2684-mas-97 form-6.pdf

2684-mas-97 others.pdf

2684-mas-97 petition.pdf


Patent Number 196415
Indian Patent Application Number 2684/MAS/1997
PG Journal Number 30/2009
Publication Date 24-Jul-2009
Grant Date 20-Dec-2005
Date of Filing 24-Nov-1997
Name of Patentee M/S. METALLGESELLSCHAFT AG
Applicant Address D-60325 FRANK FURT AM MAIN
Inventors:
# Inventor's Name Inventor's Address
1 DIPL.-ING. WOLFGANG DEEKE HAYDNSTRABE 152, D-40822 METTMANN
2 DIPL., ING. WOLFRAM GRUHLKE ROSENSTRABE 44, 47918 TOENIS-VORST(D)
3 DR. ING. JURGEN HEERING RHEINDAMM 13, 40668 MEERBUSCH (D)
4 DIPL.-ING. KLAUS KOHNEN LUXEMBURGER ALLEE 49, 45481 MUTHEIM(D)
PCT International Classification Number F28G13/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 196 49 532.6 1996-11-29 Germany