JP2002286379A - Steam and hot water generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of the whole of an exhaust heat boiler device and simplify the whole of the device, in a heat cycle power generating device using small capacity gas turbine device and the exhaust heat boiler device. SOLUTION: A plurality of heat transfer pipes form spiral structures having the identical pitch and different diameters. The heat transfer pipes are aligned in a multiple concentric state and contained between the outer and inner drums of an annular cylindrical exhaust drum erected in a vertical direction.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust heat boiler and a hot water generator of a heat cycle power generator using a gas turbine and an exhaust heat boiler. 2. Description of the Related Art As a heat cycle power generation device using a gas turbine device and a waste heat boiler device, a conventional combined cycle device or chain cycle device has been used as a large / medium capacity machine of several thousand to several hundred thousand kW. Has been used. FIG. 2 shows a typical example of a waste heat boiler device constituting such a power generation device. A is an economizer heat transfer tube, B is a steam drum, C is a downcomer tube, D is a front evaporator heat transfer tube, E is a rear evaporator heat transfer tube, F is a primary superheater heat transfer tube, G is a secondary superheater heat transfer tube, H is a denitration device, and I is an exhaust cylinder. A heat transfer tube that performs heat exchange has a basically linear shape. The exhaust gas flows in one direction, and the exhaust cylinder having a single-section square cross section is in direct contact with the atmosphere. When such a conventional technique is applied as a waste heat boiler of a small-capacity heat cycle power generator,
The whole device becomes long, the connection of many small-diameter heat transfer tubes becomes complicated, and the wall surface inside the exhaust cylinder has a complicated structure. Further, it is necessary to attach a heat shield plate or a heat insulating material to the exhaust cylinder in which high-temperature exhaust gas flows inside to prevent heat dissipation and burns. If the exhaust gas contains a large amount of vapor components, a water film condenses or adheres to the outer surface of the tube. Some of the heat transfer tubes in the vertical direction are blown backward by the flow of exhaust gas, while others flow downward along the outer surface of the heat transfer tubes by gravity. For this reason, in the vertical heat transfer tube structure, a large amount of water film is easily formed on the outer surface of the tube, and the water film significantly impairs the heat exchange characteristics of the exhaust gas outside the tube and the water inside the tube. [0003] An object of the present invention is to provide a heat cycle power generation device using a small-capacity gas turbine device and a waste heat boiler device when the technology related to the conventional waste heat boiler device is applied. It is another object of the present invention to provide a simple and compact exhaust heat boiler that solves the above-mentioned problems. [0004] A steam generator according to the present invention is a heat cycle power generator using a gas turbine unit, a waste heat boiler unit, and a back pressure turbine unit (Japanese Patent Application No. 2000-2000).
FIG. 1 shows a structure in the case of applying the method to FIG. 1 is a prime mover, 2 is an air compressor, 3 is a combustor, 4 is a gas turbine stage, 5 is a steam turbine stage, 6 is a pump stage, 7 is a generator, 8 is an intake filter, and 9 is the present invention. Waste heat boiler device, 10 is {the outer cylinder of the annular cylindrical exhaust drum in the waste heat boiler device, 11} is the inner trunk, 12 is the {outermost trunk, 13} is the multi-spiral heat transfer tube group in the waste heat boiler device Is shown. FIG. 3 is a perspective view showing an overall three-dimensional image of the combined structure of the prime mover 1 and the exhaust heat boiler device 9. FIG. 4 is a perspective view showing a three-dimensional image of the multiple spiral heat transfer tube group. After cooling the generator 7, the water supply a from the lower part passes through the inside of the turbine shaft and is boosted in the pump stage 6.
It is guided to a pump discharge header 17 provided on the outer periphery of the prime mover 1. The high-pressure water b branched off by the header passes through each connecting pipe 18 inside the inner body 11, enters into the lower part of the annular cylindrical exhaust body, and is guided to each heat transfer pipe 13 having a different helical diameter.
The waste heat boiler device 9 according to the invention is of the once-through boiler type. The steam c exiting from each of the spiral heat transfer tubes 13 having an outlet at the upper portion of the annular cylindrical exhaust drum is guided to a steam header 19 provided on the outer periphery of the motor 1 through a connecting pipe 18 ′ inside the inner drum 11. On the other hand, the inner cylinder 1 of the annular cylindrical exhaust heat boiler device 9
Air d sucked from below into the prime mover 1 attached to the center of the vehicle 1 becomes high-temperature exhaust gas e containing a large amount of vapor components and is discharged above the prime mover 1. Immediately after the discharge, the flow of the exhaust gas e is reversed, and the heat transfer section 13 of the exhaust heat
Enter from above and discharge from below. The exhaust gas f is then reversed again and passes between the outer shell 10 and the outermost shell 12 and is discharged from above. The water film condensed on the surface of the helical heat transfer tube 13 easily blows down downward where the direction of gravity matches the flow of the exhaust gas, accumulates at the bottom of the annular exhaust drum, and is guided to the outside as a drain h. Here, the spiral heat transfer tubes 13 have different overall lengths and different pressure losses in the tubes. A throttle 14 is provided at the inlet of another heat transfer tube for the purpose of minimizing the difference in accordance with the pressure loss of the outermost heat transfer tube. Alternatively, the pressure loss of each heat transfer tube can be made uniform by increasing the diameter of the heat transfer tube on the outer peripheral side and decreasing the diameter of the heat transfer tube on the inner peripheral side. When the waste heat boiler device 9 according to the present invention is applied to a heat cycle power generation device using a gas turbine device, a waste heat boiler device, and a back pressure turbine device, the waste heat boiler device 9
Exhaust gas still contains vapor components. In order to further recover the latent heat, as shown in FIG. 5, cold water k is sprayed toward the exhaust gas g that has exited the perforated plate type tray 22 by the water injection device 21, and hot water is generated by direct contact heat exchange between the two. It is also effective to add a hot water generating device 20 for generating 1 to the end of the exhaust gas outlet of the exhaust heat boiler device 9. If such a direct contact type hot water generator 20 is used, effective heat recovery can be achieved with a small device. In addition, it is also possible to provide a large warm water reservoir 23 below the direct contact heat exchanger and also serve as a hot water storage tank. FIG. 3 shows an overall three-dimensional image of an embodiment of a waste heat boiler device 9 according to the present invention. FIG. 4 shows a three-dimensional image of the heat transfer tube group 13 and FIG. 6 shows an embodiment of a heat transfer portion of a double-pressure exhaust heat boiler device in a heat cycle power generation device whose heat cycle diagram is shown. The heat transfer tube group 13 is divided into two by a cylindrical partition plate 15 inserted between the heat transfer tube groups, high-pressure water b 'is passed through the outer heat transfer tube group 13', and low-pressure water b is passed through the inner heat transfer tube group 13 ''. '' Through. The exhaust gas e is branched off by a passage 16 provided at an appropriate position in the axial direction (FIG. 3 shows a case of branching at the most upstream portion), and flows downward. The pipe arrangement on the meridional section of the exhaust heat boiler device 9 according to the present invention can be any of a grid arrangement and a staggered arrangement. In FIG. The low-pressure heat transfer tube groups 13 "are arranged in a grid pattern. When applying the present invention as the waste heat boiler device 9 for cogeneration, when high temperature steam is required, the steam is taken out from the middle of the heat transfer tube or the connection tube at the boiler outlet or from the turbine inlet steam header 19. When the exhaust heat boiler device 9 according to the present invention is applied to a heat cycle power generation device using a gas turbine device, an exhaust heat boiler device, and a back pressure turbine device, steam emitted from the exhaust heat boiler device 9 at the time of starting and stopping the device. Providing a switching valve downstream of the steam header so that water can bypass the prime mover is effective for smooth operation. In addition, in order to prevent scales from adhering to the heat transfer tubes during operation and to prevent heat transfer characteristics from deteriorating, it is desired to use water that has been appropriately treated with water. In the case where no chemical components contained in the combustion gas are mixed into the hot water supply, a hot water generator using multiple spiral heat transfer tubes is used instead of a direct contact heat exchanger as shown in FIG. It is also possible to mount them in series or in parallel at the lower part of the heat tube group. However, compared with the case of using the direct contact heat exchanger shown in FIG. 5, an increase in the volume of the heat transfer section is inevitable. If fluid-related vibration of the tube group is a problem, the vibration is suppressed by a support plate having circular holes oriented in the radial direction and corresponding to the arrangement of the heat transfer tubes at appropriate locations on the circumference of the annular cylindrical exhaust drum. be able to.
The mounting of the support plate is performed while rotating each of the spiral heat transfer tubes with respect to the support plate. According to the present invention, a reasonable heat transfer tube group 13 is provided.
Thereby, a simple small heat exchanger having a heat transfer surface density (heat transfer area / volume) of 800 (1 / m) or more is obtained. This value is the shell and tube type heat transfer surface density of 70 to 120.
Also, it greatly exceeds the plate type heat transfer surface density of 150 to 300, and is comparable to the value of a compact heat exchanger having a complicated structure of a fin-and-tube type or a corrugated fin type. When the present invention is applied to a cogeneration apparatus having a power generation capacity of a 40 kW class, its general outer dimensions are a cylindrical shape having a diameter of 400 mm and a height of 400 mm, which is several times smaller than that of a conventional machine having the same capacity. When the present invention is applied to a heat cycle power generation device using a waste heat boiler device, a gas turbine device, and a back pressure turbine device, by disposing the prime mover 1 and the generator 7 at the center of the waste heat boiler device 9, All the components of the apparatus can be easily integrated. In addition, the prime mover 1 is disposed at the center of the exhaust heat boiler device 9, and heat radiation from the prime mover 1 is
This structure, which is re-used, together with the structure in which the low-temperature exhaust gas f flows inside the outermost body 12, significantly reduces the heat dissipation loss in the entire heat cycle. In addition, the low temperature of the outermost body 12 eliminates the need for a heat shield plate and a heat insulating member for preventing burns, and prevents an increase in the outer dimensions due to these. Further, for the prime mover 1 assembled on the same central axis as the exhaust heat boiler device 9, since the exhaust heat boiler device 9 has axial symmetry in temperature distribution and the like, non-uniform deformation based on axial asymmetry in external conditions is prevented. Therefore, there is an advantage that the gap between the rotating part and the stationary part can be reduced. Further, a waste heat boiler device 9 arranged on the outer periphery of the prime mover 1
Absorbs the kinetic energy of the fragments in the event that the rotating part of the motor 1 is broken, thereby preventing the fragments from scattering outside. Further, the absence of the contact portion between the exhaust body and the heat transfer tube group as the structure of the exhaust heat boiler device 9 eliminates the stress generation due to the difference in thermal expansion between the two and the trouble related to the sealing of the exhaust gas. In addition, this structure, which does not have a complicated header or header near the heat transfer tube group, facilitates cleaning of scale and scale and improves maintainability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a structural cross-sectional view when a steam generator 9 according to the present invention is applied to a heat cycle power generator using a gas turbine device, a waste heat boiler device, and a back pressure turbine device. [Claims 1] to [Claim 5] are shown. FIG. 2 is a structural cross-sectional view of a typical exhaust heat boiler device constituting a conventional power generation device. FIG. 3 is a perspective view showing an overall three-dimensional image of a combined structure of a prime mover 1 and an exhaust heat boiler device 9. 4 is a perspective view showing a three-dimensional image of the multi-spiral heat transfer tube group 13 and a three-dimensional image of a detailed embodiment of the double-pressure exhaust heat boiler device. FIG. 5: Spraying cold water and generating hot water by direct contact heat exchange with exhaust gas. The principle of the device 20 is shown in the following claims. FIG. 6 is a heat cycle diagram of a heat cycle power generation device using a double-pressure exhaust heat boiler device, a gas turbine device, and a back pressure turbine device [Description of References] 1 is a prime mover, 2 is an air compressor, and 3 is仝 Combustor, 4 仝 Gas turbine stage, 5 仝 Steam turbine stage, 6 ポ ン プ Pump stage, 7 発 電 Generator, 8 排 Intake filter, 9 排 Waste heat boiler device according to the present invention, 仝 10 仝 Waste heat boiler device , The outer cylinder of the annular cylindrical exhaust cylinder, 11 is the inner cylinder, 12 is the outermost cylinder, 13 is the multi-spiral heat transfer tube group in the exhaust heat boiler, 13 ′ is the high pressure heat transfer tube, and 13 ″ is the low pressure Heat transfer tube, 1
4 is a throttle mechanism for adjusting pressure loss, 14 'is a throttle mechanism for a low-pressure heat transfer tube, 15 is a partition plate, 16 is a branch passage provided in the partition plate, 17 is a pump discharge header, and 18 is a pump discharge header and a heat transfer tube. A connecting pipe, 18 'is a connecting pipe between the heat transfer pipe and the steam header, 19 is a steam header, 20 is a hot water generator, 21 is a water jetting apparatus, 22 is a perforated plate tray, and 23 is a hot water reservoir.
a is the feed water to the pump device, b and b 'are the feed water pressurized by the pump device, b''is the feed water depressurized by the throttle 14', c is the steam generated in the exhaust heat boiler device, d is the intake air of the prime mover, e is exhaust gas discharged from the prime mover, f is exhaust gas discharged from the heat transfer boiler heat transfer tube, g is exhaust gas discharged from the upper outlet of the annular cylindrical heat boiler, and h is lower part of the annular cylindrical heat boiler. Drain to drain, i
Denotes fuel gas supplied to the gas compressor, j denotes electric power generated by the generator, k denotes water supply to the hot water generator, and l denotes hot water taken out from the hot water generator. A is an economizer heat transfer tube in a conventional large-sized waste heat boiler device. Similarly, B is a steam drum, C is a downcomer, D is a front evaporator heat transfer tube, E is a rear evaporator heat transfer tube, F is a primary superheater heat transfer tube, G is a secondary superheater heat transfer tube, H is a denitration device, I is an exhaust cylinder.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F22B 1/18 F22B 1/18 K 27/04 27/04 A F24H 1/00 631 F24H 1/00 631D F28C 3/08 F28C 3/08

Claims (1)

The present invention relates to a shell and tube heat exchanger for generating steam by heating water in a tube by exhaust gas outside the tube, wherein a plurality of heat transfer tubes are formed in a spiral shape having the same pitch and different spiral diameters. A device in which the heat transfer tubes are arranged in multiple concentric circles so as to be housed between an outer cylinder and an inner cylinder of an annular cylindrical exhaust cylinder. 2. A pump arranged inside an inner cylinder in claim 1. Apparatus for directly connecting the discharge header and the inlet of each heat transfer tube to the steam header of the turbine inlet and the outlet of each heat transfer tube. 3. The apparatus according to claim 2, wherein the pressure loss in each tube approaches the same. A device for installing an orifice in a heat transfer tube or a connection tube with a header, or a device having a function of squeezing a local portion of a heat transfer tube or a connection tube and restricting a flow in the tube. And circular circle 5. A device in which the central axis of the cylinder exhaust cylinder is oriented vertically. 5. The high-temperature exhaust gas of a prime mover arranged inside the inner cylinder is taken in from the upper part of the device, and heat exchange in the heat transfer tube is completed. An apparatus for inverting exhaust gas discharged downward at a lower portion of the apparatus, flowing upward between an outer body and an outermost body disposed further outside the outer body, and discharging the exhaust gas from above. 6. An apparatus for generating cold water by spraying cold water into exhaust gas which has been subjected to heat exchange according to claim 1, and by direct contact heat exchange with the exhaust gas.