WO2014110881A1

WO2014110881A1 - Pellet fuel boiler equipped with regenerative rotating commutating heater

Info

Publication number: WO2014110881A1
Application number: PCT/CN2013/075694
Authority: WO
Inventors: 吴道洪; 陈琳; 鲁光明; 吴玉林; 王胜美; 沈大平
Original assignee: 北京神雾环境能源科技集团股份有限公司
Priority date: 2013-01-18
Filing date: 2013-05-16
Publication date: 2014-07-24
Also published as: ZA201505204B; RU2612680C2; RU2015133245A; AU2013374014A1; AU2013374014B2

Abstract

A pellet fuel boiler (100) equipped with a regenerative rotating commutating heater. The pellet fuel boiler (100) comprises a hearth (11), a regenerative rotating commutating heater (2), a fume passage (3), and an air passage (4). The regenerative rotating commutating heater (2) comprises a heat exchanger main body (21), a driving device, a partition member (22), and heat carriers (23). An inlet end of the fume passage (3) is communicated with a top portion of the hearth (11), and an outlet end of the fume passage (3) is communicated with the regenerative rotating commutating heater (2), so that fume is delivered into one of at least paired accommodating portions (25) of the heat exchanger main body (21) and exchanges heat with the heat carrier (23) accommodated in the accommodating portion (25). The air passage (4) is used for delivering air at least into the other one of the paired accommodating portions (25) of the heat exchanger main body (21), so that the heat carrier (23) accommodated in the accommodating portion (25) exchanges heat with air, and the air after heat exchange is supplied into the hearth (11). The pellet fuel boiler (100) can recycle sensible heat and latent heat in the fume to the maximum extent, thereby improving thermal efficiency of the boiler.

Description

Pellet fuel boiler equipped with regenerative rotary reversing heater

The present invention relates to the field of heat exchange technology, and more particularly to a particulate fuel boiler equipped with a regenerative rotary reversing heater. Background technique

Circulating fluidized bed boiler technology, originally a combustion process technology in the chemical industry, was used in the 1975 German Luqi company for boiler combustion. In 1979, Finland produced the first 20 ton/hour commercial circulating fluidized bed boiler, which has been used in the power industry. In China, there are more than 3,000 circulating and more than 100 MW circulating fluidized bed boilers. The world has the largest number of circulating fluidized bed boilers.

Circulating popularized bed boiler technology is a highly efficient and low-pollution clean combustion technology that has developed rapidly in the past decade. This technology has been widely used in power plant boilers, industrial boilers, and waste treatment and utilization, and has been developed for large circulating fluidized bed boilers of several hundred thousand kilowatt scale. The future will also be an important period for the rapid development of circulating fluidized beds.

In order to improve efficiency, the existing circulating fluidized bed boiler is provided with an air preheater at the flue gas discharge port and the air inlet to heat the air preheater through the flue gas, and the air preheater enters the air inlet freshly. The air is heated again. However, in the prior art, the temperature of the flue gas after heating the air preheater must be controlled above 130 ° C. If the temperature is lower than 130 ° C, the dew point of sulfur will be reached, which will cause acid corrosion to the air preheater. The air preheater is damaged, so the fresh air entering the intake port cannot fully recover the sensible heat and latent heat in the flue gas. Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art.

Accordingly, it is an object of the present invention to provide a particulate fuel boiler equipped with a regenerative rotary reversing heater which can maximize the recovery of sensible heat in the flue gas. And latent heat.

According to a first aspect of the present invention, there is provided a particulate fuel boiler equipped with a regenerative rotary reversing heater, wherein the particulate fuel boiler equipped with a regenerative rotary reversing heater comprises: a furnace; a regenerative type a reversing reversing heater, the regenerative rotary reversing heater comprising: a heat exchanger body; a driving device, wherein the driving device is configured to drive the heat exchanger body to rotate about a central axis thereof; a partition member disposed in the heat exchanger body along a direction of the central axis, and partitioning the heat exchanger body into at least one pair of receiving portions, the pair of receiving portions being radially opposite to the central axis a heat carrier, the heat carrier is respectively accommodated in the accommodating portion, the heat carrier is formed of a non-metallic solid material; a flue gas passage, an inlet end of the flue gas passage is connected to a top of the furnace And the outlet end is in communication with the regenerative rotary reversing heater to pass the flue gas generated in the furnace into at least one of the pair of the receiving portions and The heat carrier accommodated heat exchange; an air passage for introducing at least air into the other of the pair of the receiving portions to allow the heat carrier to be accommodated therein The heat is exchanged with the air, and the air after the heat exchange is supplied to the inside of the furnace.

According to the pellet fuel boiler equipped with the regenerative rotary reversing heater according to the embodiment of the present invention, the high temperature generated by the particulate fuel boiler equipped with the regenerative rotary reversing heater can be provided by providing the regenerative rotary reversing heater The flue gas is reduced to 65-75 °C, which improves the efficiency of the boiler. Since the regenerative rotary reversing heater absorbs and absorbs heat by rotation, the heating efficiency is improved and the heat loss is reduced. cost.

Further, the particulate fuel boiler equipped with the regenerative rotary reversing heater according to the present invention has the following additional technical features:

According to an embodiment of the present invention, the flue gas passage includes a tail flue communicating with the furnace and a hot flue flue communicating with the tail flue, the outlet end of the hot flue and the storage The hot rotary reversing heater is connected.

Optionally, a plurality of superheaters are disposed in the tail flue. Thus, by providing a superheater, the cycle thermal efficiency of the entire steam power unit can be effectively improved.

According to an embodiment of the present invention, the particulate fuel boiler equipped with the regenerative rotary reversing heater further includes: a cyclone separator, wherein the cyclone separator is respectively connected to the top of the furnace and the tail flue . Therefore, by providing the cyclone separator, the flue gas and the larger particulate fuel and the ash particles can be effectively separated.

Further, the cyclone separator further includes a return pipe that communicates with the main body of the cyclone and the lower portion of the furnace, respectively. Thus, by providing a return pipe, larger particulate fuel and ash particles can pass through the return pipe, circulate into the furnace combustion and heat exchange.

According to an embodiment of the invention, the flue gas velocity entering the regenerative rotary reversing heater from the hot flue is adjustable. Thereby, the temperature of the air to be preheated is effectively increased.

Optionally, the heat carrier is SiC or ceramic. Thus, the regenerative rotary reversing heater is resistant to high temperatures, corrosion and wear.

Alternatively, the heat carrier has a structure of a small spherical shape, a sheet shape or a porous shape.

Optionally, the temperature of the flue gas after heat exchange by the regenerative rotary commutation heater is 65-75 °C.

Optionally, the particulate fuel combusted in the furnace has a diameter of from 0.5 to 13 mm.

Optionally, a catalyst for catalyzing NOx is added to the heat carrier.

The additional aspects and advantages of the invention will be set forth in part in the description which follows. DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the construction of a particulate fuel boiler equipped with a regenerative rotary reversing heater according to an embodiment of the present invention.

2 is a top plan view of a regenerative rotary reversing heater in a pulverized solid fuel boiler in accordance with an embodiment of the present invention. detailed description

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative only and not to limit the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "previous", "post", "left", "right", " The orientation or positional relationship of the indications "upright", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and The simplification of the description is not intended to limit or imply that the device or elements referred to have a particular orientation, construction and operation in a particular orientation. Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Further, in the description of the present invention, "multiple" means two or more unless otherwise stated.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" should be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or connected integrally; can be mechanical or electrical; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of the two components. The specific meaning of the above terms in the present invention can be understood in a specific case by those skilled in the art.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of the specific examples are described below. Of course, they are merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numerals and/or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not in itself indicate the relationship between the various embodiments and/or arrangements discussed. Moreover, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the applicability of other processes and/or the use of other materials.

Additionally, the structure of the first feature described below "on" the second feature may include embodiments in which the first and second features are formed in direct contact, and may include additional features formed between the first and second features. The embodiment, such that the first and second features may not be in direct contact.

A particulate fuel boiler 100 equipped with a regenerative rotary reversing heater according to an embodiment of the present invention will now be described with reference to FIG.

As shown in Fig. 1, a particulate fuel boiler equipped with a regenerative rotary reversing heater according to an embodiment of the present invention includes: a furnace 11, a regenerative rotary reversing heater 2, a flue gas passage 3, and an air passage 4.

The regenerative rotary reversing heater 2 is used for exchanging heat between the high temperature flue gas and the air to be preheated, thereby raising the temperature of the air to be preheated to a certain value. The regenerative rotary reversing heater 2 comprises: a heat exchanger body 21, a driving device, a partition 22 and a heat carrier 23, as shown in Figs. The drive means is for driving the heat exchanger body 21 to rotate about its central axis 24. The partition 22 is disposed in the heat exchanger body 21 in the direction of the central axis 24, and divides the heat exchanger body 21 into at least one pair of accommodating portions 25, each pair of accommodating portions 25 being disposed diametrically opposite to the central axis. The heat carriers 23 are respectively accommodated in the accommodating portion 25, and the heat carrier 23 is formed of a non-metallic solid material. Root According to an embodiment of the present invention, a catalyst for catalyzing NOx is added to the heat carrier, thereby enabling the boiler process to reduce NOx, and at the same time eliminating existing catalysts by providing a catalyst for catalyzing NOx in the heat carrier. The NOx removal unit must be separately installed at the flue gas outlet, thereby increasing the efficiency of the entire system while reducing costs.

In one of the examples of the present invention, the heat exchanger body 21 may be formed as a hollow cylinder, and the partition 22 may be substantially plate-shaped, and the partition extends in the direction of the center line axis of the heat exchanger body 21, thereby The heat exchanger body 21 is partitioned into a pair of receiving portions, the heat carriers are respectively disposed in the two receiving portions, and the heat carrier can be made of a non-metallic solid material, and the flue gas and the air to be preheated are respectively introduced into the two receiving portions, and then passed through The driving device drives the heat exchanger main body 21 to rotate, the flue gas exchanges heat with the heat carrier in the accommodating portion in which it is located, heats the air to be preheated, and the heat carrier in the accommodating portion therewith, thereby causing the air to be preheated The temperature rises.

Of course, the invention is not limited thereto, and in other examples of the invention, the partition 22 may also divide the heat exchanger body 21 into two pairs, three pairs or even pairs of receiving portions.

In the existing gas heat exchange system, the outlet temperature of the flue gas after passing through the gas heat exchanger cannot be lowered below 130 ° C, because this leads to the deposition of sulfur, thereby causing the gas heat exchanger to be Severe corrosion of parts made of metal. However, in the above-described regenerative rotary commutation heater 2 of the present invention (for, for example, high-temperature flue gas containing sulfur), since the heat carrier is formed of a non-metallic solid material such as SiC or ceramic, there is no need to worry about sulfur. At 130 ° C, there is a problem of corrosion caused by the dew point, and the outlet temperature of the high-temperature flue gas can be lowered to a temperature below the dew point of sulfur to maximize heat exchange. According to an embodiment of the present invention, the high temperature The outlet temperature of the flue gas leaving the gas heat exchanger is less than 130 ° C. Further, the outlet temperature of the high temperature flue gas leaving the gas heat exchanger is less than 70 ° C. This temperature is almost impossible to achieve in a conventional gas heat exchange system. In addition, below the temperature at which the outlet temperature is lowered to the dew point, the sulfur changes from a gas to a solid, releasing a large amount of latent heat (equivalent to three times the amount of heat absorbed from 0 ° C to 10 CTC). Since the heat carrier is formed of a non-metallic solid material, after the sulfur deposition is performed to some extent, the heat carrier accommodated in the accommodating portion can be continuously used, thereby reducing the components existing in the conventional gas heat exchange system. The problem of increased costs caused by replacement. Further, according to the calculation by the inventor, by carrying the regenerative rotary reversing heater, the cold air is heated to the hot air to facilitate the combustion, and the exhaust gas temperature is lowered to 65 to 75 ° C, effectively utilizing the waste heat of the fuel, and Increase the efficiency of the boiler by more than 3 percentage points.

The particulate fuel boiler 100 equipped with a regenerative rotary reversing heater defines a furnace 11 . The inlet end of the flue gas passage 3 communicates with the top of the furnace 11 and the outlet end communicates with the regenerative rotary reversing heater 2 to pass the flue gas generated in the furnace 11 into at least a pair of regenerative rotations. One of the accommodating portions of the reversing heater 2 is exchanged with the heat carrier accommodated in the accommodating portion. The air passage 4 is for introducing at least the air into the other of the pair of accommodating portions so that the heat carrier accommodated in the accommodating portion exchanges heat with the air, and the heat-exchanged air is supplied to the inside of the furnace 11. The heat exchanged by the regenerative rotary commutator heater 2 flows out through the second flue gas passage 101.

In the following description, the heat exchanger body 21 is rotated counterclockwise, and the flue gas is introduced into the heat exchanger body 21 along the right side of the central axis, and the preheated air is introduced into the heat exchanger along the left side of the central axis. The main body 21 will be described as an example.

As shown in FIG. 1, a furnace 11 is defined in the boiler body 1 for accommodating particulate fuel having a diameter of 0.5-13 mm, one end of the flue gas passage 3 is communicated with the furnace 11, and the other end is connected with a regenerative rotary reversing heater. 2 communication, to the furnace The flue gas generated in the crucible 11 is introduced into the first accommodating portion 211 of the regenerative rotary reversing heater 2 (for example, the right side of the regenerative rotary reversing heater 2 shown in Fig. 1), and the heat storage is performed. In the second accommodating portion 212 of the rotary reversing heater 2 (for example, the left side of the regenerative rotary reversing heater 2 shown in Fig. 1) for introducing air to be preheated, in the heat exchanger body When the motor 21 is in the unrotated state, the flue gas exchanges heat with the heat carrier in the first accommodating portion 211 to raise the temperature of the heat carrier, and after the heat carrier absorbs heat, the heat exchanger body 21 rotates counterclockwise, and the first accommodating portion 211 Rotating to the left side of the central axis, the second receiving portion 212 is rotated to the right side of the central axis, and the heat carrier rotating into the first receiving portion 211 on the left side exchanges heat with the air to be heated to raise the temperature of the heated air. At the same time, the flue gas heats the heat carrier rotating into the second accommodating portion 212 on the right side.

The heat exchanger body 21 continues to rotate counterclockwise, at which time the first receiving portion 211 is rotated back to the right side of the central axis, the second receiving portion 212 is rotated back to the left side of the central axis, and rotated back to the second accommodation on the left side. The heat carrier in the portion 212 exchanges heat with the air to be heated, and the flue gas heats the heat carrier in the first accommodating portion 211 which is rotated back to the right side, and the cycle is repeated to complete the heating of the preheated air.

In an example of the present invention, the preheated air is heated to a certain temperature and can be supplied into the furnace 11 from the bottom of the particulate fuel boiler 100 carrying the regenerative rotary reversing heater, thereby performing the pellet fuel in the furnace 11 At high temperature oxidative combustion, particulate fuel can enter the furnace 11 from the fuel inlet 13.

Further, the bottom of the particulate fuel boiler 100 equipped with the regenerative rotary reversing heater is provided with a wind deflecting plate 12, and the preheated air enters the furnace 11 through the air distribution plate 12 at the bottom of the boiler. The flue gas after heat exchange with the preheated air is discharged through the exhaust passage 101.

According to the particulate fuel boiler 100 equipped with the regenerative rotary reversing heater according to the embodiment of the present invention, the regenerative rotary reversing heater 2 can reduce the high temperature flue gas to 70 by providing the regenerative rotary reversing heater 2 Around °C, which improves the efficiency of the boiler.

As shown in Fig. 1, the flue gas passage 3 includes a tail flue 31 communicating with the furnace 11 and a hot flue duct 32 communicating with the tail flue 31. The outlet end of the hot flue duct 32 and the regenerative rotary reversing heating The devices 2 are connected. That is, the flue gas passage 3 includes a tail flue 31 and a hot flue duct 32, wherein one end of the tail flue 31 communicates with the furnace 11, and the other end thereof communicates with the hot flue 32, and the other end of the hot flue 32 The outlet end communicates with the regenerative rotary reversing heater 2.

Optionally, a plurality of superheaters 311 are disposed within the tail flue 31. In other words, a plurality of superheaters 311 spaced apart from each other can be provided in the tail flue 31. Thus, by providing the superheater 311, the cycle thermal efficiency of the entire steam power unit can be effectively improved.

In one embodiment of the present invention, the particulate fuel boiler 100 equipped with the regenerative rotary reversing heater further includes: a cyclone separator 6, and the cyclone separator 6 is in communication with the top and tail flues 31 of the furnace 11, respectively. For example, in the example of Fig. 1, a cyclone separator 6 is provided at the junction of the furnace 11 and the tail flue 31, and communicates with the furnace 11 and the tail flue 31, respectively. Thereby, the flue gas and the larger particulate fuel and the ash particles can be effectively separated by providing the cyclone separator 6.

Further, the cyclone separator 6 further includes a return pipe 61 that communicates with the main body of the cyclone separator 6 and the lower portion of the furnace 11 respectively. As shown in FIG. 1, one end of the return pipe 61 and the bottom of the cyclone separator 6 The other end is in communication with the lower portion of the furnace 11. Thus, by providing the return pipe 61, the larger particulate fuel and ash particles can pass through the return pipe 61, circulate into the furnace 11 for combustion and heat exchange.

In one embodiment of the invention, the velocity of the flue gas entering the regenerative rotary reversing heater 2 from the hot air flue 32 is adjustable. When the velocity of the flue gas entering the regenerative rotary reversing heater 2 from the hot flue flue 32 is high, the temperature of the air to be preheated can be greatly increased.

Alternatively, the heat carrier is SiC or ceramic and has a small spherical, sheet-like or porous structure. Thus, the regenerative rotary reversing heater 2 is resistant to high temperatures, corrosion, and wear.

Alternatively, the temperature of the flue gas after heat exchange by the regenerative rotary commutator heater 2 is 65-75 ° C, thereby greatly improving the efficiency of waste heat recovery.

In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples", etc. Particular features, structures, materials or features described in the examples or examples are included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

While the embodiments of the present invention have been shown and described, the embodiments of the invention may The scope of the invention is defined by the claims and their equivalents.

Claims

claims

1. A pellet fuel boiler equipped with a regenerative rotary reversing heater, which is characterized by including: a furnace;

Regenerative rotary reversing heater, the regenerative rotary reversing heater includes:

Heat exchanger body;

A driving device, the driving device is used to drive the heat exchanger body to rotate around its central axis; a partition, the partition is arranged in the heat exchanger main body along the direction of the central axis, and moves the The heat exchanger body is divided into at least one pair of receiving parts, and each pair of receiving parts is arranged radially opposite to the central axis;

Heat carriers, the heat carriers are respectively accommodated in the accommodation parts, the heat carriers are formed of non-metallic solid materials;

Flue gas passage, the inlet end of the flue gas passage is connected with the top of the furnace, and the outlet end is connected with the regenerative rotary reversing heater, so as to pass the flue gas generated in the furnace into at least within one of the pair of accommodation parts and exchanging heat with the heat carrier accommodated therein;

Air passage, the air passage is used to pass air into at least the other one of the pair of accommodation parts, so that the heat carrier accommodated therein can exchange heat with the air. After heat exchange, of air is supplied to the interior of the furnace.

2. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 1, wherein the flue gas passage includes a tail flue connected to the furnace and a tail flue connected to the tail flue. There is a connected hot air flue, and the outlet end of the hot air flue is connected with the regenerative rotary reversing heater.

3. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 2, characterized in that multiple superheaters are provided in the tail flue.

4. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 3, further comprising: a cyclone separator, the cyclone separator is connected to the top and the tail of the furnace respectively. The flues are connected.

5. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 4, wherein the cyclone separator further includes a return pipe, and the return pipe is connected to the cyclone separator respectively. The main body and the lower part of the furnace are connected.

6. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 2, characterized in that the speed of the flue gas entering the regenerative rotary reversing heater from the hot air flue can be adjust.

7. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 1, wherein the heat carrier is SiC or ceramic.

8. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 1, characterized in that the temperature of the flue gas after heat exchange by the regenerative rotary reversing heater is 65-75 °C.

9. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 8, characterized in that the diameter of the pellet fuel burned in the furnace is 0.5-13mm.

10. The pellet fuel boiler equipped with a regenerative rotary reversing heater according to claim 1, characterized in that a catalyst for catalyzing NOx is added to the heat carrier.