CN214172216U - Double-flue circulating fluidized bed boiler flue structure - Google Patents

Abstract

The utility model discloses a two double flue circulating fluidized bed boiler flue structures, a serial communication port, include two independent flue gas passageways that divide with the boiler central line, every flue gas passageway is inside to be split into 2n sub-flue gas passageways by the partition wall, the flue gas passageway import is the cyclone export, cyclone quantity is the even number. The utility model has flexible structure and wide application range; the installation and transportation are convenient, the operation is easy, and the deformation under the action of gravity is not easy to generate; the operation control is simple, and the operation cost is effectively reduced; the design of the circulating fluidized bed boiler can adapt to various parameters.

Description

Double-flue circulating fluidized bed boiler flue structure

Technical Field

The utility model relates to a two double flue circulating fluidized bed boiler flue structures belongs to circulating fluidized bed boiler technical field.

Background

The circulating fluidized bed boiler has the characteristics of wide fuel application range, low pollution emission and the like, is widely applied to various industries, is continuously developed towards large-scale direction for obtaining higher energy utilization rate, and needs to be correspondingly adjusted in structure for meeting the requirement.

As shown in fig. 1 and 2, the flue gas is generated by combustion in a furnace and then separated in a cyclone separator 1, the fully combusted flue gas rises to a flue gas channel 2 at the outlet of the cyclone separator due to the reason of small granularity and the like, the flue gas is concentrated to a flue gas channel 3 of a rear flue pipe through one or N (N is more than or equal to 2) flue gas channels at the outlet of the cyclone separator, and a membrane type heating surface or an internal coiled pipe heating surface of the wall of the flue gas channel 3 of the rear flue pipe is heated to further absorb heat in the flue gas. Along with the increase of the parameters of the circulating fluidized bed, the fuel is increased, the number of the cyclone separators is correspondingly increased, and if the flue gas channel of the rear smoke well is simply amplified, the width of the flue gas channel is far larger than that of the required convection flue gas channel, so that larger flue gas side deviation is caused in the range of a coating area. Therefore, the flue gas channel structure of the conventional circulating fluidized bed rear smoke well has certain limitation.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: the traditional smoke channel structure of the rear smoke well has the condition that the width of a single smoke channel structure (connected with outlets of all cyclone separators) is inconsistent with the width of a convection smoke channel required by thermodynamic calculation as the capacity of a boiler is increased; the width of a single flue gas channel is too large, the limitation of soot blower arrangement is increased, the possibility that the hot surface of a rear smoke well is heated unevenly is increased, and the size of the smoke temperature baffle at the tail of the single flue gas channel is higher in requirement and more difficult to operate. In summary, the single flue gas channel of the conventional circulating fluidized bed has limitations.

In order to solve the technical problem, the technical scheme of the utility model a double flue circulating fluidized bed boiler flue structure is provided, the design is nimble, the operation is reliable, the regulation performance is good, application scope is wider, the necessary waterwall furnace of traditional boiler, the air distributor, cyclone and feed back ware's structure is unchangeable, the flue structure specifically is two independent flue gas passageways that use the boiler central line to divide, whether two or more sub-flue gas passageways can be split into by the partition wall to every flue gas passageway inside can be selected as required. Each flue gas channel inlet of the double-double flue circulating fluidized bed boiler is a cyclone separator outlet, the cyclone separator outlet can be reasonably combined with two flue gas channel inlets of the double-double flue according to the number, the position and the like of the cyclone separators, for example, a single flue gas channel inlet smoke window enters the flue gas channel inlet smoke window, two flue gas channel inlet smoke windows enter the flue gas channel inlet smoke window after being converged, and the like, and two independent flue gas channels in the double-double flue represent on a flue gas channel wall body formed by independent pipes or steel plates in each channel, so that the circulation range of the flue gas is limited, and the flue gas is prevented from overflowing and leaking ash.

Preferably, the number of cyclones is even.

Preferably, the number of the cyclone separators is even times of the number of the independent flue gas channels, the cyclone separators are divided into two groups which are respectively arranged at the front side and the rear side of the boiler furnace, and outlets of the cyclone separators which are positioned at the front side and the rear side are connected in parallel and communicated and then connected to the nearest inlet of the flue gas channel.

Preferably, the inlet of the flue gas channel is a horizontal inlet.

Preferably, independent coiled pipe heating surfaces, expansion joints, manhole doors, soot blowers, flue gas baffles, air preheaters and draught fans are arranged in the two independent flue gas channels from inlets to outlets.

The utility model has two independent flue gas channels, so the size of the flue gas channel is less limited by the structure and can be determined according to the width of the convection flue gas channel which is actually needed, thus the angle alpha of the inlet flue gas channel of the smoke well is more flexible to take and the soot blower is more flexible to arrange; each independent flue gas channel is separated into two flue gas channels by a partition wall (the form of the partition wall and the position in the system are determined according to design requirements), and the heating surfaces of a coil pipe such as a superheater, a reheater and an economizer can be arranged in the range of each flue gas channel; the sizes of the flue gas baffle plate, the air preheater and the like at the tail part of each independent flue gas channel can be changed corresponding to the size of the flue gas channel, so that the aims of adjusting the temperature and sending air into the flue gas channel for preheating are fulfilled.

The utility model has flexible structure and wide application range; the installation and transportation are convenient, the operation is easy, and the deformation under the action of gravity is not easy to generate; the operation control is simple, and the operation cost is effectively reduced; the design of the circulating fluidized bed boiler can adapt to various parameters.

The utility model discloses the advantage is in the width of the two flues of afterbody that significantly reduces, reduces because the unreliable factor that the width brought is favorable to arranging of soot blower, improves boiler reliability.

Drawings

Fig. 1 and 2 are schematic structural views of a conventional circulating fluidized bed sheet flue, wherein fig. 1 is a front view and fig. 2 is a top view;

fig. 3 and 4 are schematic diagrams of a double-double flue structure of a circulating fluidized bed, wherein fig. 3 is a front view and fig. 4 is a top view;

fig. 5 is a front view of a variant of the inlet of the double flues of the circulating fluidized bed.

Detailed Description

In order to make the present invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.

The utility model relates to a double-double flue circulating fluidized bed boiler flue structure, used as the flue gas channel after the circulating fluidized bed cyclone separator export, in the embodiment as shown in figure 3 and figure 4, N is 4 cyclone separators 1 which are arranged between a furnace and a back smoke well, after the flue gas is separated by the cyclone separators in thickness, the flue gas with complete combustion and fine particles enters the smoke gas channel 3, 3 'of the back smoke well from the outlet flue gas channel 2 at the top end of the cyclone separator, two independent flue gas channels 3 and 3' are respectively arranged at the two sides of the central line of the boiler in the figure, the size is determined by thermodynamic calculation and the like, after the structure is arranged, the flue gas channel 2 at the outlet of the cyclone separator can be respectively introduced into two independent flue gas channels 3 and 3 'in a group under the condition that the angle alpha is 0 degree, the flue gas distribution is more uniform when the angle alpha is smaller and the back smoke well is horizontally introduced into the double-flue gas channels 3 and 3', the smaller the deviation of the smoke temperature of each part, the closer each part can be to the theoretical design value, and therefore, the maximum angle of the angle alpha is not more than 45 degrees. Boiler components and matching parts such as a coiled pipe heating surface, an expansion joint, a manhole door, a soot blower, a flue gas baffle, an air preheater, an induced draft fan and the like can be respectively arranged in the two independent flue gas channels 3 and 3 ', when boiler parameters become large, heating surfaces of different types such as a superheater and a reheater need to be arranged at positions on the boiler, and heat is more easily and reasonably distributed after being divided into small blocks, so that partition walls 4 and 4 ' are added in the two independent flue gas channels 3 and 3 ' to divide the two independent flue gas channels into two sub-flue gas channels, the proportion of the positions of the partition walls, namely H1 and H2, can obtain an optimal solution according to calculation, and the partition height of the partition walls can obtain the optimal solution according to the flue gas mixing degree and the like.

In the double-flue circulating fluidized bed boiler structure, the inlet and the outlet of the flue gas channel can be designed into different forms according to the needs, for example, in fig. 5, half of each cyclone separator, N-8, is respectively arranged at the front and rear positions of the furnace, and the outlet flue gas channels of the cyclone separators at the front and rear walls can be merged into the inlet of the flue gas channel at the rear flue; the outlets of the flue gas channel, such as a slag discharge port, an air preheater, a blower and the like, can also be arranged independently or combined according to the requirements.

Claims (6)

1. The utility model provides a two double flue circulating fluidized bed boiler flue structures, its characterized in that, the flue includes two independent flue gas passageways that divide with the boiler central line, and every flue gas passageway is inside to be divided into 2n sub-flue gas passageways by the partition wall, and n is the natural number, flue gas passageway inlet connection cyclone export.

2. The dual-flue circulating fluidized bed boiler flue structure of claim 1, wherein two independent flue gas channels share a central wall.

3. The dual double flue circulating fluidized bed boiler flue structure of claim 1, wherein the number of cyclones is an even number.

4. The dual-flue circulating fluidized bed boiler flue structure of claim 3, wherein the number of the cyclone separators is even times of the number of the independent flue gas channels, the cyclone separators are divided into two groups which are respectively arranged at the front side and the rear side of the boiler furnace, and outlets of the cyclone separators which are positioned at the front side and the rear side are connected in parallel and communicated with each other and then connected to the nearest inlet of the flue gas channel.

5. The dual-flue circulating fluidized bed boiler flue structure of claim 1, wherein an angle α formed between a horizontal projection plane of an inlet of the flue gas channel and a center line of the boiler is in a range of 0-45 °.

6. The dual-flue circulating fluidized bed boiler flue structure of claim 1, wherein each flue gas channel is provided with an independent heating surface of a coiled pipe, an expansion joint, a manhole door, a soot blower, a flue gas baffle, an air preheater and an induced draft fan from an inlet to an outlet.

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