CN204962735U

CN204962735U - Two furnace circulating fluidized bed boilers

Info

Publication number: CN204962735U
Application number: CN201520714982.0U
Authority: CN
Inventors: 吕俊复; 张缦; 黄晓丹; 杨海瑞; 岳光溪
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2015-09-15
Filing date: 2015-09-15
Publication date: 2016-01-13
Anticipated expiration: 2025-09-15

Abstract

The utility model provides a two furnace circulating fluidized bed boilers, it includes two furnace of two complete independences, two furnace of set up side by side, and leave the clearance between the two. Every furnace below has independent air distribute device and plenum, arrange the cyclone that a set of structure is the same respectively in opposed outside separately at two furnace looks proximal surfaces, two furnace, two sets of separator and sharing connection flues are all about the vertical central plane symmetrical arrangement of circulating fluidized bed boiler, two sets of cyclone connect the flue through the sharing respectively and are connected with same afterbody convection gas pass. The utility model discloses a furnace water -cooling wall is the single face and is heated, avoids the heating load difference between the parallelly connected tube panel and presses the undulant tilting table phenomenon that causes because of the bed, and further improvement operation in -process control system's the reliability and the flexibility of regulation reduce boiler station service power consumption rate, the advantage is provided for arranging of the overcritical circulating fluidized bed boiler temperature heating surface of double reheat, furnace design simultaneously is simple, is convenient for maximize.

Description

A kind of twin furnace CFBB

Technical field

The utility model relates to overcritical large circulating fluidized bed boiler, and particularly double reheat supercritical circulating fluidized bed boiler, belongs to technical field of combustion equipment.

Background technology

Along with CFBB constantly maximizes, burner hearth yardstick progressively increases, water-cooling wall be arranged as key problem, because burner hearth circumferential length is smaller, arrange that abundant water-cooling wall is except improving furnace height, can only adopt the two-sided water-cooling wall be heated.From the angle of burning, furnace height is more than just little to the improvement of efficiency of combustion after 45m; Afterbody more than 35m, therefore should make furnace height within 45m to the requirement for height furnace height of flow through shaft as far as possible.The two-sided water-cooling wall be heated is adopted to be alleviate the effective measures that contradiction arranged by water-cooling wall, this is feasible under Natural Circulation condition, but at supercritical conditions, consider the thermic load difference between tube panel in parallel, should avoid adopting the two-sided water-cooling wall that is heated as far as possible.

In addition, due to the increase of furnace profile, penetrating of Secondary Air is made to become very difficult, therefore, in engineer applied, occurred the two air distributor structure burner hearth of pants leg type, this chamber structure is the Split type structure that bottom adopts two air distribution plate, and a burner hearth is merged in the middle and upper part of burner hearth, easily there is both sides bed pressure fluctuation in boiler running process, then need to rely on First air air pressure air flow to regulate.Therefore split chamber structure is in operation very high with adjustment sensitivity requirement to the reliability of control system, and owing to increasing the reasons such as controllable register, First air fan pressure head is higher.Meanwhile, the two air distribution plate chamber structure of pants leg type is very complicated, and design, manufacture, installation and operation expense are higher.

Special in double reheat boiler, the requirement meeting rationalization's burning should be considered during chamber design, also to ensure that the outlet steam temperature of main steam and double reheating steam reaches rated value, therefore the layout of three groups of high-temperature surfaces becomes very difficult, under CFBB low-temperature burning condition, if do not adopt external heat exchanger, then this problem becomes more outstanding, if employing external heat exchanger, station service power consumption rate then can be brought high, operation maintenance workload is large and increase extra urgent makeup Water System etc., impact is brought to the economy of boiler and reliability.

Utility model content

The purpose of this utility model is to provide a kind of large-scale twin furnace CFBB with multiple separator, for the layout of double reheat supercritical circulating fluidized bed boiler high-temperature surface improves favourable condition, make furnace wall cooling be one side to be heated, thus the tilting table phenomenon avoiding the thermic load difference between tube panel in parallel and the fluctuation of both sides bed pressure to cause, improve the reliability of control system and the flexibility of adjustment in running further.Make primary air fan pressure head reduce simultaneously, and then reduce station service power consumption rate.

The technical solution of the utility model is as follows: a kind of twin furnace CFBB, is characterized in that: it comprises two completely independently the first burner hearth, the second burner hearth, two groups of cyclone separators and afterbody convection pass; First burner hearth and the second burner hearth are set up in parallel, and leave gap between two burner hearths, have independently air-distribution device and air compartment below each burner hearth; The identical cyclone separator of one group of structure is arranged in parallel respectively in the outside on two burner hearth adjacent surfaces opposite separately, often organize cyclone separator and at least comprise two cyclone separators, each cyclone separator has a gas approach communicated with burner hearth and an exhaust pass, and the exhaust pass of each cyclone separator shares connection flue by homonymy and communicates with afterbody convection pass; Described two burner hearths, two groups of cyclone separators and the shared flue that connects all are arranged symmetrically with about the vertical median plane of described CFBB.

Preferably, between the first burner hearth and the second burner hearth, level connection joint flue is set.

Preferably, the first described burner hearth and the second burner hearth are formed by fin panel casing; The cross sectional shape of described first burner hearth and the second burner hearth, size and furnace height are all identical.

The utility model compared with prior art, have the following advantages and the technique effect of high-lighting: adopt two independently burner hearths, are furnished with independent air distribution plate and bellows respectively, make furnace wall cooling be one side to be heated, avoid thermic load difference between tube panel in parallel and to fluctuate the tilting table phenomenon caused because of bed pressure, further increasing the reliability of control system and the flexibility of adjustment in running; Simultaneously owing to cancelling the controllable register of the two air distribution plate burner hearth pressure at both sides of balance pants leg type, primary air fan pressure head is reduced, thus reduces station service power consumption rate; In addition, the layout being set to double reheat supercritical circulating fluidized bed boiler high-temperature surface of two burner hearths provides advantage; This technical scheme has chamber design simply simultaneously, is convenient to the advantages such as maximization.

Accompanying drawing explanation

A kind of two completely independently overall structure schematic diagrames (front view) of twin furnace CFBB of being set up in parallel of burner hearth that Fig. 1 provides for the utility model.

Fig. 2 be two completely independently burner hearth be set up in parallel, between two burner hearths, local arranges the overall structure schematic diagram (front view) of the twin furnace CFBB of level connection joint flue.

Fig. 3 is the overall structure schematic diagram (top view) of the twin furnace CFBB with six identical cyclone separators.

Fig. 4 is the overall structure schematic diagram (top view) of the twin furnace CFBB with eight identical cyclone separators.

Fig. 5 be there are six identical cyclone separators two burner hearths between local the overall structure schematic diagram (top view) of the twin furnace CFBB of level connection joint flue is set, illustrated therein is fluid in cyclone separator and the type of flow between separator outlet flue and afterbody convection pass.

In figure: 1-first burner hearth; 2-second burner hearth; 3-water-cooling wall; 4-air-distribution device; 5-air compartment; 6-level connection joint flue; 7-separator outlet flue; 8-separator inlet flue; 21-first shares and connects flue; 22-second shares and connects flue; 23-afterbody convection pass; 24-first group of separator; 25-second component is from device.

Detailed description of the invention

Below by embodiment, and by reference to the accompanying drawings, the technical solution of the utility model is described in further detail.

The critical piece of CFBB generally comprises burner hearth, cyclone separator, material returning valve and afterbody convection pass, also can comprise external heat exchanger etc.; Superheater, reheater and economizer surface is furnished with in afterbody convection pass.

As shown in Figure 1, it contains two completely independently the first burner hearth 1, second burner hearth 2, two groups of cyclone separators and afterbody convection pass 23 to a kind of twin furnace CFBB that the utility model provides; First burner hearth and the second burner hearth are set up in parallel, and leave certain interval between two burner hearths, have independently air-distribution device 4 and air compartment 5 below each burner hearth; The cross sectional shape of two burner hearths described in the utility model, size and furnace height are all identical, and two burner hearths are formed by fin panel casing 3.The identical cyclone separator of one group of structure is arranged in parallel respectively in the outside on two burner hearth adjacent surfaces opposite separately, often organize cyclone separator and at least comprise two cyclone separators, each cyclone separator has a gas approach communicated with burner hearth 8 and an exhaust pass 7, and the exhaust pass of each cyclone separator shares connection flue by homonymy and communicates with afterbody convection pass; So-called one group of identical cyclone separator, refer to often organize cyclone separator quantity and all equal but layout of gas approach of physical dimension can may be different according to the general layout of boiler; Described two burner hearths, two groups of cyclone separators and the shared flue that connects all are arranged symmetrically with about the vertical median plane M of described CFBB.

In order to better balance the air pressure of two burner hearths, between two burner hearths, level connection joint flue 6 (see Fig. 2) can also be set local location.

Fig. 3 and Fig. 4 is the structural representation of two embodiments of the present utility model, wherein, the arrangement with six mutually isostructural cyclone separators is given in Fig. 3, six cyclone separators divide into two groups, i.e. first group of cyclone separator 24 and second group of cyclone separator 25, these two groups of cyclone separators are arranged symmetrically in the outside on two burner hearth adjacent surfaces opposite separately respectively.Give the arrangement with eight mutually isostructural cyclone separators in Fig. 4, eight cyclone separators divide into two groups, are arranged symmetrically in the outside on two burner hearth adjacent surfaces opposite separately respectively.

The course of work of the present utility model is as follows:

As shown in Figure 5, ash-laden gas enters each cyclone separator by the gas approach of each cyclone separator, after separator centrifugation, gas containing solid granule enters shared connection flue through respective exhaust pass, both sides flue gas connects after flue converges in each side, shares connect flue 21 and second and share and be connected flue 22 and enter same afterbody convection pass 23 respectively by first.

Claims

1. a twin furnace CFBB, is characterized in that: it comprises two completely independently the first burner hearth (1), the second burner hearth (2), two groups of cyclone separators and afterbody convection pass (23); First burner hearth and the second burner hearth are set up in parallel, and leave gap between two burner hearths, have independently air-distribution device (4) and air compartment (5) below each burner hearth; The identical cyclone separator of one group of structure is arranged in parallel respectively in the outside on two burner hearth adjacent surfaces opposite separately, often organize cyclone separator and at least comprise two cyclone separators, each cyclone separator has a gas approach communicated with burner hearth (8) and an exhaust pass (7), and the exhaust pass of each cyclone separator shares connection flue by homonymy and communicates with afterbody convection pass; Described two burner hearths, two groups of cyclone separators and the shared flue that connects all are arranged symmetrically with about the vertical median plane of described CFBB.

2. a kind of twin furnace CFBB according to claim 1, is characterized in that: arrange level connection joint flue (6) between the first burner hearth and the second burner hearth.

3. a kind of twin furnace CFBB according to claim 1 and 2, is characterized in that: described the first burner hearth (1) and the second burner hearth (2) are formed by fin panel casing.

4. a kind of twin furnace CFBB according to claim 1 and 2, is characterized in that: the cross sectional shape of described first burner hearth (1) and the second burner hearth (2), size and furnace height are all identical.