CN206145668U - Efficiency of circulating fluidized bed boiler combustion is improved device - Google Patents

Abstract

The utility model provides an efficiency of circulating fluidized bed boiler combustion is improved device, includes cyclone, cyclone is including a gas -solid mixture access road of treating the separation and the flue gas exhaust center section of thick bamboo including the combustible substance that supplies the after -separating, a center section of thick bamboo is connected with an exhaust pass, wherein, be in last being provided with of exhaust pass supplies to supply the after burning wind spout that the burning let in with wind. The utility model discloses can improve the combustion efficiency of circulating fluidized bed boiler.

Description

Improve the device of burning in circulating fluid bed boiler efficiency

Technical field

This utility model is related to a kind of device of CFBB, especially a kind of to improve CFBB combustion Burn the device of efficiency.

Background technology

For a long time based on coal, the burning of coal brings substantial amounts of pollutant emission to China's energy resource structure, improves coal combustion Burning efficiency reduces the problem that pollutant emission is that industrial quarters is devoted to solving simultaneously.Nitrogen oxides (NOx) are that coal-burning boiler is produced Main atmospheric pollution one of pollutant, excessive nitrogen oxides cause serious ecological environment problem.Therefore, control fire The discharged nitrous oxides of coal-fired boiler in power plant are most important.In national environmental protection regulation, it is desirable to which boiler has to carry out 100mg/Nm³ Discharge standard, the original discharged nitrous oxides concentration of current CFBB can not be directly up to standard.Therefore it is ciculation fluidized Bed boiler is faced with the problem that must further reduce discharged nitrous oxides.

At present in existing technology, the technology of CFBB control NOx emission can be divided into two classes：One is by each Plant the NOx generation amount that technological means are reduced in combustion process, i.e. low NOx combusting technology；Two is that the NOx to generate is passed through technology Means are removed from flue gas, i.e. gas denitrifying technology.Gas denitrifying technology complex process, investment and operating cost height, undoubtedly drop The low market competitiveness of CFBB.Traditional low NOx combusting technology mainly includes low oxygen combustion, adopts in burner hearth With Researched of Air Staging Combustion Burning Pulverized Coal, fuel-staged combustion, flue gas recirculation etc..

Chinese patent application 201310723729.7 proposes a kind of combustion of CFBB low-nitrogen oxide discharging Firing method, by the Researched of Air Staging Combustion Burning Pulverized Coal in burner hearth and widens the distance between three layers of secondary wind to reduce discharged nitrous oxides, But too high secondary wind can affect goods fluid in stove, reduce circulating load, shortens the time of staying of the fuel in burner hearth, unfavorable In the abundant burning of fuel, boiler combustion efficiency is affected.Chinese patent application 201310592710.3 proposes a kind of reduction and follows The device and method of the nitrogen oxides in circulation fluidized bed boiler flue gas product, the First air and secondary wind to CFBB Smoke backflow technology is adopted simultaneously, is reduced the oxygen concentration of fire area, and then is suppressed the production of nitrogen oxides；But this mode Flue gas flow rate in recirculating fluidized bed is improve, the abrasion of stove internal heating surface can be aggravated, while the reduction of oxygen concentration is also resulted in Emulsion zone combustion share is reduced, ash content carbon is raised, and affects boiler combustion efficiency.Although these technologies are for control recycle stream Fluidized bed boiler discharged nitrous oxides are played a significant role, but reduce the efficiency of combustion of CFBB, to boiler Operation have a negative impact.How the burning effect of boiler is improved while CFBB discharged nitrous oxides are controlled Rate, is the major issue for being badly in need of solving in industry.

Utility model content

The purpose of this utility model is for above-mentioned deficiency, there is provided a kind of dress of raising burning in circulating fluid bed boiler efficiency Put.

Realize that the technical scheme of this utility model purpose is to provide a kind of dress for improving burning in circulating fluid bed boiler efficiency Put, including cyclone separator, the cyclone separator includes gas-solid mixture access road to be separated and for the cigarette after separation The central tube that gas is discharged, the central tube are connected with an exhaust pass；Wherein, it is provided with for supplementing combustion on the exhaust pass The afterburning wind snout that burning wind is passed through.

According to a specific embodiment, the exhaust pass includes the cylindrical structure being directly connected to center letter, Yi Jiyu The group section of cylindrical structure connection, away from being disposed with afterburning wind snout on the lunette of group section on the cylindrical structure.

According to a specific embodiment, on the lunette, a line afterburning air port is disposed with vertical direction.

According to a specific embodiment, the number in the afterburning air port is 4-12, is uniformly distributed in a line on lunette.

According to a specific embodiment, on the lunette, multirow afterburning wind snout is disposed with vertical direction.

According to a specific embodiment, the afterburning air port of every a line of multirow afterburning wind snout angle phase to each other Together.

According to a specific embodiment, two row afterburning wind snouts on the lunette, are disposed with, wherein, the first row has N1 Afterburning wind snout, between afterburning wind snout, angle is identical, is distributed in the both sides of exhaust pass semicircle wall, and N1 is natural number； Second row has N2 afterburning wind snout, is arranged on the offside direction of the access road, and the first row that is arranged in straggly is mended Between combustion wind snout, N2 is natural number.

According to a specific embodiment, also include the back-end ductwork with the exhaust pass end UNICOM.

According to a specific embodiment, described device also includes CFBB, with the gas-solid mixture entrance Passage UNICOM.

According to a specific embodiment, also including air collecting box, itself and the afterburning wind snout UNICOM.

By above-mentioned technical proposal, it is known that the beneficial effects of the present invention is：

(1) the afterburning mouth by arranging on exhaust pass is passed through aftercombustion wind so that contain in stove chamber inner combustion flue gas Some carbon monoxides and flying dust combustible component are sufficiently mixed, are burnt completely with afterburning gas；

(2) solve to reduce the boiler combustion efficiency reduction that NOx technologies are brought due to Researched of Air Staging Combustion Burning Pulverized Coal by this device Problem.

Description of the drawings

Schematic devices of the Fig. 1 for the raising burning in circulating fluid bed boiler efficiency of this utility model embodiment；

Fig. 2A and 2B is respectively the first embodiment top view and front view of afterburning wind snout.

Fig. 3 A and 3B are respectively second embodiment top view and front view of afterburning wind snout.

Specific embodiment

To make the purpose of this utility model, technical scheme and advantage become more apparent, below in conjunction with specific embodiment, and Referring to the drawings, the utility model is described in further detail.

Shown in Figure 1, this utility model embodiment provides a kind of device for improving burning in circulating fluid bed boiler efficiency, Including cyclone separator 2：

The cyclone separator 2 includes gas-solid mixture access road to be separated and for the nitrogen-containing oxide after separation The central tube 4 that flue gas is discharged, the central tube 4 connect an exhaust pass 5 and connect；

Wherein, the afterburning wind snout 7 being passed through for aftercombustion wind is provided with the exhaust pass 5.

In Fig. 1 shown devices, a kind of specific connected mode can be：Cyclone separator 2, with recirculating fluidized bed burner hearth 1 outlet is communicated, material returning device 3, respectively with the solid outlet and recirculating fluidized bed burner hearth 1 of cyclone separator 2 on returning charge mouth phase It is logical；Central tube 4, is arranged in the top location roughly halfway up of cyclone separator 2；Exhaust pass 5 is connected with central tube 4；With And back-end ductwork 6, communicate with exhaust pass 5, in back-end ductwork, include back-end surfaces.The exhaust pass 5 being connected with central tube 4 Position is provided with afterburning wind snout 7, and Fig. 2 and Fig. 3 is the embodiment that two class afterburning mouths are arranged, afterburning wind snout 7 and external channel It is connected, afterburning wind is passed through in exhaust pass 5.

Wherein, one end is directly connected to central tube 4 in exhaust pass 5, the section is referred to as cylindrical structure, and exhaust pass 5 is also Including the group section being connected with the cylindrical structure, (to make cylindrical structure be connected with group section and connect, a part for cylinder can Can be cut open, formed irregular roundness barrel structure), on the cylindrical structure away from be disposed with the lunette of group section afterburning wind spray Mouth 7.

For the setting form of afterburning wind snout 7 in this utility model embodiment, there can be various ways, can be vertical Arrange in a line on direction, or arrange in multirow.

When arranging using a line, afterburning wind snout 7 is preferably made to be uniformly distributed along lunette, the quantity of distribution can be with For 1 or multiple, preferably 2-20 is further preferred for 4-12, it is further preferred that 6.It is full in device Under load condition, the afterburning being passed through at this position is enough as high velocity smoke is moved with wind energy, is fully blended with flue gas, by cigarette Combustible component in gas burns completely.At low load, while impartial reduce the supplementary fuel wind that all afterburning mouths are passed through, It is up to identical effect.

When being arranged using multirow, the afterburning wind snout of every a line of preferred multirow afterburning wind snout is along semi-circular structure It is uniformly distributed.It is also preferred that the afterburning wind snout per a line is staggered in vertical direction.

A kind of specific two rows arrangement can be：The first row has N1 afterburning mouth, and between afterburning mouth, angle is identical, point The both sides of exhaust pass semicircle wall are distributed in, N1 is natural number；Second row has N2 afterburning mouth, angle and the first row afterburning mouth Angle is identical, is arranged on the offside direction of the access road, and it is straggly be arranged between the first row afterburning wind snout, N2 For natural number.

Optionally, air collecting box can also be included in device, which is connected to the afterburning air port.

It is listed below the specific embodiment of two kinds of afterburning wind snouts：

Afterburning wind snout the first embodiment

Fig. 2A and 2B is respectively the top view and main view for implementing afterburning wind snout of the present utility model the first embodiment Figure, is disposed with multiple afterburning mouths, is evenly arranged on the semicircle wall of exhaust pass 5, in 180 ° points on figure middle outlet flue 5 Cloth.All afterburning mouths are in exhaust pass bottommost, and angle is identical between each.Afterburning mouth can be 4～12 afterburning mouths. Under full load situation, the afterburning being passed through at this position is fully blended with flue gas as high velocity smoke is moved with wind energy is enough, Combustible component in flue gas is burnt completely.At low load, while impartial reduce the supplementary fuel use that all afterburning mouths are passed through Wind, is also up to identical effect.

Second embodiment specific embodiment of afterburning wind snout

Fig. 3 A and 3B are respectively the top view and main view for implementing afterburning wind snout of the present utility model the first embodiment Figure, has two rows on figure middle outlet flue 5, be distributed multiple afterburning mouths, be arranged on the semicircle wall of exhaust pass 5, the first row There is N1 afterburning mouth, on exhaust pass wall at 1/4 position of bottom, angle is identical between each afterburning mouth, is distributed in The both sides of 5 semicircle wall of exhaust pass.Second row has N2 afterburning mouth, and angle is identical with the first row afterburning mouth angle, is located at The bottom of exhaust pass 5, is arranged on the offside direction of the access road that (referring to described in Fig. 3 A, access road hangs down in being located at On the left of line, then the second row afterburning mouth be located at perpendicular bisector on the right side of), it is straggly to be arranged on the right of the first row between three afterburning mouths, N1 and N2 is natural number.The afterburning mouth of this kind of mode can have multirow to arrange, afterburning mouth number can also change to multiple (＞ 6 It is individual), and bottom line afterburning mouth position will be with the Way in (gas-solid mixing i.e. to be separated of cyclone separator 2 Thing access road) it is contrary.Under full load situation, the afterburning being passed through at this position is enough as high velocity smoke is moved with wind energy, with Flue gas is fully blended, and the combustible component in flue gas is burnt completely.In the case of underload, institute is reduced by simultaneously impartial There are supplementary fuel wind or close certain several afterburning mouth that afterburning mouth is passed through, it is also possible to reach the effect of abundant burn combustible thing Really.

The above embodiments are equally applicable on the CFBB with multiple cyclone separator.

Solve to reduce the boiler combustion that NOx technologies are brought due to air separation burning using the device of this utility model embodiment Burn the problem that efficiency is reduced：

During this utility model is realized, fuel (such as coal) and height are passed through respectively into recirculating fluidized bed burner hearth 1 In theoretical combustion air but less than the burning wind of conventional combustion air capacity, keep the atmosphere in recirculating fluidized bed burner hearth 1 In reducing atmosphere, generation includes the gas-solid mixing of the flue gas with a small amount of carbon monoxide and the particulate matter with a small amount of coke Thing；The gas-solid mixture that recirculating fluidized bed burner hearth 1 is produced is made to enter cyclone separator 2, the most of granule in gas-solid mixture Separated, the returning charge mouth on Jing material returning devices 3 and recirculating fluidized bed burner hearth 1 sends recirculating fluidized bed burner hearth 1 again back to, flue gas entrainment is few Amount fine grained enters central tube 4；Supplementary fuel wind is passed through into exhaust pass 5 by afterburning mouth 7, the oxidation in flue gas is made Carbon and coke combustible component burn completely.

In this utility model, as the amount of the burning wind being input in burner hearth is slightly above theoretical combustion air but less than normal Rule combustion air amount so can both make to be maintained in CFBB 1 to cause excess air coefficient to be 1.05-1.08 Reducing atmosphere, completes burning in the burner hearth that in turn ensure that most of combustible component, remaining combustible component is less, in exhaust pass After-flame by interior.

The amount of the aftercombustion wind being passed through into exhaust pass 5 by combustion-compensating device 7 accounts for burner total air 10%-15%, the air quantity are passed through in exhaust pass, are as far as possible fully blended with flue gas so that in flue gas it is contained it is flammable into Divide and fully burn, so as to ensure boiler combustion efficiency.

Particular embodiments described above, has carried out entering one to the purpose of this utility model, technical scheme and beneficial effect Step is described in detail, it should be understood that be the foregoing is only specific embodiment of the utility model, is not limited to this reality With new, all within spirit of the present utility model and principle, any modification, equivalent substitution and improvements done etc. all should be included Within protection domain of the present utility model.

Claims (10)

1. a kind of device for improving burning in circulating fluid bed boiler efficiency, including cyclone separator, it is characterised in that：

The central tube that the cyclone separator includes gas-solid mixture access road to be separated and discharges for the flue gas after separation, The central tube is connected with an exhaust pass；

Wherein, the afterburning wind snout being passed through for aftercombustion wind is provided with the exhaust pass.

2. device according to claim 1, it is characterised in that the exhaust pass includes the circle being directly connected to center letter Barrel structure, and the group section being connected with the cylindrical structure, are arranged away from the lunette of group section on the cylindrical structure There is afterburning wind snout.

3. device according to claim 2, it is characterised in that be disposed with a line benefit in vertical direction on the semicircle barrel Combustion air port.

4. device according to claim 3, it is characterised in that the number in the afterburning air port is 4-12, on lunette It is uniformly distributed in a line.

5. device according to claim 2, it is characterised in that be disposed with multirow afterburning in vertical direction on the lunette Wind snout.

6. device according to claim 5, it is characterised in that the afterburning air port of every a line of the multirow afterburning wind snout Angle is identical to each other.

7. device according to claim 5, it is characterised in that two row afterburning wind snouts are disposed with the lunette, its In,

The first row has N1 afterburning wind snout, and between afterburning wind snout, angle is identical, is distributed in exhaust pass semicircle wall Both sides, N1 are natural number；

Second row has N2 afterburning wind snout, is arranged on the offside direction of the access road, and straggly is arranged in first Between row afterburning wind snout, N2 is natural number.

8. device according to claim 1, it is characterised in that also include the afterbody cigarette with the exhaust pass end UNICOM Road.

9. device according to claim 1, it is characterised in that described device also includes CFBB, it is and described Gas-solid mixture access road UNICOM.

10. device according to claim 1, it is characterised in that also including air collecting box, which is joined with the afterburning wind snout It is logical.