CN2527860Y

CN2527860Y - High, low mixed flow speed circulating fluidized bed boiler

Info

Publication number: CN2527860Y
Application number: CN 02223608
Authority: CN
Inventors: 何相助; 陈彩东
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-03-18
Filing date: 2002-03-18
Publication date: 2002-12-25
Anticipated expiration: 2012-03-18

Abstract

Disclosed is a recycle fluidized-bed boiler with mixed high flow velocity and low flow velocity. The utility model comprises a furnace wall, an integral furnace hearth, an air distribution plate, an air chamber, a drum, a super-heater, a coal economizer, a separator, an air pre-heater, a solid feed recycle device and a feed recycle pipe. The utility model is characterized in that the integral furnace is divided into three sections including a furnace hearth, a first burnout section and a second burnout section by a membrane wall. The three sections are naturally and organically formed into a high temperature U-shaped separator. The upper part of the furnace hearth is small and the lower part of the furnace hearth is big, and an immersed tube is arranged on the lower part of the furnace hearth. The utility model has novel concept, reasonable design and excellent technical performance.

Description

High and low mixture velocity CFBB

Technical field

The utility model relates to a kind of boiler plant, is specifically related to a kind of high and low mixture velocity CFBB.

Background technology

Its burner hearth height of existing high speed CFBB, sectional area are little, during work, raw coal is broken into the particle of 0-10mm particle size range, enter in the stove, pass through bellows, air distribution plate with the raw coal fluidized bed combustion with high-pressure blast, inner flue gas of the stove speed is greater than 5m/s, and a large amount of particles that high-temperature flue gas carries are sent into burner hearth again and repeatedly circulated and burn (ratio of internal circulating load and coal feeding amount claims circulating ratio) after separator separates.Dust concentration is even substantially in the whole stove, and the fine grained that separator is not caught after deduster is caught, is arranged to atmosphere by chimney again.This high speed CFBB has circulating ratio height, sufficient combustion, thermal efficiency height, flow velocity is fast, sectional area is little, furnace construction is compact, take up an area of less, the little igniting of air distribution plate area is easy to advantage, but because flow velocity height, furnace wall, heating surface, separator wearing and tearing are big.The flow velocity height, power consumption is big, and furnace cross-sectional area is little, but the furnace height height changes the high speed recirculating fluidized bed into to old stove, and drum, steelframe, boiler room all will be increased, and invest big, long in time limit.

And existing low speed CFBB, its structure is that burner hearth is low, sectional area is big.During work, raw coal is crushed to the 0-10mm size particles and enters in the stove, pass through bellows, air distribution plate with the coal fluidized bed combustion with high pressure positive blower, in 1.5 meters of air distribution plates, be furnished with pipe laying, the heat transfer coefficient of pipe laying is tens times of other heating surface, inner flue gas of the stove speed is less than 3m/5, high-temperature flue gas carries a spot of dust, after separating, separator sends into burner hearth again, circulating ratio is less, and dust concentration has obvious limit in stove, and generally about 1.5M is above to be dilute-phase zone, the particle that separator is not caught is arranged to atmosphere through chimney after deduster is caught again.This low speed CFBB, it is low to have the interior flow velocity of stove, and furnace wall, heating surface, separator wearing and tearing are lacked, and are furnished with the high pipe laying of heat transfer coefficient in the stove, load guarantees easily, and the complete wear consumption is few, and flow velocity is low, the corresponding attenuating of furnace height, change old boiler into the low speed recirculating fluidized bed, drum, steelframe, factory building are motionless, and framework is low, and flow velocity is low, plurality of advantages such as power consumption is low, but the thermal efficiency is low, and flow velocity is low, and sectional area is big, take up an area of big, to the boiler greater than 130T/H, pipe laying can't be arranged in the stove, and ignition difficulties.

Summary of the invention

Technical problem to be solved in the utility model is: overcome that existing high speed CFBB wearing and tearing are big, power consumption is many, burner hearth is high, old furnace modification is difficult, and the existing low speed CFBB thermal efficiency is low, sectional area is big, it is many to take up an area of, in the cauldron stove pipe laying can't arrange, the shortcoming of ignition difficulties, and a kind of good separating effect be provided, thoroughly solve that wearing and tearing, sufficient combustion, thermal efficiency height, investment are low, the high and low mixture velocity CFBB of duration weak point.

The technical solution adopted in the utility model is: this height, low mixture velocity CFBB has the furnace wall, whole burner hearth, air distribution plate, air compartment, drum, superheater, economizer, separator, air preheater, material-returning device, refeed line, inventive features of the present utility model is: with membrane wall whole burner hearth is divided into three sections: burner hearth, first burning segment, second burning segment, the lower furnace portion planar dimension is bigger, the upper furnace planar dimension is less, lower furnace portion is provided with pipe laying, burner hearth, first burning segment, three sections natural organic composition high temperature U type separators of second burning segment.

Combustion system of the present utility model and low speed are basic identical, difference is with membrane wall whole burner hearth to be divided into three sections, lower furnace portion is low speed bed, flow velocity is less than 4m/s, other two section flow velocitys are greater than 5m/s, a high temperature U of three sections natural organic compositions type separator, high-temperature flue gas separates by U type separator, to separate fine grained and send into lower furnace portion, the flue dust of not catching is arranged a separator again at boiler tail, send into burner hearth through feeding-back valve after the separation, flue gas is arranged to atmosphere by chimney behind deduster.The primary structure characteristics are that combustion system is divided into three sections: burner hearth, first burning segment, second burning segment.

A, lower furnace portion are provided with pipe laying;

B, lower furnace portion planar dimension are bigger, and flow velocity is lower than 4m/s;

C, upper furnace planar dimension are less, and flow velocity is greater than 5m/s;

D, the first burning segment planar dimension are less, and flow velocity is greater than 5m/s;

E, the second burning segment planar dimension are less, and flue gas is up;

Form the U type between f, first burning segment, second burning segment and separate loop back configuration;

After g, the high group economizer, install and separate send-back system, form secondary and separate loopback;

H, burner hearth and first burning segment, second burning segment organically combine, and form the U type and separate send-back system.

The utility model major advantage effect: emulsion zone is low speed bed, and wearing and tearing are few, though dilute-phase zone flow velocity height, dust concentration is low, and particle is little, and it is little to wear and tear, and the utility model has thoroughly solved the technical barrier of boiler abrasion;

Because top be bed at a high speed, carrying capacity is strong, the separative efficiency height, and flue gas is by three sections burnings in addition, and flue gas flow is long, and the particle time of staying is long, sufficient combustion, thermal efficiency height (than the height of going back at a high speed bed), the thermal efficiency 〉=85%, unburned carbon in flue dust≤7%;

Because the rear portion is furnished with the high pipe laying of coefficient of heat perception, load can guarantee that wearing and tearing are lacked, invest low, the duration weak point;

High and low mixture velocity CFBB had both had the advantage of high speed bed boiler and low speed bed boiler, had overcome the shortcoming of high speed bed boiler and low speed bed boiler again, and overall target is better than the new and effective CFBB of other type.

Description of drawings

Fig. 1 is the utility model structural representation.

Fig. 2 is a superheater example structure schematic diagram.

Fig. 3 is an economizer example structure schematic diagram.

Fig. 4 is a separator example structure schematic diagram.

Fig. 5 is an air preheater example structure schematic diagram.

The specific embodiment

Referring to Fig. 1, the utlity model has furnace wall 1, whole burner hearth 2, air distribution plate 3, air compartment 4, drum 5, superheater 6, high group economizer 7, separator 8, low group economizer 9, air preheater 10, material-returning device 11, refeed line 12, inventive features of the present utility model is: with membrane wall 13 whole burner hearth is divided into three sections: burner hearth 14, first burning segment 15, second burning segment 16, burner hearth 14 lower flat sizes are bigger, burner hearth 14 upper plane sizes are less, burner hearth 14 bottoms are provided with pipe laying 17, burner hearth 14, first burning segment 15,16 3 sections natural organic composition high temperature U type separators of second burning segment.

Pipe laying of the present utility model, air distribution plate, air compartment, furnace wall, drum, superheater, separator, economizer, air preheater, material-returning device, these parts of refeed line are prior art, as pipe laying, for many water pipes are arranged formation, its operation principle is that the water in the drum enters the pipe laying heating, return drum again after becoming water liquid two-phase, in drum, carry out vapor-liquid separation, after steam enters superheater and heats, offer the user, the water in the drum enters the pipe laying circulation once more.And for example superheater can adopt the coiled pipe structure, and its effect is after the steam that drum is exported is heated again, to deliver to the user; Separator is generally multi-cyclone tube isolating construction, has whirlwind tube 18, whirlwind 19, smoke pipe 20, ash hole 21, and its effect is with the ash in the flue gas.Gas separates; Economizer is generally cast iron pipe comb or steel coiled pipe structure, and its operation principle is with behind the running water feed-water preheating, enters boiler-steam dome; Air preheater is generally calandria structure, and its operation principle is after room air is entered the comb preheating, to enter air compartment, the boiler of feeding burning.The specific embodiment of these boiler components sees also Fig. 2. Fig. 3. and Fig. 4. Fig. 5.

The platy structure that the membrane wall that adopts in the present utility model feature can adopt water pipe and steel disc weldering system to form.

Claims

1, a kind of high and low mixture velocity CFBB, have furnace wall, whole burner hearth, air distribution plate, air compartment, drum, superheater, economizer, separator, air preheater, material-returning device, refeed line, it is characterized in that with membrane wall whole burner hearth being divided into three sections: burner hearth, first burning segment, second burning segment, lower furnace portion planar dimension are bigger, the upper furnace planar dimension is less, lower furnace portion is provided with pipe laying, burner hearth, first burning segment, three sections natural organic composition high temperature U type separators of second burning segment.