CN201697115U

CN201697115U - Jet flow regulated and controlled biomass and coal circulating fluidized bed cofiring device

Info

Publication number: CN201697115U
Application number: CN2010202289649U
Authority: CN
Inventors: 张锴; 陈宏刚; 张凯华; 滕阳; 杨勇平
Original assignee: North China Electric Power University
Current assignee: North China Electric Power University
Priority date: 2010-06-09
Filing date: 2010-06-09
Publication date: 2011-01-05
Anticipated expiration: 2020-06-09

Abstract

A jet flow regulated and controlled biomass and coal circulating fluidized bed cofiring device consists of a circulating fluidized bed combustor, a cyclone separator 18, a dipleg 17 and a material returning device 15, wherein an upper bed body 9 and a lower bed body 6 of the fluidized bed are connected by an intermediate conical transitional section 8; the diameter of the upper bed body 9 is greater than the diameter of the lower bed body 6; the diameter ratio of the upper bed body 9 to the diameter of the lower bed body 6 is between 1.2 and 2.5; the top of the fluidized bed is connected with an inlet of the cyclone separator 18; a biomass tar cracker 10 is arranged in the lower bed body 6 of the fluidized bed body; an oxygen-rich air-carried biomass feeding pipe 2 is arranged on the lateral surface of the fluidized bed and is led to the center of the bed body and upwards extends to the lower part of the biomass tar cracker 10; an air chamber 12 is arranged at the bottom of the fluidized bed; a V-shaped gas distribution plate 4 is arranged in the air chamber; a clinker outlet 1 is arranged in the center of the bottom of the air chamber; a primary air inlet 3, a raw material coal inlet 5 and a secondary air inlet 7 are sequentially arranged on the lateral surface of the fluidized bed from bottom to top; the primary air inlet 3 is communicated with the V-shaped gas distribution plate 4; the secondary air inlet 7 is positioned between the lower bed body 6 of the fluidized bed and the conical transitional section 8; the top of the cyclone separator 18 is provided with a flue gas outlet 19; the bottom thereof is connected with the dipleg 17; the bottom of the dipleg 17 is connected with one side of the material returning device 15; the other side of the material returning device 15 is connected with the lower bed body 6 of the fluidized bed; and the material returning device 15 is provided with two-stage conveying inlets 14 and 16 and a loosening air inlet 13.

Description

The living beings and the coal recirculating fluidized bed cofiring device of jet regulation and control

Technical field

The utility model is a kind of solid-fuelled burner, relates in particular to a kind of living beings and coal recirculating fluidized bed cofiring device of jet regulation and control.

Background technology

Traditional fossil fuels such as living beings and coal and oil have very big compatibility, not only generating be easy to aspect heat supply utilizes and have energy industry now and be connected mutually, and be unique renewable resource that can directly be converted to carbon-containing fuel.International energy was deployed in the biomass energy report and pointed out in December, 2009, regenerative resource provides the primary energy in the whole world 13% at present, and biomass energy is in leading position in regenerative resource, be about 10%, wherein biomass energy accounts for 3% in country of the Organization of Economy and Cooperation Development, is mainly used in generating and heat supply; But in developing country, on average be about 22%, wherein some the country in addition up to more than 90%, based on domestic fuel.China's " medium-term and long-term development plan of regenerative resource " points out that China's biomass resource can be exchanged into the about 500,000,000 tons of standard coals of potentiality of the energy at present, and potentiality from now on can reach 1,000,000,000 tons of standard coals.The efficient utilization of biomass energy not only can reduce global greenhouse gases emission of carbon-dioxide, and helps alleviating the external interdependency of national petroleum resources, also provides opportunity for China leads the human fourth industrial revolution simultaneously.The high-tech development of therefore, carry out the living beings heat supply, generating electricity, producing clean fuel and aspects such as industrial chemicals and new material has extremely important strategic importance to the sustainable development of national economy.

In prior biological matter utilization of resources route, directly burning is the most simple and feasible a kind of technology of utilizing, at present both at home and abroad the direct combustion technology of living beings mainly comprise living beings separately burning and with two kinds of coal for mixing combustion.The independent burning of living beings is used for generating or cogeneration has obtained extensive use in North America and Europe, but mainly builds on large-scale farm or agriculture area of concentrating very much; China also develops dissimilar biomass fuel burning boilers, and technology is mature on the whole, mainly comprises firewood (wood chip) boiler, bagasse-fired boiler and chaff-fired boiler.Yet, compare with American-European countries, domestic biomass resource relatively disperses, supply as commodity is very limited, therefore, low capacity boiler during the domestic market is used and mostly to be, and owing to the restriction of reasons such as the seasonality of raw material and region radius, force the living beings enterprise of burning separately to be difficult to keep normal operation lacking under the support on policy prerequisite, have only timber mill and rice-hulling mill etc. to utilize the enterprise of abandoned biomass resource that its living space is just arranged.From technological layer, problems such as deposition, slagging scorification, corrosion are solved as yet well in the biomass combustion process, further study the influence behavior of the mobile heterogeneity of stove endoparticle to burning and heat transfer process for adopting fluid-bed combustion boiler also to need.

Although coal proportion in China's primary energy reduces year by year, total amount still presents the trend of rising, therefore carries out the mixed combustion technology of coal and living beings and has prior realistic meaning.The mixed combustion in boiler of living beings and coal, do not need existing coal combustion equipment is carried out too big change, promptly on the basis of existing coal-burning boiler, according to the living beings characteristics part transformation is carried out in fuel supply and combustion chamber, substituted the part fossil fuel with biomass fuel and carry out generating electricity or cogeneration after the mixed combustion.Especially the controllability of large power plant is big, can adapt to living beings mixed combustion in various degree, can mate living beings mixed combustion scale flexibly according to the obtaining degree of local biomass resource.Simultaneously, the living beings of high volatile and low sulfur content and the cooperative effect of coal for mixing combustion can reduce SOx and the NOx in the coal-burning boiler tail gas, and then effect is better to adopt the relatively low fluidization of ignition temperature.

Summary of the invention

The purpose of this utility model provide a kind of simple in structure, cost is low, easy-operating living beings and coal recirculating fluidized bed cofiring device.

The purpose of this utility model be achieved in that it by fluid bed, cyclone separator, dipleg, material returning device, biomass coke tar cracker, oxygen-enriched air carry living beings feed pipe, V-arrangement gas distribution grid, feed coal inlet, wind inlet, secondary wind inlet, a returning charge carry wind inlet, the loosening wind inlet of returning charge, lime-ash outlet and exhanst gas outlet to form.It is characterized in that: fluid bed top bed body is connected by the tapering transition section with the lower bed body, and top bed body diameter is greater than lower bed body diameter, and the area ratio is between 1.2 to 3.0; The fluid bed top is connected with cyclone inlet; Fluid bed lower bed body is built-in with the biomass coke tar cracker, and the side is provided with oxygen-enriched air and carries the living beings feed pipe and cause a body center and extend upwardly to biomass coke tar cracker below; The fluid bed bottom is provided with air compartment, and air compartment is built-in with the V-arrangement gas distribution grid, and the lime-ash outlet is established in the center of bottom; The fluid bed side is provided with wind inlet, feed coal inlet and secondary wind inlet from bottom to top successively one time, and one time wind enters the mouth and the connection of V-arrangement gas distribution grid, and secondary wind enters the mouth between fluid bed bottom and tapering transition section; The top of cyclone separator is an exhanst gas outlet, and the bottom is connected with dipleg, and the dipleg bottom is connected with material returning device one side, and the material returning device opposite side is connected with the fluid bed bottom; Material returning device is provided with two-stage and carries the wind inlet and become flexible the wind inlet.

It is further characterized in that: 1, living beings enter fluid bed and form pyrolysis rapidly behind the solid jet under the high speed oxygen-enriched air carries, the high-temp solid material that the gaseous state pyrolytic tar entrainments with high velocity air enters the biomass coke tar cracker, and biomass coke tar is cracked into micromolecular fuel gas after absorbing coal, semicoke or coke and oxygen combustion reaction liberated heat in cracker; 2, the general moisture height of biomass fuel, caloric value is low, is difficult for catching fire the introducing of center oxygen enrichment jet air and biomass coke tar cracker, remedy the not fire-hazardous defective of biomass fuel, biomass coke tar can be cracked into little molecule fuel gas rapidly simultaneously; 3, on biomass coke tar cracker top, part biological matter combustion gas component is reduced to nitrogen with formed part NOx in the combustion process, has reduced the discharging of combustion process oxynitrides; 4, material returning device is provided with loosening wind and two-stage conveying wind, can guarantee that the particle that cyclone separator separates returns the main body fluid bed smoothly; 5, the art of this patent can be transformed existing coal-fired fluidized bed boiler, when efficiently utilizing biomass resource, reduces the discharging of carbon dioxide, NOx and SOx.

The utility model compared with prior art has following unique advantage:

1. the utility model has adopted different feeding manners to living beings and coal, living beings deliver into fluid bed by the oxygen-enriched air strength, fast pyrogenation at high temperature after forming solid jet above the living beings jet feed pipe, and the pyrolysis bio-oil absorbs and further is cracked into micromolecular fuel gas after the heat of heat carrier is carried in high-speed jet secretly, simultaneously, solid product behind the biomass pyrolytic reaches the even mixing of different rerum natura particles in the bed by the interior circulation of particle under jet action, avoided living beings and coal to mix the reinforced defective that may cause two kinds of material layerings;

2. living beings jet feed pipe top is provided with the biomass coke tar cracker, can make biomass pyrolysis oil almost all be cracked into little molecule fuel gas in this cracker, has avoided big molecular biosciences matter tar that follow-up system is influenced;

3. the introducing of oxygen-enriched air living beings jet feed pipe and biomass coke tar cracker has remedied the not fire-hazardous defective of biomass fuel;

4. on biomass coke tar cracker top, the biological fuel gas of reproducibility is converted into nitrogen with formed part NOx in the coal-fired process, has restricted the discharging of oxynitrides effectively;

5. the top fluid bed that has an expanding reach can make granularity coal/biological particles less or that density is lighter turn back to fluid bed bottom emulsion zone;

In addition, the utility model also has the following advantage of general fluid bed:

1. the V-arrangement gas distribution grid is equipped with in the fluid bed bottom, guaranteed in fluid bed annular space district, to form bubbling fluidization, the mixing of particle and gas is more abundant, living beings and burning of coal reaction and heat transmission have effectively been promoted, improve the reaction efficiency of device, also helped the discharging of lime-ash simultaneously;

2. material returning device adopts the pressure balance that loosening wind and two-stage are carried the wind regulator control system, can guarantee that the particle that cyclone separator separates returns the main body fluid bed smoothly.

3. the utility model adds living beings in the circulating fluidized bed combustion coal boiler to, can reduce carbon dioxide, NOx and the SOx discharging of coal-burning boiler to some extent.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

As shown in the figure, the 1st, the lime-ash outlet, the 2nd, oxygen-enriched air and biomass feed inlet, 3 is wind inlets, the 4th, the V-arrangement gas distribution grid, the 5th, feed coal inlet, the 6th, fluid bed lower bed body, the 7th, secondary wind inlet, the 8th, fluid bed middle part changeover portion, the 9th, fluid bed top expanding reach, the 10th, biomass coke tar cracker, the 11st, oxygen-enriched air and living beings feed nozzle, the 12nd, air compartment, the 13rd, the loosening wind inlet of returning charge, the 14th, wind A inlet, the 15th, material returning device are carried in returning charge, the 16th, wind B inlet is carried in returning charge, the 17th, dipleg, the 18th, cyclone separator, the 19th, exhanst gas outlet.

The specific embodiment

Living beings are carried by the oxygen-enriched air strength and are entered fluid bed lower bed body 6 by living beings jet feed pipe 2, above living beings jet feed pipe 2, form solid jet, feed coal is then entered by feed coal inlet 5, and form countercurrent movement with living beings, under the disturbance of jet, realize mixing fully of living beings and coal, oxygen-enriched air through wind enter the mouth 3 and gas distributor 4 enter bed, make whole bed be in the stabilization fluid state.The burning exothermic reaction takes place in living beings and coal under the effect of oxygen-enriched air, living beings are heated and are generated bio-oil and further be cracked into little molecule fuel gas through biomass coke tar cracker 10, the gas that generates with coal combustion is carried a large amount of lime-ash and unburnt coal grain, semicoke etc. secretly and is moved up by fluid bed bottom 6 together.Secondary wind is entered by secondary wind inlet 7 strengthens burning, after in expanding reach 9, further burning, the part solid particle returns fluid bed bottom 6, remaining gas and dust enter cyclone separator 18 and carry out gas solid separation, high-temperature gas after the separation is discharged by the exhanst gas outlet 19 at cyclone separator 18 tops, solid enters dipleg 17, relies on dipleg 17 interior solid static pressures and carries the power of wind and loosening wind to return fluid bed bottom 6 smoothly from the two-stage of material returning device 15.Lime-ash is discharged by the lime-ash outlet 1 of fluid bed 6 bottoms.

Claims

1. the living beings and the coal recirculating fluidized bed cofiring device of jet regulation and control, by fluid bed, cyclone separator, dipleg, material returning device, biomass coke tar cracker, oxygen-enriched air carry living beings feed pipe, V-arrangement gas distribution grid, feed coal inlet, wind inlet, secondary wind inlet, a returning charge carry wind inlet, the loosening wind inlet of returning charge, lime-ash outlet and exhanst gas outlet to form, it is characterized in that: fluid bed top bed body (9) is connected by tapering transition section (8) with lower bed body (6), and top bed body (9) diameter is greater than lower bed body (6) diameter; The fluid bed top is connected with cyclone separator (18) inlet; Fluid bed lower bed body (6) is built-in with biomass coke tar cracker (10), and the side is provided with oxygen-enriched air and carries living beings feed pipe (2) and cause a body center and extend upwardly to biomass coke tar cracker (10) below; The fluid bed bottom is provided with air compartment (12), and air compartment is built-in with V-arrangement gas distribution grid (4), and lime-ash outlet (1) is established in the center of bottom; The fluid bed side is provided with a wind inlet (3), feed coal inlet (5) and secondary wind inlet (7) from bottom to top successively, a wind inlet (3) and V-arrangement gas distribution grid (4) are communicated with, and secondary wind inlet (7) is positioned between fluid bed bottom (6) and the tapering transition section (8); The top of cyclone separator (18) is exhanst gas outlet (19), and the bottom is connected with dipleg (17), and dipleg (17) bottom is connected with material returning device (15) one sides, and material returning device (15) opposite side is connected with fluid bed bottom (6); Material returning device (15) is provided with two-stage and carries wind inlet (14), (16) and loosening wind inlet (13).

2. living beings as claimed in claim 1 and coal recirculating fluidized bed cofiring device, it is characterized in that fluid bed bottom introducing living beings jet feed nozzle, both can make living beings pyrolysis rapidly in fluid bed bottom, also can enhanced biological matter and residual Jiao of burning evenly mix with coal.

3. living beings as claimed in claim 1 and coal recirculating fluidized bed cofiring device, it is characterized in that described fluid bed is built-in with the biomass coke tar cracker, can make biomass coke tar further be cracked into little molecule fuel gas, avoid the adverse effects such as obstruction of biomass coke tar follow-up pipeline.

4. living beings as claimed in claim 1 and coal recirculating fluidized bed cofiring device; it is characterized in that described fluid bed top has expanding reach; wherein the area ratio of expanding reach and fluid bed bottom is between 1.2 to 3.0; being provided with of expanding reach can make the part solid particle get back to fluid bed bottom emulsion zone and burn away, alleviate the separation burden of cyclone separator.