CN202204155U - Organic thermal medium boiler of environmental-friendly energy-saving recirculating fluidized bed - Google Patents

Abstract

The utility model discloses an environment-friendly and energy-saving circulating fluidized bed organic heat carrier boiler, which comprises a furnace and a vertical flue at the tail. The furnace and the vertical flue are respectively provided with a thermal insulation refractory material layer and a steel frame, and the top is provided with a ceiling. One end of the ceiling pipe is connected with the outlet header; the upper part of the inner wall of the furnace is provided with a square plate radiation heating tube bundle, the lower part is provided with a coal supply port connected with the coal hopper, and the bottom is provided with an equal pressure air box, an air distribution plate and a wind cap; A multi-tube cyclone separation device connected with the upper flue of the furnace is arranged between the vertical flue at the tail and the upper part of the furnace. The lower part is connected to the material return port; the vertical flue is provided with segmented high and low temperature convection tube bundles, and the bottom is provided with an air preheater connected with the equal pressure air box, and the air preheater is provided with a flue gas outlet. It solves the technical problems of poor heat transfer effect, multiple faults, difficult maintenance and easy blockage of the material return port in the prior art.

Description

Environmental protection and energy saving circulating fluidized bed organic heat carrier boiler

Technical Field The utility model belongs to the technical field of organic heat carrier boilers, and relates to an environmentally friendly and energy-saving circulating fluidized bed organic heat carrier boiler.

Background Art Most of the circulating fluidized bed organic heat carrier boilers in the prior art are assembled as a whole, the convection tube bundle is bulky, and there are a lot of convection tubes inside. Boilers with this structure have technical problems such as poor assembly flexibility, difficulty in maintenance and replacement of components, bias flow phenomenon in the organic heat carrier inlet header, and low flow rate parts of the convection tube are easily burned by high-temperature flue gas. The circulating fluidized bed organic heat carrier boilers in the prior art mainly have the following defects: 1. Due to the overall design of the convection heating surface, the flow velocity of the organic heat carrier in the pipeline in the high temperature area and the flue gas in the tube bundle in the low temperature area is too low , which reduces the heat absorption effect. If the high temperature or low temperature section is seriously damaged, all the convective heating surfaces need to be replaced, which makes the maintenance cost very high; 2. The cyclone separation device is located in the organic heat carrier furnace. When there is a problem, the organic heat carrier furnace has been damaged and must be shut down for maintenance. 3. The temperature of the furnace is not easy to adjust. When the temperature of the furnace is too high, it is easy to coke, which affects the heat transfer effect, reduces the thermal efficiency of the organic heat carrier furnace, and the feeding port is easily blocked. The unreasonable internal structure of the existing circulating fluidized bed organic heat carrier furnace affects the heat transfer effect, the thermal efficiency decreases during long-term operation, and it is difficult to repair when the interior is damaged. The operating cost of the bed organic heat carrier furnace increases.

SUMMARY OF THE INVENTION The purpose of this utility model is to solve the problem of poor heat transfer effect caused by unreasonable internal structure of the existing circulating fluidized bed organic heat carrier furnace, low thermal efficiency during long-term operation, difficult maintenance when internal damage occurs, high damage frequency, and trouble-free operation The technical problems of short time and easy blockage of the material return port can reduce the maintenance and operation costs of the existing circulating fluidized bed organic heat carrier furnace. Provide a high-efficiency, energy-saving and environment-friendly circulating fluidized bed organic heat carrier furnace,

In order to achieve the above purpose, the utility model environmental protection and energy-saving circulating fluidized bed organic heat carrier boiler includes a furnace and a vertical flue at the tail, and the furnace and the vertical flue at the tail are respectively provided with a thermal insulation refractory layer and a steel frame; The top of the furnace and the vertical flue at the tail are provided with a ceiling pipe, and one end of the ceiling pipe communicates with the outlet header; the upper part of the inner wall of the furnace is provided with a square plate radiation heating tube bundle; A connected coal inlet; the bottom of the furnace is equipped with an equal pressure air box, an air distribution plate and a wind cap; the main point is that there is a multi-pipe cyclone communicating with the upper flue of the furnace between the furnace and the vertical flue at the tail. Separation device, the top of the multi-pipe cyclone separation device communicates with the top of the tail vertical flue, and the bottom of the multi-pipe cyclone separation device communicates with the return port provided at the lower part of the furnace; the tail vertical flue is equipped with a section Connected high and low temperature convection tube bundles, the high temperature convection tube bundle at the upper part communicates with the ceiling tube through the radiation and convection connection header, and the low temperature convection tube bundle at the lower part communicates with the inlet header; the bottom of the vertical flue at the tail is provided There is an air preheater connected to the isobaric air box at the bottom of the furnace, and the air preheater is provided with a flue gas outlet connected to the bottom of the vertical flue at the tail.

The multi-pipe cyclone separation device includes a cyclone separator connected by an expansion joint and a blanking tube whose lower end communicates with the main jet pipe. An insulation tube is arranged outside the blanking tube. The pipe is connected, the auxiliary air inlet pipe is provided with a branch pipe, and the lower part of the blanking tube is provided with an auxiliary jet pipe; the lower end of the branch pipe is connected with the main jet pipe through the main electric damper, and the lower port of the main jet pipe is connected with the lower part of the furnace. The return port is connected.

The high and low temperature convection tube bundles are equipped with anti-wear covers, and the convection section connection headers are arranged between the high and low temperature convection tube bundles.

A flow equalizer is arranged in the inlet header.

Compared with the prior art, the utility model has the beneficial effects of simple structural assembly, convenient maintenance, obvious energy saving and consumption reduction effect, and solves the poor heat transfer effect caused by the irrational internal structure of the circulating fluidized bed organic heat carrier furnace in the prior art , The thermal efficiency decreases during long-term operation, it is difficult to repair when the interior is damaged, the frequency of damage is high, the trouble-free running time is short, and the return port is easily blocked.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a structural schematic diagram of the utility model;

Fig. 2 is a structural schematic diagram of the heat transfer oil inlet header;

Fig. 3 is the schematic diagram of returning material structure;

Fig. 4 is a schematic diagram of the structure of high and low temperature convection tube bundles;

Fig. 5 is a schematic diagram of an organic heat carrier circulation system;

Fig. 6 is a schematic diagram of the combustion system;

Figure 7 is a schematic diagram of the air preheater system.

In the figure 1, boiler base 2, equal pressure air box 3, air distribution plate 4, air cap 5, coal feeding port 6, material return port 7, furnace 8, coal hopper 9, main jet pipe 10, auxiliary jet pipe 11, main motor Damper 12, blanking cylinder 13, heat preservation cylinder 14, steel frame 15, auxiliary electric damper 16, auxiliary air inlet pipe 17, square plate radiation heating tube bundle 18, outlet header 19, cyclone separator 20, ceiling pipe 21, multi-pipe Cyclone separation device 22, expansion joint 23, thermal insulation refractory layer 24, vertical flue at the tail 25, radiation and convection connection header 26, high temperature convection tube bundle 27, convection section connection header 28, low temperature convection tube bundle 29, inlet header 30. Air preheater 31, flue gas outlet 32, equalizer plate 33, wear-resistant cover 34, heat utilization equipment 35, heat medium circulation pump 36, secondary air nozzle 37, primary fan 38, primary air air preheating inlet 39. Secondary fan 40. Secondary air preheating inlet 41. Secondary air duct 42. Primary air duct

Referring to Figure 1, Figure 1 is the boiler base, the utility model environmental protection and energy-saving circulating fluidized bed organic heat carrier boiler, including furnace 7 and tail vertical flue 24, around the furnace 7 and tail vertical flue 24 The insulation refractory material layer 23 and the steel frame 14 are respectively provided; the top of the furnace 7 and the vertical flue 24 at the tail are provided with a ceiling pipe 20, and one end of the ceiling pipe 20 communicates with the outlet header 18; the upper part of the inner wall of the furnace is provided with a square plate Radiation heating tube bundle 17; the lower part of the furnace is provided with a coal supply port 5 communicating with the coal hopper 8; A multi-pipe cyclone separation device 21 communicated with the flue at the upper part of the furnace 7 is provided, the top of the multi-pipe cyclone separation device 21 communicates with the top of the tail vertical flue 24, and the bottom of the multi-pipe cyclone separation device 21 is provided with the lower part of the furnace. The return port 6 is connected; the tail vertical flue 24 is provided with segmentally connected high and low temperature convection tube bundles 26, 28, and the high temperature convection tube bundle 26 on the upper part connects the header 25 with the ceiling tube 20 through radiation and convection. The low-temperature convection tube bundle located at the lower part communicates with the inlet header 29; the bottom of the vertical flue at the tail is provided with an air preheater 30 communicating with the isobaric air box 2 at the bottom of the furnace, and the air preheater 30 is provided with a vertical The flue gas outlet 30 connected to the bottom of the straight flue.

Referring to Fig. 1 and Fig. 3, the multi-pipe cyclone separation device includes a cyclone separator 19 connected by an expansion joint 22 and a blanking tube 12 whose lower end is communicated with the main jet tube 9, and an insulating tube 13 is arranged outside the blanking tube 12 , the top of the insulation tube 13 communicates with the auxiliary air inlet pipe 16 through the auxiliary electric damper 15, the auxiliary air inlet pipe 16 is provided with a branch pipe, and the bottom of the blanking cylinder 12 is provided with an auxiliary jet pipe 10; the lower end of the branch pipe The main electric damper 11 is connected with the main jet pipe 9, and the lower port of the main jet pipe 9 communicates with the material return port 6 at the lower part of the furnace.

Referring to Fig. 1 and Fig. 4, the high and low temperature convection tube bundles 26, 28 are provided with anti-wear covers 33, and a convection section connecting header 27 is arranged between the high and low temperature convection tube bundles.

Referring to FIG. 2 , a flow equalizer 32 is provided inside the inlet header 29 .

Design and working principle of the utility model:

The utility model boiler is divided into two parts, one is the furnace part, and the other is the vertical flue part at the tail. The furnace part chooses a reasonable cross-sectional area and a reasonable height. Plates and wind caps, the square plate radiation heating tube bundle is arranged at the position above 2.5m from the air distribution plate in the furnace part, and the heat preservation and refractory material is used below 2.5m, because the low-speed circulating fluidized bed is only worn below 1.5m from the air distribution plate. This arrangement is unlikely to cause wear and tear on the heating surface; a multi-pipe cyclone separation device is arranged between the vertical flue part and the furnace part at the tail, where the multi-pipe cyclone separation device is movably connected and easy to replace Controlling the flow rate of the flue gas, and its reasonable installation position and special structure can solve the problem of wear on the convection heating surface. A return system using the principle of jet flow is installed under the multi-tube cyclone separation device. The main ventilation pipe of the return system and the auxiliary The ventilation pipes pass through their respective electric dampers, and according to the actual situation, they are controlled by a microcomputer to automatically adjust their respective air intakes, so that the combustion temperature of the furnace can always be kept automatically within a reasonable range, preventing the heat transfer effect from being affected by slagging due to excessive furnace temperature. Burn out the heat exchange tubes in the radiant area. A high-temperature convection tube bundle, a low-temperature convection tube bundle, and an air preheater are installed in the vertical flue section at the tail. The high-temperature convection tube bundle and the low-temperature convection tube bundle are connected in sections, which is convenient for maintenance and replacement, solves the problem that some convection tubes are damaged and is difficult to repair, improves the running time of the circulating fluidized bed organic heat carrier furnace, and reduces maintenance costs. The convection area is connected in sections, and the convection tube bundles in the high and low temperature areas can adopt different structures according to their actual conditions, so that the smoke velocity and the oil velocity inside each convection tube bank in the high and low temperature areas are at a reasonable level. Within the range, improve the heat absorption effect.

Due to the wide adaptability and high combustion efficiency of circulating fluidized bed combustion coal, it is not only used in organic heat carrier boilers, but also widely used in industrial steam boilers, chemical roasting boilers, hot blast stoves, cement drying furnaces, and ceramic hot air boilers. Furnace etc. This kind of combustion method can solve the problem of a single type of fuel. More importantly, after adopting this technology, the coal saving can reach 15% to 30%. The economic loss is low, the operating cost is low, and the entire investment can be recovered within one year.

The multi-tube cyclone separation device is located between the vertical flue part at the tail and the furnace part and is easy to disassemble. When damaged, it can be quickly disassembled and repaired or replaced, reducing the economic loss caused by long-term shutdown; when part of the cyclone separation device in the multi-tube cyclone separation device When the ions are damaged, the unseparated part of the flue gas is directly discharged from the outlet of the cyclone separator. Due to the small diameter of the outlet of the cyclone separator, the flow rate of the flue gas is very fast, and the external space of the multi-pipe cyclone separation device is large. When the separated flue gas enters multiple When the pipe is in the external space of the cyclone separation device, the speed of the flue gas suddenly drops, and the material with large particles settles to the top of the multi-pipe cyclone separation device under the action of gravity, and the relatively clean flue gas enters the convection area, so that even if part of the cyclone in the multi-pipe cyclone separation device The damage of the separator will not wear the tube bundle of the convection heating surface, which prolongs the service life of the convection tube bundle and avoids a major shutdown accident caused by the wear of the convection heating surface tube bundle due to the damage of the multi-tube cyclone separation device. The reasonable installation position and special structure of the multi-tube cyclone separation device can avoid the wear of the flow heating surface, improve the running time and service life of the circulating fluidized bed organic heat carrier furnace, and reduce the maintenance and operation costs.

The material return system installed under the multi-tube cyclone separation device adopts the principle of jet flow at the position of the material port. The high-speed flow of air and the formation of a low-pressure area around the material port prevent the material port from being blocked. There is cold air outside the blanking cylinder, which can reduce the temperature of the blanking material, reduce the use of thermal insulation materials, and reduce the cost. The main ventilation pipe and auxiliary ventilation pipe of the feeding system pass through their respective electric dampers, and according to the actual situation, they are controlled by a microcomputer to automatically adjust their respective air intakes, so that the combustion temperature of the furnace can always be kept automatically within a reasonable range, and prevent the furnace from being damaged due to excessive temperature. Slagging improves the service life and thermal efficiency of the circulating fluidized bed organic heat carrier furnace.

The convection area of the utility model boiler, that is, the high and low temperature convection tube bundles is connected in sections, which is convenient for maintenance and replacement, and avoids the problem that the entire corresponding high and low temperature convection tubes cannot be used due to damage to the high temperature or low temperature part of the convection tubes. And when the high-temperature or low-temperature entire tube bundle is severely damaged, only the corresponding high-temperature or low-temperature tube bundle is replaced, and other tube bundles can be used normally, avoiding replacement of all convective heating surfaces, and reducing maintenance costs. The convection area is connected in sections, so that the convection tube bundles in the high and low temperature areas can adopt different structures according to their actual conditions, so that the smoke velocity and the oil velocity inside each of the convection tube bundles in the high and low temperature areas are at a reasonable level. Within the range, the heat absorption effect is improved, and the thermal efficiency of the circulating fluidized bed organic heat carrier furnace is improved as a whole.

The inner diameter cross-sectional area of the inlet header on the boiler of the utility model is 1-3 times of the sum of the cross-sectional areas of all openings on the inlet header, and an equalizing plate is installed inside. Choose a reasonable diameter of the inlet header by 1-3 times the sum of the hole cross-sectional area, and choose a suitable installation angle for the equalizer in the range of 0-90°, so as to ensure the same flow velocity in each convection tube bundle and solve the drift question. The utility model avoids safety accidents, improves the running time of the boiler, and reduces economic losses.

The utility model mainly constitutes the main functions and innovations of the system:

The organic heat carrier circulation system of the present utility model, as shown in Figure 5, the organic heat carrier is input into the inlet header 29 through the heat medium circulating oil pump 35, and the inlet header 29 is connected with the low-temperature convection tube bundle 28; as shown in Figure 2, the heat transfer oil inlet header As shown in the schematic diagram of the tank structure, the equalizer plate 32 inside the inlet header 29 can ensure the same flow rate of the organic heat carrier entering the low-temperature convection tube bundle 28, avoiding the technical problem of partial convection tube burnout due to diversion. Each convection tube bundle is connected through the convection section connection header 27, and after heat exchange with the flue gas by the low-temperature convection tube bundle 28, it enters the high-temperature convection tube bundle 26 to continue heat exchange with the flue gas; As shown, in order to facilitate maintenance and improve the heat absorption effect, the high-temperature convection tube bundle 26 and the low-temperature convection tube bundle 28 are fabricated in sections. When some of the convection tubes are damaged, find the corresponding convection tube bundle, quickly disassemble and repair, shorten the shutdown time, and reduce the economic loss caused by the shutdown. And the high-temperature convection tube bundle 26 and the low-temperature convection tube bundle 28 can adopt different structures according to their respective actual conditions, so that the smoke velocity and the oil velocity inside each convection tube bundle in the high and low temperature regions are all within a reasonable range, improving the absorption rate. heat effect. Finally, through the radiation and convection connection header 25, it enters the square plate radiation heating tube bundle 17 to fully absorb heat in the furnace part 7, and finally passes through the top heating surface 20 from the outlet header 18 to the heat utilization equipment 34, and then returns to reheat.

The combustion system of the present utility model, as shown in Figure 6, is mainly composed of a boiler base 1, a furnace 7, a multi-tube cyclone separation device 21, a material return port 6, an air preheater 30, etc., and the bottom of the furnace 7 is In the dense phase material layer, the bottom is the air distribution plate 3, and the air distribution plate 3 is evenly arranged with the air cap 4, and the primary air passing through the air preheater 30 enters the furnace 7 evenly from the air distribution plate 3 through the equal pressure air box 2 through the air distribution plate 3, The fuel and limestone mixture is sent to the coal hopper 8 through the spiral coal feeder, and the secondary air accounts for about 40% of the total air volume, and enters the furnace 7 from the secondary air nozzle 36 and the coal feeding port 5 respectively; The first, middle and lower layers are arranged to facilitate combustion and furnace temperature control and reduce _NOx emissions. When the Ca/S ratio is 1.5-2.5, the desulfurization efficiency can usually reach 90%; the whole combustion is carried out under low fluidization wind speed, and the furnace temperature is controlled at 900°C. After the flue gas comes out of the furnace 7, it entrains a large amount of particulate materials The cyclone separator 19 entering the high-temperature multi-tube cyclone separation device 21, the cyclone separator 19 is cast from high-temperature resistant and wear-resistant cast steel, and the multi-tube cyclone separation device 21 is located in the middle of the vertical flue part 24 at the tail and the furnace 7 , and is easy to disassemble, the separated particles return to the furnace through the blanking tube 12 through the return port 6 for re-combustion; Separator 19 is discharged from the outlet. Because the cyclone separator 19 has a small outlet diameter, the flue gas velocity is very fast, and the external space of the multi-pipe cyclone separation device 21 is very large. When the separated flue gas enters the multi-pipe cyclone separation device 21 external space, the smoke The gas velocity drops suddenly, and the material with large particles settles to the top of the multi-pipe cyclone separation device 21 under the action of gravity. Damage will not wear the convection heating surface tube bundle. The flue gas leaving the multi-pipe cyclone separation device 21 enters the tail vertical flue 24, and the fine particles discharged along with the flue gas can be collected by the dust collector equipment at the rear of the boiler.

The material return system of the present utility model, as shown in the structure diagram of the material return system in Fig. Jet pipe 10, expansion joint 22 is mainly to prevent unnecessary loss caused by high temperature expansion of the return system. The cold air outside is divided into two parts, one part enters the insulation cylinder 13 tangentially through the auxiliary electric damper 15 and auxiliary jet pipe 16, and the cold air It rotates downward around the blanking cylinder 12 while exchanging heat with the high-temperature particles in it to become high-temperature pores, which incline downward from the auxiliary jet tube 10 and flow into the blanking cylinder 12 at high speed. Another part of cold air directly enters the main jet pipe 9 through the main electric damper 11 and mixes with the hot air flowing out from the auxiliary jet pipe 10 and the particles falling from the blanking barrel 12, and flows to the return port 6 at a high speed to enter the furnace. The high-speed airflow in the auxiliary jet tube 10 and the main jet tube 9 forms a low-pressure zone near the bottom port of the blanking tube 12 (jet flow principle), which avoids the phenomenon of material blocking; and the microcomputer adjusts the main electric damper 11 and the auxiliary electric damper 15 according to the actual situation. Allocate a reasonable air volume to ensure that the combustion temperature of the furnace is always automatically maintained in a reasonable range to avoid coking in the furnace due to excessive furnace temperature.

The air preheater system of the present utility model, as shown in Figure 7, the air preheater of this furnace is a two-stage arrangement of tubular air preheaters 30, the upper stage is the primary air air preheating inlet 38, and the lower stage is the secondary air Air preheating inlet 40, air is sent in by primary fan 37 and secondary fan 39 respectively. The flue gas of the air preheater 30 flows from top to bottom in the pipe, and the air scours laterally outside the pipe. After two strokes, it enters the primary air duct 42 and the secondary air duct 41 respectively, and the preheating temperatures reach 180°C and 120°C respectively. ℃. In order to make the tube box expand freely in the hot state, an expansion joint is installed on the upper part of the tube box.

Claims (4)

1. an environmental protection and energy saving circulating fluid bed organic heat carrier boiler comprises the vertical flue of burner hearth and afterbody, is respectively equipped with thermal insulation fire-resistant material layer and steelframe around said burner hearth and the vertical flue of afterbody; The top of said burner hearth and the vertical flue of afterbody is provided with roof tube, and an end of roof tube is communicated with outlet collection case; The top of said inboard wall of burner hearth is provided with the square plate radiation tube bank of being heated; The bottom of said burner hearth is provided with the coal feeding hole that is communicated with coal bunker; The bottom of said burner hearth is provided with isobaric bellows, air distribution plate and blast cap; It is characterized in that being provided with the Mutlicyclone plant that is communicated with the upper furnace smoke outlet flue between the vertical flue of said burner hearth and afterbody; The top of Mutlicyclone plant is communicated with the top of the vertical flue of afterbody, and the bottom of Mutlicyclone plant is communicated with the returning charge mouth that lower furnace portion is provided with; Be provided with the high and low temperature convection bank that segmentation connects in the vertical flue of said afterbody, superposed high temperature convection bank is connected the collection case through radiation and is communicated with said roof tube with convection current, and the low temperature convection bank that is positioned at the bottom is communicated with the inlet header case; The bottom of the vertical flue of said afterbody is provided with the air preheater that is communicated with the isobaric bellows of burner hearth bottom, and air preheater is provided with the exhanst gas outlet that is communicated with the vertical flue of afterbody bottom.

2. environmental protection and energy saving circulating fluid bed organic heat carrier boiler according to claim 1; It is characterized in that said Mutlicyclone plant; Comprise the blanking barrel that cyclonic separation is sub and the lower end is communicated with the power stream pipe that is connected by expansion joint, the blanking barrel outside is provided with heat-preservation cylinder, and the top of heat-preservation cylinder is communicated with auxiliary blast pipe through auxiliary MOD; Be provided with branched pipe below the auxiliary blast pipe, the bottom of blanking barrel is provided with the assisted jet pipe; The lower end of said branched pipe is connected with the power stream pipe through main MOD, and the lower port of power stream pipe is communicated with the returning charge mouth of lower furnace portion.

3. environmental protection and energy saving circulating fluid bed organic heat carrier boiler according to claim 1 is characterized in that said high and low temperature convection bank peripheral hardware abrasionproof cover, is provided with convection section between the high and low temperature convection bank and connects the collection case.

4. environmental protection and energy saving circulating fluid bed organic heat carrier boiler according to claim 1 is characterized in that establishing homogenizing plate in the said inlet header case.

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