CN1285874C

CN1285874C - Heat exchange system using maltiple L valve distribution

Info

Publication number: CN1285874C
Application number: CN 02156621
Authority: CN
Inventors: 张�诚
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-12-17
Filing date: 2002-12-17
Publication date: 2006-11-22
Anticipated expiration: 2022-12-17
Also published as: CN1514200A

Abstract

The present invention relates to a heat exchange system using the residual heat of high-temperature hot fume to preheat air, particularly to a cloud dropping bed heat exchange system using a plurality of L valves to realize the counterflow heat exchange between solid particles uniformly distributed and high-temperature fume. The heat exchange system comprises a cylindrical barrel body cloud dropping bed. High-temperature fume enters from the lower part of the bed and flows from bottom to top, and solid particles drop from the top of the bed. The heat exchange system uses a partitioned L valve group material distributor composed of a plurality of L valves to control material distribution. The cylindrical barrel body cloud dropping bed is divided into three to eight partitions according to the diameter, and three to twenty material distribution L valves are arranged in each partition. Each L valve is composed of a vertical material dropping pipe and a horizontal channel. The length L of a horizontal section is controlled to be three times of the diameter D about, and the lower part of the vertical material dropping pipe is provided with an air injection pipe. The material flow rate of the L valves is controlled by the quantity of injected air, and the quantity of dropping materials can be regulated by regulating the quantity of injected air of each partition. Correspondingly, fully circumferential air ejection is adopted in an air outlet beside a dropping material point. A thermometer is respectively arranged at corresponding air outlets of partitions to increase feeding quantity of partitions with high air ejection temperature and to reduce feeding quantity of partitions with low air ejection temperature for keeping balance. Compared with ordinary L valves, the L valves in the heat exchanged system have the difference that outlets of the L valves are respectively provided with a vertical straight pipeline, air and materials are separated at the vertical straight.

Description

The cloud bed heat-exchange system that falls with a plurality of L valve clothes

Technical field

The present invention is a kind of heat-exchange system that utilizes elevated temperature heat fume afterheat preheated air, particularly realizes the solid particle of uniform distribution and the cloud bed heat-exchange system that falls of high-temperature flue gas countercurrent flow with a plurality of L valves.

Background technology

Utilization is the important means of saving energy in kiln with air preheat with the high-temperature flue gas heat that reclaims various kilns.Tubular type commonly used and rotary regenerative air preheater all transmit heat by metal, and the temperature of institute's preheated air is limited by the heat-resisting degree of metal.Carbon steel preheater hot blast temperature is no more than 400, and is too expensive with heating resisting metal.For improve hot blast temperature commonly used be the hot-blast stove of constructing with refractory material, it realizes heat exchange by intermittently switching the ventilation direction, its volume is very big, and is a lot of with material, and hot blast temperature is cyclic fluctuation.Doing solid thermal carriers with particle has two kinds of forms with the heat exchange of fluid bed form in fume side, and a kind of is downflow type, and promptly particle is fed by temperature end, is heated with flow of flue gas, after separated device separates, changes another bubbling bed and air over to and does the cross-current heat exchange.The mean temperature difference of following current heat exchange is little, and the particle outlet temperature is low, so hot blast temperature is low; Another kind is reverse-flow, be that particle falls from top to bottom with the cloud form that falls, air-flow from bottom to top, its relative velocity is the particle limit, and sinking speed numerical value height, heat transfer coefficient are also just high, and particle is warm eventually in the fume high-temperature district, eventually temperature is high, and mean temperature difference is big, is that a kind of people wish the heat transfer type realized very much.The cloud bed heat-exchange system that falls is strong to dusty gas adaptability, yet the difficult point of gas-solid countercurrent flow is how to make uniform particles to be distributed in the air-flow.Practice finds, particle is in case poly-group only just is difficult to it is disperseed by air-flow, and gas more becomes to flowing to the sparse zone of air, and therefore, the target of the good contact of gas-solid is difficult to realize.

Summary of the invention

The object of the present invention is to provide a kind of cloud bed heat-exchange system that falls of realizing a plurality of L valve of the usefulness cloth of uniform distribution.

For achieving the above object, technical solution of the present invention is:

The cloud bed heat-exchange system that falls of a plurality of L valve of a kind of usefulness cloth, this system comprises the cloud bed that falls that a cylindrical tube constitutes, and the cloud bed bottom that falls is provided with high-temperature flue gas entry, and the described cloud bed that falls circumferentially is divided into several cloth districts, is distributed with several clothes L valve in each district.

Further, the heat exchanger gas vent of the described cloud bed that falls adopts radial giving vent to anger of full week, and corresponding each cloth district is provided with an Outlet Gas Temperature measuring point, the aeration quantity of regulating corresponding district according to outlet air temperature, and then regulate feeding coal.

Further, the Horizontal Exit place of described L valve is a straight-through up and down vertical pipe, and last hole is used to give vent to anger, and following hole is used for blanking, and material-dropping hole adopts the flaring channel design of being made up of center inner cone and outer cone.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the cutaway view of L valve of the present invention;

Fig. 3 is the cutaway view of blanking port of the present invention.

The specific embodiment:

The present invention at first comprises the cloud bed that falls, and is generally cylindrical tube, and as shown in Figure 1, high-temperature flue gas 2 is entered by the bottom, flows from bottom to top.Solid particle is fallen by bed top 4.It is considered herein that the uniformity that initially feeds solid particle and adjacent with it exhanst gas outlet structure are most important.General structure distributing device is difficult to continuous firing at high temperature, in case find that inequality also is difficult to regulate.The L valve group distributing device 6 control clothes that the present invention advises using a plurality of L valves 5 of subregion to constitute.Look cloud bed diameter and be divided into 3-8 district, in each district 3-20 cloth L valve arranged at circumferencial direction.So-called L valve is made up of a vertical material blanking tube and a horizontal channel, and control horizontal section length L is about three times of diameter D, and an air injection pipe is arranged in the material blanking tube bottom.The mass flow of L valve is controlled by gas injection rate, regulate the gas injection rate 7 in each district and just can regulate the blanking amount, be engaged near the gas outlet 8 of discharging point with it and should adopt radial giving vent to anger of full week, establishing the higher district of 19 pairs of air outlet temperatures of thermometer in corresponding gas outlet, each district should increase feeding coal, and the district that temperature is on the low side should reduce feeding coal makes it balanced as far as possible.Different with general L valve, it is that a straight vertical is threaded a pipe that the present invention requires L valve outlet port place, and gas so far separates with material, and gas is got rid of by the sky, and close dense material is fallen by downward hole, as shown in Figure 2.For the supplied materials that guarantees the L valve can not interrupt, should there be the enough big feed bin of a capacity 10 top of L valve.The high-temperature material that is fallen by the cloud bed that falls is concentrated to send into a J type valve 11, enter bubbling bed air heater 12 by J type valve material, cryogenic particles by the bubbling bed flows out enters material lifting device 14 by another J valve 13, the feed bin of the referred L valve of material distributing device top.Certainly high-temperature material also can be raised earlier, separates the back and enters bubbling bed air heater by another J valve, and the cryogenic particles that is flowed out by the bubbling bed directly enters high hopper.Nature, the empty tower gas velocity of bubbling bed will be lower than the empty tower gas velocity of cloud bed, and generally calculating the former by mark attitude aerodromometer is the latter's 30-60%, and the terminal falling velocity of particle is between two superficial linear velocity in a columns.

30000Nm is for example arranged ³/ h1100 ℃ flue gas is used to heat already that tubular preheater is preheating to 350 ℃ same amount air, and selecting particle diameter is that particles such as the bauxite of 1-1.3mm or Coaseries kaolin are made heat carrier, and the cloud bed net heat that falls exchange highly is 12m, and diameter is 3.5m.Cloth adopts 6 subregions, 61 L valve cloth tubes.The exhanst gas outlet temperature is 700 ℃, and particle is 1000 ℃ from bed tempertaure, and through promoting and bubbling bed air heater, particle temperature has been lowered to 600 ℃, and air is heated to 750 ℃.The recycle stock amount is 50t/h.As shown in Figure 3, material-dropping hole adopts the flaring channel design of being made up of inner cone and outer cone.

Claims

1, the cloud bed heat-exchange system that falls of a plurality of L valve of a kind of usefulness cloth, it is characterized in that this system comprises the cloud bed that falls that a cylindrical tube constitutes, the cloud bed bottom that falls is provided with high-temperature flue gas entry, the described cloud bed that falls circumferentially is divided into several cloth districts, is distributed with several clothes L valve in each district.

2, the cloud bed heat-exchange system that falls of a plurality of L valve of usefulness as claimed in claim 1 cloth, it is characterized in that, the heat exchanger gas vent of the described cloud bed that falls adopts radial giving vent to anger of full week, corresponding each cloth district is provided with an Outlet Gas Temperature measuring point, regulate the corresponding aeration quantity of distinguishing according to outlet air temperature, and then regulate feeding coal.

3, the cloud bed heat-exchange system that falls of a plurality of L valve of usefulness as claimed in claim 1 cloth, it is characterized in that the Horizontal Exit place of described L valve is a straight-through up and down vertical pipe, last hole is used to give vent to anger, following hole is used for blanking, and material-dropping hole adopts the flaring channel design of being made up of center inner cone and outer cone.