CN2757083Y

CN2757083Y - Heat pipe air preheater

Info

Publication number: CN2757083Y
Application number: CN 200420065373
Authority: CN
Inventors: 陈世醒; 唐伟; 刘志伟
Original assignee: Liaoning Shihua University
Current assignee: Liaoning Shihua University
Priority date: 2004-06-12
Filing date: 2004-06-12
Publication date: 2006-02-08
Anticipated expiration: 2014-06-12

Abstract

The utility model relates to a heat pipe air preheater for recovering residual heat of fume of heating furnaces. The utility model is used for fields of petrochemical engineering, metallurgy, etc. The utility model is composed of a heat pipe (2) which is provided with high and low fins (1) with different diameters, a fume inlet (3), a fume outlet (4), an air inlet (5), an air outlet (6), a heating section (7) and a cooling section (8). The utility model uses a top arrangement type or a floor type according to field conditions, utilizes the high-efficiency heat transfer element of heat pipe to recover the residual heat of the fume to heat air in the furnaces, and realizes the purpose of energy saving.

Description

Heat-pipe air preheater

One, technical field

The utility model relates to a kind of flue gas waste heat recovery apparatus, mainly proposes a kind of heat-pipe air preheater.

Two, background technology

Heat pipe preheater is widely used in the waste heat of flue gas of heating furnace removal process because its heat transfer coefficient is big, compact conformation, be convenient to advantages such as single tube dismounting, light and flexible.In order to increase the convection heat transfer' heat-transfer by convection of outer flue gas of pipe and tube wall, take heat pipe to add the method for fin usually, make with the heat transfer area after the fin to increase, thereby make the corresponding increase of rate of heat transfer than tens times of light pipes, tens times of ground.Conventional method is to adopt contour (directly) and arrange fin very closely, because the scale formation of flue gas is more serious, special under the situation of fuel oil, the fin outer rim is close to curvature portion and is covered by cigarette ash soon, and then corroded by crock, greatly influenced heat-transfer effect.In order to address this problem, existing unique way is provided with the plurality of rows soot blower at the heating surface bank interbody spacer exactly, and the site operation personnel opens once every several hrs, to reach the purpose of removing dust stratification.But arrange the setting of soot blower more, increased the cost of air preheater, influenced the compactedness of equipment, increased power consumption, and effect is not very good.The utility model tries hard to increase the disturbance of flue gas at fin surface by changing the method for fin structure and surface appearance, delays the fouling process, strengthens the convection heat transfer' heat-transfer by convection between flue gas and fin.

Three, summary of the invention

The purpose of this utility model provides a kind of heat-pipe air preheater that field waste heat of flue gas of heating furnace such as petrochemical industry, metallurgy reclaim that is widely used in, it is characterized in that: the fin that the unified highly ring-type fin of (diameter) of heat pipe bringing-up section and cooling section routine is changed into differing heights (diameter), and take high and low fin form alternately, heat pipe fin surface crock generates too fast drawback to overcome in the past.The bringing-up section and the cooling section of heat pipe are equipped with different-diameter, and high and low alternate fin, fin thickness are 1～2mm, highly are 14～20mm, and spacing is 6～10mm, and high and low fin height difference is 3～10mm.See Fig. 1.When flue gas flows through injustice straggly surperficial, the disturbance aggravation, suppressed the generation of flue gas dirt, attenuate the thickness of fin surface viscous flow bottom, heat transfer resistance is significantly reduced, strengthened the convection heat transfer' heat-transfer by convection of flue gas and fin surface, heat transfer efficiency is improved greatly, save a large amount of fuel oil (gas), thereby receive obvious energy-saving effect.

The related heat pipe intraductal working medium of the utility model is a water.In order to prevent water and steel pipe reaction generation on-condensible gas influence heat transfer under the high temperature, be added with the corrosion inhibiter of the patentee's development in the water.This corrosion inhibiter can make the heat pipe inwall generate one deck compact protective film, stoped the reaction of working-medium water and tube wall under the high temperature.

According to field condition and technological requirement, the heat-pipe air preheater mount scheme can adopt overhead type (be that heat exchange of heat pipe is placed on the heating furnace furnace roof, its fire end places the convection section in the heating furnace) or console mode.Because of this heat pipe belongs to gravity type, when taking overhead type to place, the inclination that will keep 10 degree at least.

Four, description of drawings

Fig. 1 is the heat-pipe air preheater structural representation;

Fig. 2 is for having the heat pipe schematic diagram of high and low alternate (bringing-up section is 2,2 alternate, and cooling section is 1,1 alternate) fin.

Five, the specific embodiment

The heat-pipe air preheater that the utility model relates to, by different-diameter is housed, the heat pipe (2) of high and low alternate fin (1) and smoke inlet (3), exhanst gas outlet (4), air intake (5), air outlet slit (6), bringing-up section (7), cooling section (8) are formed.

At first according to the condition at scene and the mount scheme of technological requirement selection heat-pipe air preheater: overhead type can make full use of the draft of chimney nature, avoid adopting air-introduced machine, flue is simplified, but chimney raft is required than higher, and heat pipe to keep the above inclination of 10 degree; Adopt when console mode mostly is old furnace modification, heat pipe is vertically placed, owing to use air-introduced machine, can adopt bigger flow velocity, and heat transfer coefficient height and operation scheme are flexible, the heat-pipe air preheater of can stopping using at any time in case of necessity.

The key that the related heat-pipe air preheater of the utility model is implemented is the making and the installation of heat pipe and fin.The manufacturing process of heat pipe comprises following several steps: alkali cleaning, pickling tubing-rust cleaning oil removing-clear water flushing-passivation film-welding bottom end cover-charge into working medium (filling amount is 30～35% of the pipe internal volume)-welding bottom end cover-thermal exhaust-seal-check vacuum.

At first to determine the various structural parameters such as height, thickness, spacing of fin during the outer fin of mounting pipe according to process conditions, and then select the arrangement mode of high and low fin according to the flow velocity of flue gas and degree of purity (combustion position and contain what of corrosive gas): for bringing-up section, when fuel is Device in Gas, adopt 1,1 or 2,2 alternately; When fuel is residual oil, adopt 2,2 or 3,3 alternately; Cooling section takes 1,1 or 2,2 to arrange because air ratio is clean usually.The installation form of fin can adopt wear sheet, around sheet, soldering lug or ratio-frequency welding flight any one.

Claims

1, a kind of heat-pipe air preheater that is used for the waste heat of flue gas of heating furnace recovery, by different-diameter is housed, the heat pipe (2) of high and low alternate fin (1) and smoke inlet (3), exhanst gas outlet (4), air intake (5), air outlet slit (6), bringing-up section (7), cooling section (8) are formed, it is characterized in that: the bringing-up section and the cooling section of heat pipe are equipped with different-diameter, high and low alternate fin, fin thickness is 1～2mm, highly be 14～20mm, spacing is 6～10mm, and high and low fin height difference is 3～10mm.

2, heat-pipe air preheater according to claim 1, its feature also is: when fuel was Device in Gas, the high and low fin of bringing-up section can adopt 1,1 or 2,2 alternately.

3, heat-pipe air preheater according to claim 1, its feature also is: when fuel was residual oil, the high and low fin of bringing-up section should adopt 2,2 or 3,3 alternately.