Mixed composite phase change heat exchanger
Technical field
The present invention is a kind of mixed composite phase change heat exchanger that is applied to boiler, Industrial Stoves and the hot equipment of chemical industry, particularly to the improvement of air preheater and economizer structure.
Background technology
No. 992263808 patent disclosures of ZL a kind of overall thermal tubular type complex phase-change heat exchanger, its structure is, by upper and lower header, finned tube, tube connector and drum are formed the phase-change heat-exchanger that an inner chamber is communicated with; Fill in the inner chamber with an amount of phase transformation medium; The dividing plate at finned tube middle part will be divided into air channel and gas flue two parts up and down, form the low-temperature zone of air preheater; Coil pipe is housed in the drum, has cold water to flow through in the coil pipe and form a water heater.On the row's finned tube of end, land surface pyrometer is housed, according to the aperture of the wall temperature autocontrol panel water inlet tube valve that records.Overall thermal tubular type complex phase-change heat exchanger can be when reducing exhaust gas temperature significantly, makes the heating surface wall temperature remain on temperature a little more than flue gas dew point; And set value adjustable controlled according to wall temperature.But the complex phase-change heat exchanger of this structure, the hot water temperature who exports from coil pipe generally is no more than 70 ℃, and requires bigger adjusting discharge.Limited and when need obtaining higher hot water temperature, this equipment is just powerless, shows tangible deficiency when the adjusting discharge that provides, it is very difficult improving temperature; It is worthy of note that present technical barrier is the water temperature raising to be surpassed 70 ℃ be difficult to accomplish that if the hot water temperature can be brought up to about 100 ℃, this has crossed over a step again on the technique direction of low temperature heat energy utilization.
Summary of the invention
The objective of the invention is, overcome the shortcoming that above-mentioned prior art exists, provide a kind of water temperature is improved to surpass 70 ℃ mixed composite phase change heat exchanger.
Structure of the present invention is, mixed composite phase change heat exchanger includes the phase-change heat-exchanger 14 that inner chamber that phase transformation section upper header 7, lower collecting box 15, finned tube 17, tube connector 3 and drum 4 form is communicated with; External partition 11 is divided into two sections with finned tube, and top is air channel 2 and air outlet slit 26, air intake 10, and the bottom is gas flue 20 and smoke inlet 19, exhanst gas outlet 13; There is fluid media the bottom of finned tube inner chamber, and top is gaseous medium; Coil pipe 6 is contained in the drum 4; The top that needle-valve 5 is installed in drum is characterized in that also having high-temperature water heater 18; The high-temperature water heater is communicated with by upper header 21, lower collecting box 16 and finned tube 17 and forms; The high-temperature water heater is positioned at a side of the smoke inlet 19 of phase-change heat-exchanger 14, and internal partition 23 is separated into water inlet 24 and delivery port 22 two parts with upper header; Delivery port 22 is communicated with hot water delivery pipe road 25, and water inlet 24 is communicated with coil pipe 6.
Operation principle of the present invention is, in the inner chamber of phase-change heat-exchanger 14, fill with an amount of phase transformation medium, finned tube 17 partially absorbs flue gas heat in gas flue 20, make medium generation steam and rising in the pipe, make the finned tube on top heat air flowing in the air channel 2, become the low-temperature zone of boiler air preheater.Unnecessary steam rises to drum 4 again after adding hot-air, and the cold water that flows through in the heat(ing) coil 6 is as low-temperature water heating device of the present invention.The hot water that is heated to a certain medium temperature continues to be subjected to the flue gas heating after delivery port 22 is discharged through the finned tube 17 that water inlet 24 enters high-temperature water heater 18 again.The pressure limiting scope of the spring valve 1 in the hot water delivery pipe road 25 can not be vaporized when guaranteeing that the hot water temperature reaches 105 ℃ about 0.1MPa.Entire equipment structure and the hot water temperature in each section is all determined by optimal design, is made the integrated objective function of weight of equipment and flue gas flow resistance reach minimum.
Because structure of the present invention can make the hot water temperature reach 105~110 ℃ easily, this has just solved the existing problem of present prior art, and not grey the blocking up of equipment do not corroded, reliable operation, service life, energy-saving effect was remarkable more than 4 years, and equipment investment generally can be regained in half a year.
Description of drawings
1 spring valve, 2 air channels, 3 tube connectors, 4 drums, 5 needle-valves, 6 coil pipes, 7 phase transformation section upper headers, 8 control valves, 9 wall temperature automatic controllers, 10 air intakes, 11 external partitions, 12 land surface pyrometers, 13 exhanst gas outlets, 14 phase-change heat-exchangers, 15 phase transformation section lower collecting box, 16 high-temperature water heater's lower collecting box, 17 finned tubes, 18 high-temperature water heaters, 19 smoke inlets, 20 gas flues, 21 high-temperature water heater's upper headers, 22 delivery ports, 23 internal partitions, 24 water inlets, 25 hot water delivery pipe roads, 26 air outlet slits.
Accompanying drawing is a structural representation of the present invention.
The specific embodiment
Mixed composite phase change heat exchanger includes the phase-change heat-exchanger 14 that inner chamber that phase transformation section upper header 7, lower collecting box 15, finned tube 17, tube connector 3 and drum 4 form is communicated with; External partition 11 is divided into two sections with finned tube, and top is air channel 2 and air outlet slit 26, air intake 10, and the bottom is gas flue 20 and smoke inlet 19, exhanst gas outlet 13; There is fluid media the bottom of finned tube inner chamber, and top is gaseous medium; Coil pipe 6 is contained in the drum 4; The top that needle-valve 5 is installed in drum is characterized in that also having high-temperature water heater 18; The high-temperature water heater is communicated with by upper header 21, lower collecting box 16 and finned tube 17 and forms; The high-temperature water heater is positioned at a side of the smoke inlet 19 of phase-change heat-exchanger 14, and internal partition 23 is separated into water inlet 24 and delivery port 22 two parts with upper header; Delivery port 22 is communicated with hot water delivery pipe road 25 by spring valve 1, and water inlet 24 is communicated with coil pipe 6.Coil pipe is communicated with control valve 8; Wall temperature automatic controller 9 is connected with land surface pyrometer 12 and control valve 8 by circuit; Land surface pyrometer is installed on end row's finned tube at exhanst gas outlet 13 places.Be contained in the last land surface pyrometer of arranging on the finned tube 12 and the wall temperature signal that records adjusted the aperture of cold water pipes adjusted valve 8 by wall temperature automatic controller 9, thereby the heating surface minimum wall temperature that guarantees phase-change heat-exchanger 14 and high-temperature water heater 18 all is higher than the flue gas dew point temperature, reaches the performance indications that prevent cold end corrosion that the present invention has.The needle-valve 5 at drum 4 tops has prevented the aging of phase-change heat-exchanger as getting rid of on-condensible gas and additional phase transformation medium.