CN201059900Y - Combined heat pipe flue gas condensation economizer - Google Patents

Abstract

The combined heat pipe flue gas condensing economizer relates to a fuel oil and gas boiler flue gas waste heat utilization device, which is a high-efficiency energy-saving device that fully utilizes the sensible heat and latent heat of the flue gas. The equipment includes four parts: evaporation box, condensation box, connecting pipe, and condensate collection and discharge device. Its structural features are: the inside of the evaporation box is a serpentine coil, and the tube is a finned tube; Inside the box is a serpentine coil, the tube is a finned tube, and the material is copper, stainless steel, carbon steel; the connecting pipe connects the finned tube in the evaporating box and the condensing box, and is divided into an ascending pipe and a descending pipe; the condensate is collected The discharge device is set at the lower part of the evaporation box, mainly collecting and discharging the condensed water in the evaporation box, and the material is ordinary carbon steel. Working characteristics: the flue gas enters the evaporation box and flows outside the tube, and the tube is the working medium of the heat pipe; the cooling water or cooling air enters the condensation box, flows outside the tube, and the inside of the tube is the working medium of the heat pipe; the flue gas enters the evaporation box and puts the finned tube inside When the working fluid is heated, the temperature of the flue gas is lowered, and the water vapor in the flue gas condenses to form condensed water, which is collected and discharged by the condensate collection device. The inner finned tube transfers heat to the cooling water or cooling air through the tube wall, heats the cooling water or heats the cooling air, and the steam in the tube condenses to form a liquid working medium, which flows back to the evaporation tank from the downcomer; the heated cooling Water or cooling air can be utilized. The flue gas has both sensible heat release and latent heat release of water vapor in the equipment, which improves the utilization efficiency of the waste heat of the flue gas.

Description

Combined heat pipe flue gas condensation economizer

Technical field

The utility model relates to a flue gas residual heat utilization device for fuel oil and gas boilers, which is a combined heat pipe flue gas condensation energy-saving device which fully utilizes the sensible heat and latent heat of the flue gas.

Background technique

Fuel oil and gas contain a lot of hydrogen, which makes the exhaust gas of fuel oil and gas boilers contain a lot of water vapor. The exhaust gas temperature of oil-fired and gas-fired boilers is relatively high, generally above 150°C, and the flue gas carries away a large amount of physical sensible heat and latent heat of vaporization. At present, the equipment for waste heat utilization of oil-fired gas-fired boilers mainly utilizes the sensible heat of boiler flue gas, and does not fully utilize the latent heat of flue gas. The flue gas of oil-fired and gas-fired boilers contains a large amount of water vapor, and recycling the latent heat of water vapor in the flue gas can effectively improve the efficiency of the boiler. At present, the types of equipment for recovering waste heat from flue gas are mainly water tube heat exchangers and smoke tube heat exchangers. The water tube heat exchanger mainly has the following disadvantages: the resistance of the flue is greatly increased, which affects the working performance of the burner; the water flows in the pipe, and the flue gas flows outside the pipe. In order to avoid corrosion, more corrosion-resistant materials are required and the cost is higher ; The heat exchanger is arranged in the flue as a whole, which increases the difficulty of construction and maintenance. The flue tube heat exchanger mainly has the following disadvantages: In order to overcome the corrosion of the flue gas on the rear flue, a bypass flue must be arranged so that part of the flue gas directly passes through the bypass flue and mixes with the cooled flue gas. exhaust, which reduces the efficiency of waste heat utilization; the flue gas is discharged after passing through the tube, only one pass, and the heat exchange efficiency is not high; the heat exchanger is arranged in the flue as a whole, which increases the difficulty of construction and maintenance; the bypass flue Arrangement increases the cost. Regardless of the water tube heat exchanger or the smoke tube heat exchanger, the heat transfer coefficient is small and the heat exchange area is large, resulting in a large equipment volume and a large floor space.

Heat pipes are one of the most efficient heat transfer elements, relying on the phase change of the working fluid inside the heat pipe to achieve heat transfer. Heat pipe research originated in the United States in the 1940s, and was applied to space technology in the 1960s, which attracted the former Soviet Union, Britain, Italy, and former West Germany to actively engage in research and development of heat pipe technology. In the 1970s, heat pipe technology developed rapidly. After the 1990s, heat pipe technology began to play a role in various civilian fields. my country started the research on heat pipe technology in the 1970s, mainly focusing on the application research of space technology and electronic components cooling. In the late 1980s, the research on heat pipe technology began to turn to the research on energy utilization and energy saving technology. With the in-depth research and development, heat pipe technology has been widely used in various fields such as energy, chemical industry, transportation, electronics, and construction. With the improvement of science and technology level and the change of social demand, the field of research and development of heat pipe technology will continue to expand. The whole heat pipe can be divided into three parts: evaporation section, adiabatic section and condensation section. The working fluid absorbs heat in the evaporation section and vaporizes into steam. Under the action of micro-pressure difference, the steam enters the condensation section through the adiabatic section in the steam channel in the tube cavity. In the condensation section, the steam releases heat and condenses to form a condensate. Under the capillary force of the wick, it flows back to the evaporating section through the liquid-absorbing wick around the inner tube wall. Working in such a cycle, the heat pipe can transmit heat over a long distance in a small cross-sectional area without external force.

Contents of the invention

In order to overcome the shortcomings of the existing flue gas waste heat utilization equipment with small heat transfer coefficient and large heat exchange equipment, the utility model designs a combined heat pipe flue gas condensation economizer. The energy-saving device uses the principle of heat pipe to fully improve the heat transfer coefficient. At the same time, the heat exchange area in the evaporation box and the condensation box can be combined to optimize the heat exchange effect.

The technical solution adopted by the utility model to solve the technical problem is: the energy-saving equipment includes four parts: an evaporation box, a condensation box, a connecting pipe, and a condensate collecting and discharging device. The tube is a finned tube; the material is copper, stainless steel, carbon steel; the inside of the condensation box is a serpentine coil, the tube is a finned tube, and the material is copper, stainless steel, carbon steel; The sheet tubes are connected and divided into ascending pipes and descending pipes; the condensate collection and discharge device is set at the lower part of the evaporation box, which mainly collects and discharges the condensed water in the evaporation box, and the material is ordinary carbon steel; the serpentine coil in the evaporation box and the condensation box The inner serpentine coils are arranged correspondingly, connected by the corresponding ascending pipes and descending pipes, the inside of the pipes is vacuumed, and the working fluid of the heat pipes is flushed to form independent loop heat pipes. Its working characteristics: the flue gas enters the evaporator box, flows outside the tube, and the tube is the working medium of the heat pipe; the cooling water or cooling air enters the condensing box, flows outside the tube, and the tube is the working medium of the heat pipe; The working medium in the tube is heated, the temperature of the flue gas is lowered, the water vapor in the flue gas condenses to form condensed water, which is collected and discharged by the condensate collection device, and the working medium in the heat pipe in the finned tube in the evaporation box absorbs heat and evaporates to form steam, which enters the condensate through the rising pipe The finned tube in the box transfers heat to the cooling water or cooling air through the tube wall, heats the cooling water or the cooling air, and the steam in the tube exothermicly condenses to form a liquid working medium, which flows back to the evaporation box from the downcomer; the heated Cooling water or cooling air can be utilized. The flue gas has both sensible heat release and latent heat release of water vapor in the equipment, which improves the utilization efficiency of the waste heat of the flue gas.

The beneficial effects of the utility model are: the boiler flue gas enters the evaporation box of the energy-saving equipment, scours a group of serpentine coils in the evaporation box, the temperature of the flue gas is reduced, the sensible heat is recovered, and at the same time, the water vapor in the flue gas is condensed, and the latent heat is recovered. Recycling; effectively improving the boiler waste heat recovery efficiency; as the flue gas temperature gradually decreases after entering the evaporator, the heat transfer efficiency of the front coil and the rear coil changes. To achieve the uniformity of heat transfer of different heat pipe groups: due to the different boiler loads, when the heat transfer capacity changes, the optimization of heat transfer can be achieved by adding or subtracting heat pipe groups; In the case of low volume, the heat exchange area is greatly reduced, which reduces the volume of heat exchange and energy-saving equipment. At the same time, since the evaporation box is arranged in the flue, it is arranged separately from the condensation box, which is conducive to the convenient arrangement of equipment in the boiler room.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Fig. 1 is the overall layout of the utility model.

Figure 2 is a schematic diagram of the connecting pipes between the evaporating box and the condensing box.

Fig. 3 is a schematic diagram of connection of a single heat pipe group.

In the figure, 1 condensing box, 2 evaporating box, 3 connecting pipe, 4 condensate collection and discharging device, 5 evaporating box serpentine tube, 6 evaporating box serpentine tube fin, 7 condensing box serpentine tube, 8 condensing box serpentine tube fins.

In Fig. 1, the evaporating box 2 is lower than the condensing box 1, and the evaporating box 2 and the condensing box 1 are arranged separately. The serpentine tube 5 in the evaporating box 2 is the evaporation section of the heat pipe, and the serpentine tube 7 in the condensing box 1 is the condensation of the heat pipe. section, connecting pipe 3 connects different finned heat pipe groups. The boiler flue gas enters the evaporation box 2, the temperature of the flue gas decreases, the water vapor in the flue gas condenses, and the condensate is collected and discharged by the condensate collecting and discharging device 4.

In Fig. 2, there are different serpentine tube groups in the evaporation box 2 and the condensing box 1, and the serpentine tube groups are connected by connecting pipes 3 to form loop heat pipe groups.

Fig. 3 is a schematic diagram of the connection of a single heat pipe group. The connecting pipe 3 connects the serpentine pipe 5 in the evaporation box 2 and the serpentine pipe 7 in the condensation box 1 to form a loop heat pipe.

Claims (4)

1. combined type heat pipe flue gas condensing energy-saving appliance comprises evaporation tank, cooling cylinder, tube connector, condensate liquid collection tapping equipment four parts, and it is characterized in that: evaporation tank is interior to be the serpentine coil group, manages to be finned tube; Material is copper, stainless steel, carbon steel; In the cooling cylinder is the serpentine coil group, manages to be that finned tube, material are copper, stainless steel, carbon steel; Tube connector couples together the finned tube in evaporation tank and the cooling cylinder, is divided into tedge and down-comer; Condensate liquid is collected tapping equipment and is arranged on the evaporation tank bottom, main condensate water of collecting in the discharging evaporation tank, and material is an ordinary carbon steel.

2. combined type heat pipe flue gas condensing energy-saving appliance according to claim 1, it is characterized in that: the coiled pipe group is connected by tedge is corresponding with down-comer with the interior coiled pipe group of cooling cylinder in the evaporation tank, can make up according to the needs of heat exchange amount, change heat exchange area, thereby change the heat exchange amount.

3. combined type heat pipe flue gas condensing energy-saving appliance according to claim 1, it is characterized in that: evaporation tank, cooling cylinder tank material are carbon steel, the tube sheet material is copper, carbon steel, stainless steel.

4. combined type heat pipe flue gas condensing energy-saving appliance according to claim 1, it is characterized in that: the combination of evaporation tank and cooling cylinder can change placement location, and cooling cylinder can vertically up and down be placed with evaporation tank, also can setover.

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