JPS6121336B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot air heater that performs hot air heating with good thermal efficiency and recovers exhaust heat as humidifying steam into the heating air.

Conventionally, energy-saving methods for recovering exhaust heat from hot air heaters have involved either using a heat exchanger to exchange heat between the exhaust gas and air and using it directly for heating with a separate blower, or using the main system duct Methods of preheating the heating air by forcing waste heat recovery air into the combustion chamber or by connecting a duct to the suction side of the heating fan, or of preheating the combustion air are known. However, with the method of preheating the combustion air, the amount of combustion air is relatively small, so much of the recovered heat cannot be expected to be used effectively, and it also leads to an increase in the size of the burner blower and the capacity of the burner motor. However, preheating air for heating using an exhaust heat recovery heat exchanger is common, as the initial cost and running cost increase due to increased power consumption, which is offset by the recovery effect, so it is not very promising. Since heat is exchanged between gas and air, it requires a large heat transfer area, is large and complicated, and also takes into consideration the airtight structure and prevention of dew point corrosion, making it quite expensive. In addition, a separate blower and associated control device are required, and even if an additional blower is not installed,
It is necessary to increase the capacity of the heating blower to compensate for the pressure loss of the heat exchanger, which increases both the initial cost and running cost, and increases the time it takes to recover the cost.
Furthermore, although humidification is universally necessary in hot air heating, it is necessary to assemble a separate device.

The present invention effectively recovers the static cross heat that is originally emitted from the chimney as exhaust gas, increasing the thermal efficiency of the entire device, and furthermore, the exhaust heat is recovered as humidifying steam into the heating air, thereby saving energy. At the same time, it is possible to prevent steam from entering the heater after the heater is stopped, improving the durability of the heater, and preventing rust from forming on the inside of the hot air duct due to condensation. It is an object of the present invention to provide a hot air heater with an exhaust heat recovery type humidifier that can increase the durability of the equipment.

For this reason, the configuration of the present invention includes a hot air heater main body, an exhaust heat recovery type humidifier main body provided separately from the hot air heater main body, and a water supply device that supplies water to the humidifier main body. a chimney connected to the humidifier body; a warm air duct connected to the heater body; The main body of the hot air heater includes an outer shell to which the hot air duct is connected, a combustion chamber provided inside the outer shell, and a combustion chamber provided inside the outer shell. and an indirect contact type heat exchanger which is provided with an indirect contact type heat exchanger that uses the hot gas from the combustion chamber as a heat source to heat the heating air and convert it into hot air. an exterior casing having an exhaust gas inlet pipe communicating with the chimney and connected to an exhaust gas outlet pipe of the heat exchanger at a side thereof so as to introduce exhaust gas from the heat exchanger; and an interior of the exterior casing. an internal casing for evaporation, the bottom of which is connected to the water supply pipe from the water supply device, and the top and sides of which are closed; The apparatus is characterized in that it includes a steam extraction pipe, and a steam connection pipe in which a lower end opening of the steam extraction pipe is communicated with the outer shell of the hot air heater main body.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is the main body of the hot air heater, 2 is the main body of an exhaust heat recovery type humidifier provided separately from the main body 1 of the heater, and 3 is a water supply device that supplies water to the main body 2 of the humidifier. , 4 is a chimney connected to the humidifier body 2, 5 is a warm air duct connected to the heater body 1, and 6 is a hot air duct connected to the heater body 1, and 6 is a hot air duct that causes the heater body 1 to suck heating air from the heater body 1. A heating blower for supplying hot air to the hot air duct 5; 7 a connecting pipe connecting the water inlet of the water supply device 3 and a water pipe; 8 a water supply pipe supplying water from the water supply device 3 to the humidifier main body 2; 9 is a solenoid valve for water supply control provided in the middle of the connecting pipe 7, and 10 is a humitestat for controlling the solenoid valve 9.

The warm air heater main body 1 includes an outer shell 11 to which the warm air duct 5 is connected, a combustion chamber 12 provided inside the outer shell 11, and a combustion chamber in which fuel is supplied to the combustion chamber 12. an indirect contact heat exchanger 14 which is provided inside the outer shell 11 and uses the hot gas from the combustion chamber 12 as a heat source to heat heating air and turn it into hot air; A return duct 16 connected to the air suction port 15 of No. 11 is provided.

The exhaust heat recovery type humidifier main body 2 also has an upper part that communicates with the chimney 4 and a side part that is connected to the heat exchanger 14, as shown in enlarged views in FIGS. 2 and 3. An exterior casing 19 having an exhaust gas introduction pipe 18 connected to the exhaust gas outlet pipe 17 of the heat exchanger 14 so as to introduce exhaust gas, and an exterior casing 19 provided inside the exterior casing 19 and connected to the water supply pipe 8 at the bottom thereof. An interior casing 21 for steam generation that has a water supply inlet 20 and is closed at the top and sides, and a steam extraction pipe 22 that is erected inside the interior casing 21 and is open at both upper and lower ends. , the lower end opening 23 which is the steam outlet of this steam outlet pipe 22 is connected to the outer shell 1 of the heater main body 1.
It is equipped with a steam connecting pipe 24 and the like which are communicated with 1.

In the hot air heater with an exhaust heat recovery type humidifier configured in this way, water is supplied to the water supply device 3 by connecting the connecting pipe 7 to the water pipe. This water supply device 3 supplies water through the water supply pipe 8 into the internal casing 21 of the exhaust heat recovery type humidifier main body 2 and maintains a constant water surface height. Combustion chamber 1 in hot air heater main body 1
The high-temperature combustion gas generated in step 2 exchanges heat with heating air in the heat exchanger 14, drops in temperature to around 300°C, exits the heat exchanger 14, and is introduced into the exterior casing 19 of the humidifier body 2. be done. Then, the water in the interior casing 21 is evaporated and turned into low-temperature exhaust gas that is released from the chimney 4 into the atmosphere. The steam evaporated within the interior casing 21 increases in steam pressure within the casing 21, enters the pipe 22 from the upper end opening of the steam extraction pipe 22, descends, and flows through the steam connecting pipe 24 to the heater main body 1. It is pushed into the outer shell 11 as humidifying steam by steam pressure and mixed with hot air for heating,
The hot air is sent through the hot air duct 5 to the room to be heated. Here, while combustion continues in the combustion chamber 12, the surface temperatures of the combustion chamber 12 and the heat exchanger 14 are sufficiently high, the air temperature is also rising, and the air is sent indoors without condensation. Therefore, the various devices inside the hot air heater main body 1 are not contaminated. Further, even if combustion stops, the heating blower 6 continues to rotate until the combustion chamber 12 and the heat exchanger 14 are sufficiently cooled, and the inside of the heater body 1 is maintained at a positive pressure. On the other hand, evaporation inside the interior casing 21 begins to decrease as soon as combustion stops, and the vapor pressure gradually decreases, causing the interior casing 21
The humid air inside stops flowing into the heater main body 1, and humidification is stopped. Then, when the temperatures of the combustion chamber 12 and the heat exchanger 14 are sufficiently cooled, the heating blower 6 is also stopped. At this time, the vapor pressure within the interior casing 21 has been sufficiently reduced, but some surface evaporation continues due to the residual heat of the water. However, since the steam outlet is the lower end opening 23 of the steam outlet pipe 22, the wet steam inside the interior casing 21 with residual heat stays at the ceiling inside the casing 21 and flows into the heater main body 1. Keep it to a minimum. Therefore, there is an effect of minimizing contamination due to dew condensation on the surfaces of the combustion chamber 12 and the heat exchanger 14, where the temperature has dropped. Also, depending on the steam pressure, the heater body 1
Since steam is forced into the interior or into the duct 5, there is no need for a humidifying blower or the like, and there is no need for a special control device associated with this, resulting in cost reduction, simple structure, and advantages in terms of maintenance. If the humidity in the room is too high, the humidity level 10
The solenoid valve 9 is closed, the water supply is restricted and the water level is lowered, and the amount of humidification is gradually reduced, and humidification is stopped when the water in the interior casing 21 has completely evaporated. Then, when the humidity in the room drops, water is supplied and humidification is resumed. Note that the temperature of the exhaust gas after heat exchange in the heat exchanger 14 is around 300°C, so even if there is no water in the interior casing 21, the humidifier main body 2 will not burn out due to dry firing.

As described above, the present invention provides a hot air heater body and an exhaust heat recovery type humidifier body separately, and guides the exhaust gas after heating air for heating in the heater body to the humidifier body. Since the thermal energy of the exhaust gas is recovered into the heating air as evaporation for humidification, the statcross heat that would normally be exhausted from the chimney can be used effectively, increasing the thermal efficiency of the entire device.
In addition, when using exhaust heat, compared to conventional heating air preheating that exchanges heat from gas to air, combustion exhaust gas → water →
Steam has a better heat transfer rate and can be made smaller and simpler to construct. In addition, a steam extraction pipe is installed upright in the interior casing which is the steam generation chamber of the humidifier body, and the lower end of the pipe is connected to the outer shell of the heater body as a steam extraction outlet, and normally during heating, the pressure is positive. Since the steam is forced into the heater body or into the hot air duct by steam pressure, there is no need to install a special blower or controller. Moreover, compared to the conventional pan type that is built into the heater body, installing it inside the flue simplifies the structure of the heater body.
In addition, the air passages and gas passages are not narrowed, and there is no increase in internal resistance, so not only is there no increase in the power of the burner blower or heating blower, but maintenance and inspection of the humidifier body and heater body are easy. Become. Also, the flue gas temperature is normally 300
℃, so there is no risk of burnout even if the humidifier is heated dry, but since the humidifier is installed separately from the heater, there is a risk of damage or water leakage. However, it can be detected quickly, and water leakage accidents do not reach the combustion chamber or heat exchanger of the heater itself. In particular, in the body of the exhaust heat recovery type humidifier, the humidified steam is taken out at the lower end of the steam take-off pipe, and there is a sufficient closed space above the heated water in the inner casing, so that the amount of water retained is kept at the minimum required amount. Since the overall heat capacity can be reduced, the startup is quick, and even if there is natural evaporation due to residual heat of the heated water after the heating water has stopped, convection occurs in the upper space and water condenses on the inner surface of the interior casing, rapidly condensing water. The steam pressure is lowered and returns to the heated water as water droplets, and the temperature of the humid air inside the steam extraction pipe is kept warm by the residual heat of the heated water, so there is no downdraft within the pipe, and therefore the heater The release of humid air to the outer shell after the engine stops is stopped very quickly, and there is no dew condensation on the inner surface of the hot air duct, which is effective in fully achieving the intended purpose of preventing rust from forming.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional front view showing an embodiment of the present invention, Fig. 2 is an enlarged sectional front view of the exhaust heat recovery type humidifier body shown in Fig. 1, and Fig. 3 is a section line taken along the cutting line in Fig. 2. A-A
FIG. 1... Warm air heater body, 2... Exhaust heat recovery humidifier body, 3... Water supply device, 4... Chimney, 5... Warm air duct, 6... Heater blower, 11... Outer shell, 1
2... Combustion chamber, 14... Heat exchanger, 19... Exterior casing, 21... Interior casing, 22...
Steam extraction pipe, 24...steam connecting pipe.

Claims (1)

[Claims] 1. A hot air heater main body, an exhaust heat recovery type humidifier main body provided separately from the hot air heater main body, a water supply device that supplies water to this humidifier main body, and a water supply device connected to the humidifier main body. a hot air duct connected to the heater body, and a heating blower that causes the heater body to draw heating air and transfer the hot air from the heater body to the hot air duct. ,
The warm air heater main body includes an outer shell to which the warm air duct is connected, a combustion chamber provided inside the outer shell, and a combustion chamber provided inside the outer shell to receive heat from the combustion chamber. It is equipped with an indirect contact type heat exchanger that heats heating air using gas as a heat source and converts it into hot air. an exterior casing having an exhaust gas inlet pipe connected to an exhaust gas outlet pipe of the heat exchanger so as to introduce exhaust gas from the heat exchanger into the exterior casing; an internal casing for evaporation that communicates with the water supply pipe from the evaporator and is closed at the top and sides; a steam extraction pipe that stands inside the internal casing and is open at both upper and lower ends; A hot air heater with an exhaust heat recovery type humidifier, comprising a steam connecting pipe in which a lower end opening of a steam extraction pipe is communicated with an outer shell of the hot air heater main body.