JPH10267204A - Liquid tube convection type combustion heating furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a problem requiring anticorrosion to cope therewith while improving heating effect by arranging liquid tubes of miscellaneous shapes on a flame forming surface of a planar flame type burner with the minimum dimension closer to the maximum dimension among the same horizontal sections. SOLUTION: A group 56A of upstream side liquid tubes has a plurality of liquid tubes 56 and one liquid tube 56X. Flame 28 formed by a multi-perforated planar fireproof block 73 of a planar flame type burner 2A is guided to an internal wall 54 to be built between the liquid tubes 56 with a circular horizontal cross section. Moreover, an oval liquid tube 56X is smaller in the ratio of the surface area to the internal capacity than the liquid tubes 56 with a circular horizontal sectional area while it is arranged to approach the multi-perforated planar fireproof block 73 so that the flame 28 hits the block before the combustion thereof is completed, a condition in which the combustion temperature does not rise so high. This eliminates a problem requiring anticorrosion to cope therewith, for example, overheating of a diluted liquid 22 in the oval liquid tube 56X. In addition, heating through the walls of the liquid tubes 56 improves heating effect.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid heating device such as a high-temperature regenerator in an absorption refrigerator (including a device called an absorption chiller / heater).

[0002]

2. Description of the Related Art For example, an absorption refrigerator having a structure shown in FIG. 3 is well known. In the figure, reference numeral 1 denotes a high-temperature regenerator that includes a combustion device 2 such as gas or kerosene, generates refrigerant vapor 24 by heating a dilute liquid 22 of an absorbing liquid, and concentrates it into an intermediate liquid 23;
3 is a low-temperature regenerator that heats and concentrates the intermediate liquid with the refrigerant vapor from the high-temperature regenerator to make it a concentrated liquid. 4 is a condenser that cools and condenses the refrigerant vapor from the low-temperature regenerator. 5 is a refrigerant sprayer. 5
An evaporator for spraying / dropping the refrigerant liquid from A to evaporate,
Reference numeral 6 denotes an absorber for absorbing the refrigerant vapor from the evaporator into the concentrated liquid from the low-temperature regenerator 3 to maintain the inside of the device at a low pressure. Reference numerals 7 and 8 denote low-temperature and high-temperature heat exchangers. The pipes 9 to 12 are connected by refrigerant pipes 13 to 16 to form a circulation cycle of the refrigerant and the absorbing liquid, and either cold water or hot water selectively extracted from the heat exchanger 17 provided inside the evaporator 5 is provided. , Can be circulated and supplied to a heat load (not shown).

[0003] P1 is an absorption liquid pump provided in the absorption liquid pipe 9 for supplying the dilute liquid from the absorber 6 to the high temperature regenerator 1. P2 is provided in the refrigerant pipe 16 and provided at the bottom of the evaporator 5. A refrigerant pump for spraying the accumulated refrigerant liquid from the refrigerant sprayer 5A installed on the upper portion onto the heat exchanger 17;
V2 and V2 are cooling / warming switching valves provided in the absorbent pipe 11 and the refrigerant pipe 14, and closed when cold water is taken out from the heat exchanger 17 and opened when hot water is taken out.

A cold / hot water pipe 18 circulates and supplies cold water or heated hot water cooled by the heat exchanger 17 to a heat load such as cooling / heating (not shown). A cold / hot water pump P3 is attached to the inlet side.

[0005] Also, 19 and 20 are coolers provided inside the condenser 4 and the absorber 6, which are connected by a cooling water pipe 21 having a cooling water pump P4, and a cooling tower (not shown) and the absorber 6 The cooling water is circulated between the cooling water and the condenser 4.

[0006] In the absorption chiller having the above configuration, during the cooling operation in which chilled water is taken out, an absorption refrigeration cycle is performed by circulating the refrigerant and the absorption liquid, so that the latent heat of evaporation of the refrigerant in the evaporator 5 causes the heat in the heat exchanger 17 to be removed. Water can be cooled and supplied to about 6 to 8 ° C., and during the heating operation in which hot water is taken out, the supply of the cooling water to the coolers 19 and 20 is stopped while the on-off valves V1 and V2 are closed. By switching to open, the high-temperature absorbing liquid and refrigerant vapor
1. The refrigerant flows into the absorber 6 and the evaporator 5 from the high-temperature regenerator 1 via the refrigerant pipes 13 and 14, and the hot water heated by the heat exchanger 17 by the latent heat of condensation of the refrigerant and the sensible heat of the absorbing liquid is supplied. .

Since the high-temperature regenerator 1 occupies a large part in both the weight and the volume of the absorption refrigerator, the miniaturization of the high-temperature regenerator 1 is indispensable in order to reduce the overall size of the absorption refrigerator. It is. Further, as an environmental problem in the high-temperature regenerator 1, a demand for lowering NOx during combustion has been increasing.

However, the conventional high-temperature regenerator 1 disclosed in JP-A-63-294467 and JP-A-6-221718 has a liquid tube type boiler structure as shown in FIG. It was difficult to reduce the size.

That is, the combustion device 2 in this case is a nozzle type burner that burns the mixed gas 27 of the fuel gas 25 and the air 26 in the combustion chamber 51 provided at the tip side of the nozzle 71. The flame 28 and the high-temperature combustion gas (not shown) are supplied to the inner wall 5 of a container 50 surrounding a combustion chamber 51 and a heating chamber 52 connected to the downstream side of the combustion chamber 51.
4 and a large number of liquid tubes 56 erected in the heating chamber 52 and then discharged from the exhaust port 53 as exhaust gas.

Then, the diluted liquid 22 of the absorbing liquid supplied from the absorber 6 flows into the container 50 from the absorbing liquid pipe 9, and the horizontal lower communication portion 57A, that is, the inner wall 54 and the outer wall 5
5, a horizontal upper communication portion 57B, that is, an upper clearance between the inner wall 54 and the outer wall 55, and a vertical communication portion 57C, that is, both sides between the inner wall 54 and the outer wall 55. It is stored in the gap and the inside of the plurality of liquid pipes 56 communicating with the horizontal communication portions 57A and 57B, and is heated by the flame 28 and the combustion gas while convection in the container, and is located above the horizontal upper communication portion 57B. The refrigerant vapor 24 evaporated into the gaseous phase portion 59 is discharged from the refrigerant pipe 13 and the refrigerant vapor 2
The intermediate liquid 23 having a high concentration due to evaporation of the liquid 4 flows out to the absorbing liquid pipe 10. In addition, since the refrigerant vapor 24 immediately after evaporation contains a droplet-like absorbing liquid component, the refrigerant vapor 24 is allowed to flow out to the refrigerant pipe 13 by bypassing the outflow path with the bypass plate 60. ing.

Therefore, in the high-temperature regenerator 1 having the above-described structure, since the combustion device 2 is a nozzle type burner, the flame 28
And the liquid tube 56 through which the dilute solution 22 flows is in direct contact with the flame 28, so that the dilute solution 22 is partially heated and crystallized. It is necessary to provide the combustion chamber 51 in front of the heating chamber 52 for reasons such as that the combustion chamber 51 is easily corroded, or the flame is cooled and unburned gas remains, and it is difficult to reduce the size. there were.

In Japanese Patent Application Laid-Open No. 63-294467, the combustion chamber 51 and the heating chamber 52 are formed in a folded shape, and the liquid pipe 56 is arranged on the folded side path.
There is disclosed a configuration in which a heat absorbing fin 56F is provided in the liquid pipe 56 located behind the path in order to improve heat absorption. In Japanese Patent Application Laid-Open No. Hei 6-221718, the liquid pipe 56 is connected to the heating chamber 52.
And a heat absorbing fin is provided on the rear side of the flat liquid tube 56, which is remarkable for miniaturization. Effect has not yet been achieved.

On the other hand, the gas-fired heating furnace is not provided with a combustion chamber 51 but provided with a flat combustion surface, etc. The loess tube-branch system has been introduced recently. In this furnace tubeless tube group system, the flame 28 and the combustion gas generated by the planar flame type burner 2A as shown in FIG. 4 are directly led to the heating chamber 52, and a combustion chamber is required. Not only dramatically reduces size,
It has also succeeded in reducing NOx.

That is, in the planar flame type burner 2A, the mixed gas 27 in which the fuel gas and the air containing the amount of oxygen necessary for combustion are mixed is supplied to the mixed gas chamber 72,
The flame 28 is designed to burn through the conducting hole 74 of the multi-hole planar refractory block 73 and to burn in a plane.
Is formed on the outer combustion surface 75, so that the combustion chamber 51 is not required, and the high-temperature regenerator 1 is significantly reduced in size.

The multi-hole planar refractory block 73 is formed mainly of a thick plate-like refractory material, for example, ceramic or metal fiber provided with a large number of fine conductive holes 74 as shown in the figure. . Reference numeral 76 denotes a small burner for ignition, and reference numeral 28a denotes a flame formed by the small burner for ignition.

[0016]

However, in a liquid tube convection type high temperature regenerator equipped with the above-mentioned planar flame type burner as a combustion device, a highly corrosive absorbent is heated to evaporate and separate the refrigerant. However, the temperature of the absorbing solution must not be too high (the temperature at which refrigerant vapor is generated in a high-temperature regenerator is about 160 ° C., and when it exceeds 200 ° C., the corrosiveness sharply increases). On the other hand, when the flame forming surface of the planar flame type burner is small, the heat load concentrates on the liquid pipe erected in front of the flame forming surface, and if it exceeds 200 ° C, a problem occurs in the corrosion resistance of the furnace material. In addition, there is a problem that the efficiency of heating the liquid inside through the pipe wall is low, and the overall heating efficiency is reduced in the liquid pipes provided upright other than in front of the burner. And these solutions have become issues. .

[0017]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the prior art, and has a large number of liquid pipes which communicate with upper and lower horizontal communicating portions to enable convection. A planar flame-type burner is installed horizontally facing a heating chamber that is erected away from each other, and the high-temperature combustion gas generated by this planar flame-type burner passes through the heating chamber, and mainly the liquid pipe wall. In a liquid tube convection-type combustion heating furnace configured to heat the liquid in the furnace via

A liquid tube having an oblong horizontal section is disposed with the long diameter portion of the tube wall facing the flame forming surface of the planar flame burner, and is provided on the side and back of the oval liquid tube. A liquid tube convection-type combustion heating furnace having a first configuration in which a horizontal cross section is circular or a liquid tube having a deformed shape whose minimum and maximum dimensions in the same horizontal cross section are close to each other;

In the liquid tube convection type combustion heating furnace of the first structure, a liquid of a second structure in which a plurality of elliptical liquid tubes are arranged along the flame forming surface of the planar flame burner. By providing a tube convection type combustion heating furnace, the above-mentioned problem of the prior art is solved.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Note that, in these figures, the same reference numerals are given to the portions having the same functions as those described in FIGS. 3 to 5 in order to facilitate understanding.

[First Embodiment] The first embodiment is shown in FIG.
In the figure, reference numeral 61 denotes a burner installation port, which has a width smaller than the width of the heating chamber 52 and a height equal to the height of the heating chamber 52 in front of the heating chamber 52. . The burner installation port 61 is provided with the above-described FIG.
The planar flame type burner 2A having the configuration described in (1) is installed.

The liquid tube 56 of the heating chamber 52 is
Are located upstream and downstream of the combustion promoting space 52A where no flame is provided, that is, the upstream liquid pipe group 56A located on the side of the multi-hole planar refractory block 73 forming the flame 28, and the exhaust port 53 side. It is erected separately from the downstream liquid tube group 56B.

The liquid tubes 56 of the upstream liquid tube group 56A include a plurality of liquid tubes 56 having a circular horizontal cross section and a single liquid tube 56X having an oblong horizontal cross section. The elliptical liquid tubes 56X are disposed with the long diameter portion of the tube wall facing the multi-hole planar refractory block 73 which is the flame forming surface of the planar flame type burner 2A, and have a plurality of liquids having a circular horizontal cross section. The tubes 56 are arranged in a zigzag manner on the side of the oval liquid tube 56X and on the back thereof.
The efficiency of heat exchange between the combustion gas passing through this portion and the diluted liquid 22 in the liquid pipe 56 is improved.

The liquid pipes 56 of the downstream liquid pipe group 56B are all liquid pipes having a circular horizontal cross section. Also in this case, the liquid pipes 56 are arranged in a staggered manner, and the combustion gas passing through this portion and the liquid pipe 56 The efficiency of heat exchange with the dilute solution 22 is improved.

In the high-temperature regenerator 1 having the above-described structure, the flame 28 formed by the multi-hole planar refractory block 73 of the planar flame type burner 2A is directed to the side of the inner wall 54 by the oval liquid tube 56X. Guided, a horizontal section on the side of the oval liquid tube 56X is formed between the circular liquid tubes 56.
Moreover, the oblong liquid tube 56X has a surface area to internal volume ratio smaller than that of the liquid tube 56 having a horizontal cross-sectional area, and collides before the flame 28 completes combustion, that is, in a state where the temperature has not risen so much. And the elliptical liquid pipe 56
The inconvenience that the diluted liquid 22 in X becomes overheated and the corrosion resistance becomes a problem is solved.

The inner wall 54 is formed by an elliptical liquid tube 56X.
And a flame 28 formed between the liquid tubes 56 having a horizontal cross section on the side of the oval liquid tube 56X.
As a result, the heating is performed through the pipe wall of the liquid pipe 56 that is not provided upright on the front surface of the multi-hole planar refractory block 73, and thus there is a feature that the heating efficiency is improved.

Further, the high-temperature combustion gas generated by the flame 28 is supplied to the upper and lower horizontal communicating portions 57A and 57B (FIG. 5).
The diluted liquid 22 in the vertical side communication part 57C, the diluted liquid 22 in the oval liquid pipe 56X of the upstream liquid pipe group 56A, and the diluted liquid 22 in the liquid pipe 56 having a circular horizontal cross section. to reduce the rapidly its temperature by releasing heat to, NO _X in the exhaust gas is significantly reduced.

[0028] Moreover, the combustion gas that has been cooled to a temperature which is effective in the NO _X reduction is so passes through the combustion promotion space 52A to the liquid pipe 56 is not erected even one, the temperature of the combustion gas in this portion It is difficult to decrease, and the combustion reaction proceeds when passing through, and the CO gas concentration in the waste gas also decreases.

[Second Embodiment] A second embodiment is shown in FIG.
It will be described based on. In this case, the high-temperature regenerator 1 is provided with two elliptical liquid tubes 56X facing the multi-hole planar refractory block 73 of the planar flame burner 2A.

In the high-temperature regenerator 1 having the above configuration, the same operation and effect as those of the high-temperature regenerator 1 having the first configuration can be obtained.

The elliptical liquid tube 56X may be a liquid tube having a rectangular horizontal section. Further, the liquid tubes 56 erected on the side and the back of the oval liquid tube 56X may be liquid tubes having a horizontal cross section of a triangle, a square, a pentagon, or the like.

[0032]

As described above, in the liquid tube convection type combustion heating furnace according to the present invention, since the liquid stored in the furnace does not locally become overheated, the high temperature regeneration of the absorption refrigerator is performed. It can be applied to a vessel, etc. to separate the refrigerant by evaporation.
The disadvantage that the corrosive absorbing solution is not overheated and therefore corrosion resistance becomes a problem is eliminated.

Further, the flame is guided in the lateral direction by the elliptical liquid pipe, and heating is also performed through the pipe wall of the liquid pipe erected other than in front of the burner, so that the heating efficiency is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a first embodiment in a cross section.

FIG. 2 is an explanatory diagram showing a second embodiment in a cross section.

FIG. 3 is an explanatory diagram of an absorption refrigerator.

FIG. 4 is an explanatory diagram of a heating device.

FIGS. 5A and 5B are explanatory views showing a conventional technique, wherein FIG. 5A is a longitudinal sectional view, FIG. 5B is a transverse sectional view, and FIG. 5C is a longitudinal sectional side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High temperature regenerator 2 Combustion device 2A Plane flame type burner 3 Low temperature regenerator 4 Condenser 5 Evaporator 6 Absorber 7 Low temperature heat exchanger 8 High temperature heat exchanger 9-12 Absorbent pipe 13-16 Refrigerant pipe 17 Heat exchange Apparatus 18 Cold / hot water pipe 19/20 Cooler 21 Cooling water pipe 22 Rare liquid 23 Intermediate liquid 24 Refrigerant vapor 25 Fuel gas 26 Air 27 Mixed gas 28 / 28a Flame 50 Container 51 Combustion chamber 52 Heating chamber 52A Combustion promoting space 53 Exhaust port 54 Inner wall 55 Outer wall 56 Liquid pipe 56A Upstream liquid pipe group 56B Downstream liquid pipe group 57A Horizontal lower communication section 57B Horizontal upper communication section 57C Vertical side communication section 59 Gas phase section 60 Detour plate 61 Burner installation port 71 Nozzle 72 Mixing Gas chamber 73 Multi-hole planar refractory block 74 Guide hole 75 Combustion surface 76 Small burner for ignition P1 Absorbent pump P2 Refrigerant pump 3 cold water pump P4 cooling water pump V1 · V2-off valve

Claims (2)

[Claims] 1. A planar flame-type burner is installed laterally facing a heating chamber in which a plurality of liquid pipes which communicate with each other and allow horizontal convection by forming upper and lower horizontal communication sections face each other. This is a liquid tube convection type combustion heating furnace configured so that the high temperature combustion gas generated by the planar flame type burner passes through the heating chamber and heats the liquid in the furnace mainly through the liquid tube wall. A liquid tube having an oblong horizontal section is arranged with the long diameter portion of the tube wall facing the flame forming surface of the planar flame burner,
Liquid tube convection combustion heating characterized by the fact that a horizontal cross section is circular on the side and back of the elliptical liquid tube, or a modified liquid tube whose minimum and maximum dimensions in the same horizontal cross section are close to each other. Furnace. 2. The liquid tube convection type combustion heating furnace according to claim 1, wherein a plurality of elliptical liquid tubes are arranged along the flame forming surface of the planar flame burner.