CN111076414A

CN111076414A - Combustion heating equipment

Info

Publication number: CN111076414A
Application number: CN201911266715.0A
Authority: CN
Inventors: 孙爱霞
Original assignee: Beijing Xinli Machinery Co Ltd
Current assignee: Beijing Xinli Machinery Co Ltd
Priority date: 2019-12-11
Filing date: 2019-12-11
Publication date: 2020-04-28

Abstract

A combustion heating apparatus. The domestic boiler preheater includes a flue box, and the flue box includes: a combustion gas inlet that receives hot combustion gases from the boiler; and a combustion air inlet that receives air for combustion in the boiler. The preheater comprises a condenser comprising a mains cold water inlet and a mains water outlet, the mains being arranged such that mains water flows through the condenser before being supplied to the boiler combustion chamber. The condenser comprises a central heating water return port arranged such that the central heating water flows through the condenser before being supplied to the boiler combustion chamber, and a central heating water outlet. The condenser includes a connection enabling the condenser to be connected from a source of preheated fluid to a preheated fluid supply line, the preheated fluid including a fluid heated by heat from at least one of combustion gases and renewable energy sources.

Description

Combustion heating equipment

Technical Field

The present invention relates to a home boiler preheater used in a building to heat water for central heating and/or hot water supply.

It is desirable to be able to make heat transfer more efficient in a combustion process in a domestic boiler to reduce the amount of fuel used to achieve the desired feedwater heating. This applies both to central heating water supply and to hot water supply.

The present invention results from some work done to improve the efficiency of domestic boilers.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a combustion heating device, which may be a (domestic) boiler preheater, comprising a flue box comprising a combustion gas inlet for receiving hot combustion gases from a boiler and a combustion air inlet for receiving air. For combustion in the boiler, the preheater further comprises a condenser comprising a mains cold water inlet and a mains water outlet, the mains being arranged such that mains water flows through the condenser before being supplied to the boiler combustion chamber, the condenser further comprising central heating water. The return pipe and the central heating water flow outlet are arranged such that the central heating water flows through the condenser before being supplied to the boiler combustion chamber, the condenser further comprising a connection enabling the condenser to be connected from the preheating source to the preheating fluid supply conduit. A fluid, the preheated fluid comprising a fluid ionic gas heated by heat from the at least one combustion chamber and a renewable energy source, the condenser operable to transfer heat from the preheated fluid to at least one of mains cold water from a mains cold water inlet or central heating water from a central heating water circuit to preheat the mains or central heating water prior to entering the boiler combustion chamber.

Preferably, a combustion gas heat exchanger is provided for transferring heat from the combustion gas flowing through the combustion gas inlet to the combustion air flowing through the combustion air inlet, such that the combustion air is preheated before entering the boiler.

Preferably, the combustion gas heat exchanger is operable to heat the preheated fluid before the preheated fluid enters the condenser.

The combustion gas heat exchanger may comprise a portion of a flue box or may comprise a portion of a separate flue tube. Any of the foregoing may be incorporated into the combustion heating apparatus at the time of manufacture or at the time of installation of the apparatus, or may be retrofittable (into existing installed apparatus).

Preferably the combustion gas heat exchanger comprises at least one fluid filled glow stick, heat being transferred from the combustion gas to the fluid (which may be vaporised) and heat being transferred from the (vaporised) fluid to the inlet for combustion. Air, which may include subsequently condensed fluid. The fluid in the glow stick may transfer heat from the exhaust gas to the intake air by convection.

The term "heater bar" is intended to be understood in a broad sense and includes parts or components intended to allow heat transfer from the exhaust gas to the intake air. In case the hot bar contains a fluid (which may be a gas or a liquid) for heat transfer, the fluid is contained in a sealed system or a sealed space, which is at least partly defined by the inner surface of the hot bar.

Where a combustion gas heat exchanger is provided at the flue gas box, preferably a set of parallel hot bars is provided, although these need not be parallel and may be in different relative orientations.

Where the combustion gas heat exchanger is provided in a separate flue, preferably a set of hot bars spaced along the longitudinal axis of the flue are provided.

The heating rods may comprise substantially solid metal rods, such as copper rods, whereby heat is conducted by these rods.

Preferably the condenser comprises a set of tubes, some of which are connected between the mains cold water inlet and the mains water outlet so that mains water passes along the tubes, and some of which are connected between the central heating water return and the central heating water. The condenser also includes a heat exchange coil arranged to transfer heat from the preheated fluid to the water in the tubes to pass the central heating water along the tubes.

The renewable energy source may directly heat the preheated fluid and may thus comprise, for example, a water-heated solar panel or a ground-source heat pump.

According to a second aspect of the present invention there is provided a boiler, which may be a domestic boiler, comprising a preheater according to the first aspect of the present invention.

According to a third aspect of the present invention there is provided a flue assembly which may be a domestic boiler flue assembly comprising a preheater according to the first aspect of the present invention.

According to another aspect of the invention, there is provided a flue box comprising the preheater of the first aspect of the invention.

Although particular reference is made to combustion heating apparatus for use in domestic environments or environments, the invention is equally applicable in industrial environments such as industrial heating applications.

It should be appreciated that one aspect of the present invention may be viewed as involving the use of heat in the exhaust gas produced by the combustion process to preheat the hot water used in the combustion process, the central hot water and the incoming air.

Other aspects of the invention may include any combination of the features or limitations mentioned herein.

Drawings

Fig. 1 is a perspective view of a preheater for a home boiler according to the present invention.

Fig. 2 is a sectional view taken along line a-a of the preheater of fig. 1.

Fig. 3 is a side view of another domestic boiler preheater according to the present invention.

FIG. 4 is a side view of a flue tube for a preheater of a domestic boiler according to the present invention.

Figure 5 is a perspective cross-sectional view of the flue tube of figure 1.

Figure 6 is an end view of the flue tube of figure 5.

Detailed Description

Reference is first made to fig. 1 to 4. Referring to fig. 1 and 2, the domestic boiler preheater 1 is a self-contained unit, which in this example is arranged to be installed in a domestic boiler (not shown) and comprises a part.

The preheater 1 comprises an upper flue box 3, which upper flue box 3 is substantially hollow and is provided with internal combustion gas outlet channels and internal inlet air channels. The combustion gas outlet channel extends between a combustion gas inlet 5, which receives, in use, combustion gases from the boiler, and a flue outlet/inlet 7, which flue outlet/inlet 7 comprises, in this example, a standard 90 ° flue bend protruding from the top of the flue box 3. An inlet air passage extends between the flue outlet/inlet 5 and a combustion air outlet 9, the combustion air outlet 9 supplying, in use, combustion air to the boiler combustion chamber. The flue box 3 thus diverts and separates combustion gases and intake air and enables standard flue components to be connected to the flue inlet/outlet 7.

In this example, the flue outlet/inlet 7 is a double-walled concentric flue, wherein hot combustion gases pass through the inner flue 7A in one direction and cold intake gases pass through the outer flue 7B in the opposite direction. Therefore, some of the heat in the combustion gas is transferred through the wall of the inner flues 7A to the cooler intake air drawn through the outer flues 7B.

The combustion gas heat exchanger 11 is provided in the form of an array of elongate heat bars 13 arranged in the path of the hot combustion gases from the boiler. In this example, the heat exchanger 11 is provided at the flue box 3, but it may also be provided, for example, inside a boiler combustion chamber. The heat exchanger 11 transfers heat from the combustion gases to the fluid within the hot bar 13, evaporates as the fluid absorbs heat from the combustion gases, and then condenses to transfer the absorbed heat to the inlet combustion air.

Thus, in this example, some of the heat from the combustion gases is transferred directly to the cooler combustion air through the flue itself, while some of the heat from the combustion gases is transferred to the cooler combustion air through the intermediate fluid in the combustion chamber. And a hot bar 13. The preheater 1 also includes a condenser 15 mounted below the flue box 3. The condenser 15 comprises two primary

heat exchange coils

17, 19 which extend around an array of parallel water carrying tubes 20 within the condenser. Some of the water ducts 20 extend between a mains cold water inlet 21 and a mains cold water outlet 23, while others extend between a central heating water return inlet 25 and a central heating water outlet 27. In use, some of the tubes 20, and central hot water flows through other tubes 20.

The primary heat exchange coils 17, 19 carry a preheated fluid which transfers heat from the preheated fluid to the mains/central hot water in the tubes 20. This is used to preheat the main/central hot water prior to entering the combustion chamber of the boiler. Therefore, the boiler must use less fuel, even zero fuel, to transfer the necessary heat to the mains and the central hot water.

The preheated fluid carried by

coils

17, 19 may be preheated by any suitable heat source. An example of such a heat source is the heat in the combustion gases, which, as mentioned above, may be transferred to the preheated fluid through the combustion gas heat exchanger 11.

The preheated fluid may be preheated via a renewable energy source. In one example, the preheated fluid may be provided directly from a water heating solar panel or a ground source heat pump. The preheated fluid may be provided indirectly via an electric water heater driven by electricity from a renewable power source such as a photovoltaic panel or a wind generator.

A combination of sources may be used to preheat the preheated fluid. For example, the fluid may be heated first by a solar panel and then further by the combustion gas heat exchanger 11.

The preheater 1 is arranged as an integral part of a new boiler and may be accommodated within the boiler housing.

Suitable controls may be provided to control the flow of water and/or preheated fluid through the preheater and to control the start-up of the combustion chamber accordingly. If sufficient heat is contained in the preheated fluid, this may be sufficient to provide the necessary heat to the water, and in this case the controller will be operable to deactivate the combustion chamber.

Reference is additionally made to the figures. As shown in fig. 3, the other preheater 31 includes similar features as the preheater 1, with similar features given similar reference numerals.

The preheater 31 is arranged to be retro-fittable into the flue of an existing boiler, that is, the preheater 31 is arranged to be mountable on the boiler flue without the need to replace the boiler. Thus, it can be used to improve the efficiency of existing boilers.

In this example, the components of the preheater 31 are provided in a separate housing 33, the housing 33 being connected in a flue between a flue outlet 35 of a boiler 37 and a standard flue outlet 39 from the building. The separate housing 33 may be arranged to be wall-mounted or floor-mounted, or may be adapted to be mounted directly on the boiler 37 itself. The preheater 31 includes the same main water inlet and outlet as the main heater 1 and the flow and return of the centrally heated water is the same as the preheater 1, the internal flue, the combustion gas heat exchanger and the primary coil are similar.

Reference is additionally made to fig. 1 to 4. Referring to fig. 4 to 6, the home boiler flue tube 41 is of a concentric double-walled type, with combustion gases flowing in one direction through the inner flue tube 43 and cooler inlet combustion air flowing in the other direction through the outer flue tube 45. An array of elongated hot sticks 13 of the combustion gas heat exchanger 11 is disposed in the flue pipe 41 itself. Thus, a plurality of the glow sticks 13 are spaced apart along the longitudinal axis of the flue tube 41, each glow stick 13 extending transversely across the flue tube 41 from the inner tube 43 to the outer tube 45. Heat is transferred from the hot combustion gases. In the inner tube 43, as described above, the air is combusted toward the cooler inlet in the inner tube 43 as the fluid within each hot rod 13 vaporizes and subsequently condenses. As can be seen in fig. 1 and 2. Referring to fig. 5 and 6, each heating rod includes fins that facilitate the heat transfer process. As can also be seen in fig. 2. As shown in fig. 5, the heat bars may be arranged in different directions all extending across the exhaust space of the flue. In the case where the heater bar contains a fluid for effecting heat transfer (e.g., by convection), the heater bar itself provides an internally sealed volume in which the fluid is contained.

The flue pipe 41 thus comprises its own combustion gas heat exchanger 11, which combustion gas heat exchanger 11 may replace the combustion gas heat exchanger 11 arranged on the flue box 3 of the

preheater

1, 31 or be a complement thereof.

The flue tube 41 has been shown as a straight tube, but any other shape or configuration of flue tube is contemplated. Likewise, any number, orientation and spacing of heating rods 13 may be used as desired.

Also, the water carrying tube 20 and heat exchange coils 17, 19 are merely exemplary, and other configurations for heat transfer within the condenser may be used.

It should be understood that the heating rod may comprise a substantially solid metal rod, whereby heat is conducted through its thermal conductivity.

Claims

1. A combustion heating unit preheater comprising:

an assembly comprising at least one of a flue box, a flue tube and a combustion chamber, wherein the assembly further comprises a combustion chamber gas heat exchanger arranged to transfer heat from the combustion gas to the intake combustion air in use, the heat exchanger comprising an array of heating rods filled with a fluid or solid metal rod, in the case of fluid-filled rods, arranged to transfer heat from the gas into the fluid from which it is transferred to the intake combustion air.

2. The apparatus of claim 1, wherein the heating rod is arranged to extend transverse to the interior space of the flue tube with the heating rod disposed in the flue tube.

3. The apparatus of claim 1, wherein the heat bar comprises one or more heat exchange fins.

4. The apparatus of claim 2, wherein the heat bar comprises one or more heat exchange fins.

5. The apparatus of claim 1, comprising a plurality of spaced apart heat bars.

6. The apparatus of claim 5, wherein the hot bars are spaced apart in a longitudinal direction of the flue with the hot bars disposed in the flue.

7. The apparatus of claim 1, wherein the pre-heater is a module arranged to be connected to a flue at initial installation or commissioning of the apparatus, or as a retro-fittable module of the apparatus.

8. The apparatus of claim 1, for use with a boiler for heating liquid of at least one of a central heating system and a hot water supply system.

9. The apparatus of claim 1, which is a gas boiler preheater.

10. A combustion heating unit preheater comprising:

a flue box, comprising:

a combustion gas inlet that receives hot combustion gases from the boiler; and

a combustion air inlet that receives air for combustion in the boiler;

a condenser, comprising:

a power supply cold water inlet;

a tap water outlet, wherein the tap water cold water inlet and the tap water outlet are arranged such that tap water flows through the condenser before being supplied to the boiler combustion chamber.

Central heat supply backwater;

a central hot water outlet, wherein the central hot water return and the central hot water outlet are arranged such that central hot water flows through the condenser before being supplied to the boiler combustion chamber. And

a plurality of connections enabling the condenser to be connected from a source of preheated fluid to a preheated fluid supply conduit, wherein the preheated fluid comprises a fluid heated by heat from any one of combustion gases or renewable energy sources;

a combustion gas heat exchanger for transferring heat from the combustion gas flowing through the combustion gas inlet to the combustion air flowing through the combustion air inlet such that the combustion air is preheated before entering the boiler,

wherein said condenser transfers heat from said preheating fluid to at least one of mains cold water from said mains cold water inlet or central heating water returned from said central heating water to preheat the mains or central heating water chamber prior to combustion in said boiler, wherein the combustion gas heat exchanger comprises at least one fluid-filled heating rod, wherein heat is transferred from the combustion gas into the fluid, and wherein heat is transferred from the vaporizing fluid to the intake combustion air by subsequently condensing the fluid.