GB2498950A

GB2498950A - Boiler system comprising a waste oil burner

Info

Publication number: GB2498950A
Application number: GB1201620.0A
Authority: GB
Inventors: Trevor Sedley Pimlott
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-01-31
Filing date: 2012-01-31
Publication date: 2013-08-07
Also published as: GB201201620D0

Abstract

A boiler system 2 comprises a waste oil burner 4, a combustion chamber 6, a boiler inner 8 and outer 10, at least one elongate duct 68, and a flue 72. The side wall 60 of the combustion chamber and the side wall 62 of the boiler inner define a first cavity 64 in fluid connection with the combustion chamber. The side walls of the boiler inner and the boiler outer define a second cavity 66 water jacket , through which water is circulated. Each elongate duct is arranged to pass through the second cavity, where each duct is in fluid connection with the first cavity. The flue is provided in fluid connection with each elongate duct, and the flue includes an exhaust 74 in fluid connection with the exterior. In use, when waste oil combusts in the waste oil burner, the heated gases given off during combustion move along a flow path defined between the combustion chamber and the flue, and in so doing facilitate the heating of the water. In a further aspect a boiler system is disclosed, where a boiler comprises a pot burner 14 adapted to burn waste fuel with a density range of 0.81 0.94 kg/litre.

Description

5

10 - 1 -

WASTE OIL BOILER SYSTEM

Field of the Invention

15

The invention concerns boiler systems, specifically waste oil boiler systems for heating water.

Background

20

It is not unusual in the case of a private or shared residence or small hotel or the like, for there to be a swimming pool, Jacuzzi or similar facility present. Such a facility often takes a hot water supply from the hot water system of its parent building. Swimming pools, and in particular outdoor swimming pools, are very energy inefficient, which is to say that a lot of 25 energy is used to keep the pool at a desirable temperature. Problems can develop when such a high demand site is added to a conventional heating system, the original purpose of which was to cater for a low demand water heating system, geared towards the provision for domestic needs, such as a system comprising a boiler running from conventional fuel oil or fuel gas. Heating the pool in this way can be very expensive, and can place an 30 intolerable demand on the system itself, which may lead to the entire system wearing out prematurely and/or breaking down. There is a therefore a need for a separate system to be provided, which provides a low cost means of providing hot water to a high demand site such a pool.

2

It is amongst the aims of the inventive to present a solution to the problems above. Summary of the invention

5 In a first broad, independent aspect, the invention comprises a boiler system, said system comprising a waste oil burner, a combustion chamber, said chamber having a top end and a bottom end and at least one side wall, said wall comprising a least a portion of heat conductive material, said bottom end being in fluid connection with the burner, a boiler inner, comprising at least one side wall, said wall comprising a least a portion of heat 10 conductive material, the side wall of the combustion chamber and the side wall of the boiler inner defining a first cavity, wherein said first cavity is in fluid connection with the combustion chamber, a boiler outer, comprising at least one side wall, wherein the side wall of the boiler inner and the side wall of the boiler outer define a second cavity, through which water is circulated, and at least one elongate duct, wherein the elongate duct is so 15 arranged to pass through the second cavity, and the elongate duct is in fluid connection with the first cavity, and a flue, in fluid connection with the elongate duct, said flue comprising an exhaust in fluid connection with the exterior, wherein the fluid connections between the above elements collectively comprise a flow path, wherein when waste oil combusts in the waste oil burner, the heated fumes given off during combustion move 20 along the said flow path, and in so doing are brought into proximity of the circulating water, thereby facilitating the heating of the water through the walls of the combustion chamber, the boiler inner and the boiler outer.

The burning of waste oil provides a means of producing low cost heat energy, and is 25 particularly appropriate for the heating of a high demand item such as a swimming pool. Burning of oil which might otherwise be disposed of or require processing or refinement before it can be used for other applications also provides efficiency and cost savings; also, by promoting the use of such waste, it provides an unexpected environmental advantage.

30 The flow path as defined provides several points of heat exchange between the heated fumes (or air /fume mixture) and the water in the boiler, namely at the top of the combustion chamber, the side(s) of the boiler inner, via the surface of the duct or ducts which pass through the second cavity or "water jacket". Such a flow path thereby facilitates the effective transfer of heat.

3

Preferably, the boiler further comprises a plurality of ducts, said ducts being radially spaced around the central vertical axis of the combustion chamber, with all of said ducts being situated in between the boiler inner and the boiler outer.

5 The provision of a plurality of ducts allows for the more effective and extensive exchange of heat.

Preferably, the boiler further comprising a condenser, said condenser being located immediately adjacent the flue.

10

The condenser provides a fourth area of heat exchange, which again increases the effectiveness and extent of heat exchange.

Preferably, the combustion chamber is completely open ended at the top end and at the 15 bottom end.

The complete openness allows for the fuel to combust before heat is exchanged through the boiler inner. The air movement from the fan keeps the fumes circulating around the flow path and ensures that the fumes mix with air, whilst denser particles which cannot be 20 made to evaporate by the furnace, remain in the pan, as ash.

Preferably, the combustion chamber, the boiler inner and the boiler outer are all circular cylindrical in shape, and both the boiler inner and the boiler outer have a top end and a closure, each of said closures completely blocking its respective top end.

25 The use of circular cylindrical body shapes for these three components assists equal distribution of the air fume mix to each of the ducts.

This feature also provides that there are no edges and corners for fumes to get caught in, or for sediment, either from fumes or from the circulation of water, to be deposited.

Preferably, the burner is a forced draft burner.

30 The use of a forced draft burner has the unexpected advantage of increasing the control the user has over the circulation of the air / fume mix for optimum burning performance.

4

Preferably, the boiler further comprises a casement, the said casement having an upper section and a lower section, wherein the upper section surrounds the side of the boiler outer and comprises a layer of insulation, and the lower section surrounds the waste oil burner, and has no such insulation layer.

5

The provision of an insulated upper section, and a non insulated lower section, assists in the cooling of the area around the burner, whilst ensuring that a minimum of heat is lost from the upper section, where heat exchange is taking place.

10 Preferably, the boiler further comprises at least one channel, said channel running from its first end, at the exterior of the boiler to its second end at the combustion chamber of the boiler, and wherein the second end comprises a mouth, said mouth being configured so as to drip feed waste oil onto the burner.

15 The drip feeding apparatus described enables the user to exert control over the amount of oil fed into the boiler, and thereby to control the amount of heat which it outputs at a given period. Further, by cutting the oil off, it is possible to starve the burner, and so turn the system off.

20 Preferably, the burner comprises a releasably attachable fire pan, and a hatch, through which the fire pan may be removed from the boiler system.

A releasably attachable fire pan allows for remote fuelling and cleaning.

25 In a second broad, independent aspect, the invention comprises a boiler system comprising a boiler, the boiler comprising a pot burner, said pot burner being adapted to burn waste fuel of a density of between 0.81 - 0.94 kg / litre.

As discussed above, the burning of waste fuel provides a useful, low cost and unexpectedly 30 environmentally sound means of powering a high output water boiler.

The invention also comprises a boiler system, substantially as described herein, with reference to and as illustrated by any combination of the text and/or drawings.

5

Brief Description of the Drawings

The invention will now be described in detail, with reference to the drawings, of which:

5 Figure 1 is a cross-sectional side view of a first boiler system of the invention,

Figure 2 is a cross-sectional side view of a second boiler system of the invention, and

Figures 3, 3a and 3b are perspective side views of components of a boiler system of the 10 invention,

Detailed description of the preferred embodiments

At Figure 1, there is a boiler system 2. The boiler system 2 comprises in its essential parts 15 a waste oil burner 4, a combustion chamber 6, a boiler inner 8, a boiler outer 10 and a flue 12. These essential elements are all encased in boiler system casement 13. Casement 13 is divided into upper part 20 and lower part 22. The casement 13 has, as a base for supporting the rest of the boiler system 2, a bottom flange 36 and on its top, a top flange 38, capped by a water-proof weather cover 40. The flanges are in preferred embodiments 20 made of welded metal. The other components of the boiler system 2 can be made of metal, alloys, plastics and / or any combination of natural and /or synthetic materials deemed appropriate by the skilled man.

The waste oil burner 4 is typically a pot burner 14. The pot burner comprises a fire pan 16 25 and a holder 18 for the fire pan 16. The fire pan 16 and holder 18 are encased in the lower part 22 of casement 13. The burner 4 is embedded in the casement's lower part 22, being separated from combustion chamber 6 by aperture 24, said aperture 24 providing the site for furnace 26. The burner 4 is, in the embodiment of figure 1 a forced draft burner, although other types of pot burner may successfully be used. The furnace 26 of the burner 30 4 comprises an oil feed 42, said oil feed 42 comprising a channel 44 with a mouth 46

through which, in the use oil may be dripped fed. The oil feed 42 is attached to a pump 48 which regulates the feeding, in use, of oil into the furnace 26. A portion of the wall 50 of the furnace 26 comprises the location of a fan assembly 52, which provides a draught for the furnace 26. Both the fan assembly 52 and the oil feed 42 may be controlled by the

6

user. The fire pan 16 is detachable and removable from the boiler system 2 via releasable locking means 54 - this facilitates cleaning, because the solid part of the combusted fuel comprising ash and soot will tend accumulate in the fire pan 16, and will need to be removed. The fire pan 16 can be removed from the boiler system 2 via a hatch (not 5 shown). The fan assembly 52 also operates to ensure that the fumes is well mixed with air, and that they mix is directed up the combustion chamber 6, which militates against the leaking of fumes from the boiler.

The upper casement 20 comprises a metal outer 28 and an inner layer of insulation 30. 10 The upper casement 20 and lower casement 22 are separated by a flange 32 which serves to keep the insulation in place. The lower casement 22 does not feature an insulation layer, comprising only its own metal outer 34.

The furnace 26 is connected to the combustion chamber 6, with the said combustion 15 chamber 6 having an open bottom end 56 and a top end 58 which in preferred embodiments is fully open but may also comprise a grille or similarly penetrable area. The combustion chamber 6 is in preferred embodiments a metal cylinder which therefore has a continuous wall 60. In this embodiment, combustion chamber 6, boiler inner 8 and boiler outer 10 all have such walls, but in common with both the boiler inner 8 and the boiler 20 outer 10, it may have multiple sides in other embodiments.

Both the top end 58 and the wall 60 of the combustion chamber 6 are surrounded by boiler inner 8, boiler inner 8 comprises a wall 62 spaced from combustion chamber wall 60, the space between the said two walls comprising a cavity 64.

25

Boiler inner 8 and boiler outer 10 define a second cavity or "water jacket" 66 between them, with one or more elongate ducts 68 running through said water jacket 66. In preferred embodiments a plurality of ducts 68 run longitudinally along the water jacket cavity 70 defined by boiler inner 8 and boiler outer 10.

30

In use when the furnace 22 is ignited using diesel fuel or another ignition substance, oil subsequently poured into the fire pan 16 combusts and hot fumes rise up along the combustion chamber 6, with heavier components of the fuel remaining in the pan 16 as ash. The remaining fumes exit the top end 58 of the combustion chamber 6 and flow

down along cavity 64. They subsequently pass through ducts 68. into flue assembly 72 and subsequently out through chimney 74 to the exterior. The flow path of the fumes exposes water 76 to the heat of the fumes three times in preferred embodiments; a first time via boiler inner walls 62 and a second time via ducts 68. In preferred embodiments 5 the boiler system 2 further comprises a condenser 78 running adjacent to flue assembly 72, which facilitates a third pass of air/fume mix adjacent to the water 76.

Water 76 is introduced to the system via return 80. It passes through condenser 78,

exiting condenser 78 and passing along longitudinal pipe 82, which runs through the 10 insulation 30 layer of the boiler system 2. From there it enters water jacket 66, circulating round water jacket 66 until it exits through exit pipe 84.

The embodiment of figure 2 lacks a condenser, having instead a straightforward entry pipe TOO and exit pipe 102 to water jacket 66.

15

Figures 3 - 3b show circular cylindrical embodiments of combustion chamber 6, boiler inner 8 and boiler outer 10. Although not necessarily to scale, it can clearly be seen that the three elements comprise cylinders wherein one can fit into the other.

20 The waste oil boiler system 2 may be adapted to work in either a vented heating system or an unvented heating system, with minimal adaptation.

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Claims

1. A boiler system, said system comprising;

5 a waste oil burner,

a combustion chamber, said chamber having a top end and a bottom end and at least one side wall, said wall comprising a least a portion of heat conductive material, said bottom end being in fluid connection with the burner,

10

a boiler inner, comprising at least one side wall, said wall comprising a least a portion of heat conductive material, the side wall of the combustion chamber and the side wall of the boiler inner defining a first cavity, wherein said first cavity is in fluid connection with the combustion chamber,

15

a boiler outer, comprising at least one side wall, wherein the side wall of the boiler inner and the side wall of the boiler outer define a second cavity, through which water is circulated, and at least one elongate duct, wherein the elongate duct is so arranged to pass through the second cavity, and the elongate duct is in fluid connection with the first 20 cavity,

and a flue, in fluid connection with the elongate duct, said flue comprising an exhaust in fluid connection with the exterior,

25 wherein the fluid connections between the above elements collectively comprise a flow path,

wherein when waste oil combusts in the waste oil burner, the heated fumes given off during combustion move along the said flow path, and in so doing are brought into 30 proximity of the circulating water, thereby facilitating the heating of the water through the walls of the combustion chamber, the boiler inner and the boiler outer.

2. A boiler system according to claim 1, wherein the boiler further comprises a plurality of ducts, said ducts being radially spaced around the central vertical axis of the

9

combustion chamber, with all of said ducts being situated in between the boiler inner and the boiler outer.

3. A boiler system according to either claim 1 or claim 2, the said boiler further 5 comprising a condenser, said condenser being located immediately adjacent the flue.

4. A boiler system according to any of the preceding claims, wherein the combustion chamber is completely open ended at the top end and at the bottom end.

10 5. A boiler system according to any of the preceding claims, wherein the combustion chamber, the boiler inner and the boiler outer are all circular cylindrical in shape, and both the boiler inner and the boiler outer have a top end and a closure, each of said closures completely blocking its respective top end.

6. A boiler system according to any of the preceding claims, wherein the burner is a 15 forced draft burner.

7. A boiler system according to any of the preceding claims, wherein the boiler further comprises a casement, the said casement having an upper section and a lower section, wherein the upper section surrounds the side of the boiler outer and comprises a layer of insulation, and the lower section surrounds the waste oil burner, and has no such insulation

20 layer.

8. A boiler system according to any of the preceding claims, further comprising at least one channel, said channel running from its first end, at the exterior of the boiler, to its second end at the combustion chamber of the boiler, and wherein the second end

25 comprises a mouth, said mouth being configured to so as to drip feed waste oil onto the burner.

9. A boiler system according to any of the preceding claims, wherein the burner comprises a releasably attachable fire pan, and a hatch, through which the fire pan may be

30 removed from the boiler system.

10. A boiler system comprising a boiler, the boiler comprising a pot burner, said pot burner being adapted to burn waste fuel of a density of between 0.81 - 0.94 kg / litre.

10

11. A boiler system, substantially as described herein, with reference to and as illustrated by any combination of the text and/or drawings.