WO2012021921A1 - Converting heat from industrial emissions to usable energy - Google Patents

Abstract

An arrangement for converting heat from high temperature industrial emissions to mechanical and/or electrical energy including a heat sink to which high temperature industrial emissions are directed from their source in the industrial process there towards, the heat sink supported and in thermal communication with a thermal energy absorbing medium configured to direct absorbed heat from the heat sink to a focal point such that when the high temperature industrial emission make contact with the heat sink heat is distributable out through the supporting thermal energy absorption medium to the focal point.

Description

CONVERTING HEAT FROM INDUSTRIAL EMISSIONS TO USABLE ENERGY

TECHNOLOGICAL FIELD This invention relates to an arrangement for utilising the heat from high temperature industrial emissions to mechanical and/or electrical energy. More specifically it relates to a better use or at least a recovery of the waste heat which is generated in various industrial and processing plants.

BACKGROUND ART DISCUSSION It is well recognised that a considerable quantity of heat energy is generated as a by-product, in the form of high temperature industrial emissions in many chemical and industrial processes such as gas and coal fired power stations as well as various kinds of blast furnaces used in metallurgy and so forth.

For the most part this by-product of the high temperature industrial emission is often filtered and then in some embodiments exposed into a series of steps to reduce the temperature down to a working level, wherein high temperature industrial emissions pass through various cooling chambers where water is sprayed onto the fast moving confined gases thereby withdrawing energy from the emissions creating a vapour-water mixture to which at a later stage the vapour is fed to act in various steam operations or alternatively discharged out through a chimney or other kinds of column stacks.

Hence as it can be seen for the most part considerable costs have been employed to create the necessary high temperatures in the original industrial process to which in itself presents its own by-product of a high temperature commodity, which rather than being utilised is in fact de-energised through the input of further energy and resources, such as the spraying in of fluids to make the vapour-water mixture rather than any practical means of harvesting the benefit and utilisation of this high temperature associated with the industrial emission.

As introduced above while lower level temperature is recovered for use of some of the industrial emissions, the point remains that the most beneficial or high level heat is discarded rather than being recovered in any practical reusable form.

Therefore there clearly remains a need within processing plants and other places where heat is being generated as a by-product to wherein such heat can be utilised or in a sense recovered as a source of reusable energy whether it be in the form of mechanical or electrical energy.

SUMMARY OF THE INVENTION

Accordingly in one form of the invention there is provided an arrangement for converting heat from high temperature industrial emissions to mechanical and/or electrical energy, said arrangement including: a heat sink device to which high temperature industrial emissions are directed from their source in the industrial process there towards, said heat sink device supported or in thermal communication with a thermal energy absorbing medium, said thermal energy absorbing medium configured to direct absorbed heat from said heat sink to a focal point, such that when the high temperature industrial emission make contact with the heat sink device heat is then be distributed out through the supporting thermal energy absorption medium supporting to then be conducted to the focal point.

In preference there are a plurality of focal points such that when the high temperature industrial emission make contact with the heat sink device heat is then be distributed out through the supporting thermal energy absorption medium supporting to then be conducted to the plurality of focal points.

In preference the high temperature industrial emissions are directed from their source in the industrial process towards a longitudinal chamber wherein said chamber supports there within a metal column acting as a heat sink to which the high temperature industrial emissions would pass internally there through making contact with internal configuration of the column.

In preference the longitudinal chamber is refractory lined.

In preference the metal column is surrounded by the thermal energy absorbing medium packed up against the confines of the longitudinal chamber such that the heat of the high temperature industrial emissions conducts out of the internal configuration of the column into the thermal energy absorbing medium to the or each focal point.

In preference at the or each focal point an electric machine converts thermal energy into electrical and/or mechanical energy.

In preference the electric machine is a Stirling heat engine wherein the Stirling cycle converts thermal energy into electrical energy.

In preference the column is cylindrical in configuration with internal radial blades that radiate outwards towards the edge to the column. Advantageously for the first time it is now possible to more readily utilise or in fact recover the energy that is wasted during high temperature industrial emissions, which as introduced above for the most part either were completely discharged or reduced significantly to use in much lower level temperature operations. Advantageously with this arrangement it is possible for the first time to utilise the energy associated with these high temperatures and convert them conveniently into mechanical and/or electrical energy.

The column that includes its radial blades presents an initial primary heat sink, exposing a wide service area to come in contact with the vast flowing gaseous mixture that is the high temperature industrial emission.

As the person skilled in the art will appreciate using the first law of

thermodynamic principles the heat is absorbed upon the column and is then distributed through the thermal energy absorbing medium where it is then again through the use of thermodynamics directed towards focal points within side the main housing.

It is at each of these focal points that heat is able to be concentrated and rather than simply discharging this heat it is utilised with the unique Stirling heat engine wherein the Stirling cycle is able to convert this thermal energy into electrical energy.

Advantageously not only are we reducing the effects of industrial emission and cleanly recovering the energy associated with the extreme or high temperatures of the emission brought about by the industrial process which they are generated from, we are utilising or recovering this energy to economically, safely and conveniently convert to a new form of electrical energy which can be used by the processing plant itself or rediverted into the applicable energy grid as a means of income for the plant.

Hence while significant energy is used in creating the necessary high temperatures for various chemical and industrial processes that take place in plants and factories, for the first time now the by-product of such processes in the form of high temperature industrial emissions can now see the heat from this by-product recovered and utilised beneficially to create its own form of electrical energy. In preference the thermal energy-absorbing medium configured to support the column inside the main housing of the arrangement is made substantially of a graphite material.

In preference this graphite material is segregated into two forms wherein the material immediately surrounding the column and radiating out towards the periphery of the longitudinal chamber enclosing the column would be of a powdered form wherein the graphite material which would be in close proximity to a refractory lined longitudinal chamber would be made from sintered graphite.

In preference the column that includes the internal radiating blades or baffles is made of copper.

In preference the column is a modulated unit of a substantially cylindrical configuration wherein sectional pieces of cylindrically shaped columns each containing the respective baffles can be joined end upon end to alter the length of the column. Advantageously by altering the length of the column means that there is the ability of controlling the temperature drop of the industrial emissions as they pass through the arrangement.

As introduced above in certain plants after the processing has been completed and emissions are released these emissions often have the high temperatures removed to utilise such emissions at lower temperatures.

Advantageously this arrangement still allows to actually control the recovery of the heat from the industrial emissions.

Therefore the ability still remains within this arrangement to utilise downstream use of the gaseous emission in other plant processes as required. Advantageously however rather than using previously available processes which simply function to remove the heat from the emissions to get them at working temperatures, in this embodiment it has been able to remove the heat that utilise this removal of heat in the creation of electrical and/or mechanical energy.

In preference the column could also include a series of collars about the circumferential outer edge of the column adapted to assist in joining together respective modular pieces of the column and to act as heat concentrators.

Advantageously these external collars that run around the peripheral circumferential edge of the column could also act as heat concentrators and therefore can be symmetrically placed inside the supporting structure of the graphite material inside the main housing to again assist the thermodynamic processes of the exchange of heat through the column out onto the graphite material as the conductive absorption of the heat through the material heads towards the focal points to then be utilised inside the Stirling heat engine to convert this thermal energy into electrical energy.

In preference the longitudinal refractory lined chamber along its inner sides includes a series of cavities.

In preference these cavities are sealable such that if not required and the amount cavities opened would be dependent on the amount of focal points designed into the system in order to concentrate the heat out from the high temperature industrial emissions to absorb and move towards said focal points to operate the respective Stirling heat engines.

An advantage of such an arrangement is that if one of the Stirling heat engines becomes inoperable or requires maintenance or needs to be shut down for particular reasons, the actual arrangement itself need not be isolated in any way. Advantageously by being able to simply close off the cavity one is then able to withdraw the Stirling heat engine from the arrangement for it to be appropriately repaired or reviewed for maintenance.

The point to be made is that the high temperature industrial emissions are allowed to continue to make their way through the arrangement despite the fact that certain amounts of cavities have been closed and the connected Stirling heat engines have been removed from the arrangement, for example as introduced above for repair or maintenance review.

This ability to be able to isolate the Stirling heat engines which are responsible for the most part in converting the thermal energy into electrical or mechanical energy means that the upstream plant processing which created this high temperature industrial emissions can continue on their operations.

As the arrangement provided for in this invention does not need isolation when repairs and maintenance are required to its moving and wearable parts, means that there is no interruption to the plant or factory's main purpose production.

The very unique streamlined arrangement of the cylindrical column again offers no hindrance or interruption to the flow of these industrial emissions and therefore avoids any unnecessary interruption, effect or influence upon the industrial processes that created these emissions in the first place. As the person skilled in the art will appreciate when one is talking about the creation of high temperature industrial emissions they are talking about significant chemical or industrial processes.

Once these operations commence the ability to shut them down is particularly costly, troublesome and sometimes inappropriate and therefore it would not be advisable to use any type of recovery operation to try and convert the heat from a high temperature industrial emissions if such arrangements had any ability to effect the processes that were actually creating these emissions. Advantageously as introduced above this arrangement does not interfere in any way with the plant processing that has created the high temperature industrial emissions.

In order now to gain an appreciation of the invention a series of preferred embodiments will be provided for with the assistance of the following

illustrations and accompanying text.

However these preferred embodiments presented with the assistance of the illustrations and text should be considered as not defining the invention as the general scope of the invention has already been presented herewith. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of the arrangement for converting heat from high temperature industrial emissions to mechanical and/or electrical energy utilising a Stirling heat engine.

Figure 2 is a similar representation to figure 1 however it is shown as a cross- sectional representation.

Figures 3(a), 3(b), 3(c), 3(d) and 3(e) show various representative views of the cylindrical column which is supported inside the longitudinal chamber packable in amongst the thermal energy absorption medium of the graphite material.

Figures 4(a) and 4(b) are perspective views of further embodiments of the invention.

Referring to the drawings now in greater detail where there is provided an arrangement (10) which would be designed into a processing plant of which as part of its chemical or industrial processes produces high temperature industrial emissions as a by-product. The arrangement (10) would be placed in line with the directed stream of the high temperature industrial emissions so that it is able to enter the upstream of the main housing block (12) or longitudinal chamber, the emissions are shown generally as (11), and makes its way through the arrangement (10) to be discharged down shown generally as (13).

Nonetheless what makes this arrangement work is the fact that the high temperature industrial emissions interact with the surface area exposed by the primary heat sink of the cylindrical copper column (16) wherein this heat then distributes its way through the powdered graphite material (19) and then on through the sintered graphite material (18) as it continues to conduct its way to the focal points shown generally as (20), best seen in figure 2.

The focal points (20) include a cavity which therein are connected or tapped thereon to is the Stirling heat engine (22) which is utilising the concentrated thermal heat which has been created inside the main housing block (12) as the emissions pass through the column (16) wherein this heat then distributes its way through the powdered graphite material (19) and then on through the sintered graphite material (18) as it continues to conduct its way to the focal point (20).

This concentration of heat upon the focal point (20) as it passes its way through the primary heat sink of the copper column (16) and through the graphite material (18), (19) has the Stirling engine (22) utilising thermodynamic principles of the Stirling cycle converting the thermal energy into electrical energy.

In the representations shown in figures 1 and 2, in order to understand the invention just the one Stirling heat engine (22) has been included and described.

Nonetheless cavities (30) could be located anywhere along the refractory lined housing of the main block (12) depending on just how much energy needs to be concentrated at the respective focal points (20) to generate the necessary heat which can be utilised by the Stirling heat engine to convert this created thermal energy into electrical energy.

Figures 3(a) through to 3(e) show what the cylindrical column (16) in sectional interconnecting pieces. Sectional or modulated cylindrical pieces (27) can be joined end to end to create the one single length of the copper column (16).

Collars (28) join these sectional pieces (27) or in some instances may be incorporated into single lengths of cylindrical tubes of copper as a means of being able to concentrate the heat which has been absorbed onto the internal blades or baffles (26) of the column (16) as the emissions shown generally as (15) in figure 3b make their way through to contact all the available surface area of the column (16) exposed to such emissions.

As the person skilled in the art will appreciate as the high temperature industrial emissions make their way through the passage of the column (16) and interact with the internal blades or baffles (26) of the column (16), heat is taken from the emission as the copper column (16) acts as a primary heat sink to then distribute this heat either in its concentrated form upon the collars (28) circling the circumferential peripheral edge of the column (16) or just on generally conductively onto the graphite powdered material (18), (19) that encapsulates or surrounds the column (16) inside the main housing block (12) of the arrangement (10).

Figures 4(a) and 4(b) simply present the embodiment of which was addressed generally above wherein a selected amount of cavities (30) can be designed into the main housing block (12). Decisions can be made as to whether all or some of these cavities will in fact provide for a focal point to be then in communication with a Stirling heat engine. The ability of being able to isolate or these cavities (30) through the use of slot (32) and gate (34), means that if during operation a particular Stirling heat engine needs to be removed from the system for repair or maintenance this can be done without shutting down the entire arrangement.

Selected cavities (30) can be isolated through the use of the gate (34) and slot (32) and once the cavity has been closed or tapped off the engine can then be removed to be worked upon.

Advantageously however there is no interruption to the high temperature industrial emissions that continue to run through the waste heat converter. This means that upstream plant processes do not have to be stopped to

accommodate the maintenance that needs to be carried out upon the waste heat recuperation system.

Claims

1. An arrangement for converting heat from high temperature industrial emissions to mechanical and/or electrical energy, said arrangement including: a heat sink to which high temperature industrial emissions are directed from their source in an industrial process there towards, said heat sink supported and in thermal communication with a thermal energy absorbing medium, said thermal energy absorbing medium configured to direct absorbed heat from said heat sink to a focal point, such that when the high temperature industrial emission make contact with the heat sink heat is distributable out through the supporting thermal energy absorption medium to the focal point.

2. The arrangement of claim 1 wherein there are a plurality of focal points such that when the high temperature industrial emission make contact with the heat sink heat is distributable out through the supporting thermal energy absorption medium to the plurality of focal points.

3. The arrangement of claim 1 or 2 wherein the high temperature industrial emissions are directed from the source in the industrial process towards a longitudinal chamber wherein said chamber supports there within a metal column acting as the heat sink to which the high temperature industrial emissions would pass internally there through said metal column.

4. The arrangement of claim 3 wherein the longitudinal chamber is refractory lined.

5. The arrangement of claim 3 or 4 wherein the metal column is surrounded by the thermal energy absorbing medium packed up against the confines of inner walls of the longitudinal chamber such that the heat of the high

temperature industrial emissions conducts out of the metal column into the thermal energy absorbing medium to the or each focal point.

6. The arrangement of claim 5 wherein each focal point includes an electric machine adapted to convert thermal energy into electrical and/or mechanical energy.

7. The arrangement of claim 6 wherein the electric machine is a Stirling heat engine wherein the Stirling cycle converts thermal energy into electrical energy.

8. The arrangement of any one of claims 3 to 7 wherein the metal column is cylindrical in configuration with internal radial blades that radiate outwards towards the edge to the metal column.

9. The arrangement of any one of claims 5 to 8 wherein the thermal energy- absorbing medium configured to support the column inside the longitudinal chamber is made substantially of a graphite material.

10. The arrangement of claim 9 wherein the graphite material is segregated into a first section and second section, wherein the first section immediately surrounds the metal column would be of a powdered form wherein the second section of the graphite material which would be in closer proximity to internal walls of the refractory lined longitudinal chamber would be made from sintered graphite.

11. The arrangement of any one of claims 3 to 10 wherein the metal column is configured from modulated units of a substantially cylindrical configuration wherein sectional pieces of cylindrically shaped columns each containing the respective baffles can be joined end upon end to alter the length of the metal column.

12. The arrangement of claim 11 wherein the metal column further includes a series of collars about the circumferential outer edge of the column adapted to assist in joining together respective modular units of the column and to act as heat concentrators.

13. The arrangement of claim 11 wherein the longitudinal refractory lined chamber along its sides includes a series of cavities sealable at each of the focal points such that if a focal point is not required said cavity maybe sealed off dependent on the amount of focal points designed into the arrangement to operate the respective Stirling heat engines during a particular period of operation.