Abatement apparatus and method of abatement

Abstract

Abatement apparatus 1 comprises a treatment chamber 2 defined by a first porous wall 5 and has an effluent gas stream inlet 3. A second porous wall 7 surrounds the first porous wall and defines a seco

Description

Field The present invention relates to an abatement apparatus for treating an effluent gas stream from a manufacturing processing tool. The present invention also relates to a method of abatement of an effluent gas stream from a manufacturing processing tool. Background Abatement apparatus are known and are typically used for treating an effluent gas stream from a manufacturing processing tool used in, for example, the semiconductor or flat panel display manufacturing industry. During use of the manufacturing processing tool, residual perfluorinated compounds (PFCs) and other compounds may be present in the effluent gas stream pumped from the process tool. PFCs are difficult to remove from the effluent gas and their release into the environment is undesirable because they are known to have relatively high greenhouse activity. Typically, abatement apparatus use combustion to remove the PFCs and other compounds from the effluent gas stream. There is a desire to improve the efficiency of the abatement process, particularly there is a desire to reduce energy use during abatement. Thermal losses within the system are undesirable as the heating of the abatement apparatus housing can be dangerous, as well as making the apparatus more expensive to operate. The present invention aims to solve, at least in part, these and other problems associated with the prior art. Summary In an aspect, the present invention provides an abatement apparatus for treating an effluent gas stream from a manufacturing processing tool. The abatement apparatus comprises a treatment chamber at least partially defined by a first porous wall. The treatment chamber comprises an inlet configured to enable an effluent gas stream from the manufacturing processing tool to enter the treatment chamber. The abatement apparatus further comprises a second porous wall generally surrounding the first porous wall and defining therebetween a second chamber. The second chamber contains a relatively thermally conductive material. The second chamber is porous to allow gas flow therethrough. The abatement apparatus further comprises one or more heating elements configured to heat the relatively thermally conductive material. The abatement apparatus further comprises a third porous wall generally surrounding the second chamber and defining therebetween a third chamber. The third chamber contains a relatively thermally insulating material. The third chamber is porous to allow gas flow therethrough. The abatement apparatus further comprises a gas inlet. The apparatus is configured such that, in use, a gas flow is conveyed from the gas inlet through the third chamber and the second chamber to the treatment chamber where it reacts with the effluent gas stream. The manufacturing processing tool may be a tool used in, for example, the semiconductor or flat panel display manufacturing industry. The skilled person will appreciate that the abatement apparatus according to the present invention is not limited to abatement of gases from a particular manufacturing processing tool used in a specific industry. Rather, the abatement apparatus may be selected according to the composition and / or characteristics (e.g. temperature, flow rate) of the effluent gas stream. The composition and characteristics of the effluent gas stream may depend on the manufacturing processing tool to which the abatement apparatus is connected when in use. Furthermore, the composition and / or the characteristics of said effluent gas stream may depend on the specific processing step occurring in the manufacturing processing tool. Typically, the effluent gas stream may comprise constituent components that are toxic and / or damaging to the atmosphere because of their high greenhouse activity. For example, residual perfluorinated compounds (PFC’s) and other compounds may be present in the effluent gas stream and should be removed in the abatement apparatus. The treatment chamber may define the region of the abatement apparatus where the effluent gas stream may react with the gas flow to treat the effluent gas stream. The treatment chamber has an inlet that may be fluidly coupled to the processing tool. In use, the effluent gas stream may flow through the inlet into the treatment chamber. In some embodiments, the treatment chamber may comprise a plurality of inlets, wherein each inlet is fluidly coupled to the processing tool. The plurality of inlets may split the effluent stream as it enters the treatment chamber and provide improved dispersion. Alternatively, in some embodiments, each inlet may be fluidly coupled to a different processing tool, and configured to enable an effluent gas from said processing tool to enter the treatment chamber. The treatment chamber may further comprise an outlet through which gases may exit the treatment chamber following treatment of the effluent gas stream. The treatment chamber is at least partially defined by the first porous wall. The treatment chamber may be generally cylindrical, although the skilled person will appreciate that it is not limited to this shape. The inlet may be at a first end, and the outlet may be at a second end. The first porous wall may be a perforated wall, or a substantially regular openwork mesh. Preferably, the first porous wall may be a generally tubular wall. The first porous wall may enable gas to pass through during use of the abatement apparatus. The first porous wall may comprise a metallic material, for example, Inconel™ or Kanthal™. The material may be selected such that it can survive contact with the effluent stream without significant degradation. Preferably, the first porous wall may comprise a metallic sheet with a plurality of perforations therethrough. The second porous wall may be a perforated wall, or a substantially regular openwork mesh. Preferably, the second porous wall may be a generally tubular wall. The second porous wall may generally surround the first porous wall. The second porous wall may enable gas to pass through during use of the abatement apparatus. The second porous wall may comprise a metallic material, for example, a stainless steel alloy. This material may be selected such that it does not melt or degrade at the operating temperature of the abatement apparatus. Preferably, the second porous wall may comprise a metallic sheet with a plurality of perforations therethrough. Typically, the perforations through the first porous wall and / or the second porous wall may be generally circular. Preferably, the perforations may have a diameter of from about 0.5 mm to 2 mm, preferably about 1 mm. The size and density of the perforations may be selected according to the desired flow rate of gas when in use. The second chamber is defined between the first generally tubular wall and the second generally tubular wall. Preferably, the second chamber may be generally tubular. In other words, the second chamber may be an annular cylinder. Preferably, the second chamber may be coaxial with first chamber. The second chamber may generally surround the treatment chamber. Typically, the relatively thermally conductive material may be configured to allow the gas to flow through or across it during use of the abatement apparatus. When in use, the relatively thermally conductive material may be heated by the heating elements to elevated temperatures, preferably greater than about 500 °C. The relatively thermally conductive material may be configured to heat the gas as it flows through / past the relatively thermally conductive material. Then, the heated gas flow may enter the treatment chamber to react with the effluent gas stream. The relatively thermally conductive material may be selected such that it is substantially unreactive with the gas flow, even at operational temperatures. In abatement apparatus of the prior art, the gas flow would pass through the heater prior to entering the treatment chamber. Due to the relatively small surface area of the heater, little conductive heat transfer would occur between the heater and the gas. In contrast, the relatively thermally conductive material in the present invention may provide a relatively large surface area to allow for more efficient heat transfer to the gas flow. The second chamber may be substantially filled with the relatively conductive material. Preferably, at least 50% of the volume of the second chamber may be filled with the relatively conductive material, more preferably at least 75% of the volume of the second chamber, for example, at least 85% of the volume of the second chamber. By way of non-limiting example, the relatively thermally conductive material may be an opencelled porous solid, or a plurality of porous or non-porous particles. For the avoidance of doubt, the relatively thermally conductive material may be distinct and separate from the first porous wall, the heating element(s), and / or second porous wall. The relatively thermally conductive material may be a solid material. The relatively thermally conductive material may comprise a monolithic structure, or a plurality of particulates (i.e. particulate matter). The second chamber being porous may mean that it is configured to allow gas to flow therethrough and / or around and / or through the relatively conductive material(s) located therein. Preferably, the second chamber is optically opaque, whilst allowing a gas flow rate sufficient for treatment of the effluent gas flow in the treatment chamber. In other words, the second chamber may be arranged such that there is no linear path from the second porous wall to the first porous wall that is not blocked (i.e. intersected) by the relatively thermally conductive material. The one or more heating elements may comprise, for example, resistive heating elements and / or infra-red (IR) heating elements. Preferably, the one or more heating elements consist of resistive heating elements. The heating elements may be arranged proximate the relatively thermally conductive material, preferably in contact with at least a portion of the relatively thermally conductive material. In use, the heating element(s) may be configured to heat the relatively thermally conductive material. Preferably, the heating element(s) may be submerged within the relatively thermally conductive material. In other words, preferably the heating element(s) may not be in contact with the first porous wall or the second porous wall. Preferably, the heating element(s) may be arranged between the first porous wall and the second porous wall. Preferably, in use, the effluent stream does not come into contact with the heating element(s). Such contact may result in contamination and / or corrosion of the heating element(s). The third porous wall may be a wall comprising perforations, or a substantially regular openwork mesh. Preferably, the third porous wall may be generally tubular wall. The third porous wall may generally surround the second porous wall. The third porous wall may enable gas to pass through during use of the abatement apparatus. The third porous wall may comprise a metallic material, for example, a stainless steel alloy. Preferably, the second porous wall may comprise a metallic sheet with a plurality of perforations therethrough. The size and density of the perforations may be selected according to the desired flow rate of gas when in use. The third chamber is defined between the second generally tubular wall and the third generally tubular wall. Preferably, the third chamber may be generally tubular. In other words, the third chamber may be an annular cylinder. Preferably, the third chamber may be coaxial with first chamber and the second chamber. Typically, the relatively thermally insulating material may be configured to allow the gas to flow through or across it during use of the abatement apparatus. The relatively thermally insulating material may be configured to enable gas flow, whilst reducing heat transfer through the third chamber. The relatively thermally insulating material may be selected such that it is unreactive with the gas flow, even at operational temperatures. The third chamber may be substantially filled with the relatively insulating material. Preferably, at least 50% of the volume of the third chamber may be filled with the relatively insulating material, more preferably at least 75% of the volume of the third chamber, for example, at least 85% of the volume of the third chamber. By way of non-limiting example, the relatively thermally insulating material may be an opencelled porous solid, or a plurality of porous or non-porous particles. For the avoidance of doubt, the thermally insulating material may be distinct and separate from the second porous wall, and / or third porous wall. The relatively thermally insulating material may be a solid material. The relatively thermally insulating material may comprise a monolithic structure, or a plurality of particulates. The third chamber being porous may mean that it is configured to allow gas to flow therethrough and / or around and / or through the relatively thermally insulating material located therein. Preferably, the third chamber is optically opaque, whilst allowing a gas flow rate sufficient for treatment of the effluent gas flow in the treatment chamber. In other words, the third chamber may be arranged such that there is no linear path from the third porous wall to the second porous wall that is not blocked (i.e. intersected) by the relatively thermally insulating material. In abatement apparatus of the prior art, the outer wall of the treatment chamber housing may reach temperatures of about 200 °C. This is both inefficient and potentially dangerous. The running costs of such abatement apparatus are also increased by such thermal losses. Upon investigation, the present inventors have established that the heat is transferred to the outer wall of the treatment chamber housing from heating elements configured to heat the gas as it flows into the treatment chamber. Advantageously, the present inventors have established that by providing the third chamber containing relatively thermally insulating material, heat transfer outwards in the direction of a treatment chamber housing may be significantly reduced. The present invention may not require additional insulation sleeves and / or cooling devices arranged about the treatment chamber housing. The gas inlet, in use, may be coupled to a gas source. The gas source may be configured to supply a thermally conductive gas to react with the effluent gas stream in the treatment chamber. The gas inlet may be arranged such that the flow path of gas from the gas inlet to the treatment chamber passes through the third porous wall into the second chamber, then through and / or across the relatively thermally insulating material, then through the second porous wall into the first chamber, then through and / or across the relatively thermally conductive material to increase the temperature of the gas, then through the first porous wall and into the treatment chamber, where it reacts with the effluent gas stream. In the present invention, the abatement apparatus may be configured such that the effluent gas does not enter the second chamber or the third chamber. This may be achieved by ensuring a positive gas flow into the treatment chamber to react with the effluent gas flow. Additionally, or alternatively, the outlet of the treatment chamber may be connected to a partially evacuated duct to maintain the treatment chamber at a lower pressure than the second chamber or third chamber. Advantageously, the present invention provides a more efficient abatement apparatus. The present invention also provides an abatement apparatus having reduced thermal losses through the outer wall defining the treatment chamber housing. Typically, the abatement apparatus further comprises an outer wall generally surrounding the third porous wall, and defining therebetween a plenum. The outer wall may be the wall defining the treatment chamber housing. The plenum generally surrounds the third porous wall. The gas inlet may be arranged such that gas flow therethrough is conveyed into the plenum prior to entering the third chamber. Accordingly, the plenum may disperse the gas flow such that it enters the third chamber at multiple locations. Advantageously, this may improve the dispersion of the gas flow through the third and second chambers, increasing efficiency. Typically, the relatively thermally conductive material may have a thermal conductivity of at least ten times the thermal conductivity of the relatively thermally insulating material. Preferably, the relatively thermally conductive material may have a thermal conductivity of at least one hundred times the thermal conductivity of the relatively thermally insulating material. More preferably, the relatively thermally conductive material may have a thermal conductivity of at least one thousand times the thermal conductivity of the relatively thermally insulating material. Advantageously, this may improve the heat transfer to the gas as it flows across and / or through the relatively conductive material in the second chamber, whilst reducing the heat transfer through the relatively insulating material in the third chamber. Typically, the relatively thermally conductive material has a thermal conductivity greater than about 100 Wm-1K-1. Typically, the relatively thermally conductive material contained in the second chamber may be a relatively thermally conductive particulate matter. Preferably, the relatively thermally conductive material contained in the second chamber may be a packed bed of relatively thermally conductive particulate matter. Advantageously, the relatively thermally conductive particulate matter may provide increased surface area for heat transfer between the relatively thermally conductive particulate matter and the gas flow passing through the particulate matter. The abatement apparatus may be supplied with the relatively thermally conductive particulate matter packed within the second chamber. In some embodiments, the second chamber may be openable to enable replacement of the relatively thermally conductive particulate matter. Preferably, the relatively thermally conductive particulate matter may have substantially the same particle size (i.e. maximum particle diameter). Preferably, the relatively thermally conductive particulate matter may have a particle size of from about 1 mm to about 20 mm, more preferably from about 1 mm to about 5 mm, most preferably from about 2 mm to about 4 mm. Preferably, the relatively thermally conductive particulate matter comprises silicon particles. Typically, the relatively thermally conductive particulate matter is the same (i.e. material and / or particle geometry) throughout the second chamber. Typically, the relatively thermally insulating material may have a thermal conductivity less than about 10 Wm'1K'1, preferably less than about 1 Wm'1K'1, more preferably less than about 0.1 Witt1 KT Typically, the relatively thermally insulating material contained in the third chamber may be a relatively thermally insulating particulate matter. Preferably, the relatively thermally insulating material contained in the third chamber may be a packed bed of relatively thermally insulating particulate matter. Advantageously, the relatively thermally insulating particulate matter may enable gas flow, whilst reducing heat transfer through the third chamber. Thereby, heat transfer to the treatment chamber housing may be reduced. As the gas flow enters the third chamber, there may be a pressure drop due to the particulate matter. This may aid dispersion of the gas. The abatement apparatus may be supplied with the relatively thermally insulating particulate matter packed within the third chamber. In some embodiments, the third chamber may be openable to enable replacement of the relatively thermally insulating particulate matter. Typically, the relatively thermally insulating particulate matter comprises pumice and / or micafil vermiculite. Typically, the relatively thermally insulating particulate matter is the same (i.e. material and / or particle geometry) throughout the third chamber. Typically, the one or more heating elements may be resistive heating elements and / or infrared heating elements. Preferably, there may be from about 1 to about 24 heating elements. Typically, the one or more heating elements are configured to heat the relatively thermally conductive material to a temperature from about 500 °C to about 1200 °C. Preferably, the one or more heating elements are configured to heat the relatively thermally conductive material to a temperature from about 700 °C to about 1000 °C. More preferably, the one or more heating elements are configured to heat the relatively thermally conductive material to a temperature from about 900 °C to about 1000 °C. Most preferably, the one or more heating elements are configured to heat the relatively thermally conductive material to a temperature from about 950 °C to about 980 °C. Advantageously, this may ensure that the gas flow into the treatment chamber is hot enough to react with the effluent gas. Typically, the gas flow conveyed through the gas inlet comprises compressed dry air and / or nitrogen. Preferably, the gas flow is substantially free from fossil fuels (e.g. methane). Advantageously, this may be more environmentally friendly than prior art abatement solutions, as fossil fuels are not required in the reaction with the effluent gas flow. In a further aspect, the present invention provides a method of abatement of an effluent gas stream from a manufacturing process tool. The method comprises the steps of: a) providing an abatement apparatus according to any embodiment of the preceding aspect; b) operating the one or more heating elements to heat the relatively thermally conductive material within the second chamber; c) conveying a gas flow from the gas inlet to the treatment chamber through the third chamber and the second chamber; d) abating the effluent gas stream with the gas flow in the treatment chamber; and e) conveying the abated gas stream through an outlet of the treatment chamber. Advantageously, the method of present invention provides a more efficient method of operation of an abatement apparatus. Specifically, the gas flow is heated more efficiently as it flows through the second chamber across and / or through the relatively thermally conductive material. Furthermore, the method of the present invention also provides an abatement apparatus having reduced thermal losses through the treatment chamber housing, due to the insulating effect of the relatively thermally insulating material contained within the third chamber. Further features and advantages may be as described in any embodiment of the preceding aspect. Typically, in step (b) the heating elements may heat the relatively thermally conductive material to a temperature from about 500 °C to about 1200 °C, preferably from about 700 °C to about 1000 °C, more preferably from about 900 °C to about 1000 °C, most preferably from about 950 °C to about 980 °C. Advantageously, this may allow the gas flow passing through the second chamber, and therefore through and / or across the relatively thermally conductive material, to be heated prior to entering the treatment chamber. This may enable effective abatement of the effluent gas stream in the treatment chamber. Typically, the gas flow may comprise compressed dry air and / or nitrogen. Advantageously, the method of the present invention may enable abatement of the effluent gas stream without requiring fossil fuel (e.g. methane) to provide the heat to abate the process gases. For the avoidance of doubt, all aspects and embodiments described herein may be combined mutatis mutandis. It is also to be understood that this invention is not limited to the embodiments and aspects set forth in the following detailed description or illustrated in the drawings. The invention may be implemented in various other embodiments and is capable of being implemented in alternative ways not expressly disclosed herein. Brief Description of Figures Preferred features of the present invention will now be described, by way of example, with reference to the accompanying figures, in which: Figure 1 illustrates a cross-sectional schematic of an abatement apparatus according to the present invention; Figure 2 illustrates a flow diagram of a method of abating an effluent gas flow from a processing tool according to the present invention. Detailed Description Figure 1 shows a cross-sectional schematic of an abatement apparatus (1) according to the present invention. The abatement apparatus (1) comprises a treatment chamber (2). The treatment chamber (2) defines the region of the abatement apparatus where, when in use, the effluent gas stream (Gi) reacts with the gas flow (G2) to treat the effluent gas stream (G1). The treatment chamber (2) comprises an inlet (3) at a first end. In other embodiments, the treatment chamber (2) may comprise a plurality of inlets. The inlet (3) is configured to enable the effluent gas stream (G1) from the manufacturing processing tool (not shown) to enter the treatment chamber (2). Specifically, the inlet (3) is fluidly coupled to one or more vacuum pumps (not shown), wherein the vacuum pump(s) evacuate effluent gas stream (G1) from the processing tool and convey it into the abatement apparatus (1). The treatment chamber (2) comprises an outlet (4) at a second end, opposite the first end. The treatment chamber (2) is generally cylindrical. The treatment chamber (2) is partially defined by a first porous wall (5). The first porous wall (5) is generally tubular. The first porous wall (5) may be a metallic sheet with a plurality of perforations. The abatement apparatus further comprises a second porous wall (7). The second porous wall (7) is generally tubular. The second porous wall (7) may be a metallic sheet with a plurality of perforations. The second porous wall (7) generally surrounds the first porous wall (5). The first porous wall (5) and second porous wall (7) define therebetween a second chamber (8). The second chamber (8) is porous and allows gas flow therethrough. The second chamber (8) contains a relatively thermally conductive material (9). In this embodiment, the relatively thermally conductive material (9) is relatively thermally conductive particulate material. The second chamber (8) contains a packed bed of relatively thermally conductive particles (9). The gaps between the particles enable gas to flow through the second chamber (8). The particles (9) may be porous or substantially non-porous. The second chamber (8) contains heating elements (6). The heating elements (6) are located between the first porous wall (5) and the second porous wall (7). The heating elements (6) may be arranged throughout the second chamber (8). In this embodiment, the heating elements (6) are submerged within the relatively thermally conductive material (9). Preferably, the heating elements (6) are resistive heating elements. The heating elements (6) may be spaced to enable gas to flow through the second chamber (8) during use. In use, the heating elements (6) heat the relatively thermally conductive particles (9). Preferably, the heating elements (6) heat the relatively thermally conductive particles (9) to a temperature of from about 950 °C to about 980 °C. A third porous wall (10) generally surrounds the second chamber (8). The third porous wall (10) and second porous wall (7) define therebetween a third chamber (11). The third chamber (11) contains a relatively thermally insulating material (12). In this embodiment, the relatively thermally insulating material (12) comprises relatively thermally insulating particles. The third chamber (11) contains a packed bed of relatively thermally insulating particles (12). The gaps between said particles enable gas to flow through the third chamber (11). The particles may be porous or substantially non-porous. The relatively thermally insulating particles (12) may reduce heat transfer through the third chamber (11). The abatement apparatus (1) further comprises an outer wall (13) generally surrounding the third porous wall (10). The outer wall (13) is preferably a wall defining the treatment chamber housing. The outer wall (13) and third porous wall (10) define therebetween a plenum (14). The abatement apparatus (1) further comprises a gas inlet (15). The gas inlet (15) is arranged such that, during use, gas flow may be conveyed through the gas inlet (15) into the plenum (14), and from the plenum (14) into the third chamber (11). This may increase dispersion of the gas flow through the third chamber (11) and second chamber (8). The apparatus (1) is configured such that, in use, a gas flow (G2) is conveyed from the gas inlet (15) through the third chamber (11) and the second chamber (8) to the treatment chamber (2) where it reacts with the effluent gas stream (G1). The treated gas stream may exit the apparatus through the outlet (4) of the treatment chamber (2). Figure 2 shows a flow diagram of a method of abating an effluent gas flow from a processing tool according to the present invention. The method comprises the steps of providing an abatement apparatus according to any embodiment described herein (16). For example, the abatement apparatus may be that described in relation to Figure 1. Next, the one or more heating elements are operated to heat the relatively thermally conductive material within the second chamber (17). Preferably, during this step, the effluent gas stream is not being conveyed through the abatement apparatus. Once the one or more heating elements have heated the relatively thermally conductive material to the desired temperature, gas flow is conveyed from the gas inlet into the treatment chamber through the third chamber and the second chamber (18). Preferably, the gas flow comprises compressed dry air and / or nitrogen. Typically, the relatively thermally conductive material is heated to a temperature greater than about 500 °C, preferably greater than about 950 °C. The gas flowing across / through the relatively thermally conductive material that has been heated by the heating elements will heat the gas prior to it entering the treatment chamber. Next, as the effluent gas stream is conveyed through the treatment chamber, it is abated by reaction with the gas flow (19). Finally, the abated gas stream is conveyed through the outlet of the treatment chamber (20). For the avoidance of doubt, features of any aspects or embodiments recited herein may be combined mutatis mutandis. It will be appreciated that various modifications may be made to the embodiments shown without departing from the spirit and scope of the invention as defined by the accompanying claims as interpreted under patent law, including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a”, “an”, “the” or “said”, is not to be construed as limiting the element to the singular.

Claims

1. An abatement apparatus for treating an effluent gas stream from a manufacturing processing tool, comprising:a treatment chamber at least partially defined by a first porous wall, and comprising an inlet configured to enable an effluent gas stream from the processing tool to enter the treatment chamber;a second porous wall generally surrounding the first porous wall and defining therebetween a second chamber, the second chamber containing a relatively thermally conductive material, said second chamber being porous to allow gas flow therethrough;one or more heating elements configured to heat the relatively thermally conductive material;a third porous wall generally surrounding the second chamber and defining therebetween a third chamber, the third chamber containing a relatively thermally insulating material, said third chamber being porous to allow gas flow; and a gas inlet;wherein the apparatus is configured such that, in use, a gas flow is conveyed from the gas inlet through the third chamber and the second chamber to the treatment chamber where it reacts with the effluent gas stream.

2. The abatement apparatus according to claim 1, further comprising an outer wall generally surrounding the third porous wall, and defining therebetween a plenum.

3. The abatement apparatus according to claim 1 or 2, wherein the relatively thermally conductive material has a thermal conductivity of at least ten times the thermal conductivity of the relatively thermally insulating material.

4. The abatement apparatus according to any preceding claim, wherein the relatively thermally conductive material has a thermal conductivity greater than about 100 Wm_ 1K’1.

5. The abatement apparatus according to any preceding claim, wherein the relatively thermally conductive material contained in the second chamber is a relativelythermally conductive particulate matter, preferably a packed bed of relatively thermally conductive particulate matter.

6. The abatement apparatus according to claims 5, wherein the relatively thermally conductive particulate matter comprises silicon.

7. The abatement apparatus according to any preceding claim, wherein the relatively thermally insulating material has a thermal conductivity less than about 10 Wm^K'1, preferably less than about 1 Wm'1K'1, more preferably less than about 0.1 Wm'1K'1.

8. The abatement apparatus according to any preceding claim, wherein the relatively thermally insulating material contained in the third chamber is a relatively thermally insulating particulate matter, preferably a packed bed of relatively thermally insulating particulate matter.

9. The abatement apparatus according to claim 8, wherein the relatively thermally insulating particulate matter comprises pumice and / or micafil vermiculite.

10. The abatement apparatus according to any preceding claim, wherein the one or more heating elements are resistive heating elements and / or infra-red heating elements.

11. The abatement apparatus according to any preceding claim, wherein the one or more heating elements are configured to heat the relatively thermally conductive material to a temperature from about 500 °C to about 1200 °C, preferably from about 700 °C to about 1000 °C, more preferably from about 900 °C to about 1000 °C, most preferably from about 950 °C to about 980 °C.

12. The abatement apparatus according to any preceding claim, wherein the gas flow conveyed through the gas inlet comprises compressed dry air and / or nitrogen.

13. A method of abatement of an effluent gas stream from a manufacturing processing tool, comprising the steps of:a) providing an abatement apparatus according to any preceding claim;b) operating the one or more heating elements to heat the relatively thermally conductive material within the second chamber;c) conveying a gas flow from the gas inlet to the treatment chamber through the third chamber and the second chamber;d) abating the effluent gas stream with the gas flow in the treatment chamber; and e) conveying the abated gas stream through an outlet of the treatment chamber.

14. The method according to claim 13, wherein in step (b) the heating elements heat the relatively thermally conductive material to a temperature from about 500 °C to about 1200 °C, preferably from about 700 °C to about 1000 °C, more preferably from about 900 °C to about 1000 °C, most preferably from about 950 °C to about 980 °C.

15. The method according to claim 13 or 14, wherein the gas flow comprises compressed dry air and / or nitrogen.

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