GB2468784A

GB2468784A - Atmosphere control system for a waste treatment chamber

Info

Publication number: GB2468784A
Application number: GB1004694A
Authority: GB
Inventors: David Creighton Mcveigh
Original assignee: WASTEOLOGY SYSTEMS Ltd
Current assignee: WASTEOLOGY SYSTEMS Ltd
Priority date: 2009-03-19
Filing date: 2010-03-19
Publication date: 2010-09-22
Also published as: GB0904792D0; GB2468710A; GB201004694D0

Abstract

An atmosphere control system for a waste treatment chamber 10 accelerates the biodegrading process by supplying air or oxygen and water in varying amount to different treatment zones to promote biological breakdown of the waste. The chamber comprises first 40 and second 42 zones and, preferably, a third 44 zone. Air is delivered and extracted from the first zone and air is delivered and extracted from the second zone, wherein air extracted from the first zone is subsequently delivered to the second zone. The control system may also vary and control the temperature and humidity in each zone. In the first zone, waste 24 is introduced into the chamber and, thereby, the decomposition can be initiated. In the second zone, the decomposition has commenced but is not at an advanced stage. Finally, in the third zone, the decomposition process is advanced and the waste is progressing towards its final state in which it can be removed and finally disposed of.

Description

Improvements in and relating to Waste Treatment

Field of the Invention

The present invention relates to an atmosphere control system for a waste treatment chamber and to a method of controlling the atmosphere within a waste treatment chamber.

Background to the Invention

The disposal of domestic waste generally aims to prevent or avoid untreated domestic waste from being directly put into landfill sites. Accordingly, domestic waste may be initially treated in order for the waste to be broken down and at least partially composted. For economic reasons, it is preferred that the rate at which the organic composting action proceeds is as fast as possible. In order to accelerate the process it is known to incorporate measures in a waste treatment cycle where the waste is turned over periodically.

PCT/GB2009/000157 describes a waste treatment chamber for use with a waste turning machine. The waste treatment chamber includes a pair of parallel elongate walls, doors at both ends and a roof. The roof has a longitudinal gap with a flexible seal to allow a shaft or arm of a waste turning machine to project therethrough. The arm supports a turning drum which turns the domestic waste.

This, therefore, provides a substantially enclosed chamber where the waste can be turned to accelerate the decomposition. S...

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* It is an aim of the present invention to overcome at least one problem associated *.*S with the prior art whether referred to herein or otherwise. * *

: *.30 Summary of the Invention **

According to a first aspect of the present invention there is provided an atmosphere control system for a waste treatment chamber, the system comprising first air delivery means and first air extraction means for delivering and extracting air from a first treatment zone in the waste treatment chamber, the system further comprising second air delivery means and second air extraction means for delivering and extracting air from a second treatment zone in the waste treatment chamber and in which the second air delivery means is connected to the first extraction means in order for air to be extracted from the first treatment zone and then to be delivered to the second treatment zone by the second air delivery means.

Preferably the atmosphere control system comprises air pressure control means which may monitor andlor adjust the air pressure in each treatment zone.

Preferably the atmosphere control system comprises temperature control means which may monitor and/or adjust the temperature in each treatment zone.

Preferably the atmosphere control system comprises humidity control means which may monitor and/or adjust the humidity in each treatment zone.

The atmosphere control system may comprise an air supply inlet and an air extraction outlet. The atmosphere control system may comprise air flow means to cause air to flow through the air inlet.

The atmosphere control system may comprise an elongate lower conduit. The elongate lower conduit may be divided into a plurality of sections. Preferably 25 adjacent sections are divided by a valve to selectively enable (or prevent) air to flow between adjacent sections. The adjacent sections may be connected through air flow means which is arranged, in use, to cause air to flow between adjacent ** S. sections. The air flow means may comprise a fan or may comprise a booster unit.

: *..* 30 The atmosphere control system may comprise an elongate upper conduit. The S...

elongate upper conduit may be divided into a plurality of sections. Preferably adjacent sections are divided by a valve to selectively enable (or prevent) air to flow between adjacent sections. The adjacent section may be connected through air flow means which is arranged, in use, to cause air to flow between adjacent sections. The air flow means may comprise a fan or may comprise a booster unit.

Preferably the waste treatment chamber comprises three waste treatment zones.

The atmosphere control system may comprise a third air delivery means and a third air extraction means in order to deliver air and extract air from a third treatment zone.

The first air delivery means may comprise a delivery conduit which delivers air into a chamber located underneath a perforated floor member and preferably delivers air into two chambers located underneath respective perforated floor members.

Preferably the delivery conduit comprises one or more vents to deliver air into the or each chamber. Preferably the or each vent is variable to control the flow of air into the first treatment zone. The or each vent may comprise a variable controlled damper.

The delivery conduit preferably comprises a first section of an elongate lower conduit.

The first air extraction means may comprise a perforated air conduit and preferably comprises a plurality of perforated air conduits. Preferably the or each perforated air conduit is located adjacent to a roof member of the waste treatment chamber.

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Preferably the or each perforated air conduit comprises guard means which may S...

*..: be arranged, in use, to prevent waste from being propelled by a waste turner into the perforations. * * S S *5*S

Preferably the or each perforated air conduit communicates with an air communication passageway. -4..

Preferably the air communication passageway comprises a first section of an elongate upper conduit.

The second air delivery means may comprise a perforated air conduit and preferably comprises a plurality of perforated air conduits. Preferably the or each perforated air conduit is located adjacent to a roof member of the waste treatment chamber.

Preferably the or each perforated air conduit comprises guard means which may be arranged, in use, to prevent waste from being propelled by a waste turner into the perforations.

Preferably the or each perforated air conduit communicates with the air communication passageway which supplies air. Preferably the air communication passageway guides air from the first air extraction means to the second air delivery means.

The system may comprise a booster unit to generate airflow between the first air extraction means and the second air delivery means.

Preferably the air communication passageway comprises a second section of an elongate upper conduit.

The second air extraction means may comprise a chamber located underneath a 26 perforated floor member which is in communication with an air conduit and : preferably comprises two chambers located underneath respective perforated floor members which are in communication with an air conduit. S... S...

Preferably the air conduit comprises one or more vents to extract air out of the or : *o each chamber. Preferably the or each vent is variable to control the flow of air out S...

of the second treatment zone. The or each vent may comprise a variable controlled damper.

The air conduit may comprise a second section of an elongate lower conduit.

The third air delivery means may comprise a delivery conduit which delivers air into a chamber located underneath a perforated floor member and preferably delivers air into two chambers located underneath respective perforated floor members.

Preferably the delivery conduit comprises one or more vents to deliver air into the or each chamber. Preferably the or each vent is variable to control the flow of air into the third treatment zone. The or each vent may comprise a variable controlled damper.

Preferably the delivery conduit guides air from the second air extraction means to the third air delivery means. The system may comprise a fan (or booster unit) to generate airflow between the second air extraction means and the third air delivery means.

Preferably the delivery conduit comprises a third section of an elongate lower conduit.

The third air extraction means may comprise a perforated air conduit and preferably comprises a plurality of perforated air conduits. Preferably the or each perforated air conduit is located adjacent to a roof member of the waste treatment chamber.

: Preferably the or each perforated air conduit comprises guard means which may be arranged, in use, to prevent waste from being propelled by a waste turner into the perforations.

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: *** Preferably the or each perforated air conduit communicates with an air 555* communication passageway.

Preferably the air communication passageway comprises a third section of an upper conduit.

Preferably, the air generally moves upwardly in the first zone. The air may be arranged to generally move downwardly in the second zone. The air may be arranged to generally move upwardly in the third zone.

Preferably the atmosphere control system comprises a first operating mode wherein the waste treatment machine is not in operation and a second operating mode in which the waste treatment machine is operating. Preferably when the waste treatment machine is in operation the waste treatment machine moves from a first end of the waste treatment chamber to a second end and generally displaces the waste towards the second end.

Preferably the waste treatment chamber comprises two laterally spaced walls, closure members at each longitudinal end and a roof.

Preferably the air extraction outlet is in communication with a bio filter.

The atmosphere control system may comprise water delivery means in order to deliver the water into the waste treatment chamber. The water delivery means may be arranged, in use, to deliver water into the first zone and/or the second zone and/or the third zone.

Preferably the water delivery means may comprise an irrigation pipe. Preferably 2.5 the irrigation pipe is arranged, in use, to locate adjacent to a roof member of the waste treatment chamber and preferably, in use, is mounted to the roof of the waste treatment chamber. S...

The atmosphere control system may comprise a drainage system. * *30 * * *

Preferably the waste treatment chamber is arranged, in use, to contain the * atmosphere of the waste treatment chamber and preferably substantially maintains the atmosphere of the waste treatment chamber separate from the external atmosphere.

The atmosphere of the waste treatment chamber may be partitioned from the external atmosphere.

The portioning means may comprise a cover including a resealable opening through which waste treatment apparatus may extend.

Preferably the waste treatment chamber comprises a pair of parallel elongate walls, a roof spanning between the walls and doors at both ends of the chamber such that the interior volume of the chamber is substantially closed, wherein the roof comprises two roof sections projecting towards each other from respective walls and the roof sections are spaced apart to define a longitudinal opening running the length of the chamber, parallel to the walls and off set from the walls, the opening being normally closed by a flexible seal and wherein the longitudinal opening is of sufficient width to enable an operating arm of a machine to extend into the chamber through the longitudinal opening.

Preferably the waste treatment chamber comprises a cover to shroud the longitudinal opening.

The longitudinal cover opening may correspond with the longitudinal opening provided between the roof sections.

*25 Preferably the cover includes a longitudinal cover opening that is sealable. The :" longitudinal cover opening may be sealable to create gas tight seal.

Preferably the cover comprises a flexible material that is arranged, in use, to locate over the longitudinal opening. The cover may comprise a gas proof : ***0 membrane. I...

The cover may comprise a first strip of a flexible material secured to a first roof section and a second strip of a flexible material secured to a second roof section.

Preferably the two strips of flexible material define a longitudinal cover opening therebetween.

The or each strip of flexible material may be releasably secured to the respective roof section.

The cover may comprise a sealing system to seal the longitudinal cover opening in the cover. The sealing system may comprise a zip.

Preferably the flexible seal is arranged, in use, to be pushed aside by the arm as the machine travels along the chamber and then closes again once the arm has passed.

Preferably the longitudinal cover opening is opened prior to the arm of the machine travelling along the chamber. The longitudinal cover opening may then be resealed after the arm has travelled along the chamber.

Preferably each roof section comprises a cantilevered roof section.

Preferably the opening extends down the middle of the chamber.

Preferably the flexible seal is in two parts, each part being attached to one half of the roof, and the seal parts having rounded abutting portions.

2.5 Preferably the seal is of rubber.

* *.*** * * According to a second aspect of the present invention there is provided a waste *..: treatment chamber including an atmosphere control system wherein the waste treatment chamber comprises a first treatment zone and a second treatment zone, : .30 the system comprising first air delivery means and first air extraction means for * delivering and extracting air from the first treatment zone, the system further comprising second air delivery means and second air extraction means for delivering and extracting air from a second treatment zone and in which the second air delivery means is connected to the first extraction means in order for air to be extracted from the first treatment zone and then to be delivered to the second treatment zone by the second air delivery means.

Preferably the waste treatment chamber comprises a third treatment zone. The system may comprise third air delivery means and third air extraction means for delivering and extracting air from the third treatment zone.

According to a third aspect of the present invention there is provided a method of controlling the atmosphere in a waste treatment chamber, the method comprising delivering and extracting air from a first treatment zone in the waste treatment chamber, the method further comprising delivering and extracting air from a second treatment zone in the waste treatment chamber and in which the air extracted from the first treatment zone is communicated to, and delivered into, the second treatment zone.

The method may comprise delivering and extracting air from a third treatment zone. Preferably the air extracted from the second treatment zone is communicated to, and delivered into, the third treatment zone.

According to a fourth aspect of the present invention, there is provided a waste treatment chamber comprising a pair of parallel elongate walls, a roof spanning between the walls and doors at both ends of the chamber such that the interior volume of the chamber is substantially closed, wherein the roof comprises two roof sections projecting towards each other from respective walls and the roof sections are spaced apart to define a longitudinal opening running the length of the chamber, parallel to the walls and off set from the walls, the opening being ***.

normally closed by a flexible seal and wherein the longitudinal opening is of sufficient width to enable an operating arm of a machine to extend into the : ..30 chamber through the longitudinal opening and, in which, the waste treatment I...

* chamber comprises a cover to shroud the longitudinal opening. ***

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Preferably the cover includes a longitudinal cover opening that is sealable. The longitudinal cover opening may be sealable to create gas tight seal.

Preferably the cover comprises a flexible material that is arranged, in use, to locate over the longitudinal opening. The cover may comprise a gas proof membrane.

wZ5 Preferably the longitudinal cover opening is opened prior to the arm of the *S..

machine travelling along the chamber. The longitudinal cover opening may then be resealed after the arm has travelled along the chamber. S...

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Preferably each roof section comprises a cantilevered roof section.

* ..30 * S S S...

* Preferably the opening extends down the middle of the chamber. **S

Preferably the flexible seal is in two parts, each part being attached to one ha!f of -11 -the roof, and the seal parts having rounded abutting portions.

Preferably the seal is of rubber.

Brief DescriDtion of the Drawings The present invention will now be described, by way of example only, with the reference to the drawings that follow, in which: Figure 1 is a schematic cutaway view of a preferred embodiment of a waste treatment chamber including a waste turning machine.

Figure 2 is an end view of a waste treatment chamber.

Figure 3 is a plan schematic view of a layout of a preferred embodiment of a waste treatment chamber.

Figure 4 is a lateral cross sectional view through B-B of Figure 3 of a preferred embodiment of any waste treatment chamber.

Figure 5 is a longitudinal cross sectional view through C-C of Figure 3 of a preferred embodiment of a waste treatment chamber.

Figure 6 is a longitudinal cross sectional view through A-A of Figure 3 of a .5 preferred embodiment of a waste treatment chamber. * *

Figure 7 is an end schematic view of a preferred embodiment of a waste treatment **** chamber.

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: .30 Figure 8 is a plan schematic view of a waste treatment plant incorporating a * plurality of waste treatment chambers. 5.

Figure 9 is a cross sectional view of another embodiment of a water treatment chamber.

Figure 10 is a cross sectional view of a preferred embodiment of a cover for a waste treatment chamber.

Description of the Preferred Embodiments

As shown in Figure 1 and Figure 2, a waste treatment chamber 10 includes a pair of parallel elongate side walls 12, 14, a roof 16 and closure members 18, 20 at each longitudinal end of the chamber 10. The closure members 18, 20 comprise doors which enable domestic waste to be introduced at a first end of the chamber and for the broken down waste to be removed from the chamber 10 at a second end.

Whilst in the chamber 10, a waste turning machine 22 is arranged to pass over the waste 24. The waste turning machine 22 comprises a turner drum 26 which is located at a lower end of an arm 28. The turner drum 26 rotates in order to turn the domestic waste to thereby accelerate the decomposition process.

As described in PCT/GB2009/000157, the roof 16 comprises a cantilevered roof having a first section 30 extending inwardly from the first wall 12 and a second section 32 extending inwardly from the second wall 14. A flexible rubber seal is mounted along the central gap between two roof sections 30, 32. In use, the arm 28 of the waste turning machine 22 locates within the flexible seal in order to .25 minimise the air escaping from the waste treatment chamber 10 into the external atmosphere. However, with such a system a gap may be created in front of and behind the arm 28 as the arm passes along the longitudinal gap. S. S...

The flexible rubber seal comprises a first elongate rubber member 34 projecting : *..30 inwardly from the first roof section 30 and a second elongate rubber member 36 a...

projecting inwardly from the second roof section 32. The two elongate rubber members 34, 36 are arranged to abut each other in normal use but will be displaced as the arm 28 travels along the longitudinal gap between the two roof sections 30, 32.

The present invention will now be described in more detail with particular reference to Figure 1 to Figure 7.

One aim of the present invention is to provide atmospheric control mean in order to control the breakdown of the domestic waste within the waste treatment chamber 10. In particular the present invention aims to accelerate the process and to supply air/oxygen and water in varying amount to different treatment zones to promote the biological breakdown of the waste. The control system may also vary and control the temperature in each zone. In the present invention, the waste treatment chamber 10 effectively provides three different zones 40, 42, 44 and these comprise an initial zone 40, intermediary zone 42 and a final zone 44. The atmosphere control system comprises a computer controlled system which enables the system to be easily and accurately controlled by the operator. The treatment zones within the waste treatment chamber are not physically separated from each other by partitions or dividers.

In the first zone 40, the domestic waste 24 is newly introduced into the chamber 10 and, thereby, the decomposition needs to be initiated and commenced. In the intermediary zone 42, the decomposition has commenced but is not at an advanced stage. Finally, in the third zone 44, the decomposition process is advanced and the domestic waste 24 is progressing towards its final state in which it can be removed and finally disposed of.

* .2.5 I...

In the preferred embodiment, the longitudinal length of the first zone 40 is 5 metres, the longitudinal length of the second zone 42 is 20 metres and the * .a* : longitudinal length of the third zone 44 is 20 metres. However, it is appreciated that the lengths of these zones 40, 42, 44 may be varied and, in particular, may be : *3O variant depending upon the nature of the waste being treated within the waste *. .* * treatment chamber 10. S..

The waste treatment chamber 10 comprises an elongate lower conduit 46 which -14 -extends longitudinally along the length of the chamber 10 within a false floor. The elongate lower conduit 46 is effectively divided into three sections 46a, 46b and 46c. Each section 46a, 46b, 46c resides in and is operational in a respective zone within the chamber 10.

The atmosphere control system provides chambers 54 located on either side of the elongate lower conduit 46. The elongate lower conduit 46 may either deliver air into these chambers 54 or extract air from these chambers 54 depending upon the location within the chamber 10. The elongate lower conduit 46 is provided with valves 56 (variable controlled dampers) to regulate the flow of air between the elongate lower conduit 46 and the chambers 54. The valves 56 comprise louvered vents which can be adjusted.

The chambers 54 include perforated panels 58 which support the waste 24 thereon and which act as the floor to the waste treatment chamber 10. The perforated panels 58 comprise composite plastic/concrete panels. The perforations enable air (and other fluids) to flow between the chambers 54 and the waste treatment chamber 10. Longitudinally adjacent chambers are separated from each other by suitable partitions 60.

The atmosphere control system comprises an air inlet 62 and fan 64 which is arranged to supply air to the elongate lower conduit 46. The elongate lower conduit may also have an exhaust pipe 98 connect at the rear end of the waste treatment chamber 10. The exhaust pipe 98 may be connected to the elongate *Q, lower conduit 46 through a valve which may normally be closed. As will be explained later, in the normal mode of operation air flows out of the elongate lower conduit into the third treatment zone and not straight out of the exhaust pipe 98. 0*.*

: However, in an emission control mode the valve may be opened to increase the * airflow out of the waste treatment chamber 10. : *°

The waste treatment chamber 10 also comprises an elongate upper conduit 48 which extends longitudinally along the length of the chamber 10. The elongate upper conduit 48 locates externally from the chamber 10 and locates along one side of the interface between a roof member and wafl. The elongate upper conduit 48 is effectively divided into three sections 48a, 48b, 48c. Each section 48a, 48b, 48c resides in and is operational in a respective treatment zone within the chamber 10. The elongate upper conduit 48 is a steel pipe/plenum.

The atmosphere control system also comprises a number of perforated air conduits 50 which branch off from the elongate upper conduit 48. The function of these perforated air conduits 50 will depend upon the location within the chamber and the perforated air conduits 50 may function as an air delivery means or an air extraction means for a respective zone 40, 42, 44. The perforated air conduits comprise steel pipes.

The perforated air conduits 50 are arranged to be located adjacent to roof struts (not shown) that support the cantilevered roof 16. The system also comprises guard members or shields which are arranged to prevent debris and waste from blocking the perforations. In particular the shield comprises an elongate shield which locates parallel to but spaced from one side of each perforated air conduits 50. The elongate shield may also extend below the perforated air conduits 50.

When the waste turning machine 22 is in operation, the drum 26 displaces waste rearwardly and the shields are arranged to prevent this debris from blocking the perforations. Accordingly, the shields do not need to completely surround the perforated air conduits 50.

The atmosphere control system comprises an irrigation system in order to deliver **? water (and/or another fluid) to the waste within the waste treatment chamber 10. S...

The irrigation pipe may comprise a 50mm steel pipe. The irrigation system comprises an irrigation pipe 52 which is suspended from the roof 16 within the * S I. chamber 10. The irrigation pipe 52 comprises a number of spaced apart nozzles to deliver the water. The nozzles may be controlled by a control system to vary : .30 the volume of water delivered. The irrigation system also provides the waste treatment chamber 10 with a fire suppressant system to control and extinguish S..

fires within the waste treatment chamber 10.

-16 -As shown in Figure 3 to Figure 7, the basic construction of the waste treatment chamber 19 comprises a foundation 92 which comprises a foundation slab 94.

The elongate lower conduit 46 is formed by a casing 96 within a void of the foundation slab 94. This thereby creates the chambers 54 on either side of the elongate lower conduit 46. These chambers 54 are then completed by the inclusion of the perforated panels 58. The walls 12, 14 include the ducting/conduits for rainwater removal, low voltage electrical supply, air extraction from the elongate upper conduit 48 etc. Accordingly, the waste treatment chamber is effectively a modular unit that can be relatively easily constructed without bespoke and time consuming construction processes. The system is designed within general civil engineering tolerances and the 5m wide chamber may have a tolerance (variance) of 20mm. Accordingly, such a waste treatment chamber is not required to be. built to exacting precision engineering tolerances.

In use, air is supplied to the waste treatment chamber by an air inlet 62. This may be driven by a fan or other airflow means. The air enters the elongate lower conduit 46 in the first treatment zone 40. The air passes through the variable controlled dampers 56 and into the chambers 54 located on either side of the elongate lower conduit 46 and underneath the perforated floor sections. The air then flows through the perforations into the relatively new waste within the first treatment zone 40.

The perforated air conduits 50 mounted on the roof 16 then extract the air from the first treatment zone 40 and this air then flows through the upper air conduit 48 *...c,5 (possibly aided by a booster unit 74 or fan) and into the perforated air conduits 50 *SS mounted on the roof 16 in the second treatment zone 42. The air enters the S.....

* second treatment zone 42 and penetrates the waste 24 in an intermediate phase S.,.

of decomposition.

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* *,30 The air is extracted from the second treatment zone 42 through the perforations in the false floor 58. The air is drawn into the second section 46b of the elongate *..

* lower conduit 46 through valve members 56. The air then flows through the lower elongate conduit 46 and in to the third treatment zone 44.

The system includes airflow means in the form of a fan 64 in order to move the air from the second treatment zone 42 to the third treatment zone 44. This fan 64 may be mounted externally with respect to the waste treatment chamber 10. This improves the access to the fan 64 in the event of a failure or if there is a fire. The fan 64 is a flameproof fan since the waste treatment chamber 10 generates heat due to the decomposition process and this present a fire risk.

The air flows in to the third treatment zone 44 in the same manner as in the first treatment zone 40. The air exits the elongate lower conduit 46 through a number of variable controlled dampers 56. The air then locates in the chambers 54 underneath the perforated floor panels 58. The air flows through these perforations and through the waste 24.

The air is extracted from the third treatment zone 44 through the perforated air conduits 50 mounted on the roof 16 of the waste treatment chamber 10 in the third treatment zone 44.

The atmosphere control system includes an extractor fan 90 to draw the air from the third treatment zone 44 and to propel the air towards the bio-filter 68.

The atmosphere control system comprises feedback means to feedback atmospheric parameters to the control system. In particular, the temperature, humidity and/or pressure may be measured in each treatment zone and the results are communicated to the control means. The sensors may be permanently mounted in each of the treatment zones. Alternatively, the sensors may be placed temporarily within the chambers to monitor the parameters. For example, *.....

* temperature probes may be inserted through the roof into each zone to obtain ** temperature readings.

* .30 * In the normal mode of operation when the waste is simply naturally decomposing in the waste treatment chamber 10, air flows upwardly through the first treatment **.

* zone 40 and the air is then transferred into the second treatment zone 42 where the air travels downwardly and then finally the air is transferred into the third treatment zone 44 where the air travels upwardly before exiting the waste treatment chamber 10.

The air finally exits the waste treatment chamber 10 through an air outlet 66 which is connected to a bio-filter 68 which is arranged to filter particles and other decontaminants from the exiting air.

In an active mode, the waste turning machine 22 operates and moves along the waste treatment chamber 10 turning the waste 24 and generally displacing the waste 24 towards the rear end (the third treatment zone 44) of the waste treatment chamber 10. When the turning drum 26 is in operation, this creates significant airflow and turbulence within the waste treatment chamber 10. This can lead to a build up of pressure which can force air out of the longitudinal flexible seal 34, 36 located along the roof 16 of the waste treatment chamber 10. In particular, air may be forced out of the gap 34, 36 located either side of the arm 26 which separates the rubber seal members 34, 36.

In order to reduce and minimise the inadvertent flow of air out of the waste treatment chamber 10, the valves 56, dividers 60, 80, booster unit 74, fans 64, 70 and flow pathway are altered in the system to provide a more direct and easy flow of air through the waste treatment chamber 10. In particular, the air inlet fan 70 may be switched off and the dividers 60, 80 dividing the elongate upper conduit 48 and the elongate lower conduit 46 are opened. In addition, the booster units 74 or fans located in the elongate upper conduit 48 are activated. This increases the ability of air to flow to the rear of the waste treatment chamber 10 and to reduce the build up of localised pressure. This mode is an emission control mode which * ** S S. * prevents or minimises contaminated air being emitted to the external atmosphere and restricts the emission of volatile organic compounds. In this mode the atmosphere control system encourages air to enter into the waste treatment * chamber around the arm 28 of the waste turning machine 22 rather than to exit at :.. this point. *5.

The waste treatment chamber 10 also comprises drainage means to drain water and other liquids from the waste treatment chamber 10. The drainage means comprise channels or gulleys 76 located in the chambers 54 below the perforated floor sections 58. These gulleys 76 are sloped in order for liquids to naturally flow out of the waste treatment chamber 10 for collection and/or disposal.

The gulleys 76 are connected to downpipes 82 in the second and third treatment zones 42, 44. The downpipes 82 enable the liquids to flow down into underground pipes 80 for removal of the drainage liquids. The drainage gulley 76 in the first treatment zone 40 may simply flow out the front end of the waste treatment chamber 10.

The waste treatment chamber 10 also comprises a drainage system on the external roof 16 in order to collect rainwater and other precipitation. The drainage system comprises a gutter 78 located on either side of the sloping roof members which collect the precipitation and are naturally sloping to cause the liquids to flow to the front end of the waste treatment chamber 10. The gutters 78 may be connected to downpipes 84 located within the walls 12, 14 at the front end of the waste treatment chamber 10.

The waste treatment chamber 10 also comprises ducting 86 or conduits for the electrical supply to operate the various electrically operated mechanisms in the waste treatment chamber 10. These electrical ducts 86 or conduits may be located within the walls 12, 14 of the waste treatment chamber 10.

The walls 12, 14 may also include exit pipes 88 within the structure. For example, . the exit pipe 88 for the elongate upper conduit 48 is located within one waIl 12.

S..... * .

*.*. . . As shown in Figure 8, a waste treatment plant 100 may include a number of waste treatment chambers 10 located side by side. This would enable a single waste * turning machine 22 to service a number of waste treatment chambers 10. In :. addition, the air outlets 66 or exhausts of a number of waste treatment chambers may all be connected to a single bio-filter 68 in order for the single bio-filter 68 to efficiently service a number of waste treatment chambers 10. In particular, the exhaust pipes 88, 98 from a waste treatment chamber 10 may be connected to a manifold 102. This manifold may accept the exhaust pipes 88, 98 from a number of waste treatment chambers 10. The manifold 102 is connected at spaced intervals to the bio-filter 68 through fans 90.

When one of the waste treatment chambers 10 is being serviced by the waste turning machine 22, the fans 90 may be directed to provide the maximum extraction for the waste treatment chamber 10 being serviced. This may also involve the shut down or restriction of the exhaust pipes 88, 98 of the other waste treatment chambers 10. In addition, the exhaust pipe 98 may be fully opened to increase the air flow out of the waste treatment chamber 10 being serviced.

In the preferred embodiment, the system comprises a single elongate upper conduit which extends along one side of the waste treatment chamber. However, in alternative embodiments there may be two or more such conduits. Similarly, in the preferred embodiment these is a single irrigation pipe but alternative embodiments may have two or more irrigation pipes.

In a further embodiment, the waste treatment chamber may include a heat exchange system to extract heat energy from the chamber. In particular, a heat exchange unit may be located in the third treatment zone 44 to extract the heat energy.

As shown in Figure 9 and Figure 10, the waste treatment chamber 10 comprises a first rubber member 34 secured on the inner edge of the first roof section 30 and a second rubber member 36 secured on the inner edge of the second roof section * 32. The rubber members 34, 36 define a longitudinal slot therebetween through S... . . . which a part of a waste turning machine 22 may extend into the waste treatment chamber 10. The waste treatment chamber 10 also includes a cover which is * arranged to shroud this longitudinal opening and, in particular, to contain the gases within the chamber 10. The atmosphere within the chamber is partitioned. *.,

from the external atmosphere which aids the decomposition process and also contains any odours etc. The cover includes a!ongitudinal cover opening which is resealable. The longitudinal cover opening corresponds with the longitudinal opening provided between the roof sections such that, when required, the arm of the waste turning machine extends through both the longitudinal cover opening and the opening between the roof sections when the waste turning machine 22 is in operation.

The longitudinal cover includes a first strip 110 and a second strip 112. Each strip 110, 112 comprise a strip of a flexible material and specifically a strip of a flexible gas proof membrane. The longitudinal cover also includes a sealing system in order to create a seal between the first strip 110 and the second strip 112. In the preferred embodiment, the sealing system comprises a gas proof zip closure 114.

Accordingly, when the waste turning machine 22 is not in use, the zip closure 114 is closed in order to partition the internal atmosphere from the external atmosphere. However, when the waste turning machine 22 is to be used, the zip 114 can be quickly and easily operated in order for the arm of the waste turning machine 22 to be able to extend through the longitudinal openings and into the inside of the waste treatment chamber 10.

Each flexible strip 110, 112 are releasbly secured to respective roof sections 30, 32. The flexible strips 110, 112 may be of any suitable width and the aim is to provide a zip closure that corresponds with the opening between the roof sections 30, 32. As shown in Figure 10, an outer edge of the first flexible strip 110 comprises a retaining portion 116 which is arranged to be engaged in a retaining member 117 secured to the first roof section 30. The retaining member 117 comprises an aluminium profiled extrusion. Similarly, the second flexible strip 112 * comprises a retaining portion 118 which is arranged to be engaged in a retaining *. member 119 which may comprise an aluminium profiled extrusion. The retaining members 117, 119 are fixed to the respective roof sections 34, 36. * **

The cover provides a gas proof seal zip 114. The aim is to manually open and *S* * close the zip 114 along the full length of the roof before and after the waste turning -22 -machine 22 is used. Provided the entry and exit doors for the waste are sealed by a rubber strip or other suitable sealing system, this additional gas proof seal would enable the tunnel to be used for anaerobic use as well as aerobic use. The cover will also eliminate any potential odours escaping from the decomposing waste. S... * S S...

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Claims

CLAIMS1. An atmosphere control system for a waste treatment chamber, the system comprising first air delivery means and first air extraction means for delivering and extracting air from a first treatment zone in the waste treatment chamber, the system further comprising second air delivery means and second air extraction means for delivering and extracting air from a second treatment zone in the waste treatment chamber and in which the second air delivery means is connected to the first extraction means in order for air to be extracted from the first treatment zone and then to be delivered to the second treatment zone by the second air delivery means.
2. An atmosphere control system for a waste treatment chamber according to Claim I comprising air pressure control means which monitors the air pressure in each treatment zone.
3. An atmosphere control system for a waste treatment chamber according to Claim I or Claim 2 comprising temperature control means which monitors the temperature in each treatment zone.
4. An atmosphere control system for a waste treatment chamber according to any preceding claim comprising humidity control means which monitors the humidity in each treatment zone.
5. An atmosphere control system for a waste treatment chamber according to any preceding claim comprising three waste treatment zones. * S S...
6. An atmosphere control system for a waste treatment chamber according to any 0 preceding claim comprising a third air delivery means and a third air extraction means in order to deliver air and extract air from a third treatment zone. * *. * . . *1SS *S.

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7. An atmosphere control system for a waste treatment chamber according to any -24 -preceding claim in which the first air delivery means may comprise a delivery conduit which delivers air into a chamber located underneath a perforated floor member.
8. An atmosphere control system for a waste treatment chamber according to Claim 7 in which the delivery conduit comprises one or more vents to deliver air into the chamber.
9. An atmosphere control system for a waste treatment chamber according to Claim 8 in which the or each vent comprises a variable controlled damper.
10. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the first air extraction means comprises a plurality of perforated air conduits.
11. An atmosphere control system for a waste treatment chamber according to Claim 10 in which each perforated air conduit comprises guard means which is arranged, in use, to prevent waste from being propelled by a waste turner into the perforations.
12. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the system comprises a booster unit to generate airflow between the first air extraction means and the second air delivery means.
13. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the air generally moves upwardly in the first zone. S...
14. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the air is arranged to generally move downwardly in the second zone. * ..
15. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the air is arranged to generally move upwardly in a -25-.third zone.
16. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the atmosphere control system comprises a first operating mode wherein the waste treatment machine is not in Operation and a second operating mode in which the waste treatment machine is operating.
17. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the atmosphere control system comprises a drainage system.
18. An atmosphere control system for a waste treatment chamber according to any preceding claim in which the waste treatment chamber comprises a pair of parallel elongate walls, a roof spanning between the walls and doors at both ends of the chamber such that the interior volume of the chamber is substantially closed, wherein the roof comprises two roof sections projecting towards each other from respective walls and the roof sections are spaced apart to define a longitudinal opening running the length of the chamber, parallel to the walls and off set from the walls, the opening being normally closed by a flexible seal and wherein the longitudinal opening is of sufficient width to enable an operating arm of a machine to extend into the chamber through the longitudinal opening.
19. An atmosphere control system for a waste treatment chamber according to Claim 18 in which the waste treatment chamber comprises a cover to shroud the longitudinal opening. * ..S * *
20. A waste treatment chamber including an atmosphere control system wherein *.**** * the waste treatment chamber comprises a first treatment zone and a second :r treatment zone, the system comprising first air delivery means and first air *.30 extraction means for delivering and extracting air from the first treatment zone, the * system further comprising second air delivery means and second air extraction means for delivering and extracting air from a second treatment zone and in which **S the second air delivery means is connected to the first extraction means in order -26-for air to be extracted from the first treatment zone and then to be delivered to the second treatment zone by the second air delivery means.
21. A waste treatment chamber according to Claim 20 in which the waste treatment chamber comprises a third treatment zone.
22. A method of controlling the atmosphere in a waste treatment chamber, the method comprising delivering and extracting air from a first treatment zone in the waste treatment chamber, the method further comprising delivering and extracting air from a second treatment zone in the waste treatment chamber and in which the air extracted from the first treatment zone is communicated to, and delivered into, the second treatment zone.
23. A method of controlling the atmosphere in a waste treatment chamber according to Claim 22 comprising delivering and extracting air from a third treatment zone.
24. An atmosphere control system for a waste treatment chamber substantially as herein described with reference to, and as shown in, any of the accompanying drawings.
25. A waste treatment chamber including an atmosphere control system substantially as herein described with reference to, and as shown in, any of the accompanying drawings.
26. A method of controlling the atmosphere in a waste treatment chamber substantially as herein described with reference to, and as shown in, any of the *.....* accompanying drawings. S... *..S *SS * S. * S S 55SSS S..S