WO2005011946A1

WO2005011946A1 - Relocatable reclaiming plant and process

Info

Publication number: WO2005011946A1
Application number: PCT/AU2004/001000
Authority: WO
Inventors: William Dowdle
Original assignee: T-Systems Australia Pty Ltd
Priority date: 2003-08-01
Filing date: 2004-07-28
Publication date: 2005-02-10
Also published as: AU2003904009A0

Abstract

A transportable and relocatable on site plastics reclaiming plant including a plurality of interdependant demountable processing modules adapted to be assembled together, to comprise the reclaiming plant and wherein the assembly of the processing modules can be disassembled for transport and relocation to other sites.

Description

RELOCATABLE RECLAIMING PLANT AND PROCESS

FIELD OF INVENTION This invention relates to reclaiming plastics, in particular but not limited to a re-locatable reclaiming plant and process of using the same that is directed to reclaiming polyethylene drip irrigation tape and mulch used in the horticultural and agricultural industries.

BACKGROUND ART The use of thin walled polyethylene (PE) tubing for drip irrigation tape or tubing and mulching is known in the horticultural and agricultural industries. As an example, along the eastern seaboard of Australia, approximately 2500 tonnes of thin walled polyethylene drip irrigation tape also commonly referred to as drip tape and mulch, both herein referred to as PE material is used and disposed of annually. Of this volume approximately half is drip tape and the other half comprises a combination of drip tape and mulch material.

A major issue facing the horticultural industry is the sustainable disposal of the PE material. Current disposal methods include on farm burning or storage or dumping in local council or other landfill sites. A major problem facing a plastic recycling organisation targeting the processing for disposing of such material is the geographically diffuse nature of the horticultural industry itself, in particular there is the problem of the logistics of identifying where the material is and then obtaining it for the processing steps.

There is a strong environmental push towards a change in prior methods of disposing of PE material from several quarters, which includes various environmental protection agencies (EPA) whose intervention invariably prohibits growers from burning plastics on farms. Furthermore there is the problem of the high cost of landfill and charges imposed by local councils to growers, which although may be as small as AUD40 per tonne, does not reflect the true cost of the landfill. Councils are in fact reluctant to put this material into landfill. In addition there is the continued community focus towards objecting to any contribution to environmental contamination. Finally, because of the problems and costs associated with disposal, there are grower concerns towards the operational sustainability of the continued use of PE materials for agricultural and horticultural applications.

Presently there are no current solutions that provide for an economically viable or environmentally sustainable outcome for the disposal of PE materials. Current methods of disposal include on farm burning or storage, both of which have the potential to contaminate the environment. Dumping of the material into local council landfill sites wherein the bulky nature of the plastic material for example, 4 tonnes of non-compacted material equates to sixty cubic meters, makes it inefficient to use as landfill. Furthermore, local councils are unable to invest in regionally situated recycling plants because no one region in Australia generates an adequate volume to make such an investment economically viable. The same considerations would apply to most countries where agricultural and horticultural regions are spread over a large geographical area. Presently in Australia there are currently two plastic recycling or reclaiming plants, one in North Queensland and the other in Victoria, which involve fixed plants that locally target the processing for disposal of drip irrigation tape and plastic mulch. These organisations are by no means solving the broader issue of disposal of PE materials at a national level.

Allied to the disadvantages of fixed recycling or reclaiming plants not providing a sustainable solution in solving a broader national problem of disposal are more localised problems. The potential recyclers wishing to process the PE material face a number of significant barriers. Firstly, the PE material needs to be loaded and transported in bulk from the farms to the recycling or reclaiming plant. Secondly, manufacturing plants using reclaimed polyethylene are not designed to remove and clean the amount and type of contaminates found on this type of PE material when it is discarded after being used. Finally, attempts at reclaiming this type of PE material, prior to the process of the present invention have resulted in the PE material being reduced to a flake form, typically 0.5cm in diameter, making it nearly impossible to compact, and therefore more awkward and expensive to transport to recycling plants for use in manufacturing. The problems can be summarised under the following headings: Transporting unprocessed material By having a fixed recycling and reclaiming plant, unprocessed material has to be transported over long distances. The very nature or bulkiness of the unprocessed material makes it expensive to transport. These fixed plants therefore are limited to only accessing PE material that is geographically close to them.

Transporting contaminates such as dirt and plant materials Approximatel thirty percent of the total weight of unprocessed PE material is made up of dirt and organic plant matter. Transporting these waste materials with the unprocessed plastic adds to the lack of viability in transporting the PE material over long distances.

Transfer of soil and plant borne diseases and insects Transporting soil and plant material contaminates has the potential of transferring disease and insects from one region to another.

Disposal of soil vegetative and water waste Because the plastic material is used in agriculture there is the potential for chemical contamination (especially from fungicides, herbicides and insecticides), of the waste products typically soil, vegetative material and water. These materials need to be stored in bunded areas and tested for chemical contamination on a regular basis. If chemical contaminates are found in unacceptable high levels the waste will need to be treated accordingly.

OBJECT OF INVENTION The object of the present invention to seek to ameliorate some of the problems associated with recycling polyethylene materials or to at least provide the public with a useful choice. It is a principal object of the present invention is to provide a portable or re-locatable reclaiming plant and process that removes and contains all contaminates, cleans and reduces the polyethylene material to an appropriate size and shape necessary for immediate use by the recycler which can compact and bail it ready for transport to fixed recycling plants to be used in the manufacture of further polyethylene products. STATEMENT OF INVENTION In one aspect, the invention resides in a transportable and relocatable on site plastics reclaiming plant including a plurality of interdependent demountable processing modules adapted to be assembled together, to comprise the reclaiming plant and wherein the assembly of the processing modules can be disassembled for transport and relocation to other sites. Preferably each processing module includes separately or in combination;

conveyer means adapted to convey used polyethylene material typically drip irrigation tape and mulch to be processed,

metal detection means adapted to detect metal contaminates in the polyethylene material prior to shredding,

shredder means adapted to shred the polyethylene material,

trommel means adapted to remove soil and plant matter from the shredded polyethylene material,

granulation means adapted to granulate the shredded polyethylene material,

liquid typically water washing means adapted to wash the granulated polyethylene material,

drying means, typically drying trommel means, for drying the washed granulated polyethylene material,

hopper means for collecting and tunneling the dried granulated polyethylene material, compacting means for compacting the dried granulated polyethylene material, tunneled from the hopper means, (there is nothing after this comma) bailing means for bailing the compacted polyethylene material into bails, Preferably there are complementary connection means for assembling together the de-mountable processing units.

Preferably, there is control means adapted to control and coordinate the operation of the processing units when assembled together to comprise the reclaiming plant.

Preferably, the control means is microprocessor control means wherein in operation by detecting the weight or volume of polyethylene material processed by the various processing modules controls the speed of the conveyers and the rate at which the material is processed by the various processing modules.

Preferably, the microprocessor control means receives information from sensors positioned strategically on the various processing modules.

For example, a sensor placed across the feed hopper of the granulator. If the sensor detects a build up of material entering the granulator, it stops the main conveyer, stops the in-feed conveyer and trips the shredder into reverse awaiting immediate restart in the forward direction. When the material clears the sensor, the microprocessor control means restarts the above mentioned units.

In another example, there can be a backpressure sensor for the air blower. This sensor can auto-gate the airflow to either the cyclone feed or the search bin so that it can regulate the air speed required for maximum efficiency.

In another example, a sensor can be placed across the out-feed of the drying trommels. In the event that the processed polyethylene backs up, all processors prior to the drying trommel stop and allow it to catch up. The microprocessor control means in response to the sensor signal stops the second drying trommel as well as the first drying trommel. Also stopped are the wash plant means, the granulator means, although the air blower is kept running, the dirt extraction trommel, the main conveyer, the shredder and the in-feed conveyer (or trough conveyer).

When the blockage is cleared, the various processing units mentioned above are started in the above order.

There can be an overflow sensor on the surge bin wherein the same processing units as previously mentioned for the sensor across the out-feed of the drying trommel are stopped. To control the flow from the pumps to the wash tank, there can be flow meters, which control the flow of water entering the wash plant. The flow of water in the first drying trommel can be controlled by a flow meter and solenoids. This controls the main valve, which slows down or increases water flow as required, for example, during the auto backflush where there is a large flow variation before and after the backflush.

If an adequate flow can not be achieved all processors prior to wash plant are shut down. Once adequate flow rate is achieved, the processing modules restart in the stages preferably as follows; the granulator is restarted first, then the dirt extraction trommel, then the main conveyer, then the shredder, then finally the in-feed conveyer.

A moisture sensor can be placed between the out-feed bin of second drying trommel and the surge bin. If adequate drying has not been achieved all modules prior to the first drying trommel are shut down and the undried polyethylene material is redirected back to the first drying trommel for additional drying. Further drying trommels can also be added to improve the drying process. , All available air from the primary blower is required for this task to maximise the speed of drying. Following a shut down, there can be a staged restart of the processing units as mentioned previously.

There can be a sensor placed on the dirt extraction trommel wherein as waste from the dirt extraction trommel exits on the conveyer, it is redirected into a finer screening process to enable the capture of smaller plastic particles. The captured plastic re-enters the process directly at the wash plant stage.

There can be a control sensor on the shredder. This sensor would stop feeding material entering the shredder from the feed conveyer, so that there is a time delay between bundles of material entering the shredder.

Preferably the conveyer means comprises a flat belt conveyer for conveying the unprocessed polyethylene material to the shredder means and a trough conveyer for conveying the shredded polyethylene material to the trommel means.

Preferably the conveyer means is a blower and pipe for conveying granulated PE material from the granulation means to the liquid washing means.

Preferably the metal detection means is an overhead fixed metal detector which is activated when any pieces of metal are included with the polyethylene material to be processed and wherein on detection, through the microprocessor control means, circuitry is triggered to stop the conveyer means immediately and sound an audible warning, such as a siren and a visual warning such as a flashing red light.

Suitably, after any metal contaminate is removed from the polyethylene material prior to shredding, the conveyer belt is restarted and non-contaminated rolls of polyethylene material are transported into the shredder means which cuts the material roughly into strips typically 10 to 15cm in length.

Preferably loose soil and plant material is removed from the polyethylene material at the shredder.

Preferably the loose soil and plant material waste is stored in a bunded area on the processing^' site. The bunded area is a containment area, usually walled to contain leakage of contaminates to ensure that there is no occurrence of off site movement of the potentially contaminated solid waste.

Preferably after passing through the shredder, the polyethylene material is transported by means of a trough conveyer to the trommel means where further soil and plant material is removed. Trommels are typically large sloping cylindrical cages which rotate so that solid material is shaken loose from the polyethylene material and falls through the perforations of the cage. Preferably the waste from the trommel means falls away from the polyethylene to a lower level and is transported away from the reclaiming plant to be stored in the same bunded area as the waste from the shredder.

The bunded area ensures that no off site movement of potentially contaminated waste occurs and this stage is designed to remove further amounts of contaminants in the form of dirt and organic material from the polyethylene material before further cutting and washing.

On leaving the trommel means, the polyethylene material falls directly into the granulator means. At this stage, dust and other light contaminates are extracted by the use of a large volume blower, cyclone extractor and dust bag.

The waste fraction collected at the dust bag is also stored in the same bunded area at the solid waste from the shredder and the trommel means.

The granulator reduces the polyethylene material to a more manageable size for washing, drying, compacting and further processing.

Preferably the granulator means includes a granulator screen which allows strips of polyethylene material of a suitable size typically 3cm by 1cm to pass through. From the granulator the pieces of polyethylene are blown through a cyclone extractor and the polyethylene material preferably falls directly into the liquid washing means.

Preferably the liquid washing means comprises a clean water storage tank, a filter back flush tank and a back flush water storage tank which is pumped into the liquid washing means through media filtration means.

Preferably, the media filtration means comprises one or more inline sand filtration means comprises of one or more inline sand filters with pressure gauges so that when the pressure reaches a predetermined set point the unit goes into backflush to minimise water use as water used from the back flush storage tank is recycled from the liquid washing means.

More preferably, there are a pair of inline sand filters included in the media filtration means.

This process minimises water use as water used from the back flush storage tank is recycled from the liquid washing means.

Preferably the reclaiming plant has a capacity of 5000 liters and can handle 30 kg of granulated polyethylene material per minute. Preferably the washing means includes an overflow tank as an integral part of the wash plant. The water level is regulated by the overflow water tank.

Preferably the liquid washing means includes a series of rotating paddles to wash and move the polyethylene material through the water wherein a final paddle lifts the polyethylene material over the side of the washing means into the drying trommel means.

The washing process removes the majority of waste that has been more strongly adhered to the PE. This waste is captured by three mechanisms:

1. Waste accumulates in the base of the wash plant. This slurry type material is periodically flushed from the plant and is stored in the same bunded area as waste from the shredder and the trommel means.

2. Waste accumulates in media filtration units that continually filter water from the wash plant. These filtration units are back flushed (cleaned) and the effluent is captured in a backflush storage tank. This effluent is allowed to settle overnight and the slurry is drained to the bunded area.

3. Waste accumulates in the overflow tank, the backflush tank and the backflush water storage tank. This effluent is allowed to settle overnight, and once again, slurry is drained to the bunded area. Suitably solid waste recovered from the polyethylene material is stored for a maximum of a four week period and is tested by independent specialists for potentially known contaminates of herbicides, insecticides and fungicides. If the results of the tests are acceptable, the solid waste is disposed of in a cooperating municipal council landfill. If the tests are not acceptable the stored material will be held on site until contaminate residue levels drop sufficiently to allow for disposal as landfill. If the plant is operational for more than four weeks a new bunded area is established and a separate storage process occurs.

Air water resulting from this stage and previous wash plant stages are handled through a separate wastewater management process to ensure that insecticides, herbicides and fungicides are not released into the environment.

There are preferably two phases of wastewater management:

1. Water is included in the slurry that is drained from the wash plant and the overflow, backflush and backflush water storage tanks. This water is stored in the bunded solids waste area and is treated in a similar fashion to the solid waste as herein described in the solid waste management process. This phase is ongoing while the facility is operational at the site.

2. The used water is disposed of when the plant is shut down at the completion of the reclaiming activity for a specific region. 3. Preferably before release, the used wash water contained in the wash plant and associated tanks, is tested by an independent specialist for insecticides, herbicides and fungicides. If results are acceptable, the used wash water will be released into an evaporation pond on the reclaiming site for evaporation.

If the tests are not acceptable, this water will be stored in a storage tank on site until residue levels drop sufficiently to allow for disposal. If treatment of this water is required, this will occur as appropriate for the contaminate. Suitably, water used for the cleaning of the facility is treated in the same manner as above.

Preferably the drying means comprises a first drying trommel wherein the washed and wet polyethylene material is dried via a stainless steel mesh. Preferably the mesh allows the bulk of water to pass through it and back to the wash plant via an overflow tank.

Preferably the polyethylene material then passes through the trommel which removes the bulk of water that adheres to the washed polyethylene material. The polyethylene material is then blown into a next drying trommel where similarly as the polyethylene material hits the side of the trommel with force this assists with the removal of any excess water adhering to the surface of the polyethylene material. As the polyethylene material moves through this trommel air is jetted into the trommel from a central part that runs the entire length of the trommel. The jets of air further circulate and dry the polyethylene material.

Preferably the hopper means collects the cleaned and dry polyethylene material from the drying trommels and is associated with funnel means to funnel the clean and dry polyethylene material into the compacting and bailing means.

Preferably, when the bailing process is completed, an electronic switch closes off the hopper to enable the polyethylene material to be stored, in the hopper.

The compacted bails of processed polyethylene material are then removed and new bay liners and tie wires are positioned inside the compacting and bailing means and the hopper is then reopened and more clean and dry polyethylene material falls into the compacting and bailing means to repeat the bailing process.

Preferably the reclaiming plant is self powered by the incorporation of an electric generator, typically a 120 kva generator. Preferably the connection means includes power sharing means adapted to allow the sharing of electric supply between processing units.

In another aspect the invention resides in a method of processing horticultural and agricultural polyethylene material by means of the relocatable and transportable reclaiming plant as herein described, the method including the steps of,

1. assembling the plurality of processing modules to comprise the reclaiming plant, 2. conveying the polyethylene material to the shredding means by means of the flat bed conveyer,

3. detecting metal contaminating the polyethylene material by the metal detection means prior to being shredded by shredding means wherein the conveyer is stopped should metal be detected and the metal removed before the conveyer is restarted,

4. conveying the shredded polyethylene via a trough conveyer to trommel means whereby loose soil and plant matter is shaken off and removed,

5. storing the loose soil and plant matter in a bunded area,

6. granulating the polyethylene material in the granulation means where dust and other light contaminates are extracted by a large volume blower, cyclone extractor means and dust bag,

7. storing the waste fraction at the dust bag in the bunded area, 8. washing the granulated polyethylene material through the washing means with water,

9. disposing the slurry settling from the washing means in the bunded area,

10. drying the washed polyethylene material with the drying means, typically twin drying trommels,

11. storing the clean and dry polyethylene material in the hopper means,

12. tunneling the clean and dry polyethylene material from the hopper to the compactor and baling means, wherein compacted bales of polyethylene material are then available for transport to a plastics recycler, 13. on completion of the reclaiming process at a particular site, the reclaiming plant is disassembled for transporting and relocation to another site wherein it is reassembled to repeat the method from step 1.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention be better understood into practical effect, reference will now be made to the accompanying drawing wherein, Figure 1 and 2 show a three dimensional perspective and planned views, respectively of a preferred reclaiming plant of the invention, and

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to figures 1 and 2 there is shown a perspective aerial and plan view of a preferred polyethylene reclaiming plant according to the invention. The portable reclaiming plant 10 is transported to a regional site where it is unloaded and the separate demountable processing units 12-32 are assembled to form the reclaiming plant. When situated in place and fully assembled, the reclaiming site preferably measures 10m by 10m. The reclaiming plant is self- powered preferably by a 120kva generator 40.

The polyethylene material is delivered to the regional processing site directly from surrounding farms in tightly rolled bails approximately 1 cubic meter in volume. These bails or rolls are placed onto the flat conveyer 12 which is normally the first component or processing unit. Above in an overhead position, a fixed metal detector or sensor comprising the metal detection means is activated to locate any pieces of metal contaminating the polyethylene material to processed. If metal is detected, circuitry is triggered to stop the conveyer belt immediately and to sound an audible warning, such as a siren and a visual warning such as a flashing red light. As herein before described, the various processing units are preferably coordinated and controlled by microprocessor control means associated with sensors strategically positioned on the processing units such that the processing can be shut down and restarted in staged order to prevent damage to the units and to control the rate of processing. Typically, these sensors can be infrared beam sensors, pressure sensors adapted to detect air pressure and flow sensors where liquid flow is to be monitored. After the metal contaminate has been removed, the belt is restarted and the non-contaminated rolls of polyethylene fall into the shredding means comprised of a shredder which roughly cuts the material into 10 to 15 cm strips. As it does so, loose soil and plant material is removed the polyethylene material at the shredder. This waste is stored .at a bunded area on the site. The bunded area is an area set aside for the storage of contaminates and is usually a walled area to contain any leakage of the contaminates. This bunded area ensures that no off site movement of potentially contaminated solid waste occurs.

After passing through the shredder, the polyethylene material falls into a trough conveyer that transports it to a trommel where further soil and plant material is removed from the polyethylene. This waste falls away from the polyethylene to a lower level and is transported away from the reclaiming unit to be stored in the same bunded area as waste from the stage 2 process. Again the bunded area ensures that no off site movement of potentially contaminated solid waste does occur. This stage is designed to remove further bulk amounts of contaminates (dirt and organic material) from the polyethylene material before further cutting and washing.

From the trommel, the PE material falls directly into a granulator 20. Dust and other light contaminates are extracted at the granulation process through the use of a large volume blower 22, cyclone and dust bag. This waste fraction is collected at the dust bag and is also stored in the same bunded area as waste from Stage 2 & 3. For the reclaiming process, this vital stage ensures that the material is reduced to a more manageable size for washing, drying, compacting and further processing by the recycler. The granulator's screen only allows strips of material 3 cm x 1 cm to fall through it. From the granulator, the pieces of PE are blown, through to a cyclone and falls directly into the wash plant 24.

The wash plant draws water from a 2 OOOL-storage tank 38, a 1 ,500L filter backflush tank 34 and a 1.500L backflushed water storage tank 34, which is pumped into the plant through media filtration. This process minimizes water use by the facility, as water used from the backflush storage tank has been recycled from the facility. The plant itself has a capacity of 5.000L and can handle 30kg of granulated PE per minute. The water capacity includes an overflow tank 36, which is an integral part of the wash plant. The water level is regulated by the overflow water tank 36. A series of rotating paddles wash and move the material through the water, where the final paddle lifts the PE material over the side of the wash plant into twin drying trommels 26,28.

1. Waste accumulates in the base of the wash plant. This slurry type material is periodically flushed from the plant and is stored in the same bunded area as waste from stages 2, 3 & 4. 2. Waste accumulates in media filtration units that continually filter water from the wash plant. These filtration units are backflushed (cleaned) and the effluent is captured in a backflush storage tank. This effluent is allowed to settle overnight, and once again, slurry is drained to the bunded area.

3. Waste accumulates in the overflow tank, the backflush tank and the backflush water storage tank. This effluent is also allowed to settle overnight, and once again, slurry is drained to the bunded area.

Solid waste is stored based on accumulation for a maximum of four week periods. If the plant is operational for more than four weeks, a new bunded area is established and a separate storage occurs.

Immediately following the four week accumulation process of solid waste, samples are tested by an independent specialist for potential known contaminates of herbicides, insecticides and fungicides. If the results of these tests are acceptable, the solid waste will be disposed of in the cooperating council's landfill. If tests are not acceptable, the stored material will be held on site until residue levels drop sufficiently to allow for disposal. If treatment of the waste is required, this will occur as appropriate for the contaminate.

Water and the PE material from the wash plant enter the first drying trommel via a stainless steel mesh. This mesh allows the bulk of the water to pass through it and then back to the wash plant via the overflow tank 36. The PE material then passes through the trommel 26, which knocks off the bulk of the water that is adhering to it.

All water resulting from this stage and previous wash plant stages are handled through a separate wastewater management process to ensure that insecticides, herbicides and fungicides are not released into the environment.

There are two phases of wastewater management:

1. Water is included in the slurry that is drained from the wash plant and the overflow, backflush and backflush water storage tanks. This water is stored in the bunded solids waste area and is treated with the solid waste as described in the above solid waste management process. This phase is ongoing while the facility is operational at the site,

2. The used water is disposed of when the plant is shut down at the completion of the reclaiming effort for a specific region. a) Before release, the used wash water contained in the wash plant and associated tanks, is tested by an independent specialist for insecticides, herbicides and fungicides. If results are acceptable, the used wash water will be released into an evaporation pond on the reclaiming site for evaporation. b) If tests are not acceptable, this water will be stored in a storage tank on site until residue levels drop sufficiently to allow for disposal. If treatment of this water is required, this will occur as appropriate for the contaminate. c) . Water used for the cleaning of the facility will be treated in the same manner as above.

The PE material is then blown to the next drying trommel 28 in a similar fashion as in stage 4. The PE material hits the side of the trommel with force to help knock off any excess water adhering to its surface. As the PE material moves through this trommel, air is jetted into it from a central pipe that runs the entire length of the trommel. The jets of air further circulate and dry the PE material.

The fully cleaned an dried PE material is then blown into a hopper (via a cyclone) that funnels into a compactor/baler. When the baling process is complete, an electronic switch closes off the hopper so that the PE material can be stored. When the compacted bale is removed and a new bale liner and tie wires positioned inside the baler, the hopper is opened and the stored PE material falls into the compactor/balers thus repeating the process. Finished bales measure 1.2 m x 1.1 m x .9 m and are rolled away to the loading area for transport to the recycler. ADVANTAGES OF THE INVENTION

• The present invention is unique. There are no transportable or relocatable on site reclaiming plants anywhere in the world

• Recycling of horticultural and agricultural polyethylene creates and environment for sustainable business growth, increased market share and the increased adoption of drip irrigation (re-tape) by current and new end users. Therefore recycling provides sustainability for the overall drip irrigation industry.

VARIATIONS It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the area deemed to fall within the broad scope and ambit of the invention as is herein set forth.

Throughout the description and claims this specification the words; "comprise" and variations of that word such as "comprises" and "comprising", are not intended to exclude other additives, components, integers or steps, "bunded area" refers to any area where contaminates are contained,

"trommel" refers to any trommel means comprising a rotatable cylindrical cage for the removal of dirt and plant material.

Claims

1. A transportable and relocatable on site plastics reclaiming plant including a plurality of interdependent demountable processing modules adapted to be assembled together, to comprise the reclaiming plant and wherein the assembly of the processing modules can be disassembled for transport and relocation to other sites.

2. A plastics reclaiming plant as claimed in claim 1 wherein each processing module includes separately or in combination;

conveyer means adapted to convey used polyethylene (PE) material typically drip irrigation tape and mulch to be processed,

shredder means adapted to shred the polyethylene material,

granulation means adapted to granulate the shredded polyethylene material, liquid typically water washing means adapted to wash the granulated polyethylene material,

hopper means for collecting and tunneling the dried granulated polyethylene material,

compacting means for compacting the dried granulated polyethylene material, tunneled from the hopper means,

bailing means for bailing the compacted polyethylene material into bails,

3. A plastics reclaiming plant as claimed in claim 1 wherein there are complementary connection means for assembling together the de-mountable processing units.

4. A plastics reclaiming plant as claimed in claim 1 or claim 2 wherein there is control means adapted to control and coordinate the operation of the processing units when assembled together to comprise the reclaiming plant.

5. A plastics reclaiming plant as claimed in claim 4 wherein the control means is microprocessor control means wherein in operation by detecting the weight or volume of polyethylene material processed by the various processing modules controls the speed of the conveyers and the rate at which the material is processed by the various processing modules.

6. A plastics reclaiming plant as claimed in claim 5 wherein the microprocessor control means receives information from sensors positioned strategically on the various processing modules.

7. A plastics reclaiming plant as claimed in claim 6 wherein there is a sensor placed across the feed hopper of the granulator whereby if the sensor detects a build up of material entering the granulator, it stops the main conveyer, stops the in-feed conveyer and trips the shredder into reverse to await immediate restart in the forward direction; and

when the material clears the sensor, the microprocessor control means restarts the above mentioned units.

8. A plastics reclaiming plant as claimed in claim 6 wherein there is a backpressure sensor for the air blower whereby the sensor can auto-gate the airflow to either the cyclone feed or the surge bin so that it can regulate the air speed required for maximum efficiency.

9. A plastics reclaiming plant as claimed in claim 6 wherein there is a sensor placed, across the out-feed of the drying trommels whereby in the event that the processed polyethylene backs up, all processors prior to the drying trommel stop and allow it to catch up and wherein the microprocessor control means in response to the sensor signal stops the second drying trommel as well as the first drying trommel and also stopped from operating are the wash plant means and the granulator means, and wherein the air blower, the dirt extraction trommel, the main conveyer, the shredder and the in-feed conveyer (or trough conveyer) are kept operating, and wherein when the blockage is cleared, the various processing units stopped from operating are started in the order that they were shut down.

10. A plastics reclaiming plant as claimed in claim 9 wherein there is an overflow sensor on the surge bin wherein the same processing units are stopped when the surge bin overflows.

11. A plastics reclaiming plant as claimed in claim 1 or claim 2 wherein there are flow meters, which control the flow of water entering the wash plant wherein the flow of water in the first drying trommel can be controlled by a flow meter and solenoids that control the main valve, which slows down or increases water flow as required.

12. A plastics reclaiming plant as claimed in claim 11 wherein if an adequate flow can not be achieved all processors prior to the wash plant are shut down and wherein once adequate flow rate is restored, the processing modules are restarted in the following stages wherein the granulator is restarted first, then the dirt extraction trommel, then the main conveyer, then the shredder, and then finally the in-feed conveyer.

13. A plastics reclaiming plant as claimed in claim 6 wherein there is a moisture sensor placed between the out-feed bin of second drying trommel and the surge bin wherein if adequate drying has not been achieved all modules prior to the first drying trommel are shut down and the undried polyethylene material is redirected back to the first drying trommel for additional drying and wherein further drying trommels can be added as required to improve the drying process.

14. A plastics reclaiming plant as claimed in claim 6 wherein there is a sensor placed on the dirt extraction trommel wherein as waste from the dirt extraction trommel exits on the conveyer, it is redirected to undergo a finer screening process to enable the capture of smaller plastic particles which re-enter the process directly at the wash plant stage.

15. A plastics reclaiming plant as claimed in claim 6 wherein, there is a control sensor on the shredder, said sensor to stop feeding material entering the shredder from the feed conveyer, so that there is a time delay between bundles of material entering the shredder.

16. A plastics reclaiming plant as claimed in claim 2 wherein the conveyer means comprises a flat belt conveyer for conveying the unprocessed polyethylene material to the shredder means arid a trough conveyer for conveying the shredded polyethylene material to the trommel means.

17. A plastics reclaiming plant as claimed in claim 2 wherein the conveyer means is a blower and pipe for conveying granulated PE material from the granulation means to the liquid washing means.

18. A plastics reclaiming plant as claimed in claim 2 wherein the metal detection means is an overhead fixed metal detector which is activated when pieces of metal contaminate are present with the polyethylene material to be processed and wherein on detection, through microprocessor control means, circuitry is triggered to stop the conveyer means immediately and sound an audible warning, such as a siren and a visual warning such as a flashing red light.

19. A plastics reclaiming plant as claimed in claim 18 wherein, after any metal contaminate is removed from the polyethylene material prior to shredding, the conveyer belt is restarted and non-contaminated rolls of polyethylene material are transported into the shredder means which cuts the material roughly into strips typically 10 to 15cm in length.

20. A plastics reclaiming plant as claimed in claim 2 wherein any loose soil and plant material is removed from the polyethylene material at the shredder means.

21. A plastics reclaiming plant as claimed in claim 20 wherein the loose soil and plant material waste is stored in a bunded area on the processing site, said bunded area comprising a containment area, said area walled to contain leakage of contaminates to ensure that there is no occurrence of off site movement of the potentially contaminated solid waste.

22. A plastics reclaiming plant as claimed in claim 2 wherein after passing through the shredder, the polyethylene material is transported by means of a trough conveyer to the trommel means where further soil and plant material is removed said trommels comprising large sloping cylindrical cages which rotate such that solid material is shaken loose from the polyethylene material and falls through the perforations of the cage.

23. A plastics reclaiming plant as claimed in claim 22 wherein the waste from the trommel means falls away from the polyethylene to a lower level and is transported away from the reclaiming plant to be stored in the same bunded area as the waste from the shredder.

24. A plastics reclaiming plant as claimed in claim 2 wherein on leaving the trommel means the polyethylene material falls directly into the granulator means, wherein dust and other light contaminates are extracted by the use of a large volume blower, cyclone extractor and dust bag and the waste faction collected at the dust bag is also stored in the same bunded area at the solid waste from the shredder and the trommel means.

25. A plastics reclaiming plant as claimed in claim 2 wherein the granulation means reduces the polyethylene material to a more manageable size for washing, drying, compacting and further processing.

26. A plastics reclaiming plant as claimed in claim 25 wherein the granulation means includes a granulator screen which allows strips of polyethylene material of a suitable size typically 3cm by 1cm to pass through wherein the pieces of polyethylene are then blown through a cyclone extractor and the polyethylene material falls directly into the liquid washing means.

27. A plastics reclaiming plant as claimed in claim 2 wherein the liquid washing means comprises a clean water storage tank, a filter back flush tank and a back flush water storage tank which liquid is pumped into the liquid washing means through media filtration means.

28. A plastics reclaiming plant as claimed in claim 27 wherein the media filtration means comprises of one or more inline sand filters with pressure gauges so that when the pressure reaches a predetermined set point the unit goes into backflush to minimise water use as water used from the back flush storage tank is recycled from the liquid washing means.

29. A plastics reclaiming plant as claimed in claim 1 or 2 wherein the reclaiming plant has a capacity of 5000 liters and can handle 30 kg of granulated polyethylene material per minute.

30. A plastics reclaiming plant as claimed in claim 27 wherein the liquid washing means includes an overflow tank as an integral part of the wash plant and the water level is regulated by the overflow water tank.

31. A plastics reclaiming plant as claimed in claim 2 wherein the liquid washing means includes a series of rotating paddles to wash and move the polyethylene material through the water wherein a final paddle lifts the polyethylene material over the side of the washing means into the drying trommel means.

32. A process for reclaiming polyethylene by use of the plastics reclaiming plant as claimed in claim 1 or 2 wherein the washing process removes most of the waste that is more strongly adhered to the polyethylene, said waste is captured by three mechanisms wherein:

a) waste that accumulates in the base of the wash plant as a slurry type material is periodically flushed from the plant and is stored in the same bunded area as waste from the shredder and the trommel means;

b) waste that accumulates in media filtration units that continually filter water from the wash plant, said filtration units are back flushed (cleaned) and the effluent is captured in a backflush storage tank, and is allowed to settle overnight and the slurry formed is drained to the bunded area;

c) waste that accumulates in the overflow tank, the backflush tank and the backflush water storage tank is allowed to settle overnight, and the slurry formed is drained to the bunded area.

33. A process for reclaiming polyethylene by use of the plastics reclaiming plant as claimed in claim 1 or 2 wherein solid waste recovered from polyethylene material is stored for a maximum of a four week period and is tested for known contaminates of herbicides, insecticides and fungicides wherein if the results of the tests are acceptable, the solid waste is disposed of in a landfill and wherein if the tests are not acceptable the stored material is held on site until contaminate residue levels drop sufficiently to allow for disposal as landfill.

34. A process for reclaiming polyethylene by use of the plastics reclaiming plant as claimed in claim 1 or 2 wherein all water resulting from the process and previous processing are handled through a separate wastewater management systems to ensure that insecticides, herbicides and fungicides are not released into the environment.

35. The process of claim 34 wherein there are two phases of the wastewater management systems inclusive of

a) a first phase wherein water is included in the slurry that is drained from the wash plant and the overflow, backflush and backflush water storage tanks, the water is stored in the bunded solids waste area and is treated in a similar fashion to the solid waste as treated in the solid waste management process as claimed in claim 32 said first phase is ongoing while the facility is operational at the site; b) a second phase wherein the used water is disposed of when the plant is shut down at the completion of the reclaiming activity for a specific region.

36. The process of claim 34 wherein before release, the used wash water contained in the wash plant and associated tanks, is tested by an independent specialist for insecticides, herbicides and fungicides wherein If results are acceptable, the used wash water will be released into an evaporation pond on the reclaiming site for evaporation.

37. The process of claim 36 wherein if the tests are not acceptable the water will be stored in a storage tank on site until residue levels drop sufficiently to allow for disposal and wherein if treatment of this water is required said water will be treated as appropriate for the contaminate.

38. The process of claim 34 wherein water used for the cleaning of the facility is treated in the same manner as in claim 36 or claim 37.

39. A plastics reclaiming plant as claimed in claim 4 wherein the drying means comprises a first drying trommel wherein the washed and wet polyethylene material is dried via a stainless steel mesh and the mesh allows the bulk of water to pass through it and back to the wash plant via an overflow tank.

40. A plastics reclaiming plant as claimed in claim 39 wherein the polyethylene material then passes through a trommel which removes the bulk of water that adheres to the washed polyethylene material.

41. A plastics reclaiming plant as claimed in claim 40 wherein the polyethylene material is then blown into a next drying trommel where similarly as the polyethylene material hits the side of the trommel with force, said force assists with the removal of any excess water adhering to the surface of the polyethylene material and as the polyethylene material moves through the trommel air is jetted into the trommel from a central part that runs the entire length of the trommel whereby the jets of air further circulate and dry the polyethylene material.

42. A plastics reclaiming plant as claimed in claim 1 or claim 2 wherein the hopper means collects the cleaned and dry polyethylene material from the drying trommels and is associated with funnel means to funnel the clean and dry polyethylene material into the compacting and bailing means.

43. A plastics reclaiming plant as claimed in claim 42 wherein after the bailing _x process is completed, an electronic switch closes off the hopper to enable the remaining polyethylene material to be stored, in the hopper.

44. A plastics reclaiming plant as claimed in claim 42 wherein the compacted bails of processed polyethylene material are then removed and new bay liners and tie wires are positioned inside the compacting and bailing means and the hopper is then reopened and more clean and dry polyethylene material falls into the compacting and bailing means to repeat the bailing process.

45. A plastics reclaiming plant as claimed in claim 2 wherein the reclaiming plant is self powered by the incorporation of an electric generator, typically a 120 kva generator.

46. A plastics reclaiming plant as claimed in claim 2 wherein the connection means includes power sharing means adapted to allow the sharing of electric supply between processing units.

47. A method of processing horticultural and agricultural polyethylene (PE) material by means of the relocatable and transportable reclaiming plant as herein claimed and described, the method including the steps of,

a) assembling the plurality of processing modules to comprise the reclaiming plant,

b) conveying the polyethylene material to the shredding means by means of the flat bed conveyer, c) detecting metal contaminating the polyethylene material by the metal detection means prior to being shredded by shredding means wherein the conveyer is stopped should metal be detected and the metal removed before the conveyer is restarted,

d) conveying the shredded polyethylene via a trough conveyer to trommel means whereby loose soil and plant matter is shaken off and removed,

e) storing the loose soil and plant matter in a bunded area,

f) granulating the polyethylene material in the granulation means where dust and other light contaminates are extracted by a large volume blower, cyclone extractor means and dust bag,

g) storing the waste fraction at the dust bag in the bunded area,

h) washing the granulated polyethylene material through the washing means with water,

i) disposing the slurry settling from the washing means in the bunded area, j) drying the washed polyethylene material with the drying means, typically comprising twin drying trommels,

k) storing the clean and dry polyethylene material in the hopper means, (there is nothing after this)

I) tunneling the clean and dry polyethylene material from the hopper to the compactor and baling means, wherein compacted bales of polyethylene material are then available for transport to a plastics recycler, and

m) on completion of the reclaiming process at a particular site, the reclaiming plant is disassembled for transporting and relocation to another site wherein it is reassemble to repeat the method from step 1.