Donaldson Australasia have engineered a waste handling loop solution for Good Impressions. Visy Recycling are involved in the loop as the end recipient of compacted raw material for their paper/cardboard recycling plant in Smithfield, Sydney.
According to Good Impressions, they are involved in recycling the leftover product that goes through their production department. The leftover product is collected by the offcut handling system and Visy Recycling, as the end-recipient in Good Impressions’ recycling loop use the waste to prepare recycled paper and cardboard.
According to Donaldson Australasia, one of the peculiarities of this particular installation is that the waste output from two automated guillotines is channelled separately from the rest of the system.
Paper waste from these guillotines demands a ducted air flow system to be efficient for the client, so here it uses a conveyor belt and gravity to take waste straight into the compacting area.
The majority of paper strips and offcuts on the Good Impressions production lines is collected by suction at operating points and carried through a ducting system suspended from the ceiling. This ends up at the compaction area.
Donaldson Australasia had to meet the following objectives when designing the new paper waste disposal system:
- To improve on waste management system
- To improve on preventive maintenance, e.g. labour cost in housekeeping
- To meet the EPA requirement (Dust emission to atmosphere)
The solution devised offered extraction and separation of paper trim waste where an air/ paper separation device used is a separator that benefits handling. A separator was chosen over a cyclone because it has an inclined baffle plate, situated within an expansion chamber, to knock extracted product out of the air stream rather than relying on a cyclone’s geometry to cut a specific portion of product by centrifuge and internal vortex.
The system is compact and has low energy consumption. The newly installed system extracts paper trim and dust from the following machines:
- One saddle stitcher
- three folders
- two future folders
- two guillotines
Paper trims generated by the machines are conveyed through a balance ductwork to a main trim fan, and then transported to the separator where strip is separated and returned through a chute into the compactor. Air and dust is then transported through the dust collector where the dust is separated from the airstream and an air emission of <15mg/m³ can be expected. Offcuts generated by the guillotines are separately conveyed through an inclined conveyor, which discharges directly into the compactor.
According to Donaldson Australasia, an important aspect of the design of this waste handling system was to make sure that conservative materials handling principles were followed to eliminate material fallout that leads to duct blockage, problems such as insufficient capture velocity and potential for the discharge system to choke, due to positive pressure in the compactor.
Donaldson Australasia observe that these problems were taken into account at the design stage and installation was designed to operate continuously. The equipment is also sized for heavy-duty operation and reliability. During operation, waste is captured from the machine by means of suction hoods of aerodynamic design, specially fabricated in steel welded construction. A saddle stitcher was supplied with its extraction hood, while each folder is connected to an extraction hood. A hopper is fitted on top of the conveyor for collecting the waste from both guillotines.
To conserve materials and costs, guillotines were arranged side by side, so only one conveyor is required between the two machines. Location of these guillotines is close to the building wall which has the compactor located on the other side of it. Donaldson Australasia note that captured waste is conveyed through an aerodynamically balanced piping network made of galvanised steel.
The purpose of this network was to convey waste from the machines through the fan where designated material is then separated from the airstream through the separator. Remaining material is then conveyed to the dust collector where final removal of the particulate from the airstream takes place. A trim fan takes charge of the air capacity and the necessary pressure to transport the waste from the various inlets to the separator. A recovery fan extracts dust and air from the separator through a pollution control system.
The next stage of handling involves installation of an air material separator on top of the compactor. A duct connected to the separator through a transition piece allows a suitable air velocity at the entrance of the separator. Following the separator, a Donaldson DCE Dalamatic DLM 1/5/15 dust collector takes over. This unit uses a reverse pulse jet cleaned fabric filter with a total filter area of 75m². It is also equipped with rear explosion and full antistatic provisions.
Dust collected in the hopper is discharged into one 80 litre bin. The discharge equipment has been selected and sized to minimise risk of blockages and maintenance. To maintain proper environmental control levels and employee safety the trim fan is fitted with inlet/outlet silencers and the dust collector with an outlet silencer to limit the noise level to 85dB (A) at 1 m.