Agglomeration with WiPa Plast Compactor

The WiPa Plast Compactor Type PC is an agglomerator for gentle densification of plastics with low bulk density, for example:

- fibres - film – stretch film – foamed materials – powder – fine particles

During the process the WiPa Plast Compactor transforms the low bulk density plastic into an easy-dosable agglomerate with high bulk density, with lowest possible thermal damage.

 

The Process

A feeding system transports shredded plastic to a buffer container. An agitator in the buffer container guarantees permanent filling of the feeding screw and prevents bridging. The feeding screw pre-compacts the plastic to be recycled and feeds it to the Plast Compactor’s disc pair. The disc pair consists of a moving rotor disc and a non-rotating stator disc serving as counter element. Kneading and rolling between the discs creates friction heat and plastifies, sinters and compresses the material. The process is 100% PLC controlled and needs only a few operators to feed the machines with material.

Gentle densification

The thermal impact on the material in WiPa Plast compactor can be hardly compared to the conventional agglomerators, which work in a batch process or standard extruders, because the dwell time of the material in the machine is only a matter of seconds. In this process step the melting point is not reached, because the material is only being transformed into a pasty condition and leaves the discs at its own volition.

The Agglomerate

During the process finger size agglomerates are created which are cut to the desired grain size by means of a granulator installed downstream. The size of the agglomerates is determined by the screen installed in the granulator. To cool the material down and avoid dust as well as fines accumulation in the final product, the agglomerate passes through an air sifting unit after the granulator and before conveying to a silo or big bags.

Agglomeration and Drying

The WiPa Plast Compactor is mainly used to increase the bulk density of plastic materials. Nevertheless, there are several other fields of application: For example, efficient drying of plastics being processed in a washing line. During the process the material gets heated, moisture evaporates, so that final humidity content is reduced up to less than 0,5%. In this condition the material is prepared for further processing in an extruder or an injection moulding machine.

Compounding

Additives and fillers like color pigments, plasticizers, etc. can be fed via special dosing units directly into the feeding screw of the Plast Compactor. The material is being warmed in the compacting zone until the fillers have been absorbed.

 

 

Crystallization of PET flakes

Crystallization of PET flakes after a hot washing process is also a possible task for the WiPa Plast Compactor. The material gets warmed till it reaches a pasty condition what aligns the molecules. Crystallization of the PET starts with temperature of 80°C, which is fast and easily reached by a WiPa PC. The viscosity (IV) remains almost unchanged, because during the process the melt point is not reached.

 

Type PC

PC

150

300

500

600

700

850

1400

Main drive kW

kW

15-45

30-75

75-160

110-200

160-315

315-630

400-1000

 

 

 

 

 

 

 

 

 

Bulk Density

g/l

 

 

 

 

 

 

 

Throughput rate

 

kg/h

kg/h

kg/h

kg/h

kg/h

kg/h

kg/h

HDPE

370

80-150

280-350

480-700

750-1200

1150-2000

1700-3000

2500-4000

PE film

350

60-130

200-500

500-800

750-1150

800-1600

1200-2100

2000-3500

PE foam

350

50-120

200-500

400-700

700-1050

750-1400

1000-1650

2000-3200

PP non woven

390

60-120

150-300

400-700

700-1250

750-1400

1050-1850

2000-3100

PS film

460

60-120

150-300

300-700

700-1200

750-1300

1100-1900

2150-3250

EPS

500

70-125

180-300

300-700

700-1200

750-1200

1000-1600

1900-2700

PVC film

600

90-160

250-400

300-700

750-1250

800-1500

1150-1850

2100-3100

PVC foam

500

80-140

250-400

300-700

700-1200

800-1450

1000-1650

1850-2700

PET film

600

90-150

200-300

600-900

750-1350

800-1700

1150-2150

2100-3400

PET fibers

600

85-140

150-300

400-600

750-1100

850-1450

1200-1750

2000-2600

PET foam

550

80-130

100-250

250-600

550-1000

650-1100

1000-1550

1700-2400

PET fleece

600

90-150

200-350

400-700

650-1250

800-1750

1100-2150

1800-2600

PET flakes (bottle)

550

100-160

200-400

400-1000

700-1300

950-1800

1380-2200

2400-3900

PA film

430

80-130

150-300

400-900

650-1250

850-1650

1200-2100

2150-3400

PA 6 / 6.6 fibers

450

80-120

150-250

400-900

650-1050

800-1250

1000-1700

2000-3200

Carpet waste

390

70-120

100-250

350-600

600-1000

800-1200

1000-1600

1900-2900

Synthetic Rubber

420

90-140

150-400

250-700

650-1500

800-1850

1100-2200

2100- 3200

Wood plastic

350

90-120

150-350

250-600

650-1350

800-1650

1000-1900

2000-3000

Videos