The 7 Steps to Materials Recovery at APR Kerbside Material Recovery Facility (MRF)
How Does Material Recovery Work?
On arrival at APR Kerbside MRF, the collection truck ‘Tips off’ the mixed recyclable materials collected into the loading area.
An excavator or front-end loader is used to put the materials on to the belt. Materials travel up an incline belt and then fed onto conveyors to begin the ‘Pre-Sort’ journey along the line. The conveyors provide a constant feed of commingled material at a steady rate to the plant equipment. They are then separated by a combination of automatic and manual sorting.
At the pre-sort station, non-recyclable materials and contaminants are manually spotted, pulled out and discarded into storage bins below. The greater the number of contaminants in a particular load, the higher the chance that manual sorting will be required. This also results in slowing down the process.
Step 4 - Sorting
The mixed material flowing from the Pre-Sort station moves along the conveyor for Trommel sorting. This process involves separating materials via passing through a large perforated rotating cylindrical drum that has the capability to sort by size. The holes act as a classifier, allowing only material smaller than the hole to fall through. The rest flow out the other end of the trommel and onto the conveyor belt.
Larger pieces of cardboard are removed from the commingled stream. They get pushed to the top by large sorting discs turning on axels, meanwhile heavier materials stay beneath.
Smaller sized sorting discs are then used to remove smaller pieces of paper. During separation, materials are diverted to separate conveyors for gathering and baling.
Step 5 - Sorting
Electromagnets (a powerful magnetic separator) are used to remove steel and tin cans by automatically transferring them to a storage bin.
To extract the aluminium cans, a (electromagnetic field) referred to as an Eddy Current separator is used to draw out the cans and other non-ferrous metals from the remaining commingled material. The cans are then stored in another bin.
Using conveyors and disc screens, materials are further processed with sophisticated automatic recognition. This method is called Optical identification whereby separation occurs by use of air jets and infrared sensors. Plastics are identified and can then be removed by manual sorters who separate according to plastic number codes.
Separated materials are compressed and baled, ready to be efficiently transported to different processing facilities. They can be re-made into new products and recycled packaging through local manufacturers.
The benefits of having a 4-bin system and no glass in the kerbside commingled recyclable stream means the quality of the processed end product is significantly improved.