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Libroplantasingl

for final storage and subsequent transport in order to comply with the requirements of the Technical Specifications for Recovered Materials (TSRM) of Ecoembes. A single properly sized press can bale the output of all selected materials (PET, HDPE, FILM, beverage cartons and mixed plastics) except metals, and particularly steel, which require different bale sizes and features as well as specific presses. Rejected waste management at the facility All sorting facility rejects are typically concentrated on a single output conveyor belt that discharges them at the evacuation point. Occasionally the fine materials current is discharged at different points from other rejected waste. Due to the low density of the rejected waste material, its volume needs to be adapted for an efficient disposal to the landfill. This can involve several alternative systems: • Self-compacters. • Static compacters. • Rejected waste press. • Containers (for low-volume facilities). Transport of containers with rejects is performed using container vehicles to take them to processing sites (dumping LIGHT WEIGHT PACKAGING SORTING PLANTS 30-31 or energy recovery). Quality control Due to errors occurring in the different types of equipment, the selected packaging material contain impurities that reduce the purity of the final product. These impurities are removed through manual sorting. This operation is usually performed after the sorting of each of the recovered materials (PET, HDPE, beverage cartons and mixed plastics) before storing in silos for compaction. In other facilities the quality control is performed before compaction, so that a single operator can perform the operation. The sorted impurities are sent to the rejected waste stream at the facility or, if they are requested materials, recirculated to previous points of the process for sorting. Temporary storage of selected materials The selected materials are deposited in specific confined spaces for each one (intermediate storage silos) awaiting compaction operations. Storage silos are compartments sized according to the following parameters: • Apparent density of each material • Production of each selected material per shift • Hourly capacity of the compacting press. The extraction of the materials stored in the silos is performed using moving bases, conveyor belts or directly with a loading shovel, which evacuate them to the feeder of the baling press placed downstream. If the selected amount of any material is small (e.g. aluminium) the production is stored in auxiliary containers for subsequent compaction. Compaction of selected materials Materials stored temporarily in the containers are subsequently subjected to density increasing operations using baling presses, which produce bales with a density suitable


Libroplantasingl
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