Properly differentiating urban solid waste - separating it according to the indications provided by the local Municipality and disposing of it in the appropriate waste disposal areas or taking advantage of the doorstep collection service - is the first step in allowing it to be correctly treated and recycled into new materials.
Promoting differentiated waste collection and studying forms of information and incentives to help citizens do it correctly is crucial, but it is not enough to solve the problem of waste treatment at its root. Once the collection is complete, waste cannot be sent indiscriminately to companies that produce goods from recycled materials, but must be treated in special waste selection plants that separate the materials present in the waste bags and send them to the next stages of treatment and recovery.
The waste selection plants for recycling are designed in a customized way and are sized based on the needs of the individual waste disposal center. The amount of waste to be treated per hour and the number of people employed in the plant can modify the organization of the plant, and there are some differences between plants designed to collect non-differentiated waste and plants that deal with "cleaning" waste already coming from differentiated collection, to correct any errors and avoid - for example - mixing plastic residues with paper or glass destined for recycling.
If waste selection plants can be of various types, their general structure is always similar, and is based on the presence of a conveyor belt that collects the materials and accompanies them throughout the differentiation process.
In the case of Camec's waste separation and grinding plants, this conveyor belt is generally installed at floor level, to facilitate loading procedures and simplify the start of waste separation. Once loaded onto the conveyor belt, the waste is sent to a lacerator or an opener that, thanks to the presence of special blades, allows breaking the bags containing the waste and obtaining a mass of unpackaged waste, ready for selection.
The unpackaged waste is then sent to a second conveyor belt. In Camec's waste separation plants, the passage from one conveyor belt to the next is regulated based on various parameters, depending on the quantity and type of material being processed, to avoid accumulations and allow for ideal material treatment. The waste is then sent to the next stages of separation, which can be automated (e.g. using magnetic separators that extract the ferrous components of the waste) or manual. In the case of manual separation, the conveyor belt rises to reach a sorting platform where the operators are located to remove specific materials from the waste, collecting them and making them fall into the containers placed below the conveyor belt. These containers, once full, are emptied, their contents are compacted and then sent to specialized recycling centers for the treatment of individual materials.
At the end of the process, the remaining undifferentiated waste is collected and sent to further treatments, incineration plants or landfills.
The waste selection process allows for a significant increase in the quantity of waste sent to correct recycling. This makes it possible to obtain larger quantities of reusable materials, ready to be recycled and resold, and at the same time to reduce the environmental impact of waste, ensuring that each individual fraction of paper, plastic or glass extracted from the undifferentiated waste is truly "clean" and does not contain traces of materials that could make the recycling process less effective.
This activity also allows for the separation and elimination of potentially hazardous or special waste that may have been incorrectly disposed of among urban solid waste, avoiding the risk of it being sent to landfills or incinerators and releasing pollutants into the atmosphere.
The waste selection plants therefore allow for the protection of the environment and human health, the reduction of CO2 emissions, the creation of virtuous mechanisms based on recovery and recycling, and the reduction of waste of primary resources, making it possible to introduce high-quality secondary raw materials into the market.