With the term recycling, we refer to the entire complex and lengthy process that starts from the separation of materials and leads to giving new life to an object, a material, or anything else that, after being used, is recycled and regenerated to become something new.
And as we have already said, it is something extraordinary.
The glass I am drinking from right now will become the bottle I will find on the kitchen table tomorrow, and maybe the day after tomorrow, it will turn into the chandelier or the mirror at home, and all this can happen with many other objects that surround us in our daily lives.
All of this is part of the complex ecosystem called recycling and regeneration of materials, which in turn includes various processing stages that are necessary to achieve the final goal.
The first process from which everything starts is the collection of materials that are considered end-of-life. This operation must be carried out correctly and separately to group together all those objects that, in the recycling process, need to be compatible.
It goes without saying that the process of collection and separation of materials, the more carefully and precisely it is carried out, the easier it becomes to facilitate the subsequent processing stages, improving and simplifying all processing phases.
Those who do not live or work in this sector might think that today’s technology is so advanced that in recycling plants, you just press a button, and at the end of all the material separation processes, we find many nice piles of products divided by type, color, specific weight, etc., etc.
Well, things don’t quite work like that, and despite the great strides made by technology in recent decades, the percentage of material separation will never be 100%.
This happens for various reasons, which we have already extensively discussed in detail in our previous article in the “Value” section, and one of the main reasons is certainly linked to the shape and physical composition of the objects themselves.
Let us try to explain better:
Let’s take, for example, a common household object, the iron, but the same concept could also apply to many other objects around us.
This is made up of plastic or rubber parts, such as the handle and casing, steel parts, such as the soleplate, and copper parts that are found inside, including the heating element, electrical wires, and contacts.
So we see how, in an object of relatively small dimensions, we find at least 4 or more types of materials, which in turn include subcategories. For example, the insulating part of the cables and contacts will surely be composed of various types of plastic materials such as PVC, insulating foams, rubber, and perhaps others.
So, going into detail, we realize that from a single object, if we wanted to dismantle it to separate each of its elements by material type, we would certainly obtain 10 or more different materials.
Clearly, such a detailed separation of materials in a single processing phase is not something that today’s technology, although more advanced than in the past, can yet achieve. Therefore, we must “settle” for a separation carried out by macro categories; so, in the case of the iron, for example, it is possible to separate the metal parts from the plastic parts during the first rough sorting, and then separate magnetic metals from non-magnetic metals, thus obtaining steel and copper. As for the plastics, if there is a difference in specific weight, it will also be possible to separate rubber from plastic.
Let’s also think, for example, of the case of copper – plastic separation.
We can see how this double step already allows us to recover a good percentage of the iron we want to recycle.
It immediately becomes clear that if we were to make a mistake and throw a glass bottle along with the iron, even though it is made of a 100% recyclable material, it would be considered a contaminant and a major problem, as it would enter a separation line where glass is not expected, making it difficult to manage.
This highlights how the collection and initial sorting phase is truly important and must be carried out with great care and a sense of responsibility.
But let’s go back for a moment.
How do we separate metals and plastics from the iron? Do we have to dismantle each part and divide it?
SEPARATION AND RECOVERY OF METALS
To facilitate the process of metal separation and recovery, in general, when dealing with composite objects made up of multiple parts of different materials, the first processing step is shredding.
The only way to separate metals from an object containing many other materials is to release everything inside it by grinding it. By passing through a mill, it is broken into many smaller parts, depending on the size of the original object.
And once we have our pile of shredded pieces, what should we do?
From this point on, the vast and complex world of metal separation from other materials comes into play.
For each type of material to be separated, processes, operations, and machines are applied that evaluate the physical aspects of the material—shape, weight, color, etc.—in order to extract and separate it from everything else.
To help you better understand without going into the technical specifics of each separation operation, imagine that all the pieces crushed by the mill can be compared to a group of people of the same height and age. From a distance, they may all look the same, but if we get closer and look carefully, we notice differences.
Some have blue eyes, others have beards, others have short hair—these are individual characteristics that differentiate some people from others.
This is the concept of separation: identifying common characteristics of a particular material you want to separate that uniquely define that material from all the rest, allowing it to be isolated, separated, and recovered.
So, going back to our pile of pieces, to separate them, we need to find those unique characteristics that identify that type of material or family of materials.
For example, among metals, we can identify magnetic from non-magnetic ones, thus creating an initial separation. (with a magnetic separator, this type of separation is possible)
Among the non-magnetic metals, we can distinguish light from heavy ones; aluminum alloys weigh much less than all other metals, and in this case, we can create another separation. (using a densimetric separator, these materials can be separated)
By combining different technologies, we have seen how from our iron it is possible to start separating three types of metals: ferrous magnetic metals, light metals such as aluminum alloys, and heavy metals, which are generally copper alloys.
This concept applies to all materials—metals, plastics, glass, compost, etc. A unique property of a component is identified, and the technology is adapted to separate it from everything else.
To see our plants in action, visit the Video section on our YouTube channel:
– Video fine metal recovery
– Video densimetric separator
SEPARATION AND RECOVERY OF COMPOST
And how does the process of compost separation and recovery work? First of all, what are they: Compost or Humus are commonly identified as bagged soil.
The process of producing compost is quite complex and involves the world of biochemistry. Through specific enzymes and bacteria that work at certain temperatures, humidity levels, etc., plant material transforms into compost.
Said like this, it is quite simplified. In reality, the whole process is much longer and more complex, but what interests us is the end of the process, that moment when the entire mass of plant material has turned into compost, and within it, we find materials that should not be present in the bag of soil we buy at the supermarket.
At this precise moment, the fascinating world of material separation comes into play, which will separate the compost from all those “impurities” present in the final stage of its decomposition process.
Clearly, someone buying a bag of compost does not want it to contain stones, bones, shells, glass, large pieces of wood, or worse, metals or plastics, which unfortunately are often present.
In this case as well, Ghirarduzzi has developed densimetric and aeraulic separators capable of separating the vegetable fiber from everything considered a contaminant, thus improving the properties and quality of the compost.
To see our systems in action, visit the Video on our YouTube channel:
– Video compost densimetric separator
We can conclude this insight by saying that whenever we throw any object into the designated disposal area, a complex process of steps and operations begins, which, as we have seen, aims to separate as much as possible each material it is made of.
All of this has limitations that are linked to technology and the variability of many external factors. The challenge to improve this every day is ongoing, and companies, universities, and researchers are working hard to constantly enhance these processes.
Everything we can do to make this challenge a bit easier lies in the responsibility we have to commit and learn to separate things correctly.
Now that you have a clearer understanding of everything behind this world, please, don’t throw the glass bottle together with the iron. By doing so, you will have given all of us a great help in properly separating materials.