NEW LIFE FOR SOLID TIRES
From end-of-life solid tires for cranes and forklifts come new eco-friendly products for industrial and agricultural use. An innovative company based near Cremona calls for more solid tires to recycle
Milan, piazza della Scala. A girl taking a selfie in front of the world’s most famous opera theatre, while a yellow tram, one of those that has been used by Milan’s residents for over 85 years, goes by. The scene repeats itself over and over again every day, yet no one realizes that many of the items portrayed in that picture use materials coming from end-of-life solid tires. Difficult to imagine if you’re not an insider. At times the material is not clearly visible, being covered underneath other structures, but many would also erroneously assume that the shoes worn by the girl have rubber soles or that the flowerbed in the picture has a mulch groundcover (to prevent the growth of weeds).
But let us take a step back in order to solve the mystery. When we think at what can be done using end-of-life tires, we tend to think in terms of normal tires and not solid ones, the kind used in the industrial handling sector (mobile cranes, forklifts etc.). These tires are retreaded several times and contain high amounts of precious natural rubber making them very elastic. By recycling it, many other products can be made, such as rubber soles, groundcover material, anti-vibration boards used on railways and tram lines, thermal insulating and sound absorbing panels used in the construction industry. If we think that this material was also used during the renovation of the Teatro della Scala itself, we understand how many times it appears in the selfie taken in Piazza della Scala.
The solid tires market is rather small when compared to normal tubeless tires, though capable of producing a considerable amount of ELTs. For this reason, few companies recycle them. One such company operates in Italy, it is called E-Cova and is based near Cremona, where it started as a retreading company specializing in super-elastic and cushion tires. The idea came following a government decree, known as “Decreto Ronchi”, which marked an important milestone towards correct waste disposal. Up until roughly fifteen years ago, Cova Claudio & Sons would also regularly send the waste produced through its activity to a local landfill, such as casings that were no longer retreadable and waste produced through buffering processes. Some of this waste is made up of steel wires and fabric, but a lot of rubber is also to be found that could be re-used, as mentioned above, or for less demanding applications such as hand trolleys or hand pallet trucks.
The idea of recovering rubber from solid tires came from observing the buffing of wheels before retreading: an operation similar to turning, in which the wheel is spun and a rotating cutting tool removes the tread. Over the years, this idea has been improved and E-Cova’s technicians have patented a machine that looks very different from a normal buffing machines, with higher productivity (in the current AT22110 model, the cycle is fully automated, manual operations are limited to loading and unloading, and an operator can handle two machines at the same time) and a specific work cycle for the recycling of materials; the basic idea, however, is always the same. For this reason tires that cannot be keyed and spun, such as those that are torn or cut, cannot be recycled.
After being mounted, the wheel gets turned until the cutting tool finds the steel structure; here the buffing stops automatically so as not to spoil the rubber powder and mulch. Following this operation, sifters divide the resulting materials according to size, which are than stocked into big bags ready to be dispatched. Some days are dedicated to recycling rubber trolley wheels, extensively used in food stores and for pharmaceutical products.
A container filled with rubber is what comes out of E-Cova. Their job ends here: from this moment, it’s the customers’ responsibility, almost all from Northern Europe, to turn this secondary raw material in everyday objects. Rubber soles, as well as new wheels or mats, are made from the rubber dust. The smaller size frayed rubber is used for the flooring of nursery schools and gyms and for anti-vibration boards; the larger size for thermal insulating and sound-absorbing boards used in construction. A fourth largest size goes to form material for mulching, which is often dyed in colors that makes it resemble bark. Compared to which, however, rubber has a great advantage: it does not rot or breed fungi and plant pests. This same size is used as anti-shock flooring for outdoor sports facilities, such as structures dedicated to parkour, a urban discipline based on an obstacle course.
Tires initially are collected only through the network of sales and service of Cova Claudio & Sons, extended to all of North Italy and Tuscany. Their associates deliver to the customer (tire dealers or rental fleet) the new tire, already mounted on a rim provided by Cova (they manufacture wheels as well) and withdraw the ELTs a few days after that. Nowadays the flow of casings is continuous, but not enough to supply the demand of companies that transform waste rubber. That’s why E-Cova acquires material from tire dealers and operators throughout Italy but also from France. A fraction of this is made up of solid tires, E-Cova’s bread and butter.
Recycling solves another problem: solid tires cannot count on government scraping incentives for end-of-life tires as the norm provides only for tubeless tires, namely, tires containing pressurized air; solid tires, not having those characteristics, are out of the legislative requirements and therefore would represent an additional cost for the tire dealer. Thus, a virtuous circle is closed, one that preserves the environment and reduces costs. Is it all right, then? In principle, yes, even if (as highlighted by the box below "A production chain that could work better"), this innovative and environmentally friendly idea is living a paradoxical situation: lack of waste to be recycled, just when many solid tires are still disposed of by less virtuous methods.
Half a century of tires
The Cova family’s first company was founded in 1967 for retreading both car and truck tires, which will remain the core business until the mid eighties to be followed later by the trade of solid tires (super-elastic, elastic, cushion tires and pallet truck wheels and rollers) for industrial handling. In 1985 retreading also reached this sector, which will prevail, in recent years, over the traditional retreading business. All happening internally, as proudly emphasized by the "100% Cova" logo.
In 1995 the workshop that manages, builds and repairs tire rims was set up as the base of a Re-turn service, providing the customer with new or retreaded tires already mounted on wheels identical to the vehicles’ original equipment. The mounting operations are then cared for by Cova, with a considerable saving of time for the tire dealer. Brand new rims are also produced in the workshop, both for the aftermarket and original equipment: several manufacturers choose Cova to equip their cranes and forklifts. Since 2000, the company has been manufacturing and developing its first buffing machines specifically designed and dedicated to the recycling of rubber. In ten years the business has grown considerably, until the founding of E-Cova (2011) that specializes in this sector.
The two companies are currently managed by Raffaella and Gabriele Cova, the founder’s son and daughter. Retreading and recycling over three shifts, with the factory fully operational for 24 hours. During 2013, goods for over 1.100 tons were produced.
A production chain that could work better
End-of-life solid tires have the waste code ERC (160 103) and according to the European Directive 1999/31 EC, can no longer be taken to landfills but should be recycled. Paradoxical, therefore, that the only great difficulty today is the availability of raw material. For many tire dealers, forklifts represent a sideline business, therefore they do not think of disposing the few solid tires separately from normal tubeless tires. Nor are they aware of the difference in the recycling chains. There is yet another problem: low-cost tires from Asia have very little super-elastic rubber, often replaced by textile materials. These, in addition to not guaranteeing a correct damping, contaminate rubber powder and frayed rubber. E-Cova is constantly looking for new partners and associates, especially in areas still not covered by the Cova Claudio & Sons’ network, to supply a greater number of end-of-life solid tires.