Needless to say, the production of cars today is extremely high. At the same time, every years millions of cars are getting worn out to the extent when they are no longer used. Many unwanted tires are coming exactly from this source, however, it is obvious that tires should be changed several times through the lifespan of a car.
Sometimes old tires are just unwanted and thus, are thrown away, although in many cases, tires can just reach their end of life. Experts regard tires which cannot be re-grooved any more or re-treaded as completely worn-out. This mean, they are not functional for usage. Of course, in some cases tires can get severely damaged so that no repairmen is taken place.
If you are interested what are the possibilities of recycling tires, you will find answers to your questions in this article.
A bit of history of tire recycling
Modern drivers are not even aware of the fact tires used to be a very valuable good a long time ago. Approximately a hundred years ago, tires were not thrown away in the wilderness and their recycling was very crucial. There were several reasons for that. One of them was the fact that there was a time when rubber was extremely valuable. Its price was almost as high as the price of silver.
Needless to say, today tires are a way cheaper. The synthetic rubber used for the production of modern tires is made of cheap oil. In addition to it, the technology of production radial tires with steel belts made them a way cheaper. As a result, from the economic point of view, recycling tires is not thus urgent any more. Furthermore, the process of recycling of such tires became more complicated than it used to be.
What is happening with unwanted tires today?
Unfortunately, many people dump their worn-out tires on landfills which is a rather bad practice. Actually, the shape of tires is making them a perfect shelter for various animals, especially rodents. Furthermore, water can be collected in tires making them a perfect place for mosquito breeding. It is still not the end of the negative impact of old tires lying on the landfills.
Tires are just bulky taking a lot of space. In some landfills, they can even take up to 75% of airspace which is really a lot. Moreover, tires can also trap methane gas. This can make them rise taking them to the surface. In many cases, this causes the rapture of the landfill liners. As a result, the contaminants from such landfills are getting inside the groundwater making it polluted.
Beyond a shadow of a doubt, it is crucial to recycle old tires. Fortunately, the tire recycling industry is developing successfully shrinking the stockpiles of worn-out tires. Thus, in 1991, there was over a billion of old tires stocked whereas in 2017 the number was reduced to 60 million.
What are the options for recycling old tires?
You might have already come across one of the popular forms of tire recycling which is rubberised asphalt or other ground applications of rubber, for instance, on playgrounds. Actually, this is not even the most frequent usage of recycled rubber. The major way of applying such a material is for fuel. Another option is civil engineering applications.
TDF – Tire Derived Fuel
Tire derived fuel is a major option for recycling old tires. Old tires can be a good substitute to fossil fuels under the conditions there are appropriate regulatory controls. This way of reusing tires is quite popular and, in 2018, 46% of old tires were used for fuel production.
It turns out that tires are a better source of energy than coal. Burning this material gives an equal amount of energy than oil burning. This is 25% more than the amount of energy released by coal burning. Furthermore, some types of coal have more heavy metals than tires. Finally, tires release less NOx gases than many types of coal especially the ones high in sulphur.
Today, the tire recycling industry is using two types of tire burning. The first one is burning the whole tires whereas the second one is using tires in their shredded form.
Ground rubber applications
You might have already been at playgrounds or sports fields with synthetic underlay. This one is produced from old tires. Actually, this is only one of the possible ground applications of rubber recovered from old tires. Asphalt, tracks, animal beddings and many more underlays are made of recycled rubber. The major application is the production of rubberised asphalt. Around 12 million tires or 220 million pounds of this material is used for producing asphalt.
25% of scrap tires were used for ground applications in 2017.
Civil engineering applications
The usage of old tires in civil engineering applications is not particularly high yet. For The USA, 8% of old tires were used for this purpose. In this case, recovered rubber is used instead of insulation blocks which are widely made of polystyrene. Another popular usage of old tires in civil engineering is drainage aggregate.