In 2022, some experts predict that China's car ownership will exceed 400 million, and the number of scrapped cars will reach 1 million every year. The production of auto parts is even more astronomical. Among them, the production of tyres has reached an astonishing 780 million, because tyres are a consumable for automobiles. Tires will be replaced if they are worn seriously, so we will produce a large number of tires every year.

How many of these discarded tires are there? We refer to the survey statistics of chemical industry of a university in 2021. In 2021, there will be 330 million scrap tires in China, with a total weight of 22 million tons. These scrap tires have become a long-standing social problem.

How did the waste tires change from "black pollution" to "black gold"?

1. Capacity expansion and price rise

Pollution turned into "gold" in the past

Waste tires and waste plastics were once called "black pollution" and "white pollution". It is a kind of non degradable solid waste containing heavy metal elements; At the same time, stacked tires are easy to cause fires, which are difficult to control and extinguish once they are ignited, and will also produce smoke and toxic oily pollutants, which will affect the environment.

With the development of technology and the enhancement of people's awareness of energy conservation and environmental protection, the industry of comprehensive utilization of waste tires has received more and more attention from the market. Many countries have formed a relatively mature waste tire recycling system, and the capacity of related industries is also expanding. On October 5, the German Prum Innovation Company announced that it would build two more thermal cracking production lines; The Swedish Scandinavian Inviro Systems Company announced that it would build 30 waste tire recycling plants by 2030; Bridgestone, a Japanese tire manufacturer, also announced that it has formulated a plan for the reuse of waste tires. The goal is to build a production line with an annual output of 100000 tons of waste tires from 2027 to 2030, and to achieve the commercialization of waste tire recycling after 2030.

At the same time, the purchase price of domestic waste tires is also rising. According to statistics, on October 20, the price of waste steel wire tyres over 9.00 inches in some parts of China exceeded 2000 yuan/ton, nearly double that of 2020. Once "black pollution" seems to be turning into "black gold".

2. Mature technology resource requirements

 

 

Increased popularity of recycled rubber industry

As solid waste, what is the recycling value of waste tires? Why did the purchase price go up all the way?

According to China Rubber Industry Association, part of the reason for the rise in the price of waste tires is the continued high price of major international raw materials. According to statistics, in 2021, China's natural rubber output will be 851000 tons, while the demand will be 5949000 tons, nearly 7 times the output. The self-sufficiency rate is seriously insufficient. At the same time, with the rise in the price of upstream coal tar and other raw materials, the domestic carbon black price has also risen in recent years. From January to December 2021, the carbon black price has increased by nearly 20%; As of October 27 this year, the average price of carbon black in the national mainstream market was RMB 11700 per ton, up 22.5% from the quotation at the beginning of the year. In the case of high prices of natural rubber and carbon black, many manufacturers will take measures to add renewable materials to reduce costs, and 70% of the total amount of renewable rubber raw materials in China comes from waste automobile tires.

It is understood that the production of recycled rubber is a mature and widely used way to deal with waste tires. After the recovery of metal resources such as steel wire, waste tires will go through the process of crushing, regeneration (desulfurization) and refining to be made into recycled rubber, and then mixed with compounding agent and raw rubber to produce rubber products. Statistics from the Waste Rubber Comprehensive Utilization Branch of China Rubber Industry Association show that in September 2022, the output of ordinary recycled rubber in China will reach 47000 tons, the output of super recycled rubber will reach 6000 tons, and the output of special recycled rubber will reach 11000 tons.

"Although the recycled rubber produced from waste tires can not completely replace the natural rubber to produce tires, it can replace a small amount of filler to produce rubber products on the premise of no adverse impact on the use performance." Industry experts said that in actual production, the recycled rubber is mainly used to produce agricultural vehicle tyres, bicycle tyres and other non load tyres, as well as rubber hoses, rubber shoes and other products. Especially for low-speed agricultural tyres, when the indicators meet the requirements, a small amount of reclaimed rubber can be used to replace filler, which can partly reduce the production cost of enterprises. At the same time, a small amount of recycled rubber can improve the extrusion and other processing properties of rubber compound.

In the future, with the improvement of the technology level and driven by the market demand, the recycled rubber products will penetrate into the fields of building materials, automobile interiors, etc., and the waste tire recycling industry will also usher in expansion.

3. New use of waste tires

A scientist has successfully developed a high-quality concrete in which all aggregates are replaced by tire particles.

Concrete consists of three parts: water, cement that holds everything together, and aggregates such as sand or gravel.

For a long time, some researchers have tried to replace some sand or gravel with ground tires as concrete aggregate.

However, because the cement cannot bond well with the rubber fragments, and the amount of tire particles is too much, the concrete will lack the compressive strength and splitting tensile strength.

Scientists from the Royal Melbourne University of Technology in Australia found that this adhesion problem was caused by the porosity of tire rubber particles.

When the concrete is initially mixed, the pores in the rubber are filled with water. Once the water evaporates and the concrete solidifies, these pores will become cavities on the rubber/cement interface.

To solve this problem, researchers placed concrete in a special steel mold when it solidified. These molds exert pressure on the concrete to compress the rubber particles and the pores therein.

Compared with the 100% tire aggregate concrete produced by the traditional method, the compressive, flexural and tensile strengths of the new concrete are increased by 97%, 59% and 20% respectively.

4. Why is the success rate of waste tire business so low

There are many kinds of waste tires, and the market recycling prices of each material are different. Take the most common truck tires, which are 650 to 1200. Some of their tires are made of steel wire, some of their materials are made of steel wire, and some of their tires are made of steel wire, including some types of tires that contain inner tubes. These will affect the recycling prices.

The recycling price ranges from dozens to more than 100, so if you don't know these basics, you can recycle them, and you may lose dozens of yuan if you collect a seemingly identical waste tire.

Secondly, in terms of marketing, if the materials of these tires are indistinguishable, let alone the final use of these materials, for example, some tire materials are used for refining, and some are ground rubber powder.