Every year, millions of tyres reach the end of their working life. Because tyres are built to survive heat, pressure, and years of wear, they don't break down on their own — piled up, they become fire hazards and environmental liabilities instead of simply disappearing. Tyre pyrolysis is the process that solves this: it takes a material designed to last forever and turns it into something useful again. Here's how it actually works, stage by stage.
1. Preparing the feedstock
Before a tyre ever reaches the reactor, it's shredded into small chips — typically in the 20–25 mm range, with as much of the internal steel wire removed as possible. Smaller, more uniform chips heat evenly and keep the process running smoothly; oversized pieces or excess wire content can slow decomposition and reduce output quality.
2. Loading the reactor without letting air in
This is the detail that makes continuous pyrolysis plants tricky to engineer well: the tyre chips have to get into a sealed reactor without ever letting oxygen in with them. A dual-hopper feeding system handles this by using airtight valves in sequence — one hopper loads while the other is sealed, so there's always a barrier between the outside air and the reaction chamber. Oxygen inside the reactor isn't just inefficient, it's a genuine fire and explosion risk, so this sealing step is treated as a core safety system, not a minor detail.
3. Heating in an oxygen-free environment
Once inside, the tyre chips are heated to high temperatures — generally in the 300–450°C range for the reaction to complete efficiently — inside a chamber with no oxygen present. This absence of oxygen is what separates pyrolysis from ordinary burning. In a fire, oxygen reacts with rubber and releases smoke, soot, and toxic fumes. In pyrolysis, with no oxygen available, the rubber can't combust. Instead, heat alone breaks the long hydrocarbon chains that make up the rubber compound, converting the solid material into a mix of hot vapor and solid carbon residue — a process called thermal decomposition, or "cracking."
4. Condensing the vapor into oil
The vapor produced inside the reactor is a complex mix of hydrocarbon gases. As it exits the reactor, it passes through a condensing system — typically a staged setup, where heavier hydrocarbon vapors are cooled and liquefied first, followed by a second stage that captures lighter fractions that would otherwise escape as gas. As the vapor cools, most of it condenses back into a liquid: pyrolysis oil. This oil collects in storage tanks and is typically dark, viscous, and energy-dense — usable directly as an industrial fuel in burners and furnaces.
5. Recovering the leftover gas
Not everything condenses. A portion of the gas stream remains non-condensable even after cooling — this is the combustible syngas. Rather than venting or flaring it, well-designed pyrolysis plants recycle this gas back into the system, burning it to help heat the reactor itself. This is one of the process's built-in efficiencies: the plant partially fuels its own operation from a byproduct that would otherwise be wasted.
6. Collecting the carbon char
What's left behind in the reactor after the vapor has been driven off is a solid black residue — carbon char (sometimes called char carbon, or, after further processing, recovered carbon black/rCB). This is cooled and discharged through a sealed conveying system so it doesn't reintroduce oxygen into the reactor as it's removed. Char has industrial uses on its own — as a solid fuel in furnaces — and can be further refined into higher-grade carbon black for use in inks, coatings, rubber compounding, and other applications.
7. Cleaning up the exhaust
The small amount of flue gas produced during heating (from burning fuel oil or syngas to run the reactor) is passed through a purification and dust-removal system before it's released through a chimney, keeping emissions within pollution-control-board limits.
Why it matters
Done properly, tyre pyrolysis turns a stubborn waste problem into three usable outputs — oil, carbon, and reclaimed gas — without burning the tyres and without leaving them to sit in landfills or by the roadside, where they're a fire risk and a source of land and water contamination. It's not a perfect or instant fix to the scale of global tyre waste, but as a way to recover real value from something that would otherwise just be a liability, it's one of the more practical tools available today — and it's the process at the core of what we do every day at our Morbi facility.