Waste tyres are engineered composite products containing different rubbers, carbon black, steel, sulphur, zinc, textiles and additives. Pyrolysis can separate and transform these fractions into gas, oil, carbonaceous solids and recovered steel, but product quality determines whether true resource recovery occurs.
Biomass pyrolysis can produce gas, bio-oil and char, but biomass is not a uniform dry fuel. Moisture, ash, lignocellulosic composition and mineral content can materially change process energy demand and product quality.
Bio-organic materials can undergo pyrolysis, but technical possibility does not establish environmental or energetic suitability. High moisture, variable biological composition, salts, ash, contamination and preprocessing can make wet organic streams fundamentally different from dry biomass.
Water contributes mass but not useful fuel value in conventional dry pyrolysis. Heating and evaporating moisture consumes energy before the feedstock itself can reach effective thermochemical-conversion conditions.
Inorganic material does not disappear during thermochemical conversion. Ash-forming minerals and metals can become concentrated, redistributed or transferred into products, particulates and pollution-control residues, affecting process reliability, environmental performance and product use.
A conversion system rarely receives an ideal laboratory feedstock. Sorting, drying, size reduction, contaminant removal and blending are often required to transform variable real-world material into a feedstock the process can handle predictably.
Plastic pyrolysis can convert selected polymer streams into hydrocarbon-rich gases, liquids and solids. Its value depends on polymer composition, contamination, halogens, product upgrading, energy demand, environmental control and whether recovered products genuinely return carbon to productive use.
Chlorine-containing plastics can change pyrolysis chemistry, create corrosive acid gases, contaminate recovered products and increase environmental-control requirements. Even relatively small amounts of contamination can therefore matter.