Waste tyre pyrolysis – A review
Abstract
This review deals with the state-of-the-art of waste tyre pyrolysis for the first time in literature. Pyrolysis has been addressed as an attractive thermochemical process to tackle the waste tyre disposal problem while allowing energy recovery. Pyrolysis enables the separation of carbon black from tyres and the volatile matter released (condensable and non-condensable compounds) has the potential of renewable energy recovery given the significant proportion of natural rubber present in the tyre. Given this waste-to-energy pathway, a comprehensive review has been carried out in order to show the effects of the main process conditions (heating rate, temperature, pressure, carrier gas flow rate and type, volatiles residence time and pyrolysis time) on the physicochemical properties and distributions of the resulting products (gas, liquid and solid fractions). It has also been reviewed the influence of the size and composition of the feedstock. All reported results have been framed regarding the type of reactor as well as the experimental conditions used to avoid contradictions among the large number of publications on the subject. It is shown that the occurrence of secondary reactions is very sensitive to the interaction of the aforementioned variables. Also, the main properties of the pyrolytic products are pointed out. The liquid and gaseous fractions obtained are a valuable fuel source; while the solid fraction (char) has the recovery potential of low- grade carbon black or as carbon adsorbent after applying an activation step. Special attention has been given to the liquid fraction, highlighting its properties as alternative fuel in compression ignition engines.
- Publication:
-
Renewable and Sustainable Energy Reviews
- Pub Date:
- July 2013
- DOI:
- Bibcode:
- 2013RSERv..23..179M
- Keywords:
-
- WT;
- waste tyre;
- NR;
- natural rubber;
- BR;
- butyl rubber;
- CB;
- carbon black;
- SR;
- synthetic rubber;
- SBR;
- styrene–butadiene rubber;
- TDF;
- tyre derived fuel;
- BTX;
- benzenes;
- toluenes and xylenes;
- BTXE;
- benzenes;
- toluenes;
- xylenes and ethylbenzenes;
- PAHs;
- polycyclic aromatic hydrocarbons;
- VOCs;
- volatile organic compounds;
- MSW;
- municipal solid wastes;
- DSC;
- differential scanning calorimetry;
- TG;
- thermogravimetric;
- DTG;
- differential thermogravimetric;
- BFBR;
- bubbling fluidised bed reactor;
- CFBR;
- circulating fluidized bed reactor;
- CSBR;
- conical spouted bed reactor;
- FBR;
- fixed bed reactor;
- AR;
- auger reactor;
- RKR;
- rotary kiln reactor;
- ICE;
- internal combustion engine;
- PCT;
- passenger car tyre;
- TT;
- Truck tyre;
- MT;
- motorcycle tyre;
- IEA;
- international energy agency;
- A;
- Ash;
- VM;
- volatile matter;
- FC;
- fixed carbon;
- M;
- moisture;
- CV;
- calorific value;
- Waste tyre;
- Pyrolysis;
- Thermochemical processes;
- Renewable energy;
- Tyre recovery