Article pubs.acs.org/EF
Fuel Properties of Tire Pyrolysis Liquid and Its Blends with Diesel Fuel Juan Daniel Martínez,†,‡ Magín Lapuerta,§,* Reyes García-Contreras,§ Ramón Murillo,† and Tomás García† †
Instituto de Carboquímica, ICB-CSIC, Miguel Luesma Castán 4, 50018, Zaragoza, Spain Grupo de Investigaciones Ambientales, Instituto de Energía, Materiales y Medio Ambiente, Universidad Pontificia Bolivariana, Circular 1 N°70-01, Bloque 11, piso 2, Medellín, Colombia § Grupo de Combustibles y Motores, Escuela Técnica Superior de Ingenieros Industriales, Universidad de Castilla La-Mancha, Avda. Camilo José Cela s/n, 13071, Ciudad Real, Spain ‡
ABSTRACT: Pyrolysis is becoming a promising alternative to tackle the waste disposal problem related to used tires as well as for the production of alternative liquid fuels. However, the practical applicability of the products obtained from waste tire pyrolysis has been rather limited. This work aims to increase the knowledge about some key properties of the tire pyrolysis liquid (TPL) obtained in a continuous auger reactor on pilot scale, and its blends with diesel fuel (D). Kinematic viscosity, density, heating value, oxidation stability, lubricity, water content, cold filter plugging point (CFPP), and smoke point have been measured for different TPL/D blends. Values for both pure fuels and blends have been compared to the requirements established for diesel fuel (standard EN 590) and to other TPL properties data reported in literature. Additionally, the flash point, the distillation curve, the calculated cetane index (CCI), and the total acid number (TAN) have also been determined for the pure fuels. These properties show the useful window for the utilization of TPL because they indicate its quality as a fuel in diesel engines or other power systems. Mixing rules for calculating some key properties of TPL/D blends as a function of TPL content have also been used in order to model the blend behavior.
1. INTRODUCTION Used tires are considered a serious pollution problem in terms of waste disposal. The continuous increase of wastes, as well as the petroleum dependence for fuels and essential raw materials, has a negative impact on the environment in most developed countries. Approximately one used tire per capita and per year is produced in these countries.1 Likewise, about 1.5 billion tires are sold worldwide each year, and this amount represents around 20 million tons,2 while 4 billion tires are currently in landfills and stockpiles worldwide.3 Nowadays, both the EU27 plus Turkey and the U.S., generate annually around 300 million waste tires,2,4 and their thermo-mechanical properties make them difficult to be directly reused or recycled without mechanical or thermal pretreatment. Even so, thanks to the landfill directive (1999/31/EC), material recovery is currently the major route for disposing waste tires in Europe. Nowadays, only 4% of the waste tires collected are tipped in landfills or have unknown destination, while the remaining 96% is managed for recycling, recovery, reuse, and retreading.5 However, the material recovery practice just involves the tire grinding, resulting in different tire rubber sizes such as cuts (>300 mm), shreds (20−400 mm), chips (10−50 mm), granulate (0.8−20 mm), and dust (
