Pyrolysis and combustion of waste lubricant oil from diesel cars: Decomposition and pollutants

✍ Scribed by M.J. Fuentes; R. Font; M.F. Gómez-Rico; I. Martín-Gullón

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 674 KB
• Volume: 79
• Category: Article
• ISSN: 0165-2370
• DOI: 10.1016/j.jaap.2006.12.004

✦ Synopsis

Pyrolysis and combustion of waste lubricant oil were studied due to its important potential value as a fuel. A thermogravimetric analysis in nitrogen atmosphere conditions and with different proportions of nitrogen:oxygen (N 2 , N 2 :O 2 mixtures at 4:1 and 9:1 ratios), different weights (1, 2.5 and 5 mg) and different heating rates (5, 10 and 15 8C min À1 ) were carried out to study the thermal decomposition. Both pyrolysis and combustion can be represented in two processes: in the first process, a volatilization of the oil takes place (this depends on the initial mass and the heating rate) and in the second process there is a decomposition, which is a different process in combustion from the process in pyrolysis.

The identification of the volatile and semivolatile compounds from pyrolysis and combustion of used diesel oil was carried out in a tubular reactor at 500 and 850 8C. On the one hand, the semivolatile PAH compounds (naphthalene, phenanthrene, anthracene, etc.) were detected as much in pyrolysis as in combustion (850 8C), but the most highly carcinogenic is benzo(a)pyrene which was only found in pyrolysis at 850 8C. On the other hand, the levels of PCDD/Fs and dioxin-like PCBs were estimated after a fuel-rich combustion process at around 113 pg WHO-TEQ g À1 burnt oil (corresponding to 80 pg I-TEQ g À1 ) and 3 pg WHO-TEQ g À1 burnt oil, respectively. The PCDD/Fs concentration in the raw sample was estimated at around 7-16 pg WHO-TEQ g À1 used oil (or 6-13 pg I-TEQ g À1 ) and PCBs were not detected.