Contamination of the organic fraction of municipal solid waste (OFMSW) with xenobiotic compounds and their fate during anaerobic digestion was investigated. The phthalic acid ester di-(2-ethylhexyl)phthalate (DEHP) was identified as the main contaminant in OFMSW in concentrations more than half of the threshold value for the use as fertilizer on agricultural soil in Denmark. Analysis of DEHP in samples before and after large-scale anaerobic digesters revealed higher concentrations of DEHP per kg dry matter in the effluent than in the influent. The concentration of DEHP and DBP (dibutylphthalate) in OFMSW was monitored in the influent and effluent of anaerobic thermophilic (55°C) and hyper-thermophilic (68°C) laboratory-scale reactor systems. In the thermophilic reactors with a hydraulic retention time (HRT) of 15 days 38-70% of DBP was removed, but no consistent removal of DEHP was observed. However, after treatment of the effluent from the thermophilic reactor in a hyper-thermophilic digester (HRT: 5 days) 34-53% of the DEHP content was removed and the DBP removal was increased to further 62-74%. Removal rates (kh) of DEHP and DBP were found to be 0.11-0.32 d-1 and 0.41-0.79 d-1, which is much higher than in previous investigations. It can be concluded that the higher removal rates are due to the higher temperature and higher initial concentrations per kg dry matter. These results suggest that the limiting factor for DEHP degradation is the bioavailability, which is enhanced at higher temperature and higher degradation of solid organic matter, to which the highly hydrophobic DEHP is adsorbed. The investigated reactor configuration with a thermophilic and a hyper-thermophilic treatment is, therefore, a good option for combining high rate degradation of organic matter with high biogas yields and efficient reduction of the phthalic acid ester contamination.
Skip Nav Destination
Article navigation
Research Article|
August 01 2003
Phthalic acid esters found in municipal organic waste: enhanced anaerobic degradation under hyper-thermophilic conditions
H. Hartmann;
1The Environmental Microbiology/Biotechnology Research Group, BioCentrum-DTU, Building 227, The Technical University of Denmark, DK-2800 Lyngby, Denmark (E-mail: bka@biocentrum.dtu.dk)
E-mail: hwh@biocentrum.dtu.dk
Search for other works by this author on:
B.K. Ahring
B.K. Ahring
1The Environmental Microbiology/Biotechnology Research Group, BioCentrum-DTU, Building 227, The Technical University of Denmark, DK-2800 Lyngby, Denmark (E-mail: bka@biocentrum.dtu.dk)
Search for other works by this author on:
Water Sci Technol (2003) 48 (4): 175–183.
Citation
H. Hartmann, B.K. Ahring; Phthalic acid esters found in municipal organic waste: enhanced anaerobic degradation under hyper-thermophilic conditions. Water Sci Technol 1 August 2003; 48 (4): 175–183. doi: https://doi.org/10.2166/wst.2003.0249
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
eBook
Pay-Per-View Access
$38.00