Valorisation Opportunities Related to Wastewater and Animal By-Products Exploitation by the Greek Slaughtering Industry: Current Status and Future Potentials
- First Online:
- Cite this article as:
- Valta, K., Damala, P., Orli, E. et al. Waste Biomass Valor (2015) 6: 927. doi:10.1007/s12649-015-9368-1
The present study aims at uncovering valorisation opportunities in the Greek slaughtering industry related to wastewater and animal by-products exploitation. To this end, 12 Greek slaughterhouses were studied, while literature review of published work on wastewater and animal by-products treatment and valorisation was also conducted. Based on the recording of the existing situation in Greece, it was observed that all slaughterhouses operate biological wastewater treatment plants. The activated sludge process was mostly applied. Animal by-products derived from the operation of the slaughterhouses were mainly treated inside the units through incineration or rendering. In many of the slaughterhouses, animal by-products were treated as being category 1 and, thus, potential by-product valorisation remained unexploited. Moreover, ashes from the incineration of animal by-products and of rendering residues were mainly sent to landfills. Considering the above, in order to add value to the Greek slaughtering industry, anaerobic digestion could be applied instead of the activated sludge process or as a first step prior to aerobic treatment of wastewater resulting in both wastewater treatment and biogas generation. Anaerobic digestion is also an attractive valorisation opportunity for treating animal by-products (category 3 and category 2 after pressure sterilisation). Animal by-products category 3 can also be exploited for the extraction of substances and the subsequent manufacture of feedstuffs, cosmetics or medicinal products. Moreover, separately collected blood can be utilised for the recovery of bioactive peptides to be used in the pharmaceutical industry or as a protein source for pet food. Finally, future valorisation potentials for the Greek slaughtering sector can be found in the ash exploitation as a phosphorous source.