Management of waste, sub-products and effluents, with regard to changes in regulations, is a constant concern for manufacturers eager to integrate existing waste-to-energy recycling sectors for certain types of sub-products. The methanisation process forms an interesting alternative to the conventional sectors for the treatment of co-products from the refining of fats and oils.
The purpose of the VECIR project (for Waste-to-energy Recycling of Co-products from Refining) is to offer fats and oils refiners the option of recoveringrefinementco-products, which is long-term, economically viable, and is satisfactory from an environmental point of view.
Theco-products studied are neutralisation pastes, the discolouration and winterisation of spent earth, floating greases,deodorization condensates, tank residue, cakes, and glycerine.
The project is planned over a period of 36 months and is supported by ADEME
and manufacturers from the fats and oils industry.
The programme consists of validating the technical and economic feasibility
of the two strands, by incorporating regulatory constraints:
• strand A: Treatment of refinement co-products on the same site with the
recovery of the biogas produced for the site’s energy requirements, Objective: show that the methanisation of co-products from refining is possible
and that the biogas generated satisfies a proportion of the energy requirements of the refining site,
• strand B: Treatment of spent earth in existing methanisation units in co-
digestion with household refuse
Objective: validate the treatment of spent earth for a household refuse methanisation unit (determine the quantities of spent earth admissible in a digester and assess the resulting performances in terms of yield from biodegradation, production of biogas and any impact on the quality of the digestate).
The programme began in 2008 with different stages:
• bibliographical study,
• Co-products deposit: formulation and sending of a questionnaire to manufacturers, determination of co- products on which tests and sampling will be carried out,
• Characterisation of samples retained for strand A, relating to the treatment of
co-products on the fats and oils production site,
• Determination of the methanogenic potential of co-products retained for strand A,
• Characterisation of samples retained for strand B, relating to the treatment of
the co-products in a household refuse methanisation unit,
• Determination of the methanogenic potential of co-products retained for strand B,
• Realisation of co-digestion tests on a pilot scale of co-products retained for strand B,
• Coordination of the programme.
The first results of the study were published in the Water Science & Technology review (2008 - 58.9, 1871-1878).