Ricerc@Sapienza

Polyhydroxyalkanoates (PHAs) are well-known biodegradable plastics produced by various bacterial strains, whose major drawback is constituted by the high cost of their synthesis. Producing PHAs from mixed microbial cultures and employing organic wastes as a carbon source allows us to both reduce cost and valorize available renewable resources, such as food waste and sewage sludge. However, different types of pollutants, originally contained in organic matrices, could persist into the final product, thus compromising their safety.

The organic solid waste and sewage sludge management has important consequences on the overall environmental and economic performance of urban waste management systems. The RESURBIS is a Horizon 2020 project that proposes a biorefinery concept for the combined treatment of all the bio-waste produced in an urban area, mainly focusing on the production of polyhydroxyalkanoate (PHA).

Although the organic fraction of municipal solid waste (OFMSW) and sewage sludge (SS) originate from the same urban area and contain similar organic matter, they are collected separately and handled with different technologies. In this work, a combined treatment of OFMSW-SS mixture was investigated at pilot scale, by using a three-step mixed microbial culture (MMC) process in order to produce polyhydroxyalkanoate (PHA) as final high value biobased product.

The updated Bioeconomy Strategy document “A sustainable bioeconomy for Europe: strengthening the connection between economy, society and the environment”, which was issued by the European Commission in October 2018, encourages the exploitation of organic wastes according to a pyramidal hierarchy in which the extraction of valuable biomolecules, which will be used as they are or as precursors of high-added-value compounds, is a priority in biofuel production.

Recycling and recovering valuable resources from wastewater treatment plants is an important aspect in circular economy. The safe use of sludge and sludge-related products deriving from wastewater treatment strictly depends on their chemical contamination, especially by emerging pollutants. In this work, an analytical method was developed for the determination of a range of selected compounds, included in a recent European watch-list (macrolides, fluoroquinolones, neonicotinoids, carbamates and estrogens), in recovery materials from innovative pilot systems.