3 research outputs found
Integrated chemical and biochemical technology to produce biogas with a reduced ammonia content from municipal biowaste. Validating lab-scale research in a real operational environment
The current paper reports the scientific, technical, environmental, economic and social impacts of two
integrated chemical and biochemical processes that employed a novel virtuous biowaste cycle under real
operational conditions of three industrial sites in Italy, Greece and Cyprus. The work was based on previous
laboratory research pertinent to the valorisation of municipal biowastes (MBWs) as a feedstock to obtain
value added soluble biobased (SBO) products. The research pointed out that the site-specific nature of MBW
was the main criticality, which could potentially hinder the industrialisation of the MBW-SBO paradigm. The
present work demonstrates the feasibility of a new scenario for a conventional waste treatment plan
collecting and processing MBWs by anaerobic and aerobic fermentation. In essence, the virtuous biowaste
cycle is realised by producing SBO from the plant MBW (process 1) and recirculating it to the MBW feed of
the anaerobic fermentation reactor to reduce the ammonia content in the digestate (process 2). This
mitigates the digestate's environmental impact. Life cycle sustainability assessment demonstrates that the use
of SBO produced from local MBW allowed reducing the ammonia content of the digestate generated from
the local anaerobic fermentation facilities in the three different countries by 21–68% as well its
eutrophication potential. Process 2 allowed at least 86% OPEX cost saving compared to conventional
digestate post-treatment technologies for ammonia abatement, while paying off the CAPEX cost in less than
one year. Socio-economic analysis evaluated the impacts on workers and local community stakeholders,
potentially stemming from the implementation of processes 1 and 2 at European level. The analysis of SBO
composition and performances in each operational site investigated showed that improved performance of
process 2 might be achieved by isolating the active principles in raw SBO prior to their use in process 2.
Chemical and biochemical catalysis by SBO active principles in process 2 support the specific perspective