The good practices for biogas- biomethane chain
In Italy, biomethane is the biofuel to invest in to achieve the targets set for 2020. At the moment the national chain of anaerobic digestion of organic matrices stops at the biogas stage with high technological levels and an excellent production system. The next step will be the upgrading of biogas to biomethane. A decree will be issued to encourage the use of biomethane in the transport sector
In Italy, a decree to encourage the use of biomethane in the transporzt sector will be soon approved. This law aims to give an impulse to the development of a renewable energy carrier, and to reach the target of 10% of biofuel to be used for the national vehicle fleet by 2020.
Before this imminent decree, as early as 17 December 2013 a previous regulatory act, approved by the Ministry of the Economic Development in cooperation with the Ministry of the Environment and the Ministry of Agriculture, established the methods for a sustainable use of biomethane within a wider energy field that, in addition to transport, involved the electrical and thermal power sectors. Unfortunately, a series of steps, which have never been implemented, have considerably limited its effectiveness. Despite that, this law had the merit to set up a common pathway for all the shareholders involved.
To date, the national anaerobic digestion stops at the biogas level, and the upgrading from biogas to biomethane is the next step to be taken. However, at this level, the integration between innovative technologies and a clever management of the production chain continues to evolve, creating the conditions for promoting the use of biomethane in the near future.
Breaking down a series of non-technological barriers is essential. These barriers are slowing down significantly the development of what in Italy is in fact the most promising alternative to fossil fuels. For example, as part of the H2020 ISAAC Project (Increasing Social Acceptance and Awareness of Biogas) – among the various actions undertaken – training courses for technicians of the regional administrations of Marche and Puglia were organized and carried out. These courses provided technicians with useful elements for the planning and authorization process of the biogas-biomethane sector in local areas. This four-day course for each Region (with some lessons held at the Agrilevante exhibition Bari) was coordinated by the Bionet Green Chemistry Association in collaboration with ITABIA, with first-rate experts illustrating the technological, regulatory, environmental and social aspects of the biogas-biomethane chain and analyzing its strengths and weaknesses. Particular attention was paid to good practices, taken as reference models.
The good practices in the field of biogas are in fact sustainable chains well integrated with the territory and in particular with livestock farms, where anaerobic digestion is given by a mix of organic matrices made up of crop and agro-industrial residues, livestock effluents and limited parts of second harvest crops.
Identifying good practices and spreading them is extremely useful for the development of this sector. This process ensures that sound models in a technical and environmental perspective can be replicated, in order to counter the phenomenon of NIMBY which represents a huge challenge.
For several years, in reaction to the economic crisis that also affected the primary sector, biogas has been seen as an opportunity for modernization. It has also given the chance to many farms to produce quality food with a view to an effective planning aimed at promoting the multi-functionality of businesses.
These initiatives, led by motivated and responsible entrepreneurs encompass an extensive strategy which has been drawn up at European and international level to counter climate change and improve the safeguarding of agro-ecosystems. The first 2-stage biogas plant has recently started up in Soliera (Modena). This plant stands out from the traditional single-stage units already operating due to a technological innovation – patented by ENEA and CREA – which allows significantly higher biogas yields (+20%), to supply a 100KW electric generator. The improved efficiency of this system is the result of a process of adaptation of mechanical components to the knowledge acquired in the field of microbial ecology. Overall, anaerobic digestion improves significantly by separating, in different reactors, the first phases of the process (hydrolysis and acidogenesis) from the remaining ones (acetogenesis and methanogenesis). This is because the two initial phases are carried out by specific strains of bacteria which operate in a shorter period (a few days) and at lower pH values (5-6) than the other two. Moreover, in the first stage of the process the hydrogen which is being produced can be used for further increasing biomethane production at the end of the cycle. Alternatively, it can be directly used as a gaseous biofuel in mixture with methane (hydromethane) or to fuel fuel cells. To conclude, by improving the environmental conditions (chemical-physical parameters), the selected cultures of micro-organisms can work more and better. Therefore, compared to the most used technologies available on the market, the plants are smaller with a consequent containment of costs. The Soliera Plant is an example of good practice, both for its highly technological content, and for the collaboration between public bodies, Enea and Crea, and the Biogas Italia start-up together with the Lugli farm. A further strong point is the planned monitoring of the operations and performance of the plant over a long time. This initiative will provide indications and information useful for replicating this experience in similar contexts both in Italy and abroad.
“Biogasfattobene”
The objective of the Internal Regulations, to which the biogasfattobene® brand is connected, supported by the CIB and Enama (National Agency for Agricultural Mechanization), is to promote the culture of quality, environment and safety in companies, and to certify it by increasing a positive attitude of the public towards anaerobic digestion. In this management model a perfect integration exists between system and technical requirements. Companies that intend to obtain the biogasfattobene® brand are required to comply with precise management and transparency rules for the main processes of the supply chain, from the phase of biomass acquisition and its use to the agronomic use of the digestate. For the time being, the biogasfattobene® brand has been issued to the following two plants:
The CAT (Territorial Agro-energy District) of Correggio (Reggio Emilia), which brings together 26 farms and 5 social wineries. The plant has an electric power of 1MW and dedicates to anaerobic digestion the substrates obtained from experimental crops of second harvest (corn, triticale and sorghum) and sown on hard ground on a 350-hectare area.
The Tosi Francesco & Figli company, located in Villanterio (Pavia), uses effluents of pig breeding, silage and residues of agricultural crops.
