• Energy Research

In Campania Region, the rise in Buffalo heads reared plays an important role in the manure management of the region. Moreover, in order to comply with the European regulation (the National Emission Ceiling), the updating of national emission inventories, as well as the investigation of different fertilizers, manure treatments prior to field application and innovative reducing ammonia techniques, are necessary. Specifically, controlling emissions techniques should help farms both during the storage period and during the spreading activities. Indeed, both steps in manure management affect the total ammonia volatilization. To this purpose, this paper presents an innovative view of the manure management system. The interaction between Biochar (a solid material obtained from the thermochemical conversion of biomass in an oxygen-limited environment) and manure was evaluated, adding a commercial Biochar to the liquid fraction of buffalo digestate in the storage tank. The data obtained suggest that a reduction in ammonia emissions is still possible. A reduction in terms of ammonia emissions was recorded during the storage period due to nutrient retention capabilities of biochar. Specifically, Digestate without any coverage proved to emit 58% more than the same digestate covered by a 2 cm of biochar. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 860-863

Campania region is undergoing a new and important land use change (LUC). Large areas under tobacco are experiencing a severe economic crisis and cereal areas, especially in the hill, are cultivated with increasing difficulty, with poor economic results (yield value of 2.5 t/ha/year) and under the risk of erosion. No-food crops suitable in these contexts are the perennial and in this case, the land use change would certainly lead to a positive impact on reducing erosion, but also on the reduction of nutrient requirement, on fuel consumption and perhaps it would also lead to an increase in profitability. The aim of this work is to identify the areas in which the land use change could be realistic and ecologically compatible and to evaluate the main consequence of the LUC. The study area includes the entire Campania region. It has been assumed that the areas that will undergo the LUC will be the hilly, not-irrigated cereal crop, with altitudes between 400 and 750 m a.s.l., not included in natural parks, in the Site of Community Importance and in the Special Protection Areas. Through the climate model, inferred from the Ground Water Protection Plan, the area to be examined was classified as ‘cold Lauretum’, which is a good area for the Arundo donax crops up to 750 m a.l.s., with recoverable biomass yield of about 12.6 t/year. The erosion has been estimated with RUSLE applied to the whole region. Using the ESRI ArcGis 10.0 software, seven large areas, partially convertible, were identified. The area that is realistic to convert amounted to approximately 500 km2. The value of the biomass production has been evaluated in the order of 25 million euro a year; actual wheat production would be 33 million euro a year but the production costs are far greater. With LUC there is a reduction in soil erosion in the order of 300000 t/year. This would lead a saving, on global scale, in the order of 10 million tonnes of CO2 per year.

The storage of livestock manure is responsible for ammonia emissions into the atmosphere. Different natural covers could be used during animal manure storage, but the mitigation effect is influenced by the manure characteristics due to the housing or treatment systems. Starting from cattle and buffalo manure, the objectives of this study were (i) to assess the effect of anaerobic digestion (AD) and solid–liquid separation (SLS) on ammonia emissions during storage as well as natural crust development and (ii) to investigate the reduction in ammonia emissions by using a layer of straw to cover the stored animal manure. Storage conditions were simulated in a small-scale application in a climate-controlled room. Results showed that the higher organic matter content of cow raw slurry facilitated the surface crust formation starting from the first days of storage. AD with SLS increased ammonia emissions (48.5%) due to the increase of the ammoniacal nitrogen content. On the other hand, animal manure covered with a layer of straw showed a 7.3% reduction of ammonia emissions. This study suggests that treatments and covering strategies must be calibrated to different manure types to enhance the mitigation effect.

In the last two centuries, land-use change (LUC) has been the most important direct change driver for terrestrial ecosystems. In contrast with the consequent ecosystem degradation, forward-looking spatial policies and target landscape and land-use planning processes are needed from a sustainability perspective. The present paper proposes a framework of action, including different landscape-planning and ecological approaches: from spatial modelling to recognize LUC and build different scenarios, to ecosystem service (ES) assessment to evaluate possible environmental impacts. Three different scenarios were explored: Trend, No Tillage, and Energy crops. The sediment delivery ratio and carbon storage and sequestration ESs were assessed and compared for each scenario. The results show that regional development in line with past trends could lead to further land degradation (with ES value losses, in a decade, greater than 5%). Instead, the two scenarios proposed in compliance with EU policies could bring benefits, if only those related to moderate LUCs and respecting the naturally grass-vegetated land. The aim of the paper is to support decision makers and local communities in the landscape planning landscape planning process. From the local to global scale, guided and shared LUC management allows us to implement sustainable development, based not only on a deep knowledge of the physical environment but also of social and economic issues.

Anaerobic digestion (AD) is a mature technology commonly used for manure treatment, both for the stabilisation of waste and for the production of energy. The introduction of new incentives could represent an opportunity for biogas production, when the current feed-in-tariffs, which improved the financial feasibility of AD plants producing electricity will end. This paper examines the feasibility of reconverting an existing AD biogas production plant into a biomethane production plant. The AD plant, in this case study, is a two-stage reactor situated in the centre of Italy and mainly fed with livestock manure from both cows and buffaloes. The economic analysis of two hypotheses is provided: i) continuing the electricity production from biogas after the end of the current incentives (2025); ii) considering the new incentives program for the biomethane and reconverting the plant, using hollow-fibre membranes for the purification of the raw biogas (SEPURAN® Green modules, EnviTec). For this purpose, investment and operating costs, based on plant monitoring data (2105.3 m3 d–1, Biogas production; 4432.9 kWh d–1, electricity production) as well as on market analysis for costs evaluation were considered. The mean biogas production for the considered year was about 30% less than the expected production, indicated by producer, highlighting the need for the optimisation of the management of the reactors. Moreover, based on the averaged methane production (June 2017-June 2018), results show that: i) plant conversion for the biomethane production is not suitable for small-scale plants, due to the high investment costs of upgrading technology (1.2 M€); ii) when current incentives end, the electricity production from biogas in the current plant may not be self-sufficient, due to the highly expensive operating costs. This paper provides a first analysis of the possible fate of the biogas plants under the new incentives.

This study investigates the dark fermentation of fruit and vegetable waste under mesophilic conditions (30–34 °C), as a valorization route for H2 and volatile fatty acids production, simulating the open market waste composition over the year in two Mediterranean countries. Specifically, the study focuses on the effect of the (i) seasonal variability, (ii) initial pH, and (iii) substrate/inoculum ratio on the yields and composition of the main end products. Concerning the seasonal variation, the summer and spring mixtures led to +16.8 and +21.7% higher H2 production than the winter/autumn mixture, respectively. Further investigation on the least productive substrate (winter/autumn) led to 193.0 ± 7.4 NmL of H2 g VS−1 at a pH of 5.5 and a substrate/inoculum of 1. With the same substrate, at a pH of 7.5, the highest acetic acid yield of 7.0 mmol/g VS was observed, with acetic acid corresponding to 78.2% of the total acids. Whereas a substrate/inoculum of 3 resulted in the lowest H2 yield, amounting to 111.2 ± 7.6 NmL of H2 g VS−1, due to a decrease of the pH to 4.8, which likely caused an inhibitory effect by undissociated acids. This study demonstrates that dark fermentation can be a valuable strategy to efficiently manage such leftovers, rather than landfilling or improperly treating them.

This study deals with the innovative micro-injection technique, which allows the slurry to be injected at 5 cm deep into the soil with a reduced traction force, a crucial point for the farms. To this purpose, two slurry spreading techniques were compared in laboratory under controlled temperature and humidity conditions: (i) the band spreading application (BS) and (ii) the microinjection application (MI) of a liquid fraction of cow digestate. The slurry spreading was simulated using 6 glass vessels filled by 3770 g of sieved soil at 5 mm, characterized by a water-filled pore space (WFPS) of 60%. During a monitoring period of 5 days after the slurry application, ammonia and methane emissions were measured. The cumulative ammonia emissions measured for the band spreading and micro-injection were 985,2 mgN m-2 and 24,6 mgN m-2, respectively. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 864-866