Materials and Tools across Volcanoes: Exploitation of Georesources in Piano dei Cardoni (Ustica, Italy) during Prehistory

The paper aims at merging the first results from the analyses of the georesources exploited in the site of Piano dei Cardoni (Ustica island, Italy) during the Neolithic phases of its occupation (Middle-Late Neolithic, 4.7-4.2 ka cal BC). Grinding tools consist of a very varied typology of local volcanic rocks, easy to collect and available very close to the investigated site. A selection of shapes and lithology is applied to reach the best performance of the tools. The elevated number of grinders, pestles, mortars testify to an intense activity of food/plant processing in the site. The absence of chert or obsidian resources on the island pushed the human communities to import such raw materials from the Aeolian islands and probably from the north-western area of Palermo. Pumice is collected on the same island, probably due to the local availability and its good quality. Similarly, local clay resources are used for the manufacture of ceramics, mostly burnished and incised wares. Ustica was therefore almost autonomous for the exploitation of resources, with volcanic rocks readily available in abundance and with the most significant exception being chert and obsidian. This last one probably imported and worked on the island and then moved towards North-Western Sicily.

Techno-Economic Assessment of Biological Biogas Upgrading Based on Danish Biogas Plants

Biological biogas upgrading with H2 derived from excess renewable electricity was modeled and simulated in PROII® (AVEVA Group plc, Cambridge, UK). An economic analysis was performed for a biogas plant processing 100,000 tons of biomass (substrate) per year. The biogas and biomethane production simulation results were validated with laboratory experimental data, as well as full-scale data obtained from biogas plants. A biomethane production cost of 0.47 €/Nm3 was calculated, while the minimum biomethane selling price for NPV = 0 was equal to 0.66 €/Nm3, considering a H2 price of 1.0 €/kg. The feasibility analysis indicated that the H2-related costs were the major contributor to the capital and operation costs due to high expenses associated with the in-situ H2 storage facility and the purchasing of H2, respectively. Compared to conventional upgrading methods, biological biogas upgrading has a higher capital and production cost, which can be reduced by increasing the plant capacity. The sensitivity analysis showed that the profitability is very sensitive to biomethane prices, capital investment, and the H2 price.

Wild cereal grain consumption among Early Holocene foragers of the Balkans predates the arrival of agriculture

Forager focus on wild cereal plants has been documented in the core zone of domestication in southwestern Asia, while evidence for forager use of wild grass grains remains sporadic elsewhere. In this paper, we present starch grain and phytolith analyses of dental calculus from 60 Mesolithic and Early Neolithic individuals from five sites in the Danube Gorges of the central Balkans. This zone was inhabited by likely complex Holocene foragers for several millennia before the appearance of the first farmers ~6200 cal BC. We also analyzed forager ground stone tools for evidence of plant processing. Our results based on the study of dental calculus show that certain species of Poaceae (species of the genus Aegilops) were used since the Early Mesolithic, while ground stone tools exhibit traces of a developed grass grain processing technology. The adoption of domesticated plants in this region after ~6500 cal BC might have been eased by the existing familiarity with wild cereals.

Potential of Energy Municipal Solid Waste (MSW) to Become Refuse Derived Fuel (RDF) in Bali Province, Indonesia

The generation of municipal solid waste (MSW) in Bali has various environmental impacts. One of the updates on sustainable waste processing is the RDF treatment plant processing. Before carrying out the processing, MSW characterization is needed because each region has a diverse composition. The processing of MSW into RDF provides benefits for achieving MSW reduction targets, renewable energy use, and the reduction of greenhouse gas (GHG) emissions. For this reason, this study was conducted to determine the potential of MSW in Bali as an alternative to renewable fuel and its potential to reduce GHG. MSW's potential calorific value as a raw material for RDF in Bali can reach 9.58 - 17.71 MJ/kg. The implementation of processing waste into RDF in pellets has shown a calorific value of ± 3904 - 4945 kkcal/kg. Implementing MSW processing into RDF in Bali can reduce GHG by 178 - 330 times compared to open dumping.

Risk Analysis on PMMA Recycling Economics

Poly(methyl methacrylate) (PMMA) is a versatile polymer with a forecast market of 4 Mtons/y by 2025, and 6 USD billion by 2027. Each year, 10% of the produced cast sheets, extrusion sheets, or granules PMMA end up as post-production waste, accounting for approximately 30 000 tons/y in Europe only. To guide the future recycling efforts, we investigated the risks of depolymerization process economics for different PMMA scraps feedstock, capital expenditure (CAPEX), and regenerated MMA (r-MMA) prices via a Monte-Carlo simulation. An analysis of plastic recycling plants operating with similar technologies confirmed how a maximum 10 M USD plant (median cost) is what a company should aim for, based on our hypothesis. The capital investment and the r-MMA quality have the main impacts on the profitability. Depending on the pursued outcome, we identified three most suitable scenarios. Lower capital-intensive plants (Scenarios 4 and 8) provide the fastest payback time, but this generates a lower quality monomer, and therefore lower appeal on the long term. On 10 or 20 years of operation, companies should target the very best r-MMA quality, to achieve the highest net present value (Scenario 6). Product quality comes from the feedstock choice, depolymerization, and purification technologies. Counterintuitively, a plant processing low quality scraps available for free (Scenario 7), and therefore producing low purity r-MMA, has the highest probability of negative net present value after 10 years of operation, making it a high-risk scenario. Western countries (especially Europe), call for more and more pure r-MMA, hopefully comparable to the virgin material. With legislations on recycled products becoming more stringent, low quality product might not find a market in the future. To convince shareholders and government bodies, companies should demonstrate how funds and subsidies directly translate into higher quality products (more attractive to costumers), more economically viable, and with a wider market.

A Survey of Kocho Processing Practice and Challenges to Scientific Developments

Kocho is a food product made from the decortication and fermentation of enset parts. A quarter of Ethiopia’s population lived in the south and south-western parts of the country, where staples or co-staples were used as a food source. Kocho preparation consists of several steps, all of which are still carried out using indigenous knowledge and traditional practices. Despite its benefits, enset plant processing for food preparation is time consuming, unsanitary, requires a long fermentation period, is low in protein, and has a strong odor. The unusual sensory characteristics are the result of microbial spoilage caused by Kocho’s high moisture content. High moisture content encourages the growth of spoilage microorganisms, which produce unpleasant organic compounds. Kocho’s nutritional and organoleptic properties may thus be process-related. Nutrient loss and time-consuming fermentation processes are common and vary by location. Furthermore, accurate understanding and introduction of these processes in both enset growing and nongrowing regions can help to improve, standardize, and increase the process’s utilization in order to contribute to the country’s food security. However, there has been little research on the preservation of kocho by chemical ingredients and natural species, as well as microbes involved in fermentation and spoilage. Furthermore, very few studies on the effect of biochemical and the role of fermentation on the degradation of anti-nutritional factors have been reported. It can be stored for years and, like other fermented foods, can inhibit the growth of pathogenic bacteria, extending product shelf-life while ensuring consumer safety. Above all, this review is being conducted with the goal of reviewing the kocho processing practices and challenges to Scientific developments. Similarly, the document attempts to provide a brief description of its common characteristics in terms of microbial, biochemical, and fermentation conditions.

A microbotanical and microwear perspective to plant processing activities and foodways at Neolithic Çatalhöyük

Çatalhöyük is a renowned archaeological site in central Anatolia, best known for its Neolithic occupation dated from 7100 to 6000 cal BC. The site received worldwide attention early on for its large size, well-preserved mudbrick architecture, and elaborate wall paintings. Excavations at the site over almost three decades have unearthed rich archaeobotanical remains and a diverse ground stone assemblage produced by what once was a vibrant farming community. The study presented here adds to our understanding of crops and plant processing at Çatalhöyük by integrating phytoliths and starch analyses on grinding implements found at three domestic contexts attributed to the Middle (6700–6500 cal BC) and Late (6500–6300 cal BC) period of occupation. Our results reveal a rich microbotanical assemblage that testifies the use of a wide range of geophytes and wild seasonal resources previously unknown at the site. Moreover, by comparing results from the microbotanical proxies and microscopic wear patterns on artefacts, we are also able to discern various plant processing practices the analysed artefacts were employed for. In sum, this work further expands our understanding of plants and crop processing activities performed by the inhabitants of Neolithic Çatalhöyük.