Waste disposal management and the energy crisis are important challenges facing most countries. The fruit-processing industry generates daily several tons of wastes, of which the major share comes from banana farms. Anaerobic digestion (AD) technology has been applied to the treatment of wastewater, animal slurry, food waste, and agricultural residues, with the primary goals of energy production and waste elimination. This study examines the effect of organic loading (OL) and cow manure (CM) addition on AD performance when treating banana peel waste (BPW). The maximum daily biogas production rates of banana peels (BPs) with a CM content of 10%, 20%, and 30% at 18 and 22 g of volatile solids (gvs) per liter were 50.20, 48.66, and 62.78 mL·(gvs·d)−1 and 40.49, 29.57, and 46.54 mL·(gvs·d)−1, respectively. However, the daily biogas yield showed no clear interdependence with OL or CM content. In addition, a kinetic analysis using first-order and cone models showed that the kinetic parameters can be influenced by the process parameters.
LINK
High-pressure anaerobic digestion is an appealing concept since it can upgrade biogas directly within the reactor. However, the decline of pH caused by the dissolution of CO2 is the main barrier that prevents a good operating high-pressure anaerobic digestion process. Therefore, in this study, a high-pressure anaerobic digestion was studied to treat high alkalinity synthetic wastewater, which could not be treated in a normal-pressure anaerobic digester. In the high-pressure reactor, the pH value was 7.5 ~ 7.8, and the CH4 content reached 88% at 11 bar. Unlike its normal-pressure counterpart (2285 mg/L acetic acid), the high-pressure reactor ran steadily (without volatile fatty acids inhibition). Furthermore, the microbial community changed in the high-pressure reactor. Specifically, key microbial guilds (Syntrophus (11.2%), Methanosaeta concilii (50.9%), and Methanobrevibacter (26.8%)) were dominant in the high-pressure reactor at 11 bar, indicating their fundamental roles under high-pressure treating high alkalinity synthetic wastewater.
DOCUMENT
Innovations are required in urban infrastructures due to the pressing needs for mitigating climate change and prevent resource depletion. In order to address the slow pace of innovation in urban systems, this paper analyses factors involved in attempts to introduce novel sanitary systems. Today new requirements are important: sanitary systems should have an optimal energy/climate performance, with recovery of resources, and with fewer emissions. Anaerobic digestion has been suggested as an alternative to current aerobic waste water treatment processes. This paper presents an overview of attempts to introduce novel anaerobic sanitation systems for domestic sanitation. The paper identifies main factors that contributed to a premature termination of such attempts. Especially smaller scale anaerobic sanitation systems will probably not be able to compete economically with traditional sewage treatment. However, anaerobic treatment has various advantages for mitigating climate change, removing persistent chemicals, and for the transition to a circular economy. The paper concludes that loss avoidance, both in the sewage system and in the waste water treatment plants, should play a key role in determining experiments that could lead to a transition in sanitation. http://dx.doi.org/10.13044/j.sdewes.d6.0214 LinkedIn: https://www.linkedin.com/in/karel-mulder-163aa96/
MULTIFILE
Biogas produced through Anaerobic Digestion can be seen as a flexible and storable energy carrier. However, the environmental sustainability and efficiency of biogas production is not fully understood. Within this article the use, operation, structure, validation, and results of a model for the environmental assessment of anaerobic biogas production pathways is discussed. The (Excel) BioGas Simulator or EBS model is capable of calculating the economic cost, efficiency, carbon footprint, and sustainability of small scale anaerobic digestion biogas production pathways (from 2000 up to 50000 ton/a biomass input). The results from the model are expressed in four main indicators: the economic cost in Net Present Value (NPV), the efficiency in Process Energy Returned On Invested or (P)EROI, the carbon footprint in Global Warming potential 100 year scale (GWP100), and the environmental impact in EcoPoints. The economic indicator is given in Euros in Net Present Value over a period of 25 years, the other indicators are given per Giga Joule of energy produced (e.g. kgCO2eq/GJ). The EBS model is based on a clear methodology, structured around the modular approach, energy and material flow analysis, and life cycle analysis. The modular approach separates the biogas production pathway into individual physical processes, which makes the model more transparent, flexible in use, and programmable with different settings. The aforementioned allows the research of several aspects of the biogas production pathway. Furthermore, the indication of sustainability in four clear indicators gives an understandable reference for comparison with other scenarios. Overall, the EBS model can help give insight on the sustainability of specific biogas production pathways and help indicate options for improvement. Results from the model indicate that from an energy efficiency and sustainability point of view, the anaerobic digestion process should be utilized for treating locally available waste feedstocks with the added advantage of producing energy, which should preferentially be used internally for powering the waste treatment process.
LINK
Many articles have been published on scale-down concepts as well as additive manufacturing techniques. However, information is scarce when miniaturization and 3D printing are applied in the fabrication of bioreactor systems. Therefore, garnering information for the interfaces between miniaturization and 3D printing becomes important and essential. The first goal is to examine the miniaturization aspects concerning bioreactor screening systems. The second goal is to review successful modalities of 3D printing and its applications in bioreactor manufacturing. This paper intends to provide information on anaerobic digestion process intensification by fusion of miniaturization technique and 3D printing technology. In particular, it gives a perspective on the challenges of 3D printing and the options of miniature bioreactor systems for process high-throughput screening.
LINK
Next-generation sequencing technology allows culture- independent analysis of species and genes present in a complex microbial community. Such metagenomics may overcome the inability to culture microbes in isolation. Microbial communities of interest are for example responsible for making biogas. Many applications in metagenomics focus on 16S RNA analysis. We here evaluate the possibility of whole genome analysis (WGS) as approach for metagenomics studies.Samples (Table 1) from three biogas installations fed with different feedstock were used for DNA isolation and WGS analysis. Short (75b) Illumina paired-end DNA sequence reads were generated and assembled into larger continuous stretches (contigs),AcknowledgementsResults show that WGS is feasible for complex community analysis. Large groups of organisms (for example the class Methanomicrobia) are present in all samples with a possible role in the biogas production pathway.Assemble reads into contigs•meta-velveth as metagenomics reads assemblerSequencesimilaritysearch•proteome reference database from all currently available Bacteria and Achaea genomesAssign hits to taxa•Lowest common ancestor method incorporated in MEGAN4Such studies will help to identify and use microbial species for future improvements of biogas production dependence on process parameters and feedstock.
DOCUMENT
Organic wastes like cooking-waste, farm-waste and manure have detrimental effect on the environment, health and hygiene of people. Within India there are possibilities to manage the available biomass in an efficient way, which can bringenvironmental, health and economic benefits. Through anaerobic digestion, biomass can be converted into biogas and digestate, which can be used as renewable energy source and fertilizer respectively. However, there is a lack of knowledge on how to use the available biomass and, thus, its products in a beneficial way. This leads to the main question: How to fit biogas productionwithin the existing energy infrastructure of India? Our approach involves modelling biogas chains from production to consumption and then analyse several different options. Within the Flexigas project a flexible BioGas simulator is being created, which is capable of simulating biogas production and consumption process. The simulator takes into account the location andavailability of biomass, different biomass and biogas transport, anaerobic digesters, biogas upgraders and various cost involved in the biogas production process. A multi-touch User Interface is used for simulation control and result visualization. Results from the simulator shows how feasible it is to set up the biogas chains, its advantages and increases knowledge on effective biomass use.
DOCUMENT
Agricultural by-products, that is primary residue, industrial by-products and animal manure, are an important source of nutrients and carbon for maintaining soil quality and crop production but can also be valorised through treatment pathways such as fermentation, incineration or a combination of these called bio-refinery. Here, we provide an overview of opportunity to reduce environmental impact of valorising agricultural by-products. We estimate the available by-products in Northwestern Europe as a case study and the maximum and realistic greenhouse gas reduction potentials. Availability, collectability, the original use and environmental impact including land use changes, soil carbon sequestration and pollution swapping are discussed as critical factors when valorising agricultural by-products.
DOCUMENT
The Bio-P2G-program (Bio-Power to Gas) at the Hanze University of AppliedSciences evaluates the technologic feasibility of the biological reduction of carbondioxide with hydrogen to methane (biomethanation: 1 CO2 + 4 H2 -> CH4 + 2 H2O)Chemically, this process is known as the Sabatier reaction, but within anaerobicdigestion the biological methanation is catalyzed by a specific group ofmicroorganisms: the hydrogenotrophic methanogens.
DOCUMENT
Biopolymeren vormen een potentieel interessant alternatief voor conventioneel op olie gebaseerde polymeren, omdat zij geen fossiele grondstoffen gebruiken voor de productie. Daarentegen is het productie procedé afhankelijk van energie en toevoegmiddelen die weer bijdragen aan het verbruik van energie en de emissie van onder andere broeikasgassen en zijn de grondstoffen van belang, zoals het gebruik van reststromen uit de afvalverwerking of andere biomaterialen. Binnen het project Circulaire Biopolymeren Waardeketens zijn meerdere productiemethoden bestudeerd om polyhydroxyalkanoaten (PHAs) te maken uit organische reststromen: GFT en afvalwaterslib, een bijproduct uit de afvalwaterzuivering. Productie en extractie van PHAs kan middels diverse routes. In het project zijn meerdere extractieroutes bestudeerd betreffende hun mogelijkheden. Als onderdeel van het project is een levenscyclusanalyse (LCA) gedaan om de milieu-impact van de productie van de biopolymeren in kaart te brengen.
DOCUMENT
