Search results for "Biogas"

CO2 capture from biogas: Absorbent selection

2013

The development of proper biogas upgrading technology offers a viable means to utilize biogas in conventional power systems. In this paper, various molecular and ionic solvent systems were evaluated for CO2 removal from biogas in a loop reactor system. The performance of amine solutions, ionic liquids and their mixtures, amino acid salts and solutions blended with piperazine was compared in terms of their CO2 loading capacity. The experimental results revealed that addition of small amounts of piperazine can increase on average by 30 vol% the efficiency of above-mentioned solutions. The CO2 capturing capacity achieved for the most promising solvents was in the range of 50–60 L CO2/L absorbe…

Ionic liquids versus amine solutions in biogas upgrading: the level of volatile organic compounds

2013

Background: This article provides information related to the occurrence of volatile organic compounds before and after biogas purification, by means of both aqueous amine solutions and ionic liquids. Results & discussion: Encouraging results were obtained. Under the experimental conditions, 1-butyl-3-methylimidazolium acetate ionic liquid appeared to perform at least two-times better than aqueous amines solutions, since it captured 65 wt% of the identified volatile organic compounds, while aqueous amine solutions retained around 35 wt% only. However, in the case of octamethylcyclotetrasiloxane and dichlorobenzene, aqueous amine solutions rendered better purification performance and diminish…

Enhancing methane production from lignocellulosic biomass by combined steam-explosion pretreatment and bioaugmentation with cellulolytic bacterium

2017

Background Biogas production from lignocellulosic biomass is generally considered to be challenging due to the recalcitrant nature of this biomass. In this study, the recalcitrance of birch was reduced by applying steam-explosion (SE) pretreatment (210 °C and 10 min). Moreover, bioaugmentation with the cellulolytic bacterium Caldicellulosiruptor bescii was applied to possibly enhance the methane production from steam-exploded birch in an anaerobic digestion (AD) process under thermophilic conditions (62 °C). Results Overall, the combined SE and bioaugmentation enhanced the methane yield up to 140% compared to untreated birch, while SE alone contributed to the major share of methane enhancem…

Cost-benefit analysis: A comparison between conventional and organic olive growing in the Mediterranean Area

2015

The conversion from conventional to organic management of olive growing has many benefits, such as increase of biodiversity, reduction of soil erosion and lower environmental impact. Since olive represents a main crop in the Mediterranean area, from a social, economic as well as environmental point of view, the aim of this paper has been to determine if the conversion from conventional to organic olive growing can increase the profitability of the farmer in Sicilian farms. Economic analysis has been carried out by means of cost-benefit analysis and financial indicators (NPV, B0/C0, IRR) show that organic growing would allow a better profitability for organic olive farms respect to conventio…

Potential of biomethane from washed ashore algae in gulf of Riga

2020

Fully aerobic bioscrubber for the desulfurization of H2S-rich biogas

2019

Abstract A fully aerobic bioscrubber for the desulfurization of H2S-rich biogas was developed in the present study by coupling an absorption column and a bubble column bioreactor. The bioscrubber treated H2S loading rates of 37, 59, and 100 g S mliquid−3 h−1 at gas residence times of 6.6, 4.1 and 2.4 min in the absorption column, respectively. Stable H2S removal efficiencies above 80% were recorded at all the conditions tested. The bioscrubber was robust towards short- and long-term operation shutdowns (5 and 18 days), the H2S removal performance being recovered after few hours. The aerated bubble column bioreactor was operated at slightly alkaline conditions (pH 8 ± 0.5), which prevented H…

Insights into the annotated genome sequence of Methanoculleus bourgensis MS2(T), related to dominant methanogens in biogas-producing plants

2014

The final step of the biogas production process, the methanogenesis, is frequently dominated by members of the genus Methanoculleus. In particular, the species Methanoculleus bourgensis was identified to play a role in different biogas reactor systems. The genome of the type strain M. bourgensis MS2(T), originally isolated from a sewage sludge digestor, was completely sequenced to analyze putative adaptive genome features conferring competitiveness within biogas reactor environments to the strain. Sequencing and assembly of the M. bourgensis MS2(T) genome yielded a chromosome with a size of 2,789,773 bp. Comparative analysis of M. bourgensis MS2(T) and Methanoculleus marisnigri JR1 revealed…

Sicilian potential biogas production from Citrus industry by-product

2017

In Europe, Italy is the second nation after Spain in Citrus production and 49% ca. of national fruit production is located in Sicily. The by-product obtained from the industrial processing of Citrus fruits into juice and essential oils is called “pastazzo” or Citrus Waste (CW). This study is aimed at evaluating the Sicilian potential biogas and energy production from the above “pastazzo” and verifying the possibility of using this by-product for Anaerobic Digestion (AD) process within 30 km from processing plants. The areas cultivated with Citrus species in Sicily and their distribution in the various municipal districts were mapped and analysed by means of QGIS software, together with the …

Generation of heat and power from biogas for stationary applications: boilers, gas engines and turbines, combined heat and power (CHP) plants and fue…

2013

Biogas is produced during the anaerobic degradation of organic material. The produced biogas can be used for heat, electricity or cogeneration of heat and electricity in a combined heat and power plant (CHP). This chapter first discusses the key issues related to combustion of biogas/biomethane in different stationary equipments. It then describes the utilisation of biogas for the generation of electric power and heat in different stationary applications such as boilers, gas engines (CHP), micro turbines and fuel cells.

Effects of temperature on post-methanation of digested dairy cow manure in a farm-scale biogas production system.

2003

A post-methanation process that could be adopted at farm-scale, operating at temperatures prevailing in farm manure digester post-storage tanks, was evaluated. Digested manure samples from a farm digester (35 degrees C) and post-storage tank (5-10 degrees C) were incubated in parallel batches at 5-20 degrees C and as reference at 35 and 55 degrees C. Specific methane yields (kg(-1) volatile solids (VS)(added waste)) were 0.20-0.26 m3 at 35-55 degrees C and 0.085-0.09 m3 at 10-20 degrees C for digester material (345 days of incubation) and 0.16-0.21 m3 at 35-55 degrees C, 0.053-0.087 kg(-1) VS(added waste) m3 at 15-20 degrees C and 0.026 m3 at 10 degrees C for post-storage tank material (250…