Nikolaos Margaritis

Solid fuel types for energy generation: Coal and fossil carbon-derivative solid fuels

Coal plays a decisive role in world energy production as coal-fired plants are responsible for 41% of the global power generation. Rapid industrialization and the worldwide growing energy demands have increased the utilization of coal, as it remains a relative cheap fuel, not associated with market shock prices or geopolitical turbulence. Based on the current production rates, coal reserves will be sufficient for more than 130xa0years. Different types of coal are utilized in different industrial sectors; coal characterization through ASTM procedures or standard analytical methods are used to determine critical properties for the optimization of end use.

4.27 Pyrolysis Energy Conversion Systems

Pyrolysis is regarded as a complex thermochemical process for converting biomass into energy and products consisting of bio-oil, solid biochar, and pyrolytic gas. Pyrolysis temperature significantly influences the properties of products while heating rate defines the type of biomass pyrolysis (fast, slow, etc.). Biochar can be utilized as solid fuel in boilers and other industrial processes, pyrolytic gas can be a renewable alternative fuel for internal combustion engines and other processes, whereas bio-oil has the potential to be used as a fuel oil substitute and transportation fuel. Physical or catalytic upgrading is employed in many cases for converting the bio-oil into useful biofuels and chemicals.

CFD Simulation of Domestic Gasification Boiler

AbstractThis paper describes the simulation of a wood gasification household boiler operation during the period that synthesis gas (syngas), which is produced after gasification, is further combusted for the production of heat that is transferred to the boiler heating surfaces. The particular boiler was designed by an Austrian company for the benefit of a Greek company based in northern Greece, which is currently manufacturing the boiler to test and further optimize it. The nominal fuel power of the boiler is approximately 50u2009u2009kWth and its efficiency is about 90 percent (specifically 88.98 percent). The study is oriented toward the use of computational fluid dynamics (CFD) software as a supporting tool during the design phase of a gasification boiler and focuses on the combustion characteristics and the main gas emission concentrations expected at its outlet. In this study, the boiler is simulated under nominal operating conditions, assuming steady-state conditions as these have been defined by the Austri...

Implementation of a sustainable energy action plan for municipality of Ptolemaida

The first step in the implementation of a SEAP is the collaboration of a BEI, as it will provide knowledge of the nature of the entities emitting CO2 on the municipalitys territory, and will thus help select the appropriate actions. In this paper, the basic methodology is presented, step by step, in order to develop a BEI for the municipality of Ptolemaida in Western Macedonia Region, Greece. According to the results, the final energy consumption of Ptolemaida City amounts to 407,994.00 MWh. Through the use of appropriate selected emission factors the carbon footprint of Ptolemaida was deducted. According to the BEI of Ptolemaida during the year 2010 were emitted 172,518 tn CO2 or 5, 37 tn CO2/capita.