Engineering Commons^™

Thermal Evolution Of Biochar And Its Physicochemical Properties During Hydrothermal Gasification, Sonil Nanda, Ajay K. Dalai, Franco Berruti, Janusz A. Kozinski

Biochar: Production, Characterization and Applications

Biochar is a recalcitrant carbonaceous material obtained from pyrolysis and gasification of biomass and other biogenic wastes. Some of the promising biochar applications to be discussed in this presentation includes char gasification and combustion for energy production, soil remediation, carbon sequestration, catalysis, and development of activated carbon and specialty materials with biomedical and industrial uses. Several factors such as pyrolysis/gasification temperature, heating rates and residence time are the limiting factors that determine the biochar properties such as fixed carbon, volatile matter, mineral matter, surface area, porosity and pore size distribution, alkalinity, electrical conductivity, cation-exchange capacity, etc. This paper will comprehensively …

Oxygen/Steam Charcoal Gasification In A Fluidized Alumina Bed, Rui Moreira, Rui Vaz, António Portugal, Noemí Gil-Lalaguna, Fernando Bimbela, José Luis Sánchez

5th International Congress on Green Process Engineering (GPE 2016)

Mixtures of oxygen and steam were used as gasifying agents to produce a gas stream with high hydrogen content. The effects of the equivalence ratio (ER) and steam to carbon ratio (S/C) on gasification performance were studied at 900 ºC. The highest hydrogen yield (0.412 Nm³/kg charcoal) and apparent energy efficiency (33.43%) were achieved using a mixture that had a S/C ratio of 0.625 and an ER equal to 0.3 (pure oxygen). The results showed that the carbon conversion improved when the ER and the S/C ratio were augmented, and that the production of tars increased when the …

Catalytic Property Of Olivine For Bio-Oil Gasification, Mohammad Latifi, Franco Berruti, Cedric Briens

5th International Congress on Green Process Engineering (GPE 2016)

Introduction

Biomass is an attractive renewable source of fuel and energy. Thermochemical processes can convert biomass to a liquid bio-oil or to a syngas. The advantage of using bio-oil as an intermediate is that, in contrast with both raw biomass and gas, it can easily be produced in small distributed units, stored and transported. Not only can platform chemicals and clean fuels be produced from syngas, but hydrogen is itself an alternative fuel. A high hydrogen production is usually desired: for example, methanol production requires a syngas with a molar H₂/CO ratio of 2. Therefore, maximum hydrogen production …

Choice Of Sewage Sludge Thermochemical Disposal Methods From Multi‐ Perspective Analysis, Dezhen Chen, Min Yang, Yuyan Hu

Life Cycle Assessment and Other Assessment Tools for Waste Management and Resource Optimization

Thermochemical conversion disposal methods for sewage sludge usually include incineration, gasification and pyrolysis. Incineration technology is relatively mature and the incineration ash can be potentially used for phosphorus (P) recovery. Gasification can be used to recover syngas which is convenient to be used for power & heat generation. While through pyrolysis, syngas of high quality, tar and char can be recovered. To make a proper choice from them, these techniques are compared from perspective of technology maturity, investment, operation cost, environmental impact and acceptability of the public. Technology maturity is evaluated by comparing industrial applications. Investment and operation cost are …

Hydrodynamic Study Of A Circulating Fluidized Bed Used For Biomass Gasification Between 20 °C And 900 °C, Sébastien Pecate, Mehrdji Hemati, Mathieu Morin, Yilmaz Kara, Sylvie Valin

Fluidization XV

This work, carried out in the GAYA project frame and subsidized by ADEME, concerns the hydrodynamic study of a 60 kWth circulating fluidized bed pilot plant constructed at the Laboratoire de Génie Chimique in Toulouse for biomass gasification. In that process, biomass gasification and heating of fluidisation material (sand, olivine, catalyst…) which also acts as heat transfer medium, are performed in two separate reactors: a dense fluidized bed and a transported bed. Thermal energy, required in order to heat the fluidisation material, is supplied by the partial combustion of the char produced in the gasification reactor. The hydrodynamic study carried …

H2-Rich Syngas From Renewable Sources By Dual Fluidized Bed Steam Gasification Of Solid Biomass, Christoph Pfeifer, Tobias Pröll, Bernhard Puchner, Hermann Hofbauer

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

Steam gasification of solid biomass yields high quality producer gases that can be used for efficient combined heat and power production (CHP) and as a renewable resource for chemical syntheses. The dual fluidized bed steam gasification technology provides the necessary heat for steam gasification by circulating hot bed material that is heated in a second fluidized bed reactor by combustion of residual biomass char. The hydrogen content in producer gas of such gasifiers is about 40 vol% (dry basis). Addition of carbonates to the bed material and adequate adjustment of operation temperatures in the reactors allow selective transport of CO2 …