Improving Carbon and Process Utilization for Biomass-to-Liquid Fuel Operations

With the increasing world demand for transportation fuels, declining petroleum reserves and quest for energy security, there is a renewed interest in Fischer-Tropsch (FT) technology as a viable alternative for the production of liquid fuels from carbonaceous resources (natural gas, coal and biomass). Concern about global warming has also created a special interest in the use of biomass (Biom ass-ToLiquid Fuels, BTL) as a carbon-neutral route to liquid fuels. However, carbon utilization in BTL via traditional biomass gasification is between 25 – 40 % of carbons in the biomass feedstock. This results in poor process economy. Energy input from concentrated solar power (CSP) into BTL can salvage undue large carbon discharge in traditional BTL. The CSP-BTL hybrid not only improves carbon utilization but is also a plausible strategy for solar energy storage

The effect of heavy tars (toluene and naphthalene) on the electrochemical performance of an anode-supported SOFC running on bio-syngas

The effect of heavy tar compounds on the performance of a Ni-YSZ anode supported solid oxide fuel cell was investigated. Both toluene and naphthalene were chosen as model compounds and tested separately with a simulated bio-syngas. Notably, the effect of naphthalene is almost negligible with pure H2 feed to the SOFC, whereas a severe degradation is observed when using a bio-syngas with an H2:CO = 1. The tar compound showed to have a remarkable effect on the inhibition of the WGS shift-reaction, possibly also on the CO direct electro-oxidation at the three-phase-boundary. An interaction through adsorption of naphthalene on nickel catalytic and electrocatalytic active sites is a plausible explanation for observed degradation and strong performance loss. Different sites seem to be involved for H2 and CO electro-oxidation and also with regard to catalytic water gas shift reaction. Finally, heavy tars (C>=10) must be regarded as a poison more than a fuel for SOFC applications, contrarily to lighter compounds such benzene or toluene that can directly reformed within the anode electrode. The presence of naphthalene strongly increases the risk of anode re-oxidation in a syngas stream as CO conversion to H2 is inhibited and also CH4 conversion is blocked

Biomass gasification plant and syngas clean-up system

Gasification is recognized as one of the most promising technologies to convert low quality fuels into more valuable ones. The principal problem related with the use of biomass in gasification processes is the high amount of tar released during the pyrolysis step. It is thus necessary to recover tar and to transform it in lighter combustible gas species such as CH4, CO and H-2. In this work the experimental results of a medium industrial scale plant fed with olive husk and having a capacity of 250 kWt are presented. The gasifier is composed by a up-draft reactor which is followed by a secondary fixed bed reactor filled with alluminium oxide spheres having high porosity dedicated to the tar conversion reactions. The syngas is then used to feed an internal combustion engine with a production of 60 kWe

Analýza procesu zplyňování alternativního paliva (50% odpad, 50% plasty)

The paper presents analysis of alternative fuel gasification with use of flue gas as a gasifying agent. As a result of a process syngas with combustible components (CO, H2, CH4, CnHm) was obtained. Laboratory tests were carried out to determine usability of selected alternative fuel to low-temperature gasification process. Tests were conducted in a laboratory reactor allowing to gasify a fuel sample of appx. 1 g. The experimental stand enables recording of a sample weight loss and syngas composition. The process takes place for fuel samples of a constant weight and different granulation and with a set composition of flue gas used as a gasifying agent. The aim of the laboratory research was to determine the usability of RDF fuel for indirect co-firing in power boilers and to build a knowledge base for industrial-size process by defining the process parameters: kinetics (time for fuel to remain in the reactor), recommended fuel granulation and process temperature.Článek prezentuje analýzu zplyňování alternativního paliva s využitím spalin jako zplyňovacího prostředku. Jako výsledek zplyńovacího procesu “syngas” byly definovány hořlavé složky (CO, H2, CH4, CnHm). Byly provedeny laboratorní testy pro určení použitelnosti vybraného alternativního paliva pro proces zplyňování při nízkých teplotách. Testy byly prováděny v laboratorním reaktoru, který umožnil zplyňovat vzorek paliva o hmotnosti cca. 1 g. Experimentální zařízení umožňuje zaznamenat úbytek hmotnosti vzorku a jeho složení. Proces probíhá u vzorků paliva s konstantní hmotností a s různou granulometrii a se stanoveným složením spalin použitým jako zplyňovací medium. Cílem laboratorního výzkumu bylo zjistit použitelnost paliva RDF pro nepřímé spolu-spalování v energetických kotlích a vytvořit znalostní základnu pro reálný průmyslový proces definováním parametrů procesu: kinetiky (doby setrvání paliva v reaktoru), doporučená granulometrie paliva a teploty procesu

A reverse flow catalytic membrane reactor for the production of syngas: an experimental study

In this paper experimental results are presented for a demonstration unit of a recently proposed novel integrated reactor concept (Smit et. al., 2005) for the partial oxidation of natural gas to syngas (POM), namely a Reverse Flow Catalytic Membrane Reactor (RFCMR). Natural gas has great potential as a feedstock for the production of liquid fuels via the Gas-To-Liquid (GTL) process, but this process has not found widespread application yet, mainly due to the large costs associated with cryogenic air separation and complex heat integratio