Thesis (M.S.)--Ohio University, August, 1987. / Title from PDF t.p.

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

The last couple of decades have seen entrained-flow gasification of black liquor (BL) undergo an incremental process of technical development as an alternative to combustion in a recovery boiler. The ability of the technology to combine chemical recovery with the production of clean syngas renders it a promising candidate for the transformation of chemical pulp mills into integrated forest biorefineries. However, techno-economic assessments have shown that blending BL with the more easily transportable pyrolysis oil (PO) can not only increase the system efficiency for methanol production but remove a significant roadblock to development by partially decoupling production capacity from limitations on black liquor availability. The verification and study of catalytic co-gasification in an industrially-relative scale can yield both scientifically interesting and practically useful results, yet it is a costly and time-consuming enterprise. The expense and time involved can be significantly reduced by performing thermodynamic equilibrium calculations using a model that has been validated with relevant experimental data. The main objective of this thesis was to study, understand, quantify and compare the gasification behaviour and process performance of black liquor and pyrolysis oil blends in pilot-scale. A secondary objective of this work was to demonstrate and assess the usefulness and accuracy of unconstrained thermodynamic equilibrium modelling as a tool for studying and predicting the characteristics of alkali-impregnated biomass entrained-flow gasification. The co-gasification of BL/PO blends was studied at the 3 MWth LTU Green Fuels pilot plant in a series of experimental studies between June 2015 and April 2016. The results of the studies showed that the blending of black liquor with the more energy rich pyrolysis oil increased the energetic efficiency of the BLG process without adversely affecting carbon conversion. The effect of blend ratio and reactor temperature on the gasification performance of PO and BL blends with up to 20 wt% PO was studied in order to assess the impact of alkali-dilution in fuel on the conversion characteristics. In addition to unblended BL, three blends with PO/BL ratios of 10/90, 15/85 and 20/80 wt% were gasified at a constant load of 2.75 MWth. The decrease in fuel inorganic content with increasing PO fraction resulted in more dilute green liquor (GL) and a greater portion of the feedstock carbon ended up in syngas as CO. As a consequence, the cold gas efficiency increased by about 5%-units. Carbon conversion was in the range 98.8-99.5% and did not vary systematically with either fuel composition or temperature. The validation of thermodynamic equilibrium simulation of black liquor and pyrolysis co-gasifications with experimental data revealed the need to be mindful of errors and uncertainities in fuel composition that can influence predictions of equilibrium temperature. However, provided due care is to taken to ensure the use of accurate fuel composition data, unconstrained TEMs can serve as a robust and useful tool for simulating catalytic entrained-flow gasification of biomass-based feedstocks. / LTU Biosyngas (Catalytic Gasification)

Syngas is an interesting energy source for metallurgical processes, as an energy carrier syngas is an efficient way of utilizing the energy in biomass. Utilizing syngas in fuming processes as a carbon source instead of coal was an approach to minimize carbon dioxide emissions produced in the fuming process. In the fuming process, secondary materials are processed to improve the extraction of copper, lead, and zinc.  The objective of this project was to find a suitable biomass and gasification agent that result in syngas with a high percentage of carbon monoxide and a low percentage of carbon dioxide. Because of the high need of carbon in the fuming process, syngas could be a suitable reduction agent. The most efficient thermo-chemical process for syngas production from biomass is gasification.  The investigated biomass where sawdust, wood, and a co-gasification with a percentage of peat. The gasification agents investigated where carbon dioxide, oxygen, air, and hydrogen. This was investigated by using FactSage8.1 to simulate the gasification and co-gasification of chosen biomasses and gasification agents. Stoichiometric calculations of the fuels and gasification agents were done to get the correct reduction and combustion reactions.  The results from the simulations showed that carbon dioxide was the best gasification agent and gasifying sawdust alone results in the highest simulated levels of carbon monoxide in the gasification temperature between 1000 to 1200 ᵒC.  Other studies showed that biomass gasification with carbon dioxide or a mixture of at least 60 percent of carbon dioxide as a gasification agent was a promising way for energy production and lowering carbon dioxide emissions. It also shows a correlation between increasing carbon dioxide as a gasification agent and higher level of carbon monoxide in the produced syngas. Other studies implied that the maximum level of carbon dioxide that results in the maximum fraction of carbon monoxide and methane was 60 percent.  Each gasification agent investigated have advantages and disadvantages, they lead to different gas composition, by-products, and heating value, which gasification agent to use depends on the result wanted. Carbon dioxide was the gasification agent that shows the best result in a simulated environment, but the same result cannot be guaranteed in real-life experiments, and discrepancies are to be expected. Further study in form of a real-life experiment are needed to compare with the simulated results, as the effects of ash forming elements and test of gasifier are needed.

Thesis (M.E.)--University of Canterbury, 2008. / Typescript (photocopy). Includes bibliographical references (p. 194-196). Also available via the World Wide Web.

The topic of master´s thesis is atmosferic gasification of biomass by the addition of oxygen and steam. The theoretical part is devoted to the description of biomass, process of gasification, kinds of gasification reactor and product gas. Further experiments are devised depending on the gasification medium and output temperature. In this case, the key aspect is the steam addition control. In the practical part, these experiments are performed in a fluidized bed reactor. Resulting values from samples of gas and tar are subsequently processed and evaluated.

No description available.

No description available.

Call number: LD2668 .T4 1984 N46 / Master of Science