| Lignin has the second largest storage capacity as one of the biomass components, it is distributed in plants massively. It is a clean and renewable energy with a great development potential, so the technology of how to use it has always been concerned widely. However, the study carried on the gasification technology of it is quite few by now. Lignin has a complex structure and a high stability, after being pyrolysis most of the products were conducted to be coke. The carbon conversion and gas yield of the reaction can be promoted by the addition of catalysts. Olivine is one of the commonly used, cheap, wear resistance catalysts during biomass gasification process. Copper slag belonging to industrial waste which is produced during copper smelting is similar to olivine in the chemical composition, and its main mineral is 2FeO-SiO2, Fe3O4 and Ca(Fe,Mg)(SiO3)2.In view of this, a method of catalytic gasification of lignin with catalytic performance of hot copper slag is proposed and mechanism analysis of copper slag in lignin catalytic gasification is also carried on. For developing this process, investigations were conducted in this thesis as follows:Firstly, the effects of catalysts (original copper slag and copper slag), quality of the catalyst and lignin ratio (C/L) and heating rate are determinedt in a TGA analyzer. The results prove that five processes are consisted in the lignin air gasification reaction:drying, preheating, pyrolysis, slowly pyrolysis and gasification. Three distinct peaks existed on the weight loss rate curve respectively, which correspond to the drying, pyrolysis and gasification stage, and the value of them increase gradually. This shows that in the lignin gasification reaction, coke gasification is the main phase. The addition of original copper slag and copper slag can make the lignin weight loss move to the low temperature region and increase the maximum weight loss rate of lignin gasification, copper slag has more obvious effects. Within the experimental range (1 to 2.5), the values of the DTG peaks for pyrolysis and gasification of biomass reach the maximum in the ratio 2. The weight loss curves of lignin move to the high temperature region within the increasing heating rate due to the heat lag caused by rapid heating.Secondly, on basis of the TGA experiments above, the double extrapolation method is used to calculate kinetic parameters of copper slag catalytic gasification, the result shows that the most probable mechanism function is Z-Y-L model, and its activation energy obtained in the pyrolysis and gasification stage were 63.49kJ /mol and 169.66kJ/ mol.At last, for study the hydrogen production characteristic of lignin gasification and reforming, a two-stage fixed bed was investigated for the experimental research on lignin steam gasification. The effects of catalysts, reforming temperature, steam and carrier gas feeding speed on gasification characteristics were determined. The results prove that hydrogen production can be increased through the use of copper slag catalysts and higher reforming temperature.The steam/lignin and carrier gas feeding speed all have a best value, the volume fraction of hydrogen will decrease after it increase at first. By detecting the characteristic of copper slag before and after the reaction, writer infer the chemical change of copper slag in the reforming reaction, which is the Fe3O4 and α-Fe2O3 in copper slag has been reduced to iron in the atmosphere of gasification gas (H2, CO and CH4), and iron is the reason of why the copper slag has catalytic properties. Then the iron change to iron oxides such as FeO by reacting with the water vapor, at last Fe2SiO4 will be conducted after the reaction between FeO and SiO2.
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