| Chemical-looping technology has attracted world wide attention,which is the effectual means of clean and efficient utilization of the carbonaceous fuel.It is a novelty flameless combustion technology with oxygen carrier?OC?circulating,which is characterized by inherent CO2 separation.By controlling the ratio of oxygen carrier to feedstock,the chemical-looping combustion?CLC?and chemical-looping gasification?CLG?can be achieved,respectively.Coal,biomass,and carbon-containing solid waste are usually used as fuel.However,the generation,emission and accumulation of industrial solid waste have been on the rise in China.Therefore,it is an effective way to solve the above-mentioned problem through the chemical looping technology to realize industrial solid waste resource utilization.In this thesis,the typical carbon containing solid industrial waste waste activated carbon was selected as fuel and the iron-based synthetic oxygen carrier and red mud were devoted as oxygen carriers.In order to provide basic experimental data support for the resource utilization of industrial solid waste,the reaction characteristics of industrial waste activated carbon chemical-looping process were investigated in a thermogravimetric analyzer and a batch fluidized bed reactor.This paper consisted of three aspects.?1?The effect of different oxygen sources and optimum reaction condition for hydrogen-enriched syngas production from industrial waste activated carbon with Fe4ATP6 as oxygen carrier in chemical-looping gasification were investigated in high-temperature bench fluidized bed reactor.It was demonstrated that Fe4ATP6exhibited good reactivities during CLG process,and it had double effects of catalysis and lattice oxygen providing,which could enhance the carbon conversion rate and the gasification reaction rate.The optimum reaction conditions were 900 oC,steam flow rate of 0.25 g·min-1,OC/C ratio of 1.Under the optimum reaction conditions,55.3%of H2 average concentration,1.09 L·g-1 of H2 yield,1.20 L·g-1 of syngas production and92.15%of carbon conversion were achieved.The reactivity of Fe4ATP6 decreased slightly as a function of ten redox tests.Surface morphology and composition of Fe4ATP6 were analyzed by SEM and XRD,respectively.The results indicated that the structure of Fe4ATP6 changed significantly,while its particle size decreased slightly.In addition,unreactive iron silicates were found to be generated in Fe4ATP6 during the ten redox tests.?2?The reactivity behavior of industrial waste activated carbon chemical-looping combustion with red mud as oxygen carrier was examined in a bench fluidized bed reactor.The red mud could be used as oxygen carrier in CLC process,and its reactivity was affected by the calcination temperature,which presented good reactivity and pore structure after being calcined at 900 oC.The carbon conversion rate and gasification rate in the CLC process could be enhanced significantly by the catalytic function of Na in red mud,which was beneficial to the full conversion of fuel.81.51%of CO2 content,77.27%of combustion efficiency and 45 min of T95 time reached at the optimum temperature of 875 oC.?3?To further promote reactivity of red mud oxygen carrier,the red mud oxygen carrier modified by CuO?Cu0.5RM1,Cu1RM1?was prepared through impregnation method.The SEM-EDS mapping showed that impregnation method was a desirable approach for preparing quantitative CuO-modified red mud oxygen carriers.CuO-modified red mud oxygen carriers were demonstrated to act as both CLC oxygen carrier and chemical looping with oxygen uncoupling oxygen carrier.Furthermore,waste activated carbon conversion rate and CO2 concentration were significantly enhanced in comparison to pure red mud oxygen carriers.Additionally,the amount of CuO modification affected the reactivity of the oxygen carrier.It was found that Cu1RM1,due to the high CuO loading,performed higher reactivity than Cu0.5RM1.At the optimum temperature of 875 oC,the CO2 average concentration of 92.9%,the combustion efficiency of 93.0%and the residence time(T95)of 28 min were presented.Moreover,Cu1RM1 had a good stability during the ten-redox tests. |
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