Study On Preparation And Performance Of Cu-based Oxygen Carriers For Chemical Looping With Gasification

Nowdays, chemical looping gasification is a promising gasification technology. It combines tranditional gasification technology with chemical looping technology, which can further reduce energy lose in resources conversion process.9 kinds of oxygen carriers were prepared by sol-gel method, and non-isothermal method was used to research their oxygen releasing temperature and speed on a fixed-bed reactor, results show that 5%Co3O4/CuO and 5%NiO/CuO have the lowest reaction temperature and fastest reaction rate. The reaction dynamics of the oxygen carriers were analyzed by isothermal method, by caculating, the mechanism function of oxygen releasing reaction is the J-M-A function, which described as G(a)= [-ln(1-α)]1/2, and the size relation of activation energy can be described as 5%Co3O4/CuO<5%NiO/CuO<5%Fe2O3/CuO<5%Mn3O4/CuO< 5%MgO/CuO<CuO<5%CaO/CuO<5%Na2O/CuO<5%K2O/CuO.The water chemical-looping gasification and co-gasification of coal and biomass were researched on a gasification furnace. Results show that in water gasification and chemical-looping gasification experiments, the releasing rate and production of H2 is the highest. Compared with 5%NiO/CuO,5%Co3O4/CuO has a better reactivity and gasification result in chemical-looping gasification of coal and biomass. Compared with water gasification of coal and biomass, the chemical-looping gasification provides a higher production of H2 and CO. The water co-gasification of coal and biomass has an excellent cooperative effect in regard to H2 and CO production. Both production and cooperative effect of H2 and CO is more outstanding in chemical-looping co-gasification when compared with the water co-gasification, the production of H2 and CO has increased by 15.38% and 38.89%, respectively. Also, the C conversion rate of co-gasification is higher than that of separate gasification.