Chemical looping gasification characteristics and kinetic analysis of Chlorella and its organic components

[Display omitted] •Chemical looping gasification (CLG) behavior of model components of microalgae was explored.•Product distribution and LHV of different components during CLG were determined.•Kinetic parameters on model compound and algae CLG were solved by the KAS method.•The difference of simulated and real algae on the results of CLG was analyzed. Chemical looping gasification (CLG) characteristics and kinetic analysis of Chlorella (CHL), simulated Chlorella (V-CHL) and medium-chain triglycerides (MCT) were investigated using a thermogravimetric analyzer coupled with an online mass spectrometer. The apparent activation energy was obtained via Kissinger-Akahira-Sunose (KAS) method. In the result of the weightless behavior, the addition of oxygen carrier inhibited the decomposition of V-CHL at lower temperatures but promoted its decomposition at high temperatures. The values of chemical looping process characteristic parameters showed that a 10 wt% oxygen carrier would maximize the release of volatile products in the CLG of MCT, with 5.12 × 10−6 %·min−1·oC−3. Oxygen carriers also affected gaseous products. The LHV of gaseous products of CHL reached the largest when the oxygen carrier was 10 wt%, which was 8.13 MJ/m3. And the gaseous product of MCT had the largest LHV with 30 wt% oxygen carrier, which was 8.83 MJ/m3. According to the kinetic analysis, the minimum value of apparent activation energy of MCT chemical looping gasification was 89.54 kJ·mol−1 with the oxygen carrier of 30 wt%, which was 50% less than that of MCT pyrolysis. And the minimum value for V-CHL was obtained when the mass fraction of Fe2O3 was 50 wt%. This paper could provide a reference for the choice of algae, the design of reactors, and the targeted regulation of the gaseous product for the algae CLG process.