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Deng, Shuguang

Publications and source records attributed to Deng, Shuguang.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Sorbent-based oxygen separation with YBC114 for energy storage systems

In our report we aimed to design, build, and evaluate an oxygen separation system to provide an inert sweep gas with low oxygen partial pressure (pO2) to redox-active thermochemical energy conversion reactors for a range of applications, including two-step redox cycles for thermochemical energy storage, water splitting, and carbon-dioxide splitting. The separation is based on an oxygen-selective sorbent, YBaCo4O7+δ (YBC114), which has excellent oxygen sorption and desorption properties demonstrated in our previous work. The oxygen separation performance of YBC114 was comprehensively studied by thermogravimetric analysis, sorption breakthrough experiments, and temperature swing sorption - desorption cycles. The results reveal that YBC114 can produce inert sweep gas with an oxygen concentration of less than 100 ppmv for at least 20 min during the thermal swing adsorption (TSA) cycle with the current sorption bed configuration, and the performance is consistent from cycle to cycle. The optimal sorption and desorption temperatures for the TSA process with YBC114 are determined to be 300 °C and 500 °C, respectively. Although challenges remain for the current separation system (e.g., high sorption temperature and slow kinetics), this study demonstrates the potential to use the oxygen-selective sorbent to produce an inert sweep gas, the feasibility of the oxygen separation concept, and guides new sorbent material development to make this application economically practical. A simple procedure is described for designing the YBC114 oxygen separation process.

42 ENGINEERING↗
DOE OSTI2020

Hydrothermal liquefaction of Cyanidioschyzon merolae and Salicornia bigelovii Torr.: The interaction effect on product distribution and chemistry

Hydrothermal liquefaction (HTL) has proven to be a promising technology for processing wet biomass into valuable biofuel intermediates. We investigated the influence of HTL process parameters on the individual and co-liquefaction of Salicornia bigelovii Torr. (SL) and Cyanidioschyzon merolae (CM) biomass and their respective product properties and characteristics. SL and CM biomasses were subjected to HTL conditions of process temperatures (250–350 °C), 10 wt% solid loading, 30 min reaction time, and co-liquefaction ratios (80–20, 50–50, 20–80, CM-SL, respectively). The individual maximum HTL biocrude yields for CM (34.63 wt%) and SL (7.63 wt%) were obtained at 300 °C. In both cases, biocrude oils had a higher carbon and hydrogen content relative to those of the original biomass. The HHV (higher heating value) values for the biocrude samples ranged from 24.2 to 33.12 MJ/kg, which were significantly higher than those of the original biomasses. A positive synergistic effect was observed during the co-liquefaction of two biomasses, where the experimental yield of biocrude oil was higher than the theoretical value. During the co-liquefaction experiments, a maximum biocrude yield of 32.95 wt% was obtained at 300 °C and 80–20 CM-SL biomass mix ratio. Co-liquefaction led to an increase in the energy content of the co-liquefied biocrude oil and a higher energy recovery rate. Finally, the properties of HTL products and biomasses were determined with TGA, CHN elemental analyzer, GC/MS, bomb calorimeter, HACH Spectrophotometer, and ICP OES.

09 BIOMASS FUELS↗