Browsing by Author "Taylor, Dale"
Now showing 1 - 2 of 2
- Results Per Page
- Sort Options
Item Ceramic Oxygen Generator: A Method for Extracting High Pressure, High Purity Oxygen from Spacecraft Cabin Air.(2023 International Conference on Environmental Systems, 2023-07-16) Graf, John; Taylor, Dale; Tylka, JonIon Transport Membranes (ITMs) are ceramic membranes permeable to oxygen and only oxygen. They are capable of extracting pure oxygen from air, or other gaseous process streams that contain oxygen. For several decades, ITMs have been the subject of research: particularly for the supply of ultra-high purity oxygen and as a method for providing oxygen to zero emission power plants. ITMs have not been put into widespread practice. ITM devices have not been qualified for human spaceflight, and they have not been used to supply medical oxygen to hospitals. ITM oxygen generators have not seen widespread use because previous ITM systems suffered low production rates and high energy consumption. NASA, in partnership with American Oxygen, has developed a ceramic oxygen generator (COG) with substantially higher oxygen production rates, and substantially lower energy consumption than earlier systems. Three key elements are essential to increased production and improved energy efficiency: the cell stack, the thermal management system, and the oxygen delivery system. This paper describes recent improvements in these three elements, along with results of testing that demonstrates unprecedented system level performance. Two forms of this technology are in development: one form produces oxygen at pressures up to 1 MPa, another version produces oxygen at pressures as high as 20 MPa. The prototype described in this paper is designed for 1 MPa operations, but advances in cell stack manufacture, thermal management, and oxygen delivery apply to high pressure applications.Item Solid State Electrochemical Oxygen Separation and Compression(49th International Conference on Environmental Systems, 2019-07-07) Reisert, Michael; Aphale, Ashish; Taylor, Dale; Graf, John; Singh, Prabhakar; Hu, Boxun; Heo, Su Jeong; Hong, JunsungCeramic and solid-state electrochemical oxygen separation and compression systems offer the ease of producing high purity and high pressure oxygen from a variety of gaseous streams representative of ambient and constrained system exposure conditions (terrestrial and space). The electrochemical cells utilize exclusive oxygen ion conducting ceramic membranes (doped fluorites) and operate in a 550-850 °C temperature range. Advanced perovskites synthesized from non-noble and non-strategic materials serve as electrodes for both oxygen reduction and evolution. A number of electrochemical cells, connected in series using dense, electronically-conducting perovskite interconnects form the basis of a “cell stack” for increased oxygen production. The robust solid-state device provides a means of oxygen separation/compression, operating favorably in environments without reducing atmospheres (unlike terrestrial fuel/electrolysis cells). Thermochemical-electrochemical principles for oxygen separation and compression will be discussed. Materials for the construction of cells and stack along with fabrication techniques will be examined and the basis for material selection will be described. Approaches for the electrochemical performance improvement will also be discussed.