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NASA NTRS · 20040120659

Analysis of an algae-based CELSS. Part 1: model development

Holtzapple, M. T.·Little, F. E.·Makela, M. E.·Patterson, C. O.
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Abstract

A steady state chemical model and computer program have been developed for a life support system and applied to trade-off studies. The model is based on human demand for food and oxygen determined from crew metabolic needs. The model includes modules for water recycle, waste treatment, CO2 removal and treatment, and food production. The computer program calculates rates of use and material balance for food. O2, the recycle of human waste and trash, H2O, N2, and food production supply. A simple non-iterative solution for the model has been developed using the steady state rate equations for the chemical reactions. The model and program have been used in system sizing and subsystem trade-off studies of a partially closed life support system.

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Models, ChemicalBioreactorsSpace Flight/instrumentationAlgae/metabolismLife Support Systems/instrumentationEcological Systems, ClosedCarbon Dioxide/chemistryUrineEnergy MetabolismFood, FormulatedSupport, U.S. Gov't, Non-P.H.SWater/chemistry/metabolismMathematicsAmmonia/chemistryFecesWaste Management/instrumentation

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Holtzapple, M. T., Little, F. E., Makela, M. E., Patterson, C. O.. 1989-04-01. Analysis of an algae-based CELSS. Part 1: model development. https://ntrs.nasa.gov/citations/20040120659

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