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The Closed Ecology Experiment Facilities (CEEF) were installed to collect data for estimation of transfer of radionuclides from atmosphere to humans in the ecosystem. The first target among the radio-nuclides is 14C. In order to validate function of material circulation in an experimental system constructed in the CEEF, circulation of air constituents, water and materials in waste was demonstrated connecting the Closed Plant Experiment Facility (CPEF) and the Closed Animal and Human habitation Experiment Facility (CAHEF) of the CEEF, since 2005 to 2007. The CPEF has a Plant Cultivation Module (PCM), which comprises of three plant chambers illuminated solely by artificial lighting, one plant chamber illuminated by both natural and artificial lighting, a space for preparation, and an airlock, and a physical/chemical material circulation system.

This paper introduces a concept and a design to supply paper products for an earth based Advanced Life Support System (ALSS) test bed and it shows some results of paper production trials on the ALSS using inedible biomass. Rice plants (i.e. straw and roots), and soybean stems were pulped by boiling and/or alkali soaking and a mechanical processing method. Paper could be produced from both and exhibited different characteristics. Paper with quality suitable for hygienic tissue could be obtained and very absorbent paper was also possible. A rapid pulping method without a chemical process was also investigated. A potential for reducing chemical consumption, liquid waste and labor cost of paper production in the ALSS was demonstrated.

In the Closed Ecology Experiment Facilities (CEEF), waste materials such as plant inedible parts, feces and urine of animal and human, and garbage are to be decomposed to inorganic materials by a physical and chemical (P/C) process; Wet Oxidation (W/O). It is known that significant part of nitrogen (N) in the waste materials is reduced to gaseous nitrogen (N2) through W/O process. There is also some deposition of minerals such as iron (Fe) and phosphorous (P) through W/O process. Nitrogen Fixation Subsystem (NFS) produces ammonia (NH3) which is one of end products of NFS, from N2 separated from module air and hydrogen (H2) derived from electrolyses of water, and also produces nitrate (HNO3) from a part of the NH3 and oxygen (O2) derived from electrolyses of water. As another end product of NFS, ammonium nitrate (NH4NO3) is produced from the HNO3 and a part of the NH3.

In order to verify the material circulation design for a Closed Ecology Experiment Facilities, CEEF, the organic element analysis of edible and inedible parts of the major candidate plants (rice, soybean, sesame and komatsuna (Brassica campestris)) has been carried out experimentally and by using food analysis data. In the experiment, rice, soybean and sesame were cultivated by hydroponics and soil culture for this purpose. The organic element analysis data from the food analysis data were made using empirical chemical equations formulated as to major nutriments by Volk and Rummel. The experimental results showed good agreement with those obtained from the food analysis data. Komatsuna has high nitrogen content. Inedible parts of rice, soybean and sesame have almost the same constituent ratio. The edible part of soybean contains five times as much nitrogen as its inedible part. Rice shows no significant difference between the edible and inedible parts.

Construction of Closed Ecology Experiment Facilities (CEEF) is started in Rokkasho village of Aomori prefecture, the northern part of Honshu island in Japan. CEEF consist of Closed Plant Experiment Facility (CPEF) and Closed Geo-Hydrosphere Experiment Facility (CGEF) with capability to simulate ecological systems containing plants, animals, human, trees and sea living things. These biospecies are selected according to experimental plans and are maintained their lives in controlled environments. Recyclings of materials circulating in the closed system of CEEF are made mainly utilizing physical chemical treatments. The construction of CEEF will be completed by 1998. This paper mainly describes design of CPEF.

Nitrogen Fixation Systems(NFS) suitable for plant cultivation in a closed environment have been studied through experimental verification. The system is composed of physico-chemical processes only. Nitrogen gas and water are fed into the system as raw materials,and ammonia and ammonium nitrate solution are produced as final products, which are utilized as main fertilizers in plant cultivation. Each elemental chemical process in NFS is selected with regard to unique design criteria concerning safety, energy effectiveness, compactness and reliability. An experimental apparatus for important unit processes has been made for the purpose of verifying process data. A detail design for nitrogen fixation facilities, planned for construction as the first Japanese CELSS laboratory, was carried out.

The recovery of important minerals, salt (NaCI) and potassium (K), in a closed system, namely CELSS is discussed. NaCI is needed for humans, but is potentially harmful to plants. Salt is recovered after wet oxidation of urine. Since Na and K have similar chemical and physical properties, their recovery or separation may require sophisticated methods. Na, CI and K ions are separated from other ions by electrodialysis with univalent selective ion-exchange membranes and then NaCI is obtained separately by a crystalization process. Preliminary experiment on crystalization of NaCI-KCl mixed solutions showed a good separation result.