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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.

The Closed Ecology Experimental Facilities (CEEF), is designed to simulate material circulation, and is an artificial closed agricultural ecosystem with plants, humans and animals. The first seven-day air circulated confinement experiments using the CEEF were conducted three times. The experiments included psychological monitoring of two crew members named “Eco-nauts”. Even though there was some trouble with the CEEF regarding the atmospheric gases (which one of the Eco-nauts discovered himself), all three experiments were completed without critical problems and both Eco-nauts maintained a stable psychological status. Through the experiments, it was found that the interior environment of the CEEF could fluctuate within short time periods, and that frequent monitoring by the instantaneous and sensitive Face Scale Test allowed scoring of the Eco-nauts' response to such fluctuations.

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.

Closed habitation experiments are to be carried out using Closed Ecology Experiment Facilities (CEEF) from 2005 to 2009. The last target of duration of closed habitation is four months. Preliminary study and testing have been conducted in order to start the closed habitation experiments. In 2004 as the last year of the preliminary test phase for the 2005–2009 experiments, periodical harvesting from staggered cultivation of 23 crops including rice, soybean, peanut, and sugar beet was continued during 103 days. In order to balance with metabolisms of humans (named as “eco-nauts”) and animals, it is necessary to stabilize production of edible and inedible biomass, CO2 uptake and O2 production of crops. Although biomass production decreased rapidly during first five weeks of the 103-day period, it was relatively stable during last ten weeks. Average major foodstuffs in the harvested edible biomass met the requirement of two Eco-nauts although several minor ingredients were insufficient.

In the Closed Ecology Experiment Facilities (CEEF), with integrating the Closed Plantation Experiment Facilities (CPEF) and the Closed Animal Breading & Habitation Facilities (CABHF), closed habitation experiments without material exchange with the outside will be conducted after the 2005 fiscal year. Cultivation experiments of about 30 crops and the integrating test of the material circulation system required for the closed habitation experiments have been performed since 2000 fiscal year. Using data reported in these experiments, material circulation in CEEF is simulated based on the recent operation strategy, and the storage capacity needed for the buffer of an air processing subsystem was estimated. In order for two humans to dwell over 120 days, the storage capacities of the carbon dioxide tank, the oxygen tank, and the waste gas tank in CPEF, and the carbon dioxide tank and the oxygen tank in CABHF are 820 g, 2830 g, 4425 g, 1780 g, and 1792 g, respectively.

The basal metabolism of the Candidate Animal is mainly on energy metabolism that was estimated for future animal breeding in CEEF as preliminary research. The amounts of gas exchange in the respiration and heat production of the Shiba goat (native Japanese goat) were analyzed to predict energy and material flow of the animal breeding system in the Closed Ecology Experiment Facilities (CEEF). Experimental animals were fed Timothy hay or inedible parts of rice cultivated in CEEF. The feces and urine were collected during the 7-day metabolism measurement period after a 2-week preliminary breeding period. The O2 consumption, CO2 production, and CH4 production were measured by a mass spectrometric respiration gas analysis system on the 7th day of the metabolism measurement period. Heat production was also obtained from these data. O2 consumption, CO2 production and CH4 production were 100.3 - 153.8 L, 127.2 - 174.0 L and 5.7 - 10.8 L per day (at 0°C, 0.101MPa), respectively.

Simulation of material circulation for a closed experiment using CEEF consisting of a plant and human system was performed. Initial set of materials contained in CEEF was decided by a decision procedure. Before the closure where the plant system is operated independently, the plant system (CPEF) needs gas exchange of O2 and CO2 with the outside. After the closure where the plant and human system are operated in a cooperation mode with mutual material exchange, no exchange of materials is needed. The closure time corresponds to the longest cultivation period to be cultivated in CPEF.

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.

The closed ecology experiment facility (CEEF) has a small positive pressure control system consisting of rubber buffers and a mechanical subsystem. In the present study, effects of small temperature disturbances caused by changes of surrounding conditions on the pressure control system are investigated experimentally and in numerical simulations. Though solar radiation causes a pressure disturbance in the facility, choosing the proper diameter of ducts which connect the rubber buffers to the modules, the rubber buffers can follow fluctuations of low frequency, like daily atmospheric fluctuations and pressure changes caused by temperature control of the facility’s air conditioners, and can cut off those of high frequency due to changes of environmental conditions.

It is necessary to develop a small positive pressure control system for the closed ecology experiment facility (CEEF) to protect against over-differential pressure loading. In the present study, a numerical method was developed to calculate the quantity of state of the closed module, which is fitted with rubber buffers, for the small positive pressure control system. Experiments to examine the pressure change of the closed module were carried out at CEEF. Comparison of calculated and experimental results showed that the present dynamic simulation is suited to estimating the quantity of state of the closed module.

In CEEF(Closed Ecological Experiment Facility) which is the first Japanese CELSS experiment facility, the ammonia and ammonium nitrate production system is a nitrogen fixation system as a part of nitrogen circulation system. Nitrogen and water which are input materials to the system are processed to produce ammonia water and ammonium nitrate solution as raw materials of fertilizer for plant cultivation. The design basis of the system is to convert 125g/day of nitrogen to ammonia and ammonium nitrate based on the amount of one person's metabolism. Experiment of the system has been carried out and we have studied characteristics of the system.

This waste management process must be capable of treating the various wastes generated within Controlled Ecology Experiment Facilities (CEEF) and operate effectively in and environment in which carbon, oxygen, nitrogen, salts, and other important minerals, exit. The catalytic Wet Oxidation Process (W/O Process) is regarded to be the most feasible candidate process for such waste management. This paper clarifies the performance data and the design data of the actual device. By applying these comparison data, for example, water balance, insoluble part balance, organic part balance, and inorganic balance for CEEF, we were also able to confirm the usefulness and applicability of the actual Wet Oxidation Device.

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.

Compared with other applicable processes such as incineration, the catalytic wet oxidation process is considered to be the most practically applicable waste treatment process for the CELSS. In this report, the quantity of carbon monoxide generated in the wet oxidation process is identified and a measure for carbon monoxide minimization is discussed. As a result of a bench test, it became apparent that a non-negligible quantity of carbon monoxide could be generated in the catalytic wet oxidation process. However, it can be expected that this CO content will be reduced to a safe level by applying the wet oxidation process catalyst reactor to CO oxidation.

In the closed environments such as manned space station, it is necessary to remove contaminant gas to keep a suitable environment. Removal of gaseous contaminants generated from crew, animals, and plants is important function to keep the environment below the allowable level in the Closed Ecology Experiment Facilities (abbreviated as CEEF). CEEF consist of three modules for habitat, animal and plant, the supporting facilities for each module and a plant cultivation facility. CEEF are scheduled to be constructed from 1994 in Aomori Prefecture, northern part of Japan. For designing Trace Contaminant Control Assembly (TCCA) for CEEF, the following six (6) trace contaminants have been selected as major contaminant gas in CEEF; Ammonia (NH3) Methane (CH4) Ethylene (C2H4) Carbon Monoxide (CO) Nitrogen Dioxide (NO2) Sulfur Dioxide (SO2) Ethylene is well-known as an aggressive contaminant to plant growth and maturity.

Selected vegetables for life support are continuously produced in the lunar farming module. Inedible parts of the vegetables are decomposed and provided as the fertilizer elements for the next vegetables. In this report, contained elements in their inedible mass for recyclingare discussed for each of the four vegetables. Elements and concentration of cultural liquid which are required by each vegetable are surveyed as well. Adjustment of decomposition liquid is discussed in view of transforming inedible vegetable to cultural liquid. Authors are proposing wet oxidization as one of the decomposition methods for these inedible parts. Some adjusting sub-system is necessary here, since elements and their concentration in decomposition liquid is not enough to reproduce vegetables. This report aims to clarify the composition of a vegetable production system for an eight-member

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 front half of the nitrogen fixation system, which is one of the subsystems of Controlled Ecological Life Support System (CELSS), or NH3 synthesis loop at atmospheric pressure, was studied. The NH3 separation essential in the loop is discussed. The NH3-PSA method was newly developed, since the NH3-PSA was evaluated best among separation methods from the viewpoints of CELSS criteria. It is essential to retain the H2/N2 ratio in the outlet gas the same as that of the inlet gas to the PSA. From the experimental result of PSA a material balance of the NH3 synthesis loop was calculated. Additionally a material balance of the overall process was calculated by assuming some performances in the down stream sections of the NH3 synthesis loop.

Materials circulating in a closed ecological system are classified as metabolic ones and nonmetabolic ones. Nonmetabolic substances relate to environment constituents and cultural activities. Treatment of these materials are discussed from a view point of CELSS concept. The closed system, CEEF, will be constructed in Japan in the near future. CEEF is an experiment facility with processing capacity of two adult persons, consisting of a plant module, an animal module, a habitat module and supporting facilities for the three modules. The supporting facilities are composed of artificial processors of gases, waters and wastes. The plant module has artificial and natural lighting cultivating sections.