General application conditions of the solid phase extraction with porous polystyrene polymer cartridges, Sep-Pak PS-1 and PS-2, were investigated.
The PS-1 and PS-2 could adsorb various organic compounds from water in several ten times to several hundred times in comparison with tC₁₈ which is a conventional octadecylsilane adsorbent. The adsorbable volumes for the solution to PS-2 are more than ca. 70% of those to PS-1. The adsorbable volumes for single component solution of 44 compounds to the PS-1 cartridge could be shown by the function of the concentration C and the solubility in water S. The adsorbed compounds could desorb with 3ml acetone from PS-1 and PS-2. From these results, the procedure for deciding the concentration conditions for simultaneous analysis or bioassay test of various trace organic compounds in water samples was proposed. It was confirmed that various trace compounds in the river water samples could be concentrated simultaneously by the proposed conditions.

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Recently, environment-friendly public works are demanded. We evaluated an advantage of the utilization of rainwater and treated domestic wastewater in urban area. The rainwater utilization is the use of rainfall on the roofs, walls and collected runoff storm water in the storm water reservoir for flood controls. In the reuse of treated domestic wastewater, wastewater from the raw sewage is not reused. That is “Domestic Water Recycling System”. We evaluated the amount of conserved drinking water and the amount of decreased final effluent polluted matters by the unused water resources utilization. And we estimated the amount of carbon dioxide emission by the construction and operation of the unused water utilization system. Water self-support system (the use of rainfall on the roofs, walls and the domestic water recycling system) are effective in the decrease of the resources consumption and the environmental loads.

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The objectives of this research were to evaluate the optimum treatment conditions of the three phase fluidized bed with draft tube for the aquaculture wastewater treatment, and thereby reduce the volume of treatment process. Three phase fluidized bed process with draft tube had more effective than traditional methods for reducing ammonia in the culture system, which can results in the reduction of the water treatment tank volume. When Oreochromis niloticus was reared, the unit production of pollutants were 0.07g NH₄⁺-N · kg fish^-1 · d^-1 and 0.06g PO₄^3--P · kg fish^-1 · d^-1, and sludge production rate was 0.39g SS · kg fish^-1 · d^-1. The maximum removal rates of COD and ammonia were 1,200 mg · l^-1 · d^-1 and 488 mg · l^-1 · d^-1, respectively. Ammonia removal rates were more than 90% during HRT of 1hours. In the three phase fluidized bed, the volume of water treatment tank could be calculated from an empirical equation by using the relationship between the influent COD to NH₄⁺-N ratio (C/N), media concentration (C_m, g · l^-1), influent ammonia nitrogen concentration (N₁, mg · l^-1), effluent ammonia nitrogen concentration (N_e, mg · l^-1), and influent flowrate (Q, m³ · hr^-1). The empirical equation from was obtained from this study.
V=10^11.7507 C/N^-1.2330 C_m^-6.5715 N_i^1.5091 N_e^-1.8489 Q

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To establish a foam separation technique using proteins as a foaming reagent, it is important to know the foaming characteristics of various protein solutions and to demonstrate the effective application of these proteins. In this study, the effects of pH and coexistent substances on the foam formation of various proteins were examined.
The results are as follows.
(1) The foaming capacity of globular proteins such as casein, hemoglobin, soy protein, and albumin was enhanced in both strong acid and alkaline solutions. In contrast, gelatin, which is a fibrous protein, had only a slight dependency on pH.
(2) The foam formation of proteins varied with the differences of cations in the solution. The enhanced potential were Na⁺=K⁺>Mg²⁺>Sr²⁺>>Ca²⁺ in order. Anions had no effect on foaming capacity.
(3) The foaming capacity of casein was elevated with the addition of LAS (sodium linear-dosecylbenzenesulfonate). In contrast, the capacity of casein was lowered by the presence of SDS (sodium dodecyl suophate).
(4) Globular proteins showed denaturation, dissociation and association with pH and coexistent substances, and these change affected foam formation.
It is possible to generate the optimum amount of proteinaceous foam by taking advantage of each protein's unique characteristics.

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In the present study, the adsorption of cadmium on Mn₂O₃ in aqueous solution was investigated. The Mn₂O₃ was prepared by heating MnCO₃ at 300∼800°C for 4.5 hours.
The findings of the present study are as follows:
(1) The Mn₂O₃ showed the ability to adsorb and concentrate cadmium from aqueous solution to levels reaching 23.2∼46.6mg · g^-1 under the following conditions : heating temperature=300°C, solution pH=7, and cadmium concentration=1∼100mg · l^-1. The surface area of the Mn₂O₃ was 50m² · g^-1.
(2) The cadmium was eluted from the Mn₂O₃ by adding 0.5mol · l^-1 HNO₃, and the adsorption ability of the Mn₂O₃ recovered to nearly the previous level.
(3) We attempted to remove cadmium from a sample (1l) of mining effluent (0.117mg · l^-1 Cd) from the Yoshino mine in Akita prefecture, Japan using Mn₂O₃ (1g). The results showed that the cadmium concentration of the treated effluent decreased to under 0.001mg · l^-1 in 2.5 hours.

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In order to use protein as a chemical to bring about effective foam separation, it is necessary to understand foaming capacity and the factors that affect this capacity. In this study, the effect of various protein solutions on foaming capacity were measured using a bubbling column. The test compounds were casein, soy protein, albumin, hemoglobin, gelatin, and LAS.
The foaming capacity of a protein and a surfactant were evaluated by determining the height of the foam at the time of splitting or decaying within the bubbling column under constant conditions of air flow, volume of test solution, and water temperature. The most effective protein was casein followed by hemoglobin, soy protein, gelatin, and albumin. The capacity of casein was comparable to that of LAS. Under appropriate conditions, 0.3l-air · min^-1, 100ml sample, 20°C, and pH6.9, the concentrations of casein and LAS required to make a foam height of 30cm (column diameter, 2.6cm) were 4.4mg · l^-1 and 4.6mg · l^-1, respectively.

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