Some processes in mineral processing contain several kinds of micro-processes that mean microscopic phenomena e.g. in flotation process the thinning process of the liquid film between an air bubble and the mineral particle or the turbulent motion and the collision of mineral particles with air bubbles. In this review, however, micro-processes have been defined as processes produced by turbulent transport phenomena.
The studies about the micro-processes have been recently developed and progressed. Then the micro-processes contained in the typical three unit operations, that is flotation, classification and thickening processes were reviewed. But a process can not consist of only micro-processes and it contains macroscopic processes. Then in this review at first the macroscopic hydrodynamic researches for the flotation process were summarized. The microscopic hydrodynamic studies for the flotation process were secondly reviewed.
In this section methods of the measurement of turbulent characteristics were described especially about electrode reaction methods and image sensor methods. Then the turbulent characteristics, that is fluctuating velocitiesenergy spectra were explained in order to analyze the micro-processes. Kolmogoroff's the ry has bee, nv aellsooc iatpyp clioerdre tloa tsioonlvse athned problems of dispersion of air bubbles or detachment of mineral particles from air bubbles since the turbulent fields in flotation machines can be regarded as at least locally isotropic turbulent fields.(to be continued)

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Until around 1950, the consumption of lithium and its compounds was relatively small in industry where the utilization of lithium was limited to manufacturing glass, ceramics, metal-alloy and some other minor materials. However, in the 1950's, the demand of ⁶ Li increased in the production of nuclear weapons resulting in a large scale production and stock-pile of lithium in 1957. Further, the oil-shock in the late 1.973 promoted battery technology for electric vehicles and energy storage batteries in both of which lithium batteries will be used.
In as much as the resources of crude oils and coals are limited, we have to seek other sources of energies. The study of nuclear fusion technology to obtain our future energy predicts that the nuclear fusion energy will be available commercially in the early twenty first century, although the technology is yet to develop. Liquid lithium is necessary for the heat transfer medium and coolant surrounding the reactor cores. Lithium is also an essential element to supply tritium in the fusion reaction of deuterium and tritium to yiel the energy.
The importance of lithium is paramount to our current and future energy problems. We ought to have a firm information on the natural resources of lithium and its compounds. Therefore, this paper describes the resources, and the current demands and usages of lithium in the world, and discuss the future application of lithium as an energy supplying element.

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In order to solve water pollution problems in abandoned mines, one of the authors has tried to analyze the behavior of ground water flowing through the underground in mine area based on the Darcv's flow in homogeneous media. This analysis has carried out on a certain model by using the finite element method. Although the analysis is annlicahlv as limo ac the model is simple, there may be difficult to apply universally since the more the model iscomplex. the vaster the calculation becomes.
This paper deals with the solving method of that problem by using both the finite element method and Fourier series By this method, analysis of the boundary value problems becomes easy and moreover the accuracy of the analvsis is improved and calculating time of a computer can be shortened.

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First, the pre-mining pressures in the coal burst area of Miike mine are investigated by measuring the strains on the bottom surfaces of. borehole, drilled in the roof, by the stress-relief technique. It is found that the vertical normal stress, equivalent to the weight of overburden, acts on the coal seam and both of the horizontal normal stresses are nearly equal to the half of the vertical normal stress. Secondary, the distribution of the pressure, induced by longwall mining, is examinated by the test drilling method developed in Germany. Analyzing the volume of drillings and the frequency of-rock noise, reached our ears during the test drilling, as shown in Fig. 6, the existence of unusual additional pressure in the coal seam surrounding the mined area is concretely found out, and it is pointed out that this unusual pressure is ascribed to the behavior of the rigid hangingwall consisted of the thick sandstones.
The effect of the de-stress drilling is practically studied by examining the relation between the occurrence of coal burst and the record of the drilling. It is found that the hazard of coal burst at the longwall face can be removed by the effective parallel drilling, 100mm diameer, with the constant interval, 8m, of which the drillings is over 600 liters/m during the drilling in the high-pressure zone, 5-20m distant from the rise side entry, and the averaged frequency of the rock noise is caught over 2 times/m as shown in Fig. 7.

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In this paper a one-dimensional fully established annular flow analysis on a drag coefficient of the hindered-settling cylindrical capsule could be developed and compared with the results of the boundary layer theory on a drag coefficient of the freely-suspended capsuleas described before and experimental results for various factors of capsule which were falling through transparent and vertical tube filled with water.
A drag coefficient could be proved hydrodynamically as follows;C_ds {1-(l/2/d-1) ²} +16l (1/2/d-1)(3-1/d/2)/Rem {1n (1/2/d)(1/2/d+1)-(1/2/d+1)-(1/2/d+1)-(1/2/d-1)}
d;diameter of capsule
D;diameter of pipe
d;the capsule/pipe diameter
ν;kinematic viscosity of the fluid
T;the capsule length/diameter
Rem;Reynolds number Usmd/v
Usm;superficial mean velocity of the hindered-settling capsule
A drag coefficient characteristics curve obtained from the above equation could be applicable for the characteristics number 0.02<l/(1/d-1) ²Rem<0.08.

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The authors achieved experimental studies on the influence of various factors such as pipediameter (D), pipe inclination (θ), pipe length (L), physical properties of solids and conveying fluid etc. on lifting capability and efficiency, and also tried to develop a practical calculation method for lifting volume in both two phase and three phase flow, based on the studies of Kawashima and Noda et al of Tohoku Univ.
The results are summarized as follows.
(1) The bentonite water (II)(γm=1030kg/m) showed a higher lifted volume of solids compared to pure water, especially in inclined pipe (θ=50°).
(2) The basic data in two phase flow were satisfactorily arranged by the relation between 1-f_L2 (X)/σ3/5 and Vgo/√2gL which was presented by Kawashima et al, considering the specific volume of conveying fluid. Consequently, the calculated values for lifting volume of liquid agreed well with the experimental values.
(3) Concerning three phase flow, the following empirical equation was obtained between the averaged volumetric ratio of liquid f_L2 (x) in two phase flow and that of liquid-solid f_L3 (X') in three phase flow.
f_L3 (X')/fL2 (X) = {1-0.094 (ds/D)-0.02} Frg0.031 (DS/D)-0.20 {1+α(154.32β+1.79)}/1-Cv (γs/γm-1)
Here,
α=1-2θ/π, β=γm/γω(γm/γω-1)
Consequently, our experimental results agreed approximately with, the calculated values obtained by the aboved equation, in pract i cal range.(4) The lifting efficiency of liquid and solids was calculated from the experimental results. As a result, the lifting efficiency for liquid was 50-60% and that for solids 8-12% in maximum.

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In barite-water system, the concentrations of constituent ions of the mineral are kept constant over a wide pH range of aqueous solution except strong acidic and alkaline sides. When an equivalencepoint (EP) is defined as the condition at which any selected pair of positive and negative ions have equivalent concentrations, EP (BaOH⁺, HSO^-₄) was pH 7. 6. The EP coincides with IEP (aq) which denotes the condition at zero point of total electric charge of chemical species concerning constituent ions of the mineral. Hydrolysis of surface barium or sulfate ionic species on barite is regulated in accordance with the degree of deviation of pH value from the EP. Flotation behaviour of barite with DAA depended upon the surface hydrolysis. Floatability of barite with SDS was very good over a wide pH range and was not affected by the surface hydrolysis. Consequently, the adsorption mechanism of SDS must be chemical, and that was confirmed by the solubilityproduct of barium dodecyl sulfate.
In calcite-water system, the concentrations of chemical species concerning constituent ions of the mineral are remarkably affected by pH valueof aqueous solution. In this case, surface calcium or carbonate ionic species hydrolyze inaccordance with the degree of deviation of pH value from the IEP (aq). The floatability of calcite with DAA and SDS was affected by the surface hydrolysis. An IEP (aq) of calcite-water system is affected by P_CO2 of gas phase in contact with the system, and also, the system is needed long time for attaining to equilibrium with atmosphere, (P_CO2= 10^-3.5a tm). An IEP (aq) of the system shows a pH value between pH 10.00 and pH 8.35 through the process attaining to the equilibrium. Thus results of measurements of i. e. p.would vary with experimental conditions and methods of measurement etc.
Flotation behaviour of scheelite with DAA and SDS as a function of pH value was closely related to variation of the zeta potential.

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Hydrogen reduction of nickel from an aqueous ammoniacal solution was studied kinetically. The rate curves of the reductive reactions seemed to essentially consist of three distinctstages. The reaction rate of the first stage, which was characteristic of the reaction when small amounts of ferrous sulfate or nickel seed are used, was of the first order with respect to both the partial pressure of hydrogen gas and the concentration of ferrous sulfate added. This reaction was controlled by a chemical reaction having an activation energy of 22.2 kcal/mol. When larger amounts of nickel seed or ferrous sulfate together with anthraquinone were used, the first stage became extremely short. Consequently the reaction seemed to begin with the second stage. This second stage was characterized by a zeroth order reaction with respect to the concentration of nickel. The reaction rate of this stage was of the first order with respect to the partial pressure of hydrogen, having an activation energy of 4.2 kcal/mol. The reaction during this stage may have been controlled by the absorption of hydrogen gas through the boundary layer between the gaseous and liquid phases. The activation energy of the third stage was found to be 11.3 kcal/mol. From observations with a scanning electron microscope during this stage, the increased particle size of reduced nickel may have led to insufficient active sites on the nickel particles, resulting inadecline in the reaction rate.

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thermal dissociation pressure of 2TiO₂·EAs₂O₅ and 2CuO·EAs₂O₅ prepared by making a precipitate for each arsenate in a wet method have been measured using transpiration technique.
The dissociation temperature of these arsenates has been measured roughly by T.G.A. These dissociation reactions have been studied by X-ray analysis. The main results obtained are as follows.
1) The dissociation of 2TiO₂.As₂O₅ and. 2CuO. As₂0₅ proceeds in accordance with the following reactions.
2TiO₂·As2O₅ (s) =2TiO₂ (s)+1/2As₄O₆ (g)+O₂ (g)
3 (2CuO·As₂O₅)(s) = 2 (3CuO·As₂O₅)(s)+1/2As₄O₆ (g) +O₂ (g)
2)In Ar atmosphere these arsenates start decomposing at about same temperature of 800°C
3) The equilibriumconstant K_p of the above reactions in inert gas flow can be estimated by measuring the equilibrium pressure of As₄O₆. The relation oflogK_p and 1/T obtained are as follows.
2TiO₂·As₂O₅: 750°-850°C
logK_p=-21.480×10³/T+ 16.6
2CuO·As₂O₅: 725°-825°C
logK_p=-21.270×10³/T+16.0

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The reductive dissolution of manganese dioxide in acidic aqueous solutions containing ferrous salts was studied from both thermodynamic and kinetic points of view. A rotating disc technique was employed in this study. This reaction is thought to be expressed as:
MnO₂+2Fe²⁺+4H⁺=Mn²⁺+2Fe³⁺+2H₂O
or,
MnO₂+2Fe²⁺+4H₂O= Mn²⁺+2Fe (OH) ₃+2H⁺.
It was, observed that the reaction rates were of 0.85th orderwith respects to ferrous ion concentration, while no distinct dependency was observed for acid concentration. The activation energies for the reductive dissolution reactions were 14.0 kJ/mol in H₂SO₄ solution and 19.3 kJ/mol in HCl solution. The overall reaction was thought to be controlled by a mass transfer of ferrous ions through the boundary layer between the acidic solution and the surface of the manganese dioxide.
Leaching experiments were carried out by applying this reaction to the dissolution for theparticulate samples of low grade manganese dioxide ore and manganiferrous nodules from deep ocean. High recoveries of manganous ions in the leach solution were achieved at room temperature after a very short retention time.

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