Abstract An estimate has been made of the feasibility a metallurgical purification process, NEDO (New Energy and Industrial Technology Development Organization) melt‐purification for manufacturing solar‐grade silicon from metallurgical‐grade silicon. Equipment developed to pilot plant scale. The system comprises an electron‐beam furnace phosphorus removal plasma boron removal. Each mold directional solidification remove metallic impurities. concentration each impurity in ingot purified...

The particle dispersion behavior was compared for ultrasonic irradiation and mechanical stirring. experiment calculation were carried out with polymethylmethacrylate (PMMA) particles. rate of the agglomerated particles increased decreasing frequency increasing electric power, whereas it rotation speed temporal change in proceeded stably after passage a long time. suggested to occur by erosion from surface cluster one due bulk cavitation as well division into smaller because inner cavitation,...

An equation for the floating velocity of cluster-shaped alumina inclusions which considers changes in average density was derived by quantifying size and clusters using fractal theory. The results obtained showed that dependency on cluster diameter is smaller than conventional equations, assume have a uniform density. In particular, 100 μm over considerably velocity. A model coalescence also constructed, behavior molten steel tundish an actual continuous casting machine analyzed considering...

Oxidation and removal of boron from molten silicon by a steam-added plasma melting method was investigated as an important part sequential metallurgical process for producing high-purity solar grade (SOG-Si) commercially available (MG-Si). Experiments were carried out with the mass per charge varied in range 0.6 to 300 kg, corresponding laboratory scale industrial scale. Boron removed [B] < 0.1 ppm, which is permissible content SOG-Si. The deboronization rate proportional steam content,...

The evaporation behavior of phosphorus in molten silicon during electron beam irradiation was investigated with the aim producing solar grade (SOG-Si) from metallurgical (MG-Si) by a sequential process. Batch experiments showed that rate increased proportion to power and content. removal controlled free surface. Electron makes it possible secure higher temperature at liquid surface, which results more efficient dephosphorization. A continuous flow experiment indicated concentration outlet...

Chlorine removal from polyvinyl chloride (PVC) with the addition of catalysts, such as solid acid and adsorbents, alkali metal oxide, including a multiple one, was described using superheated steam nitrogen pyrolysis media in this research. The effect dechlorination temperature indicated that treatment an important factor to control carbonization ratio PVC. single TiO2, MgO, CoO, showed better ability compared β-zeolite NaOH. CoO had higher than TiO2 MgO. metal-oxide-supported adsorbent...

An industrial-scale pyrometallurgical method of removing metallic impurities from metallurgical grade silicon (MG-Si) was developed as an element technology in a sequential purification process for manufacturing high-purity solar (SOG-Si) by segregation during solidification. Metallic were removed MG-Si using electron beam heating equipment. Molten supplied continuously at constant mass to water-cooled copper mold and allowed solidify gradually unidirectional manner the bottom upward. This...

Synopsis:Water model experiments have been conducted to clarify mixing rates of molten steel and mass transfer between slag metal in Q-BOP with a particular emphasis on the comparison those LD.Complete time determined by tracer dispersion technique is, respectively, 23 26 sec for Q-BOP, 100 200 LD. This indicates that stirring intensity is remarkably larger than LD when compared same flow rate gas. A simple relationship obtained time, τ (sec), gas, Q(Nl/min) number tuyeres, N τ=41.80...

Theoretical and experimental studies were carried out to quantitatively understand the effect of fluid flow on decarburization reaction rate in an RH degasser. Hydrodynamic calculations ladle proved reasonable by a cold model experiment. The conjunction with hydrodynamic made it clear that obtained from this was faster than for perfectly mixed flow, slower plug when same parameters used calculations. enabled us predict concentration distribution carbon during treatment. maximum content,...

The rate of shape control alumina inclusions with calcium in line pipe steel for sour service is determined by a 30 kg high frequency induction furnace. proceeds the increase time after addition. degree increased stirring energy supplied and decrease from aluminum addition to Applying unreacted core model experimental results, determining step believed be diffusion calcium-aluminate product layer.

Water model experiment has been carried out to investigate motion of bath in bottom blown converter with tuyeres set two rows.Visual observation indicated the occurrence types wave motions (A- and B-type). A type is similar that generated a U-shaped tube. B resembles separated bubble regions interfere laterally repeat collision repulsion alternately.The generation varied by gas flow rate, depth tuyere configuration. On keeping rate at which either generated, criterion for characterized H/D...

Experimental and theoretical studies were carried out to clarify shape control of alumina inclusions during calcium double treatment in a line pipe steel for sour service. Calcium (Ca) addition method experimented by 280 t-scale commercial plant.In this method, Ca powder was firstly injected flux injection process (FI), secondly added MnS CaS tundish continuous casting machine after eliminating the first step RH degasser.The degree increased compared with that conventional FI or addition,...

Cold model experiment on ion-exchange reaction between pearlite particles and HCl aq. was carried out in order to understand the effect of dispersion operating factors solid/liquid mass transfer rate a mechanically-stirred vessel. Inner diameter vessel varied conjunction with both bath depth as 400 (base) 300 mm. Rotation speed volume ratio liquid were changed 0–240 rpm, 0.02–0.24 (–), respectively.When rotating increased, increased moderately regions I III, whereas it region II. When...

In order to find out effect of operating factors on mixing pattern which affects liquid/liquid mass transfer rate drastically, cold model experiment was carried with liquid paraffin or tetradecane as a dispersed phase and ion-exchanged water continuous in mechanically stirred vessel. There exist three types mechanical agitation. I: region where each separates has no dispersion, II: vortex (liquid/liquid interface) arrives at impeller position its dispersion begins into phase, III: gas/liquid...

A pyrometallurgical process for manufacturing solar grade silicon (SOG-Si) from metallurgical (MG-Si) was developed. Metallic elements in MG-Si such as iron, titanium and aluminum, which show low partition coefficients, were removed by directional solidification practice. Phosphorus removal carried out evaporation high vapor pressure, boron changed to oxide effectively water addition, because coefficients of phosphorus are close unity.To satisfy the impurity specification SOG-Si, each...

In order to maximize the recovery of silicon wafer in waste crystalline solar cells, chemical treatment has been carried out by using mixed solution hydrofluoric acid (HF) and nitric (HNO3). The effect HF HNO3 concentrations on etching rates several components such as silver (Ag), aluminum (Al), anti-reflection film made nitride (AR) (Si) cells clear. Ag, Al Si are held almost constant with time become larger increasing concentration temperature. All Al, AR have peaked at mole fraction about...

Abstract To compare oil‐in‐water emulsification behaviors between ultrasonic irradiation and impeller stirring, experiments calculation by mathematical models were performed. For irradiation, the peak diameter of dispersed oil droplets decreased with an increase in input power reductions frequency, ratio volume, interfacial tension. mechanical it declined higher rotation speed. The results calculated approximately agreed experiments. Ultrasonic was better than stirring for producing a fine...

In this study, a calculation procedure of gas/liquid mass transfer capacity coefficients based on liquid/liquid ones was developed and cold model studies benzoic acid between water liquid paraffin, oxygen among water, paraffin air carried out under various top/bottom blowing rates volume ratios. The rate increased with the increase in top rate, but increasing larger vessel diameter to lower than that smaller one. both bottom rates, difference became reduced rate. minimize sum gas flow almost...