Solution Flow During Percolation Leaching of Ore Heaps

2013 ◽  
pp. 212-238
Keyword(s):  
2020 ◽  
Vol 64 (1) ◽  
pp. 23-28
Author(s):  
J. Hodač ◽  
Z. Fulín ◽  
P. Mareš ◽  
J. Veselá ◽  
O. Chocholatý

AbstractTo produce realistic test specimens with realistic flaws, it is necessary to develop appropriate procedure for corrosion flaw production. Tested specimens are made from steels commonly used in power plants, such as carbon steels, stainless steels and their dissimilar weldments. In this study, corrosion damage from NaCl water solution and NaCl water mist are compared. Specimens were tested with and without mechanical bending stress. The corrosion processes produced plane, pitting and galvanic corrosion. On dissimilar weldments galvanic corrosion was observed and resulted to the deepest corrosion damage. Deepest corrosion flaws were formed on welded samples. The corrosion rate was also affected by the solution flow in a contact with the specimens, which results in a corrosion-erosive wear. Produced flaws are suitable as natural crack initiators or as realistic corrosion flaws in test specimens.


2020 ◽  
Vol 71 (1) ◽  
pp. 1-12
Author(s):  
Salman H. Abbas ◽  
Younis M. Younis ◽  
Mohammed K. Hussain ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor ◽  
...  

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.


Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 306
Author(s):  
Kazuya Taira ◽  
Tomonori Waku ◽  
Yoshimichi Hagiwara

The control of ice growth inside channels of aqueous solution flows is important in numerous fields, including (a) cold-energy transportation plants and (b) the preservation of supercooled human organs for transplantation. A promising method for this control is to add a substance that influences ice growth in the flows. However, limited results have been reported on the effects of such additives. Using a microscope, we measured the growth of ice from one sidewall toward the opposite sidewall of a mini-channel, where aqueous solutions of sodium chloride and antifreeze protein flowed. Our aim was to considerably suppress ice growth by mixing the two solutes. Inclined interfaces, the overlapping of serrated interfaces, and interfaces with sharp and flat tips were observed in the cases of the protein-solution, salt-solution, and mixed-solution flows, respectively. In addition, it was found that the average interface velocity in the case of the mixed-solution flow was the lowest and decreased by 64% compared with that of pure water. This significant suppression of the ice-layer growth can be attributed to the synergistic effects of the ions and antifreeze protein on the diffusion of protein.


1990 ◽  
Vol 34 (2) ◽  
pp. 223-244 ◽  
Author(s):  
H. Müller‐Mohnssen ◽  
D. Weiss ◽  
A. Tippe

2016 ◽  
Vol 56 ◽  
pp. 218-226 ◽  
Author(s):  
Zhuo Zhang ◽  
Valeria Arrighi ◽  
Lydia Campbell ◽  
Julien Lonchamp ◽  
Stephen R. Euston

1981 ◽  
Vol 103 (4) ◽  
pp. 491-496 ◽  
Author(s):  
J. T. Kuo ◽  
L. S. G. Kovasznay

A novel flow configuration was explored for the study of the behavior of drag reducing polymers. A screw pump consisting of a smooth cylinder and a concentrically placed screw was used to create a strongly three-dimensional but essentially laminar flow. In the first phase of the study, the static pressure head developed by the screw pump was measured as a function of polymer concentration (polyox 10 to 100 ppm in water). A large increase of the developed head was observed that behaved in an analogous manner to drag reduction as far as concentration and straining of the polymer solution was concerned. In the second phase of the study, a new apparatus was constructed and the additional parameter of a superimposed through flow was included and the degree of failure of the superposition principle was established. Sensitivity of the phenomenon to chemicals like HCl, HNO3, and NaOH in the polymer solution was also studied. When the effect of these chemicals on the polymer solution flow behavior was presented in terms of the pH value of the polymer solution, it showed a similar trend to those observed in drag reduction.


Author(s):  
M. Shunmugasundaram ◽  
A. Praveenkumar ◽  
L. Ponraj Sankar ◽  
S. Sivasankar

Mechanical properties of materials are enhanced by different methods to increase the usage of the materials. In this research spray pyrolysis method is employed to increase the mechanical characteristics of three different materials. The tin oxide is chosen as coated material and aluminium, brass, mild steel are selected as substrate materials. The 500nm thin film is developed over the substrate materials by spray pyrolysis. The substrate temperature are chosen as 300? C for aluminium, 400? C for brass and mildsteel. Nozzle to substrate distance is 0.4 m, substrate temperature is 300? C for aluminium and 400? C for solution concentration as 0.2 mole and solution flow rate is 1ml/min are selected for constant deposition parameters. The hardness and tensile strength result clearly shows that strength is increased by adding the coating over the surface. The material is heated above crystallization temperature and SnO2 increases the tensile and hardness strength of the materials. The triangular metrological microscope is used to examine the microstructure of non coated and coated substrate materials. The microstructural analysis is showed that the uncoated surface of the substrate material is full of rough and pores. And displays that the tin oxide coated surface of the substrates after the initial deposition disclosed a surface with a agglomeration of tin oxide in homogeneous and uniform than the uncoated substrates.


Sign in / Sign up

Export Citation Format

Share Document