Silicon Carbide Recovery from Cutting Fluid Waste: Evolution of Recycling Performance for Valorization with Higher Added Value

Silicon ◽  
2021 ◽  
Author(s):  
M. Hecini ◽  
S. Beddek ◽  
M. Tablaoui ◽  
Y. Ayoucha ◽  
B. Palahouane ◽  
...  
2021 ◽  
Vol 123 ◽  
pp. 105512
Author(s):  
Chunyan Yao ◽  
Dongdong Chen ◽  
Kaixiang Xu ◽  
Zhongli Zheng ◽  
Qiangsheng Wang ◽  
...  

2015 ◽  
Vol 656-657 ◽  
pp. 28-32 ◽  
Author(s):  
Sheng Fu Yang ◽  
Chang Sing Hwang ◽  
Zong Yang Jhuang Shie ◽  
Chun Huang Tsai ◽  
Chun Liang Chang ◽  
...  

Silicon carbide (SiC) is widely employed as an abrasive material in aqueous media for sawing silicon ingot into individual wafers in photovoltaic industry. After a series of cutting, grinding and polishing operation, a mixture of substances (Cutting fluid, SiC, Si and small amount of magnetic metal) is produced as a form of slurry. The used SiC can be preferably recovered and reused for another application, rather than disposed of as waste. In this study, a pilot scale system (25 kg/h) is developed to extract SiC from photovoltaic industry abrasive slurry. The recovery system is composed of physical and chemical separation processes to remove silicon particles and magnetic materials which are dispersed in the slurry. X-ray diffraction analysis showed that purified powder is in the 6H-SiC structure and powder consists only of silicon carbide and has no residual silicon. It might be applied again in silicon ingot cutting or for other purposes which require this kind of ceramic material.


2021 ◽  
Vol 254 ◽  
pp. 117556
Author(s):  
Mouna Hecini ◽  
Meftah Tablaoui ◽  
Salaheddine Aoudj ◽  
Baya Palahouane ◽  
Ouahiba Bouchelaghem ◽  
...  

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1116 ◽  
Author(s):  
Jhao-Yi Lin ◽  
Rome-Ming Wu

In this study, through simulation and experimental verification, we proposed a novel hydrocyclone in which a tubular ceramic membrane passed through the overflow outlet to the underflow outlet. The centers of overflow and underflow outlets were tubular membranes equipped with an exit of outside-in filtration, and the overflow the underflow outlets were shaped into annular (donut shape) exits. Thus, this novel hydrocyclone has three outlets, namely the overflow dilute liquid, the underflow concentrated liquid, and clear filtrate. This system enabled higher dilution of hydrocyclone overflow concentration than that in the traditional system. Furthermore, underflow was more concentrated, and we obtained a clear filtrate. Therefore, this device can simultaneously perform classification and filtration, which is valuable for special liquid recycling. For instance, in wafer cutting fluid recovery in solar energy processes, the fluid with more silicon can function as the overflow, the fluid with more silicon carbide can function as the underflow, and the polyethylene glycol (PEG) organic solvent can function as the clear filtrate.


Author(s):  
R. J. Lauf

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.


Author(s):  
K. B. Alexander ◽  
P. F. Becher

The presence of interfacial films at the whisker-matrix interface can significantly influence the fracture toughness of ceramic composites. The film may alter the interface debonding process though changes in either the interfacial fracture energy or the residual stress at the interface. In addition, the films may affect the whisker pullout process through the frictional sliding coefficients or the extent of mechanical interlocking of the interface due to the whisker surface topography.Composites containing ACMC silicon carbide whiskers (SiCw) which had been coated with 5-10 nm of carbon and Tokai whiskers coated with 2 nm of carbon have been examined. High resolution electron microscopy (HREM) images of the interface were obtained with a JEOL 4000EX electron microscope. The whisker geometry used for HREM imaging is described in Reference 2. High spatial resolution (< 2-nm-diameter probe) parallel-collection electron energy loss spectroscopy (PEELS) measurements were obtained with a Philips EM400T/FEG microscope equipped with a Gatan Model 666 spectrometer.


Author(s):  
L. A. Giannuzzi ◽  
C. A. Lewinsohn ◽  
C. E. Bakis ◽  
R. E. Tressler

The SCS-6 SiC fiber is a 142 μm diameter fiber consisting of four distinct regions of βSiC. These SiC regions vary in excess carbon content ranging from 10 a/o down to 5 a/o in the SiC1 through SiC3 region. The SiC4 region is stoichiometric. The SiC sub-grains in all regions grow radially outward from the carbon core of the fiber during the chemical vapor deposition processing of these fibers. In general, the sub-grain width changes from 50nm to 250nm while maintaining an aspect ratio of ~10:1 from the SiC1 through the SiC4 regions. In addition, the SiC shows a <110> texture, i.e., the {111} planes lie ±15° along the fiber axes. Previous has shown that the SCS-6 fiber (as well as the SCS-9 and the developmental SCS-50 μm fiber) undergoes primary creep (i.e., the creep rate constantly decreases as a function of time) throughout the lifetime of the creep test.


Author(s):  
B. Lencova ◽  
G. Wisselink

Recent progress in computer technology enables the calculation of lens fields and focal properties on commonly available computers such as IBM ATs. If we add to this the use of graphics, we greatly increase the applicability of design programs for electron lenses. Most programs for field computation are based on the finite element method (FEM). They are written in Fortran 77, so that they are easily transferred from PCs to larger machines.The design process has recently been made significantly more user friendly by adding input programs written in Turbo Pascal, which allows a flexible implementation of computer graphics. The input programs have not only menu driven input and modification of numerical data, but also graphics editing of the data. The input programs create files which are subsequently read by the Fortran programs. From the main menu of our magnetic lens design program, further options are chosen by using function keys or numbers. Some options (lens initialization and setting, fine mesh, current densities, etc.) open other menus where computation parameters can be set or numerical data can be entered with the help of a simple line editor. The "draw lens" option enables graphical editing of the mesh - see fig. I. The geometry of the electron lens is specified in terms of coordinates and indices of a coarse quadrilateral mesh. In this mesh, the fine mesh with smoothly changing step size is calculated by an automeshing procedure. The options shown in fig. 1 allow modification of the number of coarse mesh lines, change of coordinates of mesh points or lines, and specification of lens parts. Interactive and graphical modification of the fine mesh can be called from the fine mesh menu. Finally, the lens computation can be called. Our FEM program allows up to 8000 mesh points on an AT computer. Another menu allows the display of computed results stored in output files and graphical display of axial flux density, flux density in magnetic parts, and the flux lines in magnetic lenses - see fig. 2. A series of several lens excitations with user specified or default magnetization curves can be calculated and displayed in one session.


2015 ◽  
Vol 25 (1) ◽  
pp. 50-60
Author(s):  
Anu Subramanian

ASHA's focus on evidence-based practice (EBP) includes the family/stakeholder perspective as an important tenet in clinical decision making. The common factors model for treatment effectiveness postulates that clinician-client alliance positively impacts therapeutic outcomes and may be the most important factor for success. One strategy to improve alliance between a client and clinician is the use of outcome questionnaires. In the current study, eight parents of toddlers who attended therapy sessions at a university clinic responded to a session outcome questionnaire that included both rating scale and descriptive questions. Six graduate students completed a survey that included a question about the utility of the questionnaire. Results indicated that the descriptive questions added value and information compared to using only the rating scale. The students were varied in their responses regarding the effectiveness of the questionnaire to increase their comfort with parents. Information gathered from the questionnaire allowed for specific feedback to graduate students to change behaviors and created opportunities for general discussions regarding effective therapy techniques. In addition, the responses generated conversations between the client and clinician focused on clients' concerns. Involving the stakeholder in identifying both effective and ineffective aspects of therapy has advantages for clinical practice and education.


Sign in / Sign up

Export Citation Format

Share Document