Flotator model of less sensitive to fuel quality

Flotator model of less sensitive to fuel quality

The intrusion of anionic collector in between adjacent surface alkyl ammonium ions decreases electrostatic head-head repulsion, thereby increasing the diamine adsorption by increasing the hydrophobic tail-tail bonds. The discrepancy in the flotation and adsorption results at pH 2 is attributed to the coarse and fine size particles employed in these studies, respectively. The comparable adsorption on fine particles of albite and quartz at pH 2 is explained by the interaction of ammonium ions on silanol groups by hydrogen bonding besides electrostatic interactions.
In contrast, the three model Mega range, with bucket capacities ranging from 2.5 to 4.5m3, are powered by Doosan Tier 1 (the DL250A) and Tier 2 diesel engines (the larger DL300A and DL420A models), which are less sensitive to fuel quality than Tier 3 engines, whilst still offering reduced fuel consumption and emissions.
Using pure albite and quartz minerals, the separation of albite from quartz using mixed cationic/anionic reagent schemes is assessed through Hallimond flotation, zeta potential and diffuse reflectance FTIR studies. The reagent schemes are tested in bench-scale flotation for the separation of albite from Greek Stefania feldspar ore. The single mineral flotation tests showed the feasibility of selective albite flotation from quartz at around pH 2 using a mixture of cationic diamine and anionic sulfonate collectors or a combined cationic-anionic collector of diamine-dioleate.
A key focus on the Mega range has also been ease of serviceability - the radiator grille on the DL250A opens wider for better access, while the swing-out fan on the DL300A and DL420A simplifies maintenance, for instance.
In contrast to the selective flotation response of albite at pH 2, where albite is slightly negatively charged and quartz possess zero charge, the zeta potential and FTIR studies elucidate similar adsorption behavior of mixed collectors on both of the minerals. The infrared spectra not only showed the co-adsorption of anionic sulfonate or oleate with diamine on the surface but also showed that the diamine adsorption increases with the presence of anionic collector.
This two-tiered approach is also reflected in the latest launches from both Doosan as well as JCB. Doosan's new 22. The bench-scale results indeed showed that selective albite flotation takes place only after desliming the feed material. An albite concentrate exceeding 10% (by weight) Na2O is produced from a material containing about 6.5% (by weight) Na2O, where an albite product of more than 9% (by weight) Na2O is considered to be valuable.