%0 Journal Article
%T Ash Depression in Fine Coal Flotation Using a Novel Polymer Aid
%A Ontlametse Molatlhegi
%A Lana Alagha
%J International Journal of Clean Coal and Energy
%P 65-85
%@ 2168-1538
%D 2016
%I Scientific Research Publishing
%R 10.4236/ijcce.2016.54006
%X The current study investigated the effects of novel hybrid polyacrylamide polymers as ash (slime) depressants in fine coal flotation to enhance combustible recovery and ash rejection. Coal samples at P<sub>80</sub> of approximately 45 um with ~25% ash content  were floated in the presence of in-house synthesized hybrid aluminum hydroxide polyacrylamide polymers (Al(OH)<sub>3</sub>-PAM, or Al-PAM). All flotation experiments were carried out in a 5-L Denver flotation cell. Various influencing factors were examined to optimize the flotation process in the presence of the Al-PAM polymers, including the Al-PAM dosage, Al-PAM conditioning time, impeller rotation speed and pulp pH. Comparative and synergistic studies were also performed using organic polyacrylamide polymers (PAMs), commercial dispersants and Al-PAM/dispersant system. Results showed a significant improvement in both combustible recovery and ash rejection at an Al-PAM dosage of 0.25 mg/L. The maximum combustible recovery obtained, at natural pH, with Al-PAM and Al-PAM/dispersant system was determined to be 70% and 66% at ash content of 7.74% and 7.4%, respectively. Zeta potential values of both the raw coal and concentrate products showed a large shift toward more positive values (from бе50 mV to бе13 mV), indicating a significant decrease in ash-forming minerals (slimes) when Al-PAM polymers were applied.
%K Fine Coal Flotation
%K Novel Organic/Inorganic (Hybrid) Polyacrylamide
%K Zeta  Potential
%K Slime Coating
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=72391