Bauxite is a natural, very hard mineral and is primarily comprised of aluminum oxide compounds(alumina), silica,iron oxides and titanium dioxide. Approximately 70 percent of the world’s bauxite production is refined through the bayer chemical process into alumina. Bauxite is the ideal raw material for the manufacturing of alumina. Aside from the primary constituents of aluminum and silicon, bauxite is frequently coupled with many valuable elements such as gallium (Ga),titanium(Ti),scandium(Sc), and lithium(Li).The bauxite residue and circulating spent liquor in alumina production typically include significant amounts of valuable elements, making them a potential source of polymetallic. The recovery of these essential components can greatly increase alumina manufacturing process efficiency while reducing industrial liability and environmental impact. This study gives a critical analysis of existing technology used to recover valuable elements from bauxite residue and circulating spent liquor to provide insight into the broader usage of bauxite residue as a resource rather than a waste. A comparison of existing process features demonstrates that an integrated process for valuable elements recovery and waste emission reduction is advantageous.

Items	Al2O3	Fe2O3	B.D.
86	86% min	2% max	2.9-3.15
85	85% min	2% max	2.8-3.10
84	84% min	2% max	2.8-3.10
83	83% min	2% max	2.8-3.10
82	82% min	2% max	2.8-3.0
80	80% min	2% max	2.7-3.0
78	78% min	2% max	2.7-2.9
75	75% min	2% max	2.6-2.8
70	70% min	2% max	2.6-2.8
50	50% min	2% max	2.5-2.55

Itams	Al2O3	Fe2O3	B.D.	K2o+Na2o	CaO+MgO	TiO2
88	88% min	1.5% max	3.25 min	0.25% max	0.4% max	3.8% max
87	87% min	1.6% max	3.20 min	0.25% max	0.4% max	3.8% max
86	86% min	1.8% max	3.15 min	0.3% max	0.5% max	4 % max
85	85% min	2.0% max	3.10 min	0.3% max	0.5% max	4% max
83	83% min	2.0% max	3.05 min	0.3% max	0.5% max	4% max
80	80% min	2.0% max	3.0 min	0.3% max	0.5% max	4% max
78	75-78%	2.0% max	2.8-2.9	0.3% max	0.5% max	4% max

Itams	Al2O3	Fe2O3	B.D.	K2o+Na2o	CaO+MgO	TiO2
90	90% min	1.8% max	3.4 min	0.3% max	0.5% max	3.8% max
89	89% min	2.0% max	3.38 min	0.3% max	0.5% max	4% max
88	88% min	2.0% max	3.35 min	0.3% max	0.5% max	4% max
87	87% min	2.0% max	3.30 min	0.3% max	0.5% max	4% max
86	86% min	2.0% max	3.25 min	0.3% max	0.5% max	4% max
85	85% min	2.0% max	3.20 min	0.3% max	0.5% max	4% max
83	83% min	2.0% max	3.15 min	0.3% max	0.5% max	4% max

Based on the fact that bauxite clinker has minor thermal conductivity and better skid resistance and wear-resisting property,it can be used in HFST(high friction surface treatment) or the abrasion layer of asphalt mixture to replace or partly replace the existing aggregate. Bauxite clinker is classified into mainly six types according to different chemical composition contents. The selection of bauxite clinker as aggregate is not only for the economic value,but also for improving the adhesion between aggregate and asphalt,which has a certain blindness.This study evaluated the characteristics of different types of bauxite clinker.The adhesion of different types of bauxite clinker with asphalt was evaluated by means of agitating hydrostatic adsorption method and surface free energy theory.The effect of characteristic parameters of bauxite clinker on adhesion was evaluated by grey correlation entropy analysis.