Changzhou Ouna Drying Equipment Co., Ltd. of alumina production line influence in alumina producing Bayer process stripping, and red mud settling performance and seed decomposition process, evaporation process and aluminium hydroxide roasting process factors and process optimization; sintering cement clinker burning, clinker leaching, sodium aluminate solution, the removal of silica and carbonate decomposition; Bayer and sintering process of alumina production by the new technology development and application; the sustainable development of alumina industry in China direction.