酸渣制备无水硫酸钠

采用炼油厂酸渣经水稀释后,添加含钠化合物进行中和反应,制备无水Na_2SO_4.最佳工艺条件为:将酸渣用水稀释20倍,按n(Na_2CO_3):n(SO_4~(2-))=1.10或n(NaOH):n(SO_4~(2-))=1.20的比例加入Na_2CO_3,溶液或NaOH溶液,油水分离去除油相后蒸发、干燥,在650℃下灼烧后溶解、过滤、蒸发、结晶,得到Na_2SO_4产品.NaCO_3法可将酸渣中约78%的SO_4~(2-)转化到产品Na_2SO_4中;NaOH法可将酸渣中约66%的SO_4~(2-)转化到产品Na_2SO_4中.制备的无水Na_2SO_4产品均达到GB/T6009-2003<工业无水硫酸钠>二类标准.

Preparation of Anhydrous Sodium Sulfate from Acid Sludge

Anhydrous Na_2SO_4 was prepared by neutralization reaction using the water-diluted acid sludge from an oil refinery and sodium-containing compounds. The optimum processes are as follows; diluting the acid sludge with 20 folds of water, adding Na_2CO_3 or NaOH solution according n(Na_2CO_3) : n(SO_4~(2-)) = 1.10 or n( NaOH) : n( SO_4~(2-)) = 1. 20, vaporizing and drying after removing oil-phase by oil-water separation, igniting the remains at 650 ℃ followed by dissolution, filtration, evaporation and crystallization, then the product Na_2SO_4 is obtained. 78% of SO_4~(2-) in the acid sludge can be transferred into the Na_2SO_4 product by Na_2CO_3 process, and 66% by NaOH process. The quality of the product can meet the second grade of national standard GB/T6009 -2003.