Efficient Sulfide Recovery Through Fluidized Bed Homogeneous Crystallization Technology for Nickel Sulfide Production from Sulfide-Contained Wastewater

Abstract

Fluidized bed homogeneous crystallization (FBHC) is used to recover dissolved sulfur using nickel as a precipitant from aqueous solution as granulated nickel sulfide particles. The optimum operating parameters, including, pH, precipitant dosage of [Ni2+]0/[S2-]0 and cross–sectional surface sulfide loading (LS, kg/m2.hr), are determined. Inorganic (NO3–, CO32–, PO43–, F−and Cl−) and organic (acetic acid, oxalic acid, EDTA, and Citric acid) interference ions are used to determine the effect of impurities in the granules of nickel sulfide. Under optimum operating conditions of pH = 9.8 [Ni2+]0 / [S2-]0 = 0.75, LS = 1.5 kg/(m2h) the highest total sulfur removal (TR) and crystallization ratio (CR) is 96.8% and 95.3%, respectively. FBHC is an alternative method to treat a solution containing sulfur that produces granulated nickel sulfide pellets to prevent the production of excessive sludge, which is commonly produced by conventional chemical precipitation methods.

Keywords: Nickel sulfide, Sulfide removal, Fluidized-bed homogeneous crystallization, Cross-sectional surface loading