Removal of Phosphate from Wastewater with Modified Dolomite
摘要
Limiting the influx of phosphorus compounds into water bodies is important for regulating anthropogenic eutrophication. Excessive influx of phosphorus leads to changes in their trophicity. Increased trophicity leads to "blooming" and a decrease in water quality. Modern methods of phosphate removal from industrial wastewater are considered, each with its advantages and disadvantages. The article shows that thermally modified dolomite (at a processing temperature of 800 C for 3 h) is a material that effectively removes phosphates. When used for the treatment of industrial wastewater, the maximum degree of extraction was 99% (with an initial phosphate content in water of 50 mg/dm3). The kinetics of phosphate removal and options for intensifying the treatment process were studied. It was established that air aeration of a suspension of modified dolomite in wastewater allows for achieving almost 100% degree of purification in 30 min. X-ray phase analysis established that due to chemical reactions during the interaction of phosphates with modified dolomite, calcium phosphate with a small amount of calcium hydrogen phosphate is formed. Based on these data, it can be stated that modified dolomite is a promising adsorbent for treating industrial wastewater. Optimization of the technical aspects of the proposed process in further research will allow its effective implementation in the production process with subsequent utilization of the spent sorbent as a soil former.