Preparation and regeneration ability test of a new type of phosphorus removal filler

Abstract

Zeolite,fly ash and coal gasification slag were used as raw materials to prepare a new type of phosphorus removal filler with low cost and high efficiency through artificial improvement, and its adsorption performance and regeneration ability were explored. The changes in the microstructure, elemental composition, and crystal structure of the filler phosphorus before and after adsorption was analyzed. The research results indicated that the main components of the filler were O, Si, Ca, Al, Fe, Mg, of which Ca had the highest mass fraction. The surface of the fillers became smooth and flat after adsorption, EDS and XRD analysis indicated that Ca played an important role in the adsorption process. Under the conditions of a phosphorus concentration of 50 mg/L and an adsorbent of 14 g/L, the new phosphorus removal filler achieved a phosphorus removal rate of 80%, and its adsorption performance was significantly improved compared with the raw materials. Under the environmental conditions of pH=1 and pH=13, the release rates of the fillers were 142.39% and 83.26% respectively. The desorption effect under acidic conditions was significantly better than that under alkaline conditions, indicating that strong acids/bases were beneficial for the release of phosphorus from the fillers. The experimental study on regeneration capacity showed that after four regenerations,the removal rate of phosphorus by the acidic regeneration filler was significantly lower than that by the alkaline regeneration filler. In practical applications of alkaline regeneration 1-2 times, the removal rate of phosphorus by the filler was over 60%, which had a high possibility of regeneration and reuse.

Keywords

• coal gasification slag
• zeolite
• fly ash
• adsorption
• regenerative capacity
• phosphorus removal