Study on the removal of high contents of ammonium from piggery wastewater by clinoptilolite and the corresponding mechanisms

Abstract

AbstractIn this study, a clinoptilolite was applied to remove ammonium from piggery wastewater. The performance of ammonium removal and the correspondingly mechanisms were discussed. Under the optimal conditions of clinoptilolite dosage of 12 g/L, solution pH value of 8.3, shaking speed of 280 rpm and contact time of 55 min obtained by using response surface methodology (RSM), 19.7 mg of ammonium can be adsorbed onto 1 g of clinoptilolite, which was declined when metal cations were presented in the piggery wastewater. The ammonium adsorption process by the clinoptilolite can be well fitted by Langmuir isotherm with a spontaneous nature and pseudo–second–order kinetics model. Furthermore, column study showed that to some extent, the increased flow rate was beneficial to the removal of ammonium, and the ammonium adsorption capacity of clinoptilolite in column study was much higher than those in batch study.