改性粉煤灰对燃煤电厂脱硫废水中氯离子的吸附性能

Adsorbility of modified fly ash to chloride ions in desulfurization wastewater from coal-fired power plant

为了将"以废治废"的理念融入实际工业应用中,开展对燃煤电厂固体废弃物粉煤灰改性后在不同条件下进行脱硫废水的吸附实验研究。结果表明,改性粉煤灰的最佳投加量为25 g/L,此时对废水中Cl^(-)的去除率最大,为56%;在45℃和pH为5的条件下,粉煤灰对Cl^(-)的吸附量最大,在反应约280 min时达到吸附平衡。该吸附过程为吸热反应,且符合Langmuir等温吸附模型。改性粉煤灰吸附前后物相组成、官能团的明显变化进一步说明改性后粉煤灰的吸附性能增强,吸附主要以物理吸附为主,同时伴有化学吸附过程。

In order to integrate the concept of"using waste to treat waste"into practical industrial applications,the adsorption of desulfurization wastewater by adsorption with fly ash produced in a coal-fired power plant after modification was studied experimentally under different conditions.The results showed that the optimal dosage of modified fly ash was 25 g/L,where the removal rate of Cl-was as maximum as 56%.The adsorption amount of Cl-was maximum at temperature45℃and pH 5,and the adsorption equilibrium was established after reaction for 280 min under the given conditions.The reaction was endothermic and in line with Langmuir isotherm adsorption model.The phase composition and functional groups of the modified fly ash were changed significantly after adsorption,indicating that the adsorption performance of fly ash was improved after modification.The adsorption was mainly a physical process accompanied with chemical reaction.