不同活性炭的改性及其吸附废水中氨氮的实验研究

Modification of Different Activated Carbons and its Adsorption of Ammonia Nitrogen in Wastewater

选用果壳、煤质、木质、椰壳(粉末)和椰壳(颗粒)活性炭,分别进行酸化、碱化和盐化改性,选出对于氨氮吸附效果最好的炭,进行最佳吸附条件(改性浓度、投加量、吸附时间)实验的研究,并分析不同pH值和不同初始氨氮浓度对氨氮去除效果的影响。研究结果表明:碱化颗粒态椰壳对于氨氮的吸附效果最好,NaOH最佳改性浓度为1 mol/L,最佳吸附时间为6 h。对于氨氮浓度为20 mg/L的废水,最佳投加量为5 g,吸附率可达到60%。pH对于氨氮吸附总体影响不大,但pH=6左右较好。废水低初始浓度条件下,活性炭对于氨氮吸附率随着氨氮浓度增大而减小。高浓度下,随氨氮浓度增大而增大。

Activated carbons such as shell,coal,wood,powder coconut shell and granule coconut shell were modified with acidification,alkalization and salinization respectively,and the best activated carbon of adsorption on ammonia nitrogen was selected.The adsorption of this carbon was studied under the conditions of different modified concentration,dosage,and adsorption time.And the effects of different pH values and different initial ammonia nitrogen concentrations on ammonia nitrogen removal were also analyzed.The study showed that alkalized granular coconut shell has the best effect on the adsorption of ammonia nitrogen.The optimal concentration of NaOH is 1 mol/L,and the optimal adsorption time is 6 hours.For wastewater with ammonia nitrogen concentration of 20 mg/L,the optimal dosage is 5 g,and the removal rate can reach 60%.The value of pH has little effect,but pH=6 is better.When the initial concentration of ammonia nitrogen in wastewater is low,the removal rate decreased with increasing ammonia nitrogen concentration.Otherwise it increased with increasing ammonia nitrogen concentration.