Zn/Al-LDH及其焙烧产物对污水处理厂尾水除磷的研究

Study on Phosphorus Removal from Tailwater for Wastewater Treatment Plant by Zn/Al-LDH and Its Calcined Products

课题组用尿素水解法合成锌铝层状双金属氢氧化物(Zn/Al-LDH),再在不同温度下(200°C、400°C、600°C和800°C)焙烧得到其焙烧材料。将上述材料放入萍乡市某污水处理厂尾水中进行磷吸附实验,发现200°C焙烧得到的Zn/Al-LDH-2材料除磷效果最佳,可将尾水中的总磷含量由原来的0.1705 mg/L降至0.0544 mg/L,总磷吸附量为0.2903 mg/g,去除率为68.1%。最后研究了Zn/Al-LDH和四种焙烧材料对污水处理厂的尾水进行3次总磷吸附/脱附实验,结果发现所有材料对每次的总磷吸附量并未减少,3次循环实验都可以实现磷的完全脱附。

Zinc-aluminum layered double hydroxide(hereinafter referred to as Zn/Al-LDH) is obtained by urea hydrolysis method, and then calcined at different temperatures(200°C, 400°C, 600°C and 800°C). The above materials are put into the tail water of a wastewater treatment plant in Pingxiang for phosphorus adsorption experiments, the results show that the Zn/Al-LDH calcined at 200°C have the best phosphorus removal effect,which can reduce the total phosphorus concentration from 0.1705 mg/g to 0.0544 mg/g at an adsorption capacity of 0.2903 mg/g with a removal rate of 68.1%. Then the total phosphorus adsorption and desorption experiments of Zn/Al-LDH and four kinds of calcined materials in the tail water of wastewater treatment plant are carried out three times. The results show that the total phosphorus adsorption capacity of all the materials do not decrease,and the complete phosphorus desorption could be achieved in three cycles.