城市生活垃圾焚烧炉渣对可溶性磷的去除研究

Study on Removal of Soluble Phosphorus by Municipal Solid Waste Incineration Bottom Ash

城市生活垃圾焚烧炉渣(MSWA)富含Ca、Fe、Al等金属物质且具有一定的比表面积(7.24 m^2/g),对溶解性的磷具有良好的化学沉淀及吸附去除作用。实验研究表明,MSWA对磷的去除随水溶液pH值增加先呈递增而后有所下降,对5 mg/L的含磷溶液,当pH=8.01时,MSWA对磷的去除率可达93.95%,且溶液中SO 4^2-、NO3^-及Cl^-阴离子并未明显的影响MSWA对磷的去除。通过对MSWA去除水体中磷的过程研究发现,MSWA对磷的去除符合Langmuir曲线( R^2=0.994)、并遵循二级动力学方程(R^2=0.971),理论饱和去除量可达6.623mg/g。

Municipal solid waste incineration bottom ash (for short MSWA) is not only rich in calcium, ferrum and aluminum ions, but also has a relative large specific surface area of 7.24 m^2/g, which has a good chemical precipitation and adsorption and removal effect on dissolved phosphorus. It has been shown that, for a solution with phosphate of 5 mg/L, the phosphate removal by MSWA increases firstly as pH value increasing and then decreases, the optimal removal for phosphate can reach 93.95% as pH being of 8.01. Meanwhile, the coexisting anions, SO4^2-,NO3^- and Cl^-, have not any effects on phosphate removal even as their concentration increase high to 400 mg/L. By studying the phosphorus removal process of MSWA in water, it is found that the phosphorus removal by MSWA conforms to the Langmuir curve ( R^2=0.994) and follows the second-order kinetic equation ( R^2=0.971), and the theoretical saturated removal amount can reach 6.623 mg/g.