污泥焚烧工程中的磷形态分布与磷迁移研究

Phosphorus Forms Distribution and Migration in Sludge Incineration Project

以竹园污泥焚烧工程为依托,采用SMT方法研究磷在干污泥、炉渣和飞灰中的含量及赋存形态。结果表明,焚烧过程使炉渣及飞灰中的总磷(TP)含量比干污泥提高了2~3倍,还使其中的无机磷(IP)含量大幅提升至TP总量的99%以上,在实现磷富集的同时有效提升了磷的生物可利用性。分析焚烧过程对磷灰石无机磷(AP)和非磷灰石无机磷(NAIP)的影响,发现镁离子与钙离子会与污泥中的NAIP发生反应,取代铝离子从而生成钙镁结合形式的AP;与炉渣相比,飞灰在布袋处受CaO添加的影响,此种转化趋势更为明显,AP已经超过NAIP成为优势形态,占IP总量的78.4%。焚烧是上海地区处理污泥的主要方式,该研究结果从营养物回收角度为污泥焚烧飞灰的资源化利用提供了新思路。

Based on Zhuyuan sludge incineration project,contents and forms of phosphorus in dry sludge,slag and fly ash were explored by using SMT method.The total phosphorus(TP)contents in slag and fly ash were 2 to 3 times higher than that in dry sludge,and the inorganic phosphorus(IP)contents in slag and fly ash were increased to more than 99%of the total TP.Therefore,the phosphorus bioavailability was effectively improved while phosphorus enrichment was realized.The effects of incineration process on apatite inorganic phosphorus(AP)and non-apatite inorganic phosphorus(NAIP)were analyzed.It was found that magnesium and calcium ions reacted with NAIP in sludge,replacing aluminum ion to form calcium-magnesium binding AP.Compared with slag,this transformation trend in fly ash was more obvious because of CaO addition in bags,and the AP surpassed NAIP to become the dominant form,accounting for 78.4%of the total IP.As incineration is the main way of sludge treatment in Shanghai,the above conclusions provide a new idea for resource utilization of fly ash created in sludge incineration from the perspective of nutrient recovery.