添加剂对堆肥降解多环芳烃的影响

Effect of additives on degradation of polycyclic aromatic hydrocarbons(PAHs) in composting

为了研究多环芳烃(PAHs)污染土壤堆肥修复的加速机制,在人工控温的堆肥装置中以芘、菲和芴为研究对象,采用室内模拟实验的方式研究了添加硫酸钙、过磷酸钙、草炭、竹炭、十二烷基硫酸钠(K12)和十二烷基苯磺酸钠(SD-BS)等对锯末高温堆肥降解污染土壤PAHs的影响。研究结果表明,生物堆肥可以有效的去除土壤中PAHs,堆肥7周后所有处理下芘、菲和芴的降解率基本达到80%以上。不同添加剂处理下芘、菲和芴降解率不同,尤其是添加草炭和竹炭处理中芴和菲在第4周的时候就取得90%以上的降解率,芘在第6周也取得80%以上的降解率,而且氮素的损失率也分别下降了42.6%和36.09%,比其他处理的PAHs降解率和保氮效果都要好。分析其原因,一方面可能是添加不同添加剂对堆肥过程中pH值、有机质(SOM)、总氮(TN)和过氧化氢酶(CAT)都有一定的影响,提高了土壤微生物的活性;另一方面可能是由于草炭和竹炭对氨有良好的吸附性,具有良好的保氮效果,同时也能改善了微生物和目标化合物的接触方式,从而提高了PAHs的降解率。

The degradation of pyrene （ Pyr）, phenanthrene （Phe） and fluorene （Flu） was investigated in the aerobic compost devices added with CaSQ, Ca（H2PO4）2, peat, bamboo charcoal, sodium dodecyl sulfate （K12） and dodecyl benzenesulfonic acid（SDBS）. It was suggested that biological compost could effectively de-grade PAHs and the degradation rates of Pyr, Phe and Flu were all above 80% after 7 weeks incubation. With the peat and bamboo charcoal added the degradation of Flu and Phe increased to more than 90% after 4 weeks incubation and the nitrogen losses was reduced compared with other treatments. The reasons of PAHs degradation increased by peat and bamboo charcoal added maybe lie in the facts that the nitrogen loss was reduced and the microbial activities were improved.