Sewage and sludge are a kind of organic fertilizer that is rich in organic matter,nitrogen and other microelements,and it also contains pathogeny microbes and parasitic ovum etc.

• 城市污泥是一种富含有机质、高氮、高磷及多种微量元素的有机肥,并含有病原微生物、寄生虫卵等。