市政污泥与磷矿渣共堆肥制备营养覆土

为无害化处理市政污泥，结合矿山生态修复对营养基质的需求，采用翻堆式静态好氧堆肥工艺，以市政污泥、园林绿化废物和磷矿渣为主要原料，经过一次发酵，制备可用于矿山修复的营养覆土。实验中选用晋宁三浑水原矿和黄磷矿渣等2种磷矿渣。与以单一园林绿化废物为骨料的市政污泥传统堆肥方式相比，加入适量黄磷矿渣，能够促进堆体的一次发酵（50 ℃以上），高温启动时间由5 d缩短为3 d以内，高温持续时间在10 d左右；同时，能够促进营养覆土中腐殖质积累，将种子发芽指数提高到100%以上，并有效固化重金属，浸出液中高毒类金属As的浓度降至50 μg?L-1以下，处于安全水平。市政污泥、园林绿化废物与适量黄磷矿渣经过一次发酵制备的营养覆土可应用于矿山修复。

Nutrient overlying soil preparation by co-composting of municipal sewage sludge and phosphorous slag

To dispose municipal sewage sludge and meet the nutrition demand in the ecological remediation of the mining sites, the primary fermentation of turning static aerobic composting process was used in this investigation to prepare nutrient overlying soil in mine remediation, with municipal sewage sludge, landscaping waste and phosphate slag as the main raw materials. The phosphorous slag used in the experiment included ore from Jinning Sanhunshui and yellow phosphate slag. Compared with the conventional composting method of municipal sewage sludge with landscaping waste as single additive, the addition of the appropriate amount of yellow phosphate slag could promote primary fermentation temperature of the reactor (above 50 ℃). The start time of high temperature became shorter from 5 d to less than 3 d, and the high temperature duration kept for about 10 days. Meanwhile, the accumulation of humus in nutrient overlying soil accelerated, seed germination index increased to more than 100%, and heavy metals was solidified effectively. The concentrations of As, a highly toxic metal, in the leaching solution dropped to less than 50 μg?L-1, which was at a safe level. The nutrient soil derived from co-composting of municipal sewage sludge, landscaping waste and a appropriate addition amount of yellow phosphate slag has the potential to remediate the mining sites.