Kleemann Rosanna, Chenoweth Jonathan, Clift Roland, Morse Stephen, Pearce Pete, Saroj Devendra
Centre for Environment and Sustainability, University of Surrey, Guildford GU2 7XH, UK; Innovation Centre, Thames Water Utilities Ltd., Island Road, Reading RG2 0RP, UK.
Centre for Environment and Sustainability, University of Surrey, Guildford GU2 7XH, UK.
Waste Manag. 2017 Feb;60:201-210. doi: 10.1016/j.wasman.2016.10.055. Epub 2016 Dec 12.
This research compares and contrasts the physical and chemical characteristics of incinerator sewage sludge ash (ISSA) and pyrolysis sewage sludge char (PSSC) for the purposes of recovering phosphorus as a P-rich fertiliser. Interest in P recovery from PSSC is likely to increase as pyrolysis is becoming viewed as a more economical method of sewage sludge thermal treatment compared to incineration. The P contents of ISSA and PSSC are 7.2-7.5% and 5.6%, respectively. Relative to the sludge, P concentrations are increased about 8-fold in ISSA, compared to roughly 3-fold in PSSC. Both PSSC and ISSA contain whitlockite, an unusual form of calcium phosphate, with PSSC containing more whitlockite than ISSA. Acid leaching experiments indicate that a liquid/solid ratio of 10 with 30min contact time is optimal to release PO-P into leachate for both ISSA and PSSC. The proportion of P extracted from PSSC is higher due to its higher whitlockite content. Heavy metals are less soluble from PSSC because they are more strongly incorporated in the particles. The results suggest there is potential for the development of a process to recover P from PSSC.
本研究对焚烧炉污水污泥灰（ISSA）和热解污水污泥炭（PSSC）的物理和化学特性进行了比较和对比，目的是将磷回收为富含磷的肥料。随着热解与焚烧相比被视为一种更经济的污水污泥热处理方法，从PSSC中回收磷的关注度可能会增加。ISSA和PSSC的磷含量分别为7.2 - 7.5%和5.6%。相对于污泥，ISSA中的磷浓度增加了约8倍，而PSSC中约为3倍。PSSC和ISSA都含有白磷钙矿，这是一种不常见的磷酸钙形式，PSSC中的白磷钙矿含量比ISSA更多。酸浸实验表明，对于ISSA和PSSC，液固比为10且接触时间为30分钟是将PO-P释放到渗滤液中的最佳条件。由于PSSC中白磷钙矿含量较高，从PSSC中提取的磷比例更高。重金属在PSSC中的溶解度较低，因为它们更强烈地结合在颗粒中。结果表明，开发从PSSC中回收磷的工艺具有潜力。
