Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 28#, 310023, Hangzhou, China.
Institute of Thermal and Power Engineering, Zhejiang University of Technology, Liuhe Road 28#, 310023, Hangzhou, China.
J Hazard Mater. 2020 May 5;389:122045. doi: 10.1016/j.jhazmat.2020.122045. Epub 2020 Jan 10.
This study investigated the presence and concentration of 16 U.S. EPA priority controlled PAHs in gas, bio-oil and residues from the pyrolysis of different sewage sludges. We studied the temperature as a key influential factor for the formation of 16 targets PAHs and the effect of sludge source on the distribution of different molecules' PAHs were analyzed. Results showed that most of the 16 PAHs were formed during sludge pyrolysis and mainly ended up in bio-oil and gas. The distribution of PAHs in bio-oil was mostly dependent on pyrolysis temperature. With the increase of pyrolysis temperature from 450℃ to 850℃, it has been observed an increase of PAHs concentration in the bio-oils as follows: 16 % (ISS), 1.3 % (food manufacture wastewater sludge, FSS), 194 % (printing and dyeing wastewater sludge, PDSS), 334 % (DSS). 2, 3 and 4-ring PAHs dominate, and their total mass proportion is over 70 %. In gas, the types and concentrations of PAHs were less than in bio-oil. PAHs yield in solid was very low, and a trace content of PAHs of 0.0161 mg kg was detected from the solid after the pyrolysis of DSS, while PAHs in solid for ISS and FSS are even non-existent and would cause fewer environmental problems.
本研究调查了不同污水污泥热解过程中气体、生物油和残渣中 16 种美国环保署优先控制的多环芳烃（PAHs）的存在和浓度。我们研究了温度作为影响 16 种目标 PAHs 形成的关键因素，并分析了污泥来源对不同分子 PAHs 分布的影响。结果表明，大多数 16 种 PAHs 是在污泥热解过程中形成的，主要存在于生物油和气体中。生物油中 PAHs 的分布主要取决于热解温度。随着热解温度从 450℃升高到 850℃，生物油中 PAHs 的浓度呈如下变化：ISS 增加 16%，FSS 增加 1.3%，PDSS 增加 194%，DSS 增加 334%。2、3 和 4 环 PAHs 占主导地位，其总质量比例超过 70%。在气体中，PAHs 的种类和浓度低于生物油。固相中的 PAHs 产率很低，从 DSS 热解后的固相中检测到痕量的 0.0161mg/kg 的 PAHs，而 ISS 和 FSS 的固相中的 PAHs 甚至不存在，因此会造成较少的环境问题。
