煤焦化残渣污染特性与环境风险研究

以某煤焦化企业生产过程产生的焦油渣、煤焦油、硫铵酸焦油、焦粉、剩余污泥5种残渣为研究对象，采用气相色谱-质谱联用仪分析残渣中16种优先控制的多环芳烃（PAHs）浓度和环数分布，采用电感耦合等离子体质谱仪测定8种重金属浓度，通过计算残渣的苯并[a]芘（BaP）等效毒性和重金属潜在生态危害指数分析煤焦化残渣的环境风险。结果表明，5种残渣的PAHs总浓度为0.94~238 367 mg/kg，表现为煤焦油>焦油渣>硫铵酸焦油>焦粉>剩余污泥，焦油渣、煤焦油、硫铵酸焦油中高致突变性物质、致癌性物质浓度超过GB 5085.6—2007《危险废物鉴别标准 毒性物质含量鉴别》标准限值；焦油渣、煤焦油、焦粉、剩余污泥中Zn浓度最高，硫铵酸焦油中As浓度最高；5种残渣的BaP等效毒性为0.31~9 586.96 mg/kg，煤焦油、焦油渣、硫铵酸焦油具有更高的致癌风险；Hg是5种残渣中潜在环境风险最大的重金属，5种残渣对土壤均具有很强的潜在生态风险。

Study on pollution characteristics and environmental risk of coal coking residues

The tar slag, coal tar, ammonium sulfate tar, coke powder and residual sludge were collected from a coal coking enterprise. The concentrations and different ring distribution of 16 priority controlled polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography-mass spectrometry (GC-MS), and 8 heavy metals were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Meanwhile, the environmental risks of coal coking residues were analyzed by calculating the BaP equivalent toxicity concentration and the potential ecological risk index of heavy metals. The results showed that the total PAHs concentrations of five residues ranged from 0.94 mg/kg to 238 367 mg/kg, with the order of coal tar > tar slag > ammonium sulfate tar > coke powder > residual sludge, and the concentrations of highly mutagenic and carcinogenic compounds in tar slag, coal tar and ammonium sulfate tar exceeded the limits of Identification Standards for Hazardous Wastes- Identification for Toxic Substance Content (GB 5085.6—2007). The concentration of Zn in tar slag, coal tar, coke powder and residual sludge was the highest, and ammonium sulfate tar had the highest concentration of As. The BaP equivalent toxic concentration of the five residues was 0.31-9 586.96 mg/kg, and coal tar, tar slag and ammonium sulfate tar had higher cancer risk. Hg had the highest potential environmental risk among the five residues, and all the five residues had a strong potential ecological risk to the soil.