页岩气开发井场污染土壤可生化性研究

Study on Soil Biodegradability in Changning and Weiyuan National Shale Gas Area

以威远-长宁页岩气开发井场H6平台受污染土壤为例,分析其碳、氮、磷、有机烃类、石油类、重金属类含量与生物毒性,结合结果分析其生态修复性。数据表明,井场各区域土壤中的碳、氮、磷含量差异较大;土壤的有机质含量与含油率成正相关;石油类污染物的含量均未超过1%;一类重金属Ni、Cd超标,含量分别为210.19 mg/kg、6.53 mg/kg;除工作区域外,污染土壤生物毒性为微毒。结果表明,研究土壤具有可生化性,应有针对性地改善土壤条件,提高修复效率。

It is important to treat the polluted soil during shale gas operation with a green and harmless technology since it has gotten widely attention. The contaminated soils were collected form shale gas well H6 in Weiyuan-Changning,Sichuan,China,to detect the bioavailability by analyzing the soil properties and biotoxicity. The results showed that there were significantly differences between C,N and P in contaminated soils in which alkane occupied 0. 437%,alicyclic hydrocarbons were 0. 0411%,while the petroleum hydrocarbons were within 1%. Besides,the heavy metals,mostly Ni（ 210. 19 mg /kg） and Cd（ 6. 53 mg /kg） were out of limits. It was revealed that the contaminated soil beyond operational area was mildly toxic which directly indicated that the polluted soil in H6 was bioavailability. Therefore,ecological remediation,especially phytoremediation and microbial remediation, can be available technologies to enhance the degradation of contaminated soil by offering sufficient nutrients and ameliorate the soil properties.