Chang Yu-Chen, Chen Ting-Yu, Tsai Yung-Pin, Chen Ku-Fan
Department of Civil Engineering, National Chi Nan University 1 Univ. Rd., Puli Nantou 54561 Taiwan
Department of Landscape Architecture, National Chin-Yi University of Technology Taiping Taichung 41170 Taiwan.
RSC Adv. 2018 Jan 10;8(5):2433-2440. doi: 10.1039/c7ra10860e. eCollection 2018 Jan 9.
This study uses a trichloroethene (TCE)-contaminated site to determine the efficacy of persulfate oxidation for the treatment of TCE-contaminated groundwater. The main objectives of this study are: (1) to evaluate the efficacy of TCE treatment using persulfate with different injection strategies; (2) to determine the persistence of persulfate in the aquifer; (3) to determine the radius of influence (ROI) and transport distance of persulfate and (4) to determine the impact of persulfate on indigenous microorganisms during remediation. TCE concentrations are 0.26 mg L in P143 and 0.361 mg L in P146 and the microbial numbers are 6.1 × 10 CFU mL in P143 and 4.4 × 10 CFU mL in P146, before persulfate is injected. The results of the pilot study show that persulfate eliminates TCE. 100% of TCE is removed in P146 and 95% in P143. Single injection of a total amount of 275 kg of 5% persulfate produces better TCE removal than two half persulfate injections in sequence. The transport distance of persulfate ranges from 3.6 to 4.5 m. Persulfate also persists for 14 days in the aquifer. After persulfate is injected, the total bacterial counts decrease slightly to 2.4 × 10 CFU mL in P143 and 1.8 × 10 CFU mL in P146. When persulfate is consumed, the total bacterial counts increase but there is no recovery of the microbial community. The results show that sequential injections of a large amount of persulfate are suggested to maintain good long-term performance for TCE treatment.
本研究利用一个三氯乙烯（TCE）污染场地来确定过硫酸盐氧化法处理受TCE污染地下水的效果。本研究的主要目标是：（1）评估采用不同注入策略的过硫酸盐处理TCE的效果；（2）确定过硫酸盐在含水层中的持久性；（3）确定过硫酸盐的影响半径（ROI）和运移距离；（4）确定修复过程中过硫酸盐对原生微生物的影响。在注入过硫酸盐之前，P143中TCE浓度为0.26 mg/L，P146中为0.361 mg/L，P143中微生物数量为6.1×10 CFU/mL，P146中为4.4×10 CFU/mL。中试研究结果表明过硫酸盐可去除TCE。P146中100%的TCE被去除，P143中为95%。单次注入总量为275 kg的5%过硫酸盐比分两次依次注入半量过硫酸盐产生更好的TCE去除效果。过硫酸盐的运移距离在3.6至4.5 m之间。过硫酸盐在含水层中也能持续存在14天。注入过硫酸盐后，P143中的总细菌数略有下降至2.4×10 CFU/mL，P146中为1.8×10 CFU/mL。当过硫酸盐消耗殆尽时，总细菌数增加，但微生物群落未恢复。结果表明，建议依次大量注入过硫酸盐以保持TCE处理的良好长期性能。
