Table 1.
Geochemical characteristics of produced water from the upstream (UCPW) and downstream (DRW) of a shale gas production facility in Barnett Shale formations (Figure 1).
| Samples | Sampling time | pH | Sulfate (mM) | Fe2+ (mM) | Sulfide (mM) | Thiosulfate (mM) | Salinity (Cl- g/L) | Acetate (mM) |
|---|---|---|---|---|---|---|---|---|
| Upstream(UPCW) | July 2012 | 7.0 | 0.74 | 1.73 | 0.04 | BDLa | 117 | NRb |
| September2012 | 6.8 | 1.84 | 0.73 | BDL | BDL | 46.8 | 0.5 | |
| Downstream(DRW) | July 2012 | 6.5 | 0.79 | NR | 0.25 | BDL | 19.7 | NR |
| September2012 | 7.0 | 1.93 | 11.76 | BDL | 0.17 | 16.9 | 170 |
aBDL, below detection level (5 ppm); bNR, data not recorded.