It has become increasingly attractive and necessary to reuse treated produced water for frac fluids, especially in remote locations or limited water sources regions to minimize freshwater usage. Eletrocoagulation (EC), a traditional water remediation technology, was recently introduced to oilfield application. However, the complicated components in produced water are challenging for traditional EC systems.
A new EC apparatus has exhibited cost-efficient remediation of produced water, especially in the removal of iron and suspended solids that have restricted concentration for making frac fluids. The unique EC system has demonstrated fast reduction in iron from over 900 ppm to less than 5 ppm from high-concentration oil contained water, and efficient removal of hydrogen sulfides (H2S), heavy metals, bacteria, and other contaminants. The system has been successfully used for treating produced water for numerous operators in the Permian Basin, reducing operating costs more than 20% while reducing freshwater demand and trucking over 90%.