There are two ways to remove organics, the oil and tar residue, from produced water in wells.
The most common involves chemical oxidizers such as Chlorine Dioxide which break the organics down into carbon dioxide. While the upfront equipment cost is low, the cost of the chemicals used is very high through the entire operation. The time to clear the wastewater from the wells is also very high.
Biotreatment uses the same microbes that are commonly used to clean up after oil spills at sea to completely digest the organics. These microbes can clear produced water in a matter of hours if there is sufficient oxygen present, so an aerator like the Aire-O2 Aspirator is needed. The operational costs are much lower and the resulting water can be much more easily recycled back to a hydraulic fracturing operation.
Chemical oxidizers are typically only cost effective for very small or temporary wells.
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