Abstract: A method for treating produced water in a system for treating wastewater is disclosed. The system includes a reverse osmosis unit for removing dissolved solids. The reverse osmosis unit produces a permeate and concentrate. To reduce the fouling potential of the membranes associated with the reverse osmosis unit and/or to increase membrane lifetime and/or to increase system recovery, at least a portion of the concentrate is recycled and mixed with the wastewater stream at a point upstream of the reverse osmosis unit.

Abstract: A method for treating produced water in a system for treating wastewater is disclosed. The system includes a reverse osmosis unit for removing dissolved solids. The reverse osmosis unit produces a permeate and concentrate. To reduce the fouling potential of the membranes associated with the reverse osmosis unit and/or to increase membrane lifetime and/or to increase system recovery, at least a portion of the concentrate is recycled and mixed with the wastewater stream at a point upstream of the reverse osmosis unit.

Abstract: A method of treating produced water, such as frac flowback, that includes pre-treating the produced water which is followed by a crystallization process that produces a condensate that typically includes ammonia and benzene. The ammonia and benzene concentration is reduced by biologically nitrifying and denitrifying the condensate. This produces an effluent that is directed to a solids-liquid separation process that removes suspended solids. The solids-liquid separation process produces another effluent that is subjected to a benzene polishing process that further reduces the benzene concentration of the effluent produced by the solids-liquid separation process.

Abstract: A method of treating produced water, such as frac flowback, that includes pre-treating the produced water which is followed by a crystallization process that produces a condensate that typically includes ammonia and benzene. The ammonia and benzene concentration is reduced by biologically nitrifying and denitrifying the condensate. This produces an effluent that is directed to a solids-liquid separation process that removes suspended solids. The solids-liquid separation process produces another effluent that is subjected to a benzene polishing process that further reduces the benzene concentration of the effluent produced by the solids-liquid separation process.

Abstract: A method of recovering oil from an oil-bearing formation including recovering an oil-water mixture from the oil-bearing formation and separating produced water from the oil-water mixture. The produced water includes phosphonate anti-scalant compounds. An oxidant is mixed with the produced water to deactivate the phosphonate anti-scalant compounds, thereby permitting dissolved solids in the produced water to precipitate. After deactivating the phosphonate anti-scalant compounds, the produced water is directed into a ceramic membrane which filters the produced water, producing a permeate stream and a retentate stream having suspended solids and precipitants therein.