Treatment of production water from oil fields using chemically assisted recovery

Treatment equipment comprising at least two nutshell filters, a first nutshell filter comprising filtering media housed within a first container and a second nutshell filter comprising filtering media housed within a second container, in series, said first nutshell filter having the capacity to receive production water, said production water:

• being viscosified by polyacrylamides;
• and
• having a hydrocarbon concentration in excess of 150 mg/L,
• wherein the first nutshell filter recovers a majority of oil from the production water, and water proceeds out of the first nutshell filter and subsequently into the second nutshell filter, which serves as a finisher, and wherein water leaving the second nutshell filter remains viscosified by polyacrylamides.