[Treatment of simulated produced wastewater from polymer flooding in oil production using dithiocarbamate-type flocculant].

A dithiocarbamate flocculant, DTC (T403), was prepared by the reaction of amine-terminated polyoxypropane-ether compound known as Jeffamine-T403 and carbon disulfide in alkaline solution. The oil removal efficiency of DTC (T403) for simulated produced wastewater from polymer flooding in oil production was studied by Jar-test. The effect of the dosage of DTC (T403), hydrolyzed polyacrylamide (HPAM), Fe2+ and Fe3+ ions, and pH on the oil removal efficiency of DTC (T403) was investigated. The results showed that the chelate polymer formed by DTC (T403) and Fe2+ ion has good oil removal performance by net capturing mechanism. HPAM had a negative effect on oil removal efficiency of DTC (T403). For the treatment of the simulated wastewater containing 0-900 mg/L of HPAM and 300 mg/L of oil, the residual oil concentrations in water samples decreased below 10 mg/L when the dosage of Fe2+ and DTC (T403) was 10 mg/L and 25 mg/L, respectively. The oil removal efficiency of DTC (T403) was affected by pH and good oil removal efficiency was obtained when the pH was below 7.5. DTC (T403) is appropriate for the treatment of oily wastewater containing Fe2+ ion.