Method and system for treatment of organic contaminants by coupling Fenton reaction with membrane filtration

An organic contaminants wastewater treatment method, comprising:

• receiving from an external source wastewater that contains organic contaminants;
• adjusting pH value of the received wastewater by acidic reagents and dosing the received wastewater with ferrous reagents;
• adding H2O2 into the pH-adjusted and ferrous-dosed wastewater for Fenton reaction;
• purging the H2O2 from the Fenton reaction-treated wastewater;
• adjusting the pH value of the H2O2-purged wastewater by a caustic reagent;
• wherein the pH value of the caustic reagent-treated wastewater is in the range of 7-10;
• thereby iron (III) becomes insoluble to form iron (III) complexes in the form of iron hydroxide;
• filtering the caustic reagent-treated wastewater by filtration membrane to produce filtrate (i.e. water) and retain the iron (III) complexes and solids within a membrane tank housing the microfiltration or ultrafiltration membrane modules;
• wherein the membrane is operated at Trans-membrane Pressure (TMP) in the range of 10-30 kPa;
• recirculating the iron (III) complexes and solids at a recirculation rate to the step of adjusting pH value of the received wastewater by acidic reagents and dosing the received wastewater with ferrous reagents;
• wherein recirculation rate is in range of 50%-700% wastewater flow rate;
• and wherein the wastewater flow rate is the flowrate of wastewater entering the step of adjusting pH value of the received wastewater by acidic reagents and dosing the received wastewater with ferrous reagents;
• acidic cleaning the microfiltration or ultrafiltration membranes using a mixture of acid and water, wherein the water is from the filtering step;
• and
• caustic cleaning the microfiltration or ultrafiltration membranes using a mixture of caustic reagent and water, wherein the water is from the filtering step.