Fracturing Flowback Fluid Treatment Process
Process Overview
Process Introduction
After fracturing flowback fluid returns to the surface, it enters a collection tank/pit where large-particle solids such as sand are removed by gravity sedimentation. It is then pumped to the CDOF unit for advanced oxidation and viscosity reduction. A catalyst is injected before the CDOF unit to enhance the oxidation effect. After gel breaking, a dedicated flocculant is added to the flowback fluid before it enters the CDFU unit for flotation. Sludge from both the CDOF and CDFU units enters a screw press for dewatering; the dewatered liquid returns to the collection tank/pit. The CDFU product water enters a filter, and the filtered water meets the requirements for reuse in fracturing fluid preparation.
CDOF ozone catalytic advanced oxidation for gel breaking and viscosity reduction + CDFU cyclone dissolved-air flotation for efficient oil and solids removal + precision filtration — skid-mounted equipment can be truck-mounted for on-site wellsite operations; filtered water meets requirements for reuse in fracturing fluid preparation.
Schematic Diagram of Fracturing Flowback Fluid Treatment Process Flow
Technological Advantages
Technological Advantage
Short process flow, skid-mounted equipment, can be truck-mounted for wellsite operations, flexibly adapting to oilfield field requirements
CDOF is a proprietary patented unit; rapid and thorough oxidation enables fast gel breaking and viscosity reduction, with efficient COD removal
Effectively removes calcium, magnesium, and boron ions; sludge volume significantly reduced, lowering downstream treatment difficulty
Retention time only 1/5 of conventional processes, footprint only 1/3, saving capital and space
Enclosed equipment operation, safe and environmentally compliant, fully automated, reducing manual operation and maintenance
CDFU product water after precision filtration meets requirements for reuse in fracturing fluid preparation, achieving water resource recycling
Technical Comparison
Technical Comparison
| Comparison Item | Conventional Flocculation + Biological Treatment | CDOF + CDFU Integrated System |
|---|---|---|
| Gel Breaking & Viscosity Reduction | Chemical gel breaking is unstable and time-consuming; difficult to achieve thorough viscosity reduction | CDOF patented catalytic oxidation: rapid and thorough gel breaking, significant viscosity reduction |
| Treatment Process | Long process, multi-stage structures, long retention time (hours to days) | Short process, skid-mounted integrated system, retention time only 1/5 of conventional |
| Footprint | Large footprint, requires new concrete structures | Skid-mounted design, footprint only 1/3 of conventional, truck-mountable for wellsite operations |
| Sludge Generation | High chemical dosing, large sludge generation, high hazardous waste disposal cost | Sludge volume greatly reduced, no hazardous waste generated, lower disposal cost |
| Ca/Mg/B Removal | Difficult to effectively remove calcium, magnesium, and boron ions | Effectively removes calcium, magnesium, and boron ions, producing excellent effluent quality |
| Operation Mode | High manual workload, difficult to automate, high O&M cost | Fully enclosed automated operation, remote monitoring capable, low O&M cost |
Application Cases
Application Case
Xinjiang Karamay Oilfield — Fracturing Flowback Fluid Treatment Project
