Skid-Mounted Mobile Solution Breaks the Oilfield Produced Water Treatment Bottleneck
In the development of mature oilfields worldwide, waterflooding is widely used across production scenarios as a core means of enhancing oil recovery. However, long-term waterflooding has created a thorny industry problem — the water cut of produced fluids rises sharply, and treating large volumes of oil-bearing produced water has become a key bottleneck restricting efficient, green oilfield operations. Some oilfields operate in a dispersed, multi-point mode, with each block producing only 300–500 bbl/d, and conventional fixed wastewater treatment equipment cannot meet the need for small-batch, multi-point, relocatable treatment. Problems such as low treatment efficiency, high operating costs and mounting pressure to meet environmental standards are becoming ever more prominent.
To address the core pain points of produced water treatment in mature oilfields, Shenzhen SINOKLE Technology Co., Ltd., drawing on its self-developed core water treatment technology, has purpose-built a two-stage CDFUcyclonic dissolved-air flotation + KFM filter skid-mounted mobile treatment unit. With the advantages of integrated design, flexible relocation, efficient purification and intelligent operation and maintenance, it offers a brand-new solution for produced water treatment in dispersed oilfield blocks, successfully cracking the industry dilemma of produced water treatment in mature oilfields.
SINOKLE's skid-mounted mobile produced water treatment unit is an integrated device designed specifically for dispersed oilfield production. The complete set of core treatment units is housed in a 40-foot standard container, enabling factory prefabrication, complete skid assembly and plug-and-play on site. The designed treatment capacity is 3 m³/h, the overall dimensions are 12000 mm × 2350 mm × 2690 mm, the skid weighs 12000 kg net and 21000 kg in operation. Compact and moderate in weight, it can be transported quickly by conventional means and moved immediately to the next block after finishing one, allowing continuous operation. It is a perfect fit for oilfield production modes such as the Carmo field with multiple dispersed points and small-batch water production, completely solving the problems of immobility, long deployment cycles and poor adaptability of conventional equipment.
In terms of core treatment process, the unit uses a purely physical combination of two-stage CDFUcyclonic dissolved-air flotation + KFM modified activated filter media filters. No chemical agents are added throughout the process, which avoids secondary pollution from chemicals, greatly reduces operating costs and ensures stable compliant effluent. According to the design specifications, the influent oil content is ≤2500 mg/L and suspended solids ≤150 mg/L; after treatment the effluent oil content is ≤10 mg/L and suspended solids ≤5 mg/L, with pH stably maintained at 6–9. This fully meets the stringent requirements for produced water reinjection and environmental discharge, enabling water recycling and supporting green oilfield production.
As the core oil removal stage of the unit, the two-stage CDFUcyclonic dissolved-air flotation is a patented technology independently developed by SINOKLE, combining the advantages of cyclonic centrifugal separation and dissolved-air flotation separation. With a flow field design optimised through CFD simulation, it delivers a highly efficient, fast oil removal unit. The device uses a vertical-tank sealed pressurised structure with an operating pressure of 0.05–0.08 MPa. Its twin tangential inlets create a stable, uniform cyclonic flow field and generate 5–30 μm ultra-fine micro-nano bubbles that rapidly collide and attach to dispersed oil, emulsified oil and suspended solids, achieving efficient demulsification, coalescence and flotation separation. The unit also incorporates an internal central cylinder and guide vanes that divide the flotation space into multiple zones, together with a bottom cyclonic desanding design that effectively removes sand and silt while removing oil. It has strong resistance to shock loads, tolerating 50% flow fluctuations, and its separation efficiency far exceeds conventional flotation equipment. SINOKLE currently holds a number of CDFUrelevant patents and one software copyright, with technology reaching international advanced standards.
The KFM modified activated filter media filter serving as the deep purification stage is the key to effluent precision. It uses super-hydrophilic modified quartz activated filter media manufactured through 60 processing steps. The media surface carries a negative charge and has hydrophilic, oil-repellent and oxidative purification characteristics, forming super-hydrophilic micro-nano pores that efficiently capture small oil droplets and suspended solids. Compared with conventional media such as anthracite and emery, KFM media has high mechanical strength, a wear rate of ≤0.2% and a breakage rate of ≤0.5%. Its resistance to oil contamination is extremely strong and it is not prone to compaction or blockage. Backwash efficiency can reach 100% and the media service life exceeds 15 years, five times that of conventional media. In addition, the KFM filter replaces conventional multi-stage filtration with single-stage filtration, reducing the footprint by 20%–30%. The backwash differential pressure is 0.1–0.15 MPa and each backwash takes only 10 minutes; the backwash effluent can be returned to the upstream produced water tank for recirculation, further improving water resource utilisation.
In terms of operation and maintenance, SINOKLE's skid-mounted mobile unit achieves intelligent, automated operation across the whole process, greatly reducing labour costs and maintenance difficulty. The unit uses a three-layer PLC + SCADA intelligent control system comprising a field control layer, a monitoring layer and a management layer. It collects water quality, flow, pressure and level parameters in real time and automatically completes the full sequence of operations including water intake, air dissolution, oil discharge, gas venting, filtration and backwash. Level control automatically governs water and oil discharge, pressure control automatically regulates gas intake and venting, and the filter automatically triggers backwash based on differential pressure — no frequent manual intervention is needed and a single operator can manage the unit.
The unit is also equipped with remote and mobile monitoring systems supporting multi-terminal access via web client, mobile app and WeChat mini program, allowing real-time viewing of equipment status, water quality data and alarm information as well as remote start/stop, parameter adjustment and fault diagnosis. The data centre uses distributed storage and encryption technology and can automatically generate daily and monthly operating reports. Through big data analysis it predicts equipment faults and water quality trends, providing early warnings and optimising operating strategies, making oilfield water treatment operation and maintenance smarter, more efficient and safer.
Operating cost is a core consideration in oilfield equipment selection, and this mobile unit from SINOKLE achieves extremely low operating costs thanks to its purely physical process and efficient, energy-saving design. Calculations show that the unit's total continuous operating power is 17.5 kW; at an electricity price of ¥0.5/kWh, the electricity cost per tonne of water treated is only ¥1.934. No chemicals are added at all, eliminating large chemical costs. The filter media service life exceeds 5 years with no frequent replacement cost, and only routine wear parts such as pump sets and purification air systems need periodic replacement. Automated operation also greatly saves labour costs. Overall operating cost is far lower than conventional produced water treatment equipment, offering a clear cost-performance advantage.
Thanks to its excellent treatment performance and practical characteristics, SINOKLE's skid-mounted mobile produced water treatment unit has been successfully deployed in multiple oilfield projects and is highly recognised by the industry. Against the backdrop of the global energy industry's transition to green, low-carbon operation, efficient treatment and recycling of oilfield produced water has become an inevitable requirement for sustainable oilfield development. With four core advantages — flexible relocation, efficient purification, intelligent operation and maintenance, and low-cost operation — SINOKLE's skid-mounted mobile produced water treatment unit precisely matches the production needs of dispersed blocks in mature oilfields. It solves the environmental challenge of produced water treatment while achieving water recycling, providing strong technical support for cost reduction, efficiency gains and green development in oilfields.
In the future, Shenzhen SINOKLE Technology will continue to deepen its work in oilfield water treatment, continually iterating and upgrading its core technologies and launching more innovative water treatment equipment suited to oilfield scenarios. With professional technology and quality service, it will help oilfields worldwide achieve efficient, environmentally friendly and sustainable development goals, contributing technological strength to the green development of the energy industry.
