As oilfields worldwide enter the high water-cut stage, produced water treatment has been upgraded from a supporting link to the key to stable production. Industry data show that the comprehensive water cut of domestic mature oilfields generally exceeds 80%, and some blocks even reach 95%, generating tens of millions of cubic meters of oily wastewater every day. Moreover, the spread of enhanced oil recovery (EOR) technology has made produced water quality increasingly complex; problems such as stable emulsified oil that is hard to break, high-salinity and high-hardness scaling, residual refractory organics, and severe membrane fouling have become bottleneck issues constraining oil and gas production.

As a national high-tech enterprise focused on difficult industrial wastewater treatment, SINOKLE Technology uses its independently developed CDFU swirl dissolved air flotation, CDOF catalytic ozone oxidation, and KFM activated filter media filtration as three core technology engines to build a pure-physical, chemical-free treatment system, providing oilfield customers at home and abroad with full-process solutions covering compliance plus upgrading plus reuse, and achieving a dual breakthrough of stable compliance and cost reduction with efficiency improvement under complex conditions.

1. Industry Dilemma: Four Core Pain Points Constraining Oilfield Water Treatment Performance

Stable emulsified oil is hard to break, limiting separation efficiency

Produced fluid in the high water-cut stage forms a dual oil-in-water / water-in-oil emulsion system, with oil droplets mostly 0.1-10 microns in diameter, and conventional static settling has a separation efficiency of less than 50%. Surfactants and polymers introduced by chemical and polymer flooding greatly reduce interfacial tension and significantly increase emulsion stability, so effluent oil content often reaches 15-20 mg/L, far exceeding the double-5 standard (oil 5 mg/L or less, suspended solids 5 mg/L or less). Traditional demulsifiers not only increase costs but also produce large amounts of oily sludge hazardous waste, with persistently high disposal fees.

High-salinity, high-hardness wastewater: a dual dilemma in treatment and reinjection

The TDS of produced water is generally high, and even higher under extreme conditions, which makes conventional biological processes almost ineffective. Cations such as calcium, magnesium, barium, and strontium readily form sparingly soluble salts, causing severe scaling of pipelines and membrane modules, sharply reducing membrane flux and greatly shortening cleaning cycles. Thermal desalination is energy-intensive, membrane processes foul easily, and ion exchange resins require frequent regeneration, so treatment performance and operating costs have long been caught in a dilemma.

Refractory organics and toxic substances: escalating treatment challenges

Produced water contains sulfides, phenols, heavy metals, residual polymers, and other pollutants with relatively strong biological toxicity. Traditional biological methods have low removal rates for high-molecular-weight polymers, while chemical oxidation consumes large amounts of chemicals, costs a lot, and produces large amounts of sludge. High-sulfur conditions not only corrode equipment but also inhibit microbial activity, requiring additional desulfurization pre-treatment and further increasing treatment stages and costs.

High O&M costs and insufficient system stability

Oilfield produced water quality fluctuates widely, equipment corrosion and scaling are prominent problems, and membrane module replacement accounts for a high proportion of total investment, leading to a high rate of unplanned shutdowns. At the same time, there is a shortage of composite oil-gas-water treatment talent, and traditional processes have low automation and require frequent manual intervention, further pushing up overall operating costs.

2. SINOKLE's Breakthrough: Three Core Technologies Building a Pure-Physical Treatment Matrix

 CDFUSwirl dissolved air flotation: chemical-free demulsification and efficient separation of emulsified oil

SINOKLE's patented CDFU technology deeply integrates swirl centrifugal force with micro/nano-bubble dissolved gas technology, cracking the emulsification problem through a three-stage separation mechanism: the first stage uses swirl centrifugation to rapidly separate large oil droplets and suspended solids; the second stage uses micro-bubble collision to aggregate submicron oil droplets; and the third stage uses density-difference flotation to complete thorough oil-water separation.

This technology is a pure-physical, chemical-free process requiring no demulsifier or flocculant, eliminating secondary pollution at the source and producing no oily sludge hazardous waste. The oil-water separation rate can reach over 95%, effluent oil content is stably reduced to below 5 mg/L, and suspended solids removal is excellent. It also has strong shock resistance, adapting to complex conditions with large fluctuations in influent oil content, and features a small footprint, low energy consumption, and a shorter installation period.

CDOFCatalytic ozone oxidation: deep degradation of refractory organics

For produced water with high polymer content, high sulfur content, and high COD, SINOKLE's CDOF technology achieves efficient oxidation of refractory organics through the synergy of catalysis, ozone, and micro-bubbles. The patented multi-metal catalyst greatly improves ozone utilization and generates large numbers of hydroxyl radicals; micro-bubbles enhance mass transfer efficiency and shorten reaction time; and refractory substances such as polymers and surfactants can be degraded in a targeted manner, effectively improving wastewater biodegradability.

In shale oil fracturing flowback fluid treatment, this technology can efficiently reduce polymer concentration and wastewater viscosity, creating favorable conditions for subsequent treatment, with a treatment cost clearly lower than that of traditional advanced oxidation methods.

KFM activated filter media filtration: final-stage control ensuring reinjection water quality

SINOKLE's independently developed KFM activated filter media, through special preparation and modification, forms a dual purification mechanism of negative-charge adsorption and deep filtration, powerfully adsorbing colloids, suspended solids, and tiny oil droplets. It offers high filtration precision, and the effluent quality can meet the reinjection requirements of low-permeability oilfields. The filter media has high backwash efficiency and a long service life, far superior to traditional media, and can stably guarantee reinjection water quality over the long term, avoiding formation pore blockage.

3. Full-Process Solutions: Customized Processes for Different Operating Conditions

Conventional produced water treatment: three-phase separation + CDFU+KFM

The process flow is produced fluid -> three-phase separator -> CDFU swirl dissolved air flotation -> KFM activated filter media filtration -> compliant reinjection. This is a pure-physical process with no chemical addition and low comprehensive treatment cost; the effluent stably meets the double-5 standard, and it is suitable for conventional oilfields with a water cut of 70-90%.

High-polymer / high-sulfur produced water: CDFU+CDOF+KFM

The process flow is produced fluid -> two-stage CDFU→CDOF catalytic ozone oxidation -> KFM filter -> advanced reinjection. This process effectively solves the problems of residual polymer and sulfide corrosion, with excellent COD and sulfide removal performance, and is suitable for chemical-flooding / polymer-flooding oilfields and high-sulfur oilfields.

Shale oil fracturing flowback fluid: CDOF+CDFU+ membrane separation

The process flow is flowback fluid -> CDOFcatalytic oxidation gel breaking -> two-stage CDFU de-oiling -> ultrafiltration -> reverse osmosis -> reuse / reinjection. This process enables a high proportion of fracturing fluid reuse, reduces fresh water consumption, and significantly lowers treatment costs compared with traditional processes; it is suitable for shale oil / gas development blocks.

Offshore platforms / remote well sites: modular CDFU+ intelligent control system

The process flow is produced fluid -> modular CDFU unit -> KFM filter -> compliant discharge / reinjection. The skid-mounted design has a small footprint and allows quick installation and unattended operation; effluent indicators are better than relevant international discharge standards, and O&M costs are greatly reduced.

4. Value Empowerment: From Compliance to Upgrading, Achieving Triple Benefit Improvement

Environmental benefits: from compliant discharge to green circulation

The pure-physical process adds no chemicals, reducing hazardous waste generation at the source and greatly lowering sludge disposal costs; the reuse rate of high-salinity wastewater is significantly increased, reducing fresh water consumption; and the intelligent control system monitors discharge indicators in real time, ensuring compliant and stable operation and avoiding environmental penalty risks.

Economic benefits: from high input to high return

Compared with traditional processes, SINOKLE's pure-physical process achieves large reductions in chemical costs and sludge disposal costs, with energy and O&M costs lowered simultaneously, so the comprehensive water treatment cost drops noticeably. Multiple oilfield application cases show that after adopting SINOKLE's process, projects can save millions to tens of millions of yuan in operating costs each year.

Production benefits: from passive treatment to proactive empowerment

Stably compliant reinjection water effectively avoids formation damage, helping to improve crude oil recovery and extend the oilfield development cycle; the intelligent control system reduces manual intervention and lowers the rate of unplanned shutdowns, ensuring continuous and stable oil and gas production; and the modular design can be adapted to marginal oilfields and scattered well sites, enabling nearby treatment and on-site reinjection and reducing water transmission costs.

5. Technological Innovation: Building Core Competitiveness for Sustainable Development

As a national high-tech enterprise, SINOKLE holds multiple invention patents, PCT international patents, and utility model patents, forming a complete technology protection system. The company's R&D team continuously iterates in directions such as separation technology, catalytic oxidation, and intelligent control, constantly optimizing materials and processes, and integrating IoT and AI technologies to build a cloud monitoring platform, further reducing O&M costs.

In overseas markets, SINOKLE's technology has been successfully applied to oilfield projects in Africa, the Middle East, and other regions, adapting to international standards and local operating conditions and setting a good example for Chinese water treatment technology going global.

Conclusion: Leading a New Future for Oilfield Water Treatment through Technological Innovation

Facing the complex challenges of global oilfield water treatment, SINOKLE Technology takes pure-physical, chemical-free, and intelligent as its core direction and, relying on CDFU, CDOF and KFM as three core technologies, provides the industry with efficient, environmentally friendly, and economical full-process solutions, realizing the shift from passive compliance to proactive upgrading and continuously injecting momentum into green oil and gas production.

In the future, SINOKLE will continue to deepen its work in oilfield water treatment, focusing on emerging scenarios such as unconventional oil and gas development and CCUS-supporting water treatment, driving the industry to upgrade toward resource recovery, low-carbon operation, and intelligence, and contributing Chinese technology and Chinese solutions to the sustainable development of the global energy industry.