SINOKLE’s CDFU: Advanced Cyclonic Dissolved-Gas Flotation Technology for Efficient Oily Wastewater Treatment

I. Flotation Technology: Core Separation Method in Industrial Water Treatment

Dissolved Air Flotation (DAF) is a high-efficiency solid-liquid or liquid-liquid separation technology in the water treatment field. Its core mechanism is the use of fine microbubbles as carriers, which adhere to suspended particles, oil droplets, colloids, and other contaminants in water to form “bubble-particle complexes” with a density lower than water. Under buoyancy, these complexes quickly rise to the surface to form a scum layer, which is mechanically removed to achieve contaminant separation and water purification. This technology has become a core process for treating oily wastewater, high-turbidity wastewater, and hard-to-degrade wastewater due to its high efficiency, small footprint, and flexible operation.

1. Main Categories and Technical Features

According to the method of bubble generation, flotation technology can be divided into the following four types, each suited to different water quality scenarios:

Types of Convensional Flotation Technologies

2. Core Application Areas

Flotation technology has been widely applied across multiple industries, with industrial oily wastewater treatment as a core scenario, including:

· Oilfield Water Treatment: Produced water, fracturing flowback, offshore platform sewage (core treatment process);

· Refining Industry: Electric desalting wastewater, tank farm black water, acidic wastewater (high oil, high emulsification);

· Other Sectors: Food processing, paper industry, heavy metal electroplating wastewater, landfill leachate, etc.

3. Technology Development Trends

Flotation technology is evolving towards high efficiency, intelligence, modularity, and customization:

· Ultrafine Bubble Technology: Bubble size reduced to 5–30 μm to enhance collision and adhesion with emulsified oil droplets, achieving single-stage oil removal rates over 90%;

· Material Upgrades: Key components use duplex stainless steel, titanium alloy, and other corrosion-resistant materials to handle high-salinity and highly corrosive environments (e.g., offshore platforms, high-salinity oilfield water);

· Process Integration: Cyclonic separation + dissolved air flotation integration achieves dual effects of “physical demulsification + efficient separation”;

· Intelligent Control: AI algorithms dynamically adjust dissolved air pressure and recirculation ratios, reducing energy consumption by over 22% and enabling remote unmanned operation.

II. SINOKLE’s Cyclonic Dissolved-gas Flotation Unit (CDFU): Innovative Solution for Challenging Oily Wastewater

Shenzhen Clear Science & Technology Co., Ltd (SINOKLE) developed the Cyclonic Dissolved-gas Flotation Unit (CDFU), an upgraded iteration of conventional CFU. Its core innovation lies in the deep integration of cyclonic centrifugal separation with dissolved-air flotation, specifically designed for challenging oily wastewater in oilfields and refineries. It effectively addresses the pain points of traditional flotation: difficulty removing emulsified oil, high energy consumption, large footprint, and poor corrosion resistance.

1. Core Technical Advantages

(1) Ultrafine Bubbles + Cyclonic Core: Efficient Demulsification and Oil Removal

· Bubble size precisely controlled at 5–30 μm (median ~25 μm), perfectly matching 1–10 μm emulsified oil droplets; collision and adhesion efficiency improved threefold, single-stage oil removal rate >90%, suspended solids removal rate >85%.

· Cyclonic centrifugal unit optimized via CFD achieves preliminary oil-water separation; dissolved air flotation unit deeply removes residual emulsified oil, forming a “dual physical barrier” to solve stubborn emulsified oil problems.

(2) Pure Physical Demulsification: Eco-friendly and Cost-Reducing

· No chemical additives throughout, eliminating oily sludge (hazardous waste) generation at the source; separated oily waste can be directly recycled, reducing hazardous waste disposal costs by over 30%.

· Mainly static equipment with no mechanical scum scraper, reducing failure points and maintenance needs; maintenance interval extended to six months, labor cost cut by 50%.

(3) Skid-mounted + Customized Materials: Adaptable to Harsh Conditions

· Compact skid-mounted design reduces equipment footprint by over 50%, ideal for offshore platforms or oilfield blocks with space constraints; deployment cycle shortened by 40%.

· Key components made of duplex stainless steel or titanium alloy, resistant to high salinity, corrosion, and temperatures <80°C, suitable for harsh offshore and high-salinity oilfield environments.

(4) Intelligent Operation & Maintenance: Efficient and Stable

· Equipped with IoT-based intelligent control system for remote monitoring, parameter adjustment, and fault warnings, enabling unmanned operation.

· Shock load resistance up to 110%, maintaining stable effluent quality even with influent fluctuations; oil content ≤10 mg/L, suspended solids ≤20 mg/L, meeting stringent domestic and international (IMO) discharge standards.

2. Core Performance Indicators

Performance Indicators

3. Typical Application Cases

Case 1: African Oilfield Produced Water Treatment

· Treatment Capacity: 5,000 m³/d;

· Influent Water Quality: High oil fluctuation, severe emulsification;

· Result: Effluent oil content <10 mg/L, far exceeding industry standards; stable operation, maintenance costs reduced by 60%.

Case 2: Xinjiang Petrochemical Tank Farm Black Water Treatment

· Treatment Capacity: 3,600 m³/d;

· Solution: Single-stage CDFU;

· Result: Shock load resistance 110%, energy consumption reduced 40%, effluent oil content <15 mg/L, meeting refinery wastewater discharge standards.

Case 3: CNPC Petrochemical Electric Desalting Wastewater Treatment

· Treatment Capacity: 2,400 m³/d;

· Solution: Two-stage CDFU process;

· Result: Effluent oil content ≤10 mg/L, suspended solids ≤5 mg/L, enabling wastewater reuse and compliant discharge.

III. CDFU of SINOKLE: Preferred Choice for Oilfield and Refinery Water Treatment

With three core advantages — technological innovation, stable performance, and eco-friendly cost reduction — CDFU has become a benchmark for oilfield produced water and high-oil refinery wastewater treatment, particularly suitable for:

1. Offshore Oil Platforms: Space-limited, high-corrosion, unmanned operation; skid-mounted design and corrosion-resistant materials perfectly match requirements.

2. Highly Emulsified Oily Wastewater: Refinery acidic water, fracturing flowback; pure physical demulsification efficiently removes stubborn emulsified oil.

3. High-salinity Water Treatment: Oilfield reinjection water, high-salinity wastewater; duplex steel/titanium alloy resists corrosion, extending equipment lifespan.

4. Old Project Upgrades: No large-scale civil work required; modular quick-install design shortens retrofit cycle and quickly enhances treatment capacity.

In environmental engineering process design and tender proposals, SINOKLE’s CDFU is not only a high-efficiency treatment device but also a technical highlight that enhances project competitiveness. Its cyclonic + flotation innovation, pure physical and eco-friendly operation, and intelligent operation & maintenance capabilities significantly improve technical sophistication and feasibility, supporting successful project bidding and long-term stable operation.