CDFU Cyclonic Dissolved Gas Flotation Technology: An Innovative Solution for Difficult Oily Wastewater Treatment

1. Flotation Technology: A Core Separation Technology in Industrial Water Treatment

Flotation (Dissolved Air Flotation, DAF) is an efficient solid-liquidand liquid-liquid separation technology in water treatment. Its core mechanism is to use fine bubbles as carriers that adhere to suspended particles, oil droplets and colloids in the water to form“bubbleparticle complexes”with a density lower than water, which rapidly rise to the surface under buoyancy to form scum, achieving pollutant separation and water purification by mechanical scraping. With advantages such as high treatment efficiency, a small footprint and flexible operation, this technology has become one of the core processes for treating oily wastewater, high-turbidity wastewater and hard-to-degrade wastewater.

1. Mainstream Classification and Technical Features

According to the way bubbles are generated, flotation technology can be divided into the following four categories, suited to different water quality scenarios:

2. Core Application Fields

Flotation technology now covers many industries, with industrial oily wastewater treatment being the core application scenario, specifically including:

• Oilfield water treatment: produced water, fracturing flowback fluid, offshore platform wastewater (core treatment process);

• Refining industry: electric desalting wastewater, tank farm black water, sour water (high oil content, highly emulsified);

• Other fields: food processing, papermaking, electroplating heavy metal wastewater, landfill leachate and more.

3. Technology Development Trends

Flotation technology is currently evolving toward high efficiency, intelligence, modularization and customization:

• Ultra-fine bubble technology: bubble size reduced to5-30μm, improving the collision and adhesion efficiency with emulsified oil droplets, with single-stage oil removal rate exceeding90%;

• Material upgrades: key components use corrosion-resistant materials such as duplex stainless steel and titanium alloy, adapting to high-salt and highly corrosive conditions (such as offshore platforms and high-salinity oilfield water);

• Process integration: cyclonic centrifugal+and dissolved gas flotation technologies merged, achieving“physical demulsification+and efficient separation”simultaneously;

• Intelligent control:AIalgorithms adjust dissolved gas pressure and reflux ratio in real time, reducing energy consumption by22%or more, with remote O&M enabling unattended operation.

2. SINOKLECDFUCyclonic Dissolved Gas Flotation: An Innovative Solution for Difficult Oily Wastewater Treatment

SINOKLECDFU(cyclonic dissolved gas flotation unit) is a technological iteration built on conventionalCFUtechnology, with its core innovation being the deep integration of cyclonic centrifugal separation and dissolved gas flotation. It is designed specifically for difficult oily wastewater treatment in oilfields, refining and other sectors, solving the pain points of conventional flotation such as“difficulty removing emulsified oil, high energy consumption, a large footprint and poor corrosion resistance”.

1. Core Technical Advantages

(1) Ultra-fine bubbles+and cyclone dual core, for efficient demulsification and oil removal

• Bubble size is precisely controlled at5-30μm(median about25μm), perfectly matching1-10μmemulsified oil droplets, improving collision and adhesion efficiency by3times, with single-stage oil removal rate of>90%and suspended solids removal rate of>85%;

• The cyclonic centrifugal unit usesCFDoptimized flow field to achieve preliminary oil-water separation, while the dissolved gas flotation unit deeply removes residual emulsified oil, forming“a dual physical barrier”that thoroughly solves the stubborn emulsified oil problem.

(2) Purely physical demulsification, a dual breakthrough in environmental protection and cost reduction

• No chemical agents are added throughout the process, eliminating the generation of oily sludge (hazardous waste) at the source; the separated waste oil can be directly recovered and reused, reducing hazardous waste disposal costs by30%or more;

• with static equipment predominating and no mechanical slag scraping device, failure points and maintenance needs are reduced, extending the maintenance cycle to6months and reducing manual maintenance costs by50%

(3) Skid-mounted and+customized materials, adapting to harsh conditions

• With a compact skid-mounted design, the equipment volume is reduced by50%or more compared with conventional flotation, especially suitable for space-constrained scenarios such as offshore platforms and oilfield blocks, shortening the deployment period by40%;

• Key components use corrosion-resistant materials such as duplex stainless steel and titanium alloy, capable of withstanding high-salt, highly corrosive and high-temperature (<80℃) conditions, adapting to harsh offshore environments and high-salinity oilfield water treatment.

(4) Intelligent O&M, efficient and stable

• Equipped with an IoT intelligent control system, supporting remote monitoring, parameter adjustment and fault early warning, enabling unattended operation;

• shock load resistance reaches110%, remaining stably compliant even when influent water quality fluctuates, with effluent oil content controllable at≤10mg/L, suspended solids at≤20mg/L, meeting stringent domestic and international (such asIMO) discharge standards.

2. Core Performance Indicators

3. Typical Application Cases

Case1: produced water treatment project at an oilfield in Africa

• Treatment scale:5000m³/d;

• Influent water quality: large fluctuations in oil content, severe emulsification;

• Treatment effect: effluent oil content stable at<10mg/L, far better than industry standards, with stable equipment operation and reduced maintenance costs60%

Case2: tank farm black water treatment project at a petrochemical enterprise in Xinjiang

• Treatment scale:3600m³/d;

• Technical solution:CDFUsingle-stage treatment;

• Core results: shock load resistance reaches110%, operating energy consumption reduced by40%, effluent oil content of<15mg/L, meeting refining wastewater discharge standards.

Case3: PetroChinapetrochemical electric desalting wastewater treatment project

• Treatment scale:2400m³/d;

• Technical solution: two-stageCDFUcombined process;

• Treatment effect: effluent oil content of≤10mg/L, suspended solids of≤5mg/L, achieving wastewater reuse and compliant discharge.

3. SINOKLECDFU: The Preferred Solution for Oilfield and Refining Water Treatment

SINOKLECDFU, with its three core advantages of technological innovation, stable performance and environmental cost reduction, has become a benchmark product for oilfield produced water and refining high-oil-content wastewater treatment, especially suited to the following scenarios:

1.Offshore oilfield platforms: space-constrained, highly corrosive, unattended conditions; the skid-mounted design and corrosion-resistant materials are a perfect match;

2.Highly emulsified oily wastewater: refining sour water and fracturing flowback fluid; purely physical demulsification technology efficiently removes stubborn emulsified oil;

3.High-salinity water treatment: oilfield reinjection water and high-salinity wastewater; duplex steel and/titanium alloy materials withstand high-salt corrosion, extending equipment life;

4.Old project retrofits: no large-scale infrastructure needed; the modular quick-install design shortens the retrofit cycle and rapidly boosts treatment capacity.

In process design and solution bidding in the environmental engineering field, SINOKLECDFUis not only a highly efficient treatment device, but also a technical highlight that enhances project competitiveness --its innovative cyclone+and flotation process, , purely physical environmental characteristicsand intelligent O&M capability can significantly strengthen the technical advancement and feasibility of a solution, helping projects win bids and operate stably over the long term.