In the petroleum refining industry, electro-dehydration wastewater, due to its complex composition, severe emulsification, and poor biodegradability, has often been regarded as the “number one problem” affecting the stable operation of wastewater treatment systems. Directly entering the biological treatment system, it can easily cause microbial poisoning, sludge deactivation, and result in high treatment costs and fluctuating results. Based on a deep understanding of industry pain points, the Shenzhen Clear Science & Technology Co., Ltd (SINOKLE) has launched an innovative ozone advanced oxidation pretreatment technology to solve the challenges of electro-dehydration wastewater pretreatment, achieving a fundamental shift from “difficult to treat” to “stable and efficient.”

Electro-dehydration Wastewater: An Unbearable Burden for Biochemical Treatment

Electro-dehydration wastewater in refineries is a typical high-concentration, hard-to-degrade, highly emulsified industrial wastewater. The core challenges include:

· Stable pollutant structure: Rich in phenols, polycyclic aromatic hydrocarbons, petroleum hydrocarbons, and other complex organic compounds, with stable molecular structures, often resulting in a B/C ratio (biodegradability index) below 0.1, making them unavailable for microbial utilization.

· Biotoxicity suppression: Oils, sulfides, high salt content, and some specific pollutants have a significant inhibitory or toxic effect on microbial communities in the biochemical treatment system.

· Water quality fluctuations: Changes in production conditions frequently cause fluctuations in flow and pollutant concentration, continuously challenging the stability of the treatment system.

Traditional pretreatment processes (such as standard flotation or chemical demulsification) have limited capabilities for degrading these "stubborn" pollutants. A large amount of hard-to-degrade organic compounds and toxic substances enter the biological treatment phase, which is the root cause of low efficiency, high operating costs, and unstable discharge quality.

Technological Breakthrough: How Ozone Pretreatment Transforms the Problem into a Solution

The SINOKLE’s ozone advanced oxidation pretreatment technology is not simply about “removal,” but instead focuses on the “transformation” and “solution” of pollutants through strong oxidative action.

· Core Function 1: Chain-breaking, Improving Biodegradability

Ozone and the hydroxyl radicals (·OH) it generates catalytically can indiscriminately break the chemical bonds of organic compounds, oxidizing large, ring-structured, hard-to-degrade pollutants (such as phenols, benzene compounds) into small molecules like organic acids and aldehydes, which are more easily biodegradable. This process significantly improves the wastewater’s B/C ratio from less than 0.1 to over 0.3, creating a favorable “food source” for subsequent biological treatment. Studies show that ozone pretreatment is a key step in enhancing the biodegradability of hard-to-degrade wastewater.

· Core Function 2: Efficient Demulsification, Breaking Oil Barriers

The strong oxidative effect of ozone effectively destroys the double electrical layers on the surface of emulsified oil droplets and the surfactants that surround them, achieving efficient demulsification and oil-water separation. This not only removes harmful oil that can poison microorganisms but also significantly reduces COD load in the water, removing the primary obstacle for the biological system.

· Core Function 3: Detoxification and Protecting Microorganisms

By degrading sulfides and certain characteristic toxic organic substances, ozone pretreatment effectively reduces the toxicity of wastewater to microorganisms, preserving the activity and diversity of microbial communities in the biological treatment phase, and enhancing the system's capacity to handle shock loads.

The SINOKLE’s Solution: Precision Oxidation for Pretreatment Advantages

Compared to traditional ozone applications, the SINOKLE offers a customized, precise, efficient, and stable pretreatment solution.

· Efficient Mass Transfer Technology: The proprietary high-efficiency ozone mixing and mass transfer technology ensures full contact and efficient dissolution of ozone in the wastewater, avoiding ozone escape and maximizing oxidation efficiency.

· Catalytic Oxidation Enhancement: For electro-desalting wastewater, exclusive catalysts (such as supported metal oxides) can be used to catalyze ozone and generate more highly oxidative hydroxyl radicals, improving the removal efficiency of specific hard-to-degrade pollutants and reducing operational energy consumption.

· Intelligent Dosage Control: Based on online water quality monitoring (such as COD, TOC), the ozone dosage is adjusted intelligently to ensure operation at the optimal economic point, responding to water quality fluctuations, and ensuring stable effluent quality.

Key Technical Parameters and Application Effects (Typical Scenarios)

· Ozone Dosage

Range: 50-150 mg/L

Explanation: Adjusted according to the raw water COD concentration and target; typically, 15-25 mg/L ozone is required per 100 mg/L reduction in COD.

· Reaction Time

Range: 30-60 minutes

Explanation: Ensures complete reaction. High-efficiency mixing methods can reduce the reaction time.

· B/C Ratio Improvement

Before Treatment: Typically < 0.1

After Treatment: Can increase to > 0.4

Explanation: Biodegradability significantly improves, creating favorable conditions for biological treatment.

· Characteristic Pollutant Removal

Phenol Removal Rate: ≥ 90%

Benzene Compound Removal Rate: ≥ 80%

Explanation: Effectively tackles characteristic hard-to-degrade pollutants.

Comprehensive Benefits for Refining Enterprises

By adopting the company’s ozone pretreatment technology, enterprises gain not only improvements in water quality indicators but also a systematic enhancement in the overall process.

· Significant Reduction in Biological System Operating Costs: Pretreatment transforms most of the hard-to-degrade COD into easily biodegradable COD, reducing the biological treatment load by over 40%, significantly lowering aeration energy consumption, sludge disposal costs, and nutrient dosing costs.

· Fundamental Guarantee for Stable Discharge Compliance: The effective removal of toxins and hard-to-degrade substances at the front end significantly improves the stability of the subsequent biological and advanced treatment units, completely eliminating the risk of exceeding discharge standards due to front-end water quality fluctuations.

· High Investment Return Rate: Although a pretreatment unit is added, by reducing the size of subsequent units (e.g., reducing the volume of the biological treatment tank) and saving long-term operating costs, the comprehensive investment return period of the project is typically better than traditional process routes.

· Environmental and Safety Value: Reducing toxic substances at the source reduces environmental risks; the system is highly automated, ensuring safety and ease of operation.