Wastewater Treatment Process for Heavy Oil Power Stations
As an important energy supply facility, a heavy oil power station generates large amounts of oily wastewater during operation, mainly from oil tank farm drainage, floor washing water, equipment maintenance drainage and possible accidental spills. Such wastewater typically has a high oil and grease content (especially heavy oil and emulsified oil), a complex composition (possibly containing suspended solids, colloids, some dissolved organics and heavy metals) and high variability. Conventional processes such as oil separation and coagulating sedimentation often struggle to achieve stable and efficient oil-water separation, and the effluent quality can hardly meet increasingly stringent discharge standards or reuse requirements, bringing environmental pressure to enterprises while also wasting water resources.
Innovative solution: CDFU a powerful combination of cyclonic dissolved-air flotation and KFM active filter media filters
In response to these industry challenges, the SINOKLE environmental technology team conducted in-depth research into on-site needs and creatively introduced the integrated treatment route of "CDFU cyclonic dissolved-air flotation unit + KFM active filter media advanced filtration unit", forming a complete solution covering pre-treatment and advanced purification.
First line of defence: CDFU cyclonic dissolved-air flotation - the core of efficient demulsification and oil droplet removal
CDFUThe cyclonic dissolved-air flotation system is one of SINOKLE's core patented technologies. It cleverly combines cyclone separation technology with efficient dissolved-air flotation technology, creating unique treatment advantages:
Efficient cyclone pre-separation: the influent first enters the cyclone section, where, under a strong centrifugal force field, most of the free oil and larger-density suspended solids in the wastewater are rapidly and initially separated, reducing the load on the subsequent flotation unit.
Precise micro-nano bubble flotation: the pre-separated wastewater enters the dissolved-air flotation section. Through an efficient dissolved-air system, the system generates large quantities of dense, uniform micro-nano bubbles. These bubbles fully collide with and adsorb onto the fine oil droplets, emulsified oil and colloidal substances in the wastewater after chemical conditioning (such as demulsification and coagulation), forming "bubble-particle" complexes.
Rapid solid-liquid separation: under buoyancy, the complexes quickly rise to the water surface to form a stable scum layer, which is periodically removed by a scraper. Its separation efficiency is far higher than that of conventional air flotation, with particularly notable results in the demulsification and separation of difficult-to-treat emulsified oil.
Compact design and stable operation: CDFU The system has a compact structure, a small footprint, a high degree of automation, stable operation and strong shock-load resistance, making it highly suitable for treating oily wastewater from power stations with large fluctuations in water quality and volume.
After treatment by the CDFU unit, the vast majority of floating oil, dispersed oil and emulsified oil in the wastewater is effectively removed, and the effluent oil content and suspended solids concentration are greatly reduced.
Second line of defence: KFM active filter media filter - advanced purification and water quality assurance
To ensure that the effluent quality reaches a higher standard (such as reuse as make-up water for circulating cooling water systems or plant landscaping) or meets the strictest discharge limits, SINOKLE installs a KFM active filter media filter after the CDFU as an advanced treatment unit. KFM active filter media is a composite filter medium that has undergone special process modification and possesses multiple surface characteristics:
Fine physical interception: the filter bed formed by the filter media particles effectively intercepts CDFU the trace amounts of fine suspended solids and colloidal substances remaining in the effluent.
Adsorption and purification function: the surface of KFM filter media has abundant pore structures and active sites, with a significant adsorption effect on dissolved organics, some heavy metal ions and residual trace oil, further improving the removal rates of COD, BOD and specific pollutants.
Hydrophilic and oleophobic characteristics: special surface modification gives it good hydrophilic and oleophobic performance, so it is not easily clogged by oil contamination, extending the service life of the filter media and providing good backwash regeneration.
Simple operation and maintenance: the filter adopts automated control and can automatically carry out backwashing according to pressure difference or time, making maintenance and management simple.
Through the advanced adsorption and filtration of the KFM active filter media filter, the effluent is clear and transparent, and key pollutant indicators such as petroleum-based substances, suspended solids and COD can stably reach or even exceed the Grade I standard of the Integrated Wastewater Discharge Standard (GB 8978-1996) or the relevant reuse water standards.
Application results: a win-win for economic and environmental benefits
This combined process has been successfully applied in several new-build or retrofit projects for oily wastewater treatment at heavy oil power stations. Operating data show:
Outstanding treatment performance: the system achieves an overall removal rate of over 99.5% for petroleum-based substances and over 98% for suspended solids, with the effluent petroleum-based concentration stably below 3 mg/L, even reaching below 1 mg/L.
Low operating cost: the system is highly integrated with low energy consumption; chemical dosage is optimised thanks to efficient air flotation; and KFM filter media have a long service life, with a replacement cycle far better than ordinary filter media.
Resource utilisation: the treated effluent can be reused as required, saving fresh water resources and reducing power station operating costs.
Environmental compliance assurance: the difficulty of achieving compliant discharge of oily wastewater is completely resolved, avoiding environmental risks and enhancing the enterprise's social image.
About SINOKLE
SINOKLE is committed to being a leading provider of innovative technologies and solutions in the field of water treatment. The company continuously invests in research and development and holds multiple core patented technologies. Its products and services cover industrial wastewater treatment, municipal wastewater upgrading and retrofitting, water supply purification, water environment remediation and other fields. In the future, SINOKLE will continue to be driven by technological innovation, providing global customers with more efficient, more economical and more reliable environmental products and services, and contributing technological strength to protecting green mountains and clear waters and building a beautiful China.
