A New Breakthrough in Coking Wastewater Treatment: SINOKLE's Purely Physical Process Achieves Efficient Demulsification, Oil Removal and Purification
How hard is coking wastewater to treat? Consider a set of figures: coking wastewater has a COD as high as 3,000-3,800 mg/L, a phenol content of 600-900 mg/L, ammonia nitrogen of about 300 mg/L, and also contains cyanide, oils and many other pollutants. Based on a national machine-coke output of 70 million tons, this generates as much as 45,000 tons of COD and 3,500 tons of ammonia nitrogen every year. Discharged without treatment, the damage to the environment would be immeasurable.
In recent years, as the "Emission Standard of Pollutants for the Coking Chemical Industry" has been tightened, coking enterprises face mounting environmental pressure. Conventional treatment processes can no longer meet increasingly strict discharge requirements, and coking wastewater treatment has become a recognized "hard nut to crack" in the industry.
Treatment Difficulties
Coking wastewater is difficult to treat mainly in the following respects:
First, pollutant concentrations are high. Coking wastewater has an extremely high organic load — hundreds to a thousand times that of ordinary domestic sewage. Such ultra-high COD means treatment difficulty grows geometrically.
Second, the composition is complex. The wastewater contains not only toxic and harmful substances such as phenols, ammonia nitrogen and cyanide, but also large amounts of emulsified oil. Phenolic compounds strongly inhibit microorganisms, which limits the effectiveness of conventional biological treatment.
Third, emulsification is severe. During coking production, oils in the wastewater mix thoroughly with surfactants to form a highly emulsified oil-water emulsion with extremely fine droplets (usually below 10 microns), which conventional oil-intercepting equipment struggles to separate effectively.
Fourth, treatment costs are high. Conventional processes require large doses of chemical reagents such as flocculants, demulsifiers and pH adjusters, which not only drive up operating costs but also generate large amounts of sludge and cause secondary pollution.
Shortcomings of Conventional Technology
In the past, coking wastewater treatment mainly used a combined "physicochemical + biological" process. The physicochemical stage removed some pollutants by adjusting pH and dosing flocculants, while the biological stage used microorganisms to degrade organics. However, this conventional process has obvious shortcomings:
High reagent consumption: large amounts of chemical reagents must be dosed continuously, keeping operating costs high
High sludge output: chemical methods produce large volumes of heavy-metal-bearing sludge that is difficult to dispose of
Unstable treatment performance: when water quality fluctuates, the biological system easily collapses
Risk of secondary pollution: reagent residues and sludge may cause secondary pollution
Difficulty meeting discharge limits: as standards tighten, conventional processes are increasingly stretched
SINOKLE's New Process
Addressing the industry's pain points in coking wastewater treatment, SINOKLE Technology Co., Ltd. has introduced a purely physical advanced treatment solution that breaks through the limits of conventional chemical treatment.
Core Technology One: CDFU Cyclonic Dissolved Air Flotation Unit
CDFU The unit combines cyclonic separation with dissolved air flotation, generating ultrafine bubbles of 5-30 microns that efficiently capture emulsified oil droplets. Compared with conventional flotation equipment, CDFU its bubbles are smaller and its specific surface area larger, greatly improving oil removal efficiency.
Core Technology Two: KHC Coalescing Oil Separator
By exploiting the coalescing effect of special materials, it lets tiny oil droplets dispersed in water gradually coalesce into large oil beads that are easier to separate downstream. This is particularly effective for treating highly emulsified coking acid water.
Advantages of the Purely Physical Process
Compared with conventional chemical treatment, SINOKLE's purely physical process offers clear advantages:
No chemical reagents: secondary pollution is avoided at the source
High waste-oil recovery: purely physical separation achieves a waste-oil recovery rate above 99%
Low operating cost: no continuous chemical purchases are needed, so long-term operating costs are lower
Enclosed operation: prevents waste gas leakage and improves the working environment
Strong adaptability: insensitive to water-quality fluctuations, running stably and reliably
Application Case
Coking acid water treatment project at a chemical enterprise in Henan
The coking wastewater produced by this enterprise is highly emulsified and highly acidic, and conventional processes had long delivered unsatisfactory results. SINOKLE applied its purely physical process for advanced treatment; the treated effluent is clear and transparent, all indicators improved markedly, and genuine cleaner production was achieved.
The project not only solved an environmental problem that had long troubled the enterprise, but also generated additional economic benefits by recovering waste oil — a win-win for environmental and economic performance. The arrival of the purely physical process gives the industry an entirely new way to solve the problem: efficient treatment without chemical reagents.
