Advanced advanced biological treatment systems for petroleum refineries removing phenols, sulphides, and dissolved organics to achieve strict COD and BOD discharge limits.
Treat drilling muds, cuttings wash water and site runoff. Solid-liquid separation and water recycling for drilling operations.
Refinery wastewater treatment including API separators, DAF, advanced biological treatment and polishing for strict discharge.
Oil and gas wastewater treatment for produced water treatment.
Sour water and desalter effluent treatment for petroleum refineries.
Biological Removal of Refinery Organics
After oil separation, refinery wastewater still contains high concentrations of dissolved organics, phenols, sulphides, and ammonia that must be removed before discharge. Our advanced biological treatment systems use specialised microbial communities adapted to petroleum hydrocarbons, achieving 90%+ COD removal and <0.5 mg/L phenol concentrations even under variable loading conditions. Reynolds & Bauhm design acclimated activated-sludge, MBBR and MBR systems sized for refinery shock loads and toxic-compound resilience. Robust aeration, nutrient dosing and clarification deliver consistent COD, phenol and ammonia removal even under upset conditions.
MBBR and SBR systems achieve 90%+ COD reduction from typical refinery influent concentrations of 500-2,000 mg/L.
Specialised phenol-acclimated biofilms remove toxic phenolic compounds to <0.5 mg/L meeting strict environmental limits.
Biological sulphide oxidation converts reduced sulphur compounds to elemental sulphur or sulphate preventing toxicity and odours.
Moving bed biofilm reactors tolerate phenol and hydrocarbon shock loads better than conventional activated sludge.
Refinery Biological Treatment Sources
Biological treatment of stripped sour water containing ammonia, phenols, and reduced sulphur compounds after steam stripping.
Treatment of wastewater from delayed coking and fluid coking units with high phenol and COD concentrations.
Biological removal of organics from FCC unit wastewater containing oil, phenols, and sulphides.
Treatment of effluent from hydrotreating and hydrocracking operations with high nitrogen and sulphur content.
Biological polishing of combined refinery wastewater after primary oil separation and clarification.
Treatment of blowdown and drainage from cooling towers, boilers, and utility systems throughout the refinery.
Integrated Biological Treatment Process
Oil separation and clarification protect biological systems from oil toxicity and solids accumulation.
Equalization tanks dampen flow and concentration variations to maintain stable biological conditions.
MBBR or SBR systems remove dissolved organics, phenols, and reduce COD/BOD through biofilm oxidation.
LAMELLA separators settle biological sludge for recycle or wasting, producing clear effluent.
Products for Refinery Biological Treatment
Moving bed biofilm reactors for high-rate COD and phenol removal in compact footprint.
Benefit: 90%+ COD removal
Sequencing batch reactors providing batch advanced biological treatment with built-in settling phases.
Benefit: Flexible operation
High-efficiency diffused aeration systems delivering oxygen for biological oxidation.
Benefit: Energy efficient
High-rate solids separation for secondary clarification and sludge recycle.
Benefit: 70% smaller footprint
Screw presses and centrifuges for biological sludge dewatering to minimise disposal requirements.
Benefit: 60-80% efficiency improvement
Automatic backwash filtration for final suspended solids removal before discharge.
Benefit: Continuous operation
Why Choose Reynolds & Bauhm
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View PageRefinery wastewater treatment including API separators, DAF, advanced biological treatment and polishing for strict discharge.
View PageRefinery biology runs hot, salty and toxic. Standard municipal kinetics do not apply.
Influent typically 30–45°C from stripper/cooling water. Mesophilic biology design at 35–38°C. Cooling tower may be needed to prevent overheating in summer.
Phenols toxic above 100–200 mg/L; sulphide above 50 mg/L; ammonia above 1,500 mg/L. Use acclimated biomass; provide chemical pre-treatment buffer.
0.15–0.30 kg BOD/kg MLVSS·d for refinery streams (lower than municipal). MLSS 3,000–5,000 mg/L. SRT 15–25 days to enable nitrification.
MBBR preferred for retrofit: tolerates shock load, accommodates seasonal variability. CAS preferred for greenfield where space is available.
Specialised phenol-acclimated biomass; SRT ≥20 days; multi-stage to handle shock loads. Polish with GAC or AOP for <1 mg/L residual.
Inhibited by phenol >5 mg/L. Separate nitrification basin downstream of carbon removal. DO >2.5 mg/L, pH 7.0–8.5, alkalinity supplement.
| Parameter | Municipal (reference) | Refinery biological |
|---|---|---|
| F/M (kg BOD/kg MLVSS·d) | 0.20–0.50 | 0.10–0.30 |
| MLSS (mg/L) | 2,500–4,000 | 3,000–5,000 |
| HRT (h) | 4–8 | 12–36 |
| SRT (d) | 5–15 | 15–25 |
| DO (mg/L) | 1.5–2.5 | 2.0–3.5 |
| Phenol max (mg/L) | n/a | <100 with acclimation |
| Effluent BOD (mg/L) | <15 | <25 |
Stokes’-law sizing, API Publication 421 design methodology, rectangular API / CPI / TPI configurations and refinery-train integration.
Sizing, components, types, materials, codes & compliance — the full engineering reference for gravity oil-water separation.
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CFD EngineeringContact our experts to design a biological system tailored to your refinery wastewater.
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