Inlet protection, solids separation, and preliminary wastewater conditioning. The first and most critical stage of every treatment plant, safeguarding downstream processes from damage and overload.
CFD, P&ID, SCADA and commissioning for critical water treatment plants.
Plant layouts, piping isometrics and construction-ready engineering drawings.
Flow, mixing and thermal CFD across treatment and process equipment.
Full mechanical, physico-chemical, biological and sludge equipment range.
Protecting downstream equipment and preparing effluent for biological processing
Primary treatment is the essential first stage that removes coarse solids, grit, and settleable matter before effluent enters secondary biological processes. Without effective primary treatment, downstream equipment suffers accelerated wear, biological reactors become overloaded, and operational costs escalate. Reynolds & Bauhm engineers each primary stage to match your specific influent characteristics and flow regime.
Removes rags, plastics, and coarse solids that would damage pumps, block pipes, and foul downstream equipment. Proper screen selection prevents unplanned shutdowns and costly maintenance.
Separates sand, gravel, and dense inorganic particles that abrade pumps, accumulate in tanks, and reduce effective biological reactor volume over time.
Gravity settling removes settleable organic solids and associated BOD, reducing the load on biological treatment stages and improving overall process efficiency.
Engineered inlet protection and solids separation
Self-cleaning rotary screens for continuous solids removal from municipal and industrial flows. Designed with variable slot sizes from 0.5 mm to 6 mm to match your solids profile.
View Drum ScreensCompact step-type screens for installations with limited footprint. Self-cleaning mechanism with no submerged bearings, reducing maintenance requirements in harsh wastewater environments.
View Step ScreensArchimedean screw-based screening for small to medium flow applications. Compact design with integrated compaction and bagging of screenings for easy disposal.
View Spiral ScreensVortex and aerated grit chambers that separate dense inorganic particles from organic matter. Grit washing and classification ensures clean, dry grit suitable for landfill disposal.
View Grit ClassifiersHigh-rate inclined plate settlers achieving superior solids separation in a footprint up to 90% smaller than conventional clarifiers. Ideal for primary and secondary clarification duties.
View Lamella ClarifiersGravity oil-water separators for industrial effluents containing free oils and hydrocarbons. Corrugated plate coalescers enhance separation efficiency for oil refinery and manufacturing applications.
View API SeparatorsMatching primary treatment equipment to your application
| Application | Recommended Equipment | Slot / Plate Spacing | Typical Removal Efficiency |
|---|---|---|---|
| Municipal Inlet | Coarse screen + fine drum screen | 6 mm + 3 mm | Coarse solids >95% |
| Food Processing | Spiral or drum screen + DAF pre-treatment | 1-3 mm | Organics + FOG >90% |
| Brewery & Beverage | Rotary drum screen + lamella clarifier | 1-2 mm | TSS >85%, BOD >40% |
| Meat & Poultry | Coarse screen + fine screen + DAF | 10 mm + 2 mm | Solids + blood >95% |
| Oil & Gas Refinery | API separator + DAF + lamella | Plate spacing 50-80 mm | Free oil >99%, TSS >90% |
| Mining & Quarry | Static curved screen + grit classifier | 0.5-2 mm | Coarse solids >95% |
| Industrial Pre-treatment | Step screen + lamella clarifier | 3-6 mm | Settleable solids >90% |
| Metro & Tunnelling | Shaker screen + grit removal | 0.25-1 mm | Sediment >95% |
Selection depends on site-specific influent characterisation and flow rate. Pilot testing recommended for complex effluents.
This treatment stage is engineered to achieve specific contaminant removal targets while providing stable, predictable performance across variable inlet conditions. Design parameters are calculated from wastewater characterisation data, regulatory requirements, and site-specific constraints including footprint, energy availability, and operator capability.
Design validated by CFD modelling and pilot testing to confirm performance guarantees.
Equipment selected for 20-year design life with minimal wearing parts and easy access.
Automated dosing and feedback control minimise reagent consumption and sludge production.
Online monitoring and data logging demonstrate continuous consent compliance.
| Design Flow | 10 – 5,000 m³/h (application specific) |
| Inlet Variability | Designed for 1:3 peak-to-average flow ratio |
| Removal Efficiency | 85 – 99% depending on target contaminant |
| Hydraulic Retention | Calculated from kinetic constants and safety factors |
| Power Consumption | 0.5 – 5.0 kWh/100 m³ (process dependent) |
| Chemical Dose | Auto-controlled based on online analysers |
| Sludge Production | 0.2 – 1.5 kg DS/kg contaminant removed |
| Materials | SS304, SS316L, or carbon steel with coating |
No treatment stage operates in isolation. This process is designed to receive conditioned influent from upstream stages and deliver effluent quality suitable for downstream processes. Hydraulic and organic loading rates are balanced across the complete treatment train to prevent bottlenecking and ensure overall plant efficiency. Our engineers model the complete flowsheet to optimise Capital expenditure and Operating expenditure across the plant lifecycle.
Screening, equalisation, and pre-treatment protect this stage from damage and overload.
Effluent quality ensures downstream biology, filtration, or disinfection performs optimally.
Reject streams, filtrate, and centrate are routed back to appropriate upstream points.
Our process engineers will assess your influent profile and recommend the optimal combination of screening, grit removal, and clarification equipment for your application.
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.
Read the API Separators PageCompare the three dominant configurations side-by-side — droplet cut-size, footprint, Operating expenditure and best-fit applications.
Compare Separator TypesCFD-verified F-factor for shorter basins, optimised inlet diffusers and reduced civils Capital expenditure.
CFD EngineeringOur expertise spans multiple industries with sector-specific water treatment solutions.