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Example ApplicationDesalination

Seawater RO Pretreatment for Desalination

This is an illustrative scenario showing how Reynolds & Bauhm equipment can be configured for this application. Every site has unique requirements — contact us for a solution tailored to your specific wastewater characteristics.

Process Requirements & Constraints

Open seawater intake for 5,000 m3/day SWRO desalination plant. Raw seawater has SDI 12, turbidity 15 NTU, oil 3 mg/L, and seasonal algae blooms. SWRO membranes require SDI <3 and turbidity <1 NTU. Membrane fouling was requiring monthly CIP, reducing plant availability to 85%.

Key Performance Targets
<3
Final SDI
<0.5
Turbidity NTU
90
Days between CIP
97%
Plant availability
35%
O&M efficiency improvement
5 yr
Membrane life

Treatment Approach

Step-by-step process configuration from raw wastewater to compliant discharge.

01

Coarse Screening & Intake

Travelling water screens at intake remove debris and marine organisms. Chlorination at 2 mg/L prevents biofouling in intake pipeline. Flow measurement and automatic control.

02

DAF Algae & Oil Removal

High-rate DAF with coagulant and polymer dosing removes algae, oil, and suspended solids during bloom events. Achieves consistent effluent turbidity <2 NTU and oil <0.5 mg/L. Protects downstream filtration.

03

Multimedia Filtration

Dual-media anthracite/sand filters operate at 10 m/h filtration velocity. Backwash triggered by headloss or timer. Effluent turbidity <0.5 NTU. SDI reduced to 4-5.

04

Cartridge Filtration

5-micron pleated cartridge filters provide final protection for RO membranes. Differential pressure monitoring triggers change-out at 1 bar. SDI consistently <3 achieved.

05

RO Protection & Results

Complete pretreatment train extends SWRO CIP interval from 30 to 90 days. Membrane replacement interval extended from 3 to 5 years. Plant availability increased to 97%. Annual O&M cost reduced by 35%.

Equipment Configuration

The specific equipment selected for this application, sized for the flow rate and contaminant load.

DAF System

High-rate DAF, 250 m3/h, coagulant/polymer dosing, SS construction, marine-grade coating.

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Media Filter

Dual-media anthracite/sand, 3.0 m diameter, 10 m/h velocity, automatic backwash.

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Cartridge Filter

5-micron pleated cartridges, 8x40 inch, stainless steel housing, differential pressure monitoring.

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Chlorine Dosing

Sodium hypochlorite day tank, metering pump, residual chlorine analyser.

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Performance Achieved

Representative performance data based on typical operating conditions for this equipment configuration.

<3
Final SDI
<0.5
Turbidity NTU
90
Days between CIP
97%
Plant availability
35%
O&M efficiency improvement
5 yr
Membrane life

Related Equipment

Explore the full range of equipment used in this and similar applications.

RO Skid

SWRO membrane system for seawater desalination.

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Dechlorination System

Sodium bisulfite dosing to protect RO membranes from chlorine.

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pH Correction

Sulphuric acid dosing for RO feed pH and scale control.

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Scale Inhibitor Dosing

Antiscalant dosing to prevent calcium sulphate precipitation on membranes.

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Related Treatment Processes

Discover how these treatment processes connect to form complete wastewater treatment solutions.

Project Approach & Engineering

Reynolds & Bauhm follows a structured engineering methodology for every project. We begin with detailed wastewater characterisation, process selection based on contaminant profiles, pilot testing where required, and full-scale design with performance guarantees. Our multidisciplinary team of chemical, mechanical, and electrical engineers ensures seamless integration of process, mechanical, and control disciplines.

Characterisation

Comprehensive influent analysis including COD, BOD, TSS, heavy metals, pH, temperature, and flow profiling.

Process Design

Process flow development with P&IDs, mass balances, and hydraulic modelling validated by CFD where appropriate.

Pilot Testing

On-site pilot trials validate performance guarantees under actual operating conditions before capital commitment.

Commissioning

FAT, SAT, performance trials, operator training, and handover documentation ensuring operational readiness.

Equipment Configuration

Pre-TreatmentScreening, grit removal, and flow equalisation
Primary TreatmentDAF or lamella clarification for solids and oil removal
Secondary TreatmentBiological oxidation (activated sludge, MBBR, or SBR)
Tertiary TreatmentFiltration, UV disinfection, or chemical polishing
Sludge ManagementThickening and dewatering via belt press or centrifuge
Control SystemPLC with HMI touchscreen and optional SCADA integration
Chemical DosingAutomated coagulant, flocculant, and pH correction
MaterialsSS316L, duplex, or rubber-lined carbon steel

Performance Outcomes

COD Removal

85 – 98% chemical oxygen demand reduction depending on process configuration and influent variability.

TSS Removal

90 – 99% suspended solids reduction through combined physical and biological treatment stages.

Water Reuse

Tertiary treatment enables up to 80% water recycling for non-potable process applications.

Apply This Configuration to Your Site

Our engineers will adapt this equipment configuration to your specific wastewater analysis, flow rate, and discharge requirements.

Multimedia Filter — Technical Library

For the depth-filtration step in this process we use multimedia filters with graded anthracite/sand/garnet beds. The technical detail behind sizing, media specification, backwash hydraulics and field troubleshooting lives in a dedicated library — pick the topic:

Industries We Serve

Our expertise spans multiple industries with sector-specific water treatment solutions.