Case Study - Sour Water Sample Conditioning System (SWSCS™)

Context

Chemical service companies deal with a lot of challenges for effective CDU overhead and desalter treatment programmes. Online analyzers for sour-water parameters, used for timely optimisation of corrosion-control chemistry, are now gaining traction. SWSCS™ complements these programmes by conditioning the sour-water sample — removing solids, corrosion products, hydrocarbons and H₂S — to improve analyzer reliability and provide consistent, representative data for process and corrosion management.

The challenge

CDU overhead corrosion is a common issue faced by most refiners, and one that is challenging to control. Reliable online monitoring of boot water parameters — such as pH, chloride, ammonia and iron — is critical for timely adjustment of operating conditions and corrosion-control chemistry, helping keep the CDU overhead system within its safe operating window.

Problems arise because the sour-water stream often contains corrosion products, suspended solids, hydrocarbons and dissolved hydrogen sulphide (H₂S). This makes reliable online analysis prone to:

• Frequent analyzer failures and inaccurate measurements.
• Increased maintenance.
• Safety concerns from H₂S exposure.

The solution

The Integrated Sour Water Sample Conditioning System (SWSCS™) has been developed to provide a clean, representative and safe sample for continuous online analysis — significantly improving analyzer reliability and supporting effective overhead corrosion control.

The system is custom designed to fit the compact footprint available at most sites while still providing a reasonable element change-out frequency. It is a skid-mounted unit with a single stage for removal of suspended solids, corrosion products and free and dispersed hydrocarbons, followed by a fixed-bed H₂S scavenging cartridge for safe sample conditioning — allowing continuous delivery of a representative sample to online analyzers.

Key benefits

Improved reliability

• Reduces analyzer fouling and blockage.
• Improves sample consistency.
• Extends analyzer service intervals.
• Minimises unplanned maintenance.

Enhanced safety

• Reduces H₂S concentration prior to analyzer panels.
• Minimises operator exposure during maintenance.
• Reduces release of hazardous gases.
• Improves overall analyzer house safety.

Lower operating costs

• Reduced analyzer downtime.
• Lower maintenance frequency.
• Extended life of analyzer components.
• Reduced replacement-parts inventory.

Product highlights

• Compact, refinery-duty construction.
• Continuous online operation.
• Low pressure drop.
• Replaceable H₂S scavenger cartridge.
• Engineered for hazardous-area installations.
• Customisable to suit client requirements.

What we did