How can solid-liquid separation improve wastewater handling in oxy-hydrochlorination processes?

Oxy-hydrochlorination (OHC) is a key process step in the production of ethylene dichloride (EDC), an essential intermediate in polyvinyl chloride manufacturing. In this process, ethylene reacts with hydrogen chloride and oxygen over a copper-based catalyst to form EDC, enabling efficient chlorine utilisation within integrated vinyls production.

Alongside the main reaction, the OHC process generates wastewater streams containing fine catalyst particles and chlorinated organic compounds such as 1,2-EDC and chloroform. These effluents are chemically aggressive, corrosive, and environmentally sensitive, requiring reliable solid-liquid separation prior to downstream treatment or reuse.

Filtration challenge in OHC wastewater streams

The presence of fine copper-clay catalyst solids in combination with chlorinated media places high demands on filtration equipment. Conventional separation technologies may suffer from corrosion, limited solids removal efficiency, or inadequate containment, increasing operational risk and maintenance effort.

Effective removal of catalyst fines is essential to:

  • Protect downstream wastewater treatment and water reuse systems
  • Reduce catalyst-related fouling and scaling
  • Ensure safe handling of hazardous process media

FUNDABAC® solution for catalyst solids removal

For this duty, the FUNDABAC® candle filter is applied to remove fine copper-based catalyst solids from OHC wastewater streams. The system is designed to operate as a fully enclosed pressure filter, providing stable separation performance under aggressive chemical conditions.

Key design and operational features include:

  • Closed system design, minimising operator exposure to chlorinated liquids and vapours
  • High chemical resistance, with materials selected for corrosive OHC environments
  • Dry cake discharge, enabling safe solids handling and reduced waste volume
  • High solids removal efficiency, supporting reliable downstream treatment and water reuse

By combining robust mechanical design with proven candle filtration technology, FUNDABAC® filters support safe, efficient, and compliant wastewater management in oxy-hydrochlorination units.