ENVI-Marine™ is a seawater scrubbing system that uses the patented ENVI-Clean™ scrubbing head to provide a highly interactive turbulent zone between seawater and the marine exhaust gases.

The turbulent zone provides the energy and residence time to remove SO2 and a significant portion of particulate matter in a compact and flexible footprint. The International Maritime Organisation and European Community have established harmonized regulations in Sulphur Emission Control Areas that require lower sulphur emissions as can be delivered by the ENVI-Marine™ seawater scrubbing system.

Technical Description

The ENVI-Marine™ system has three areas of interaction – the quench zone, the patented turbulent scrubbing head and the pack bed media.

The system functions by:

  • Using the natural alkalinity of seawater to absorb SO2 emissions produced by marine engines
  • Post treatment discharge of neutralized sulphur into sea
  • Using caustic soda (NaOH) as a supplemental reagent when transiting areas with low seawater alkalinity

The system has a flexible layout allowing for:

  • Potential for component separation
  • Able to configure footprint to fit space available
  • Compact footprint



Aframax - 310 days
Suezmax - 285 day

System Operating Modes

The ENVI-Marine™ system is designed to operate in three modes, Open, Closed and Hybrid depending on the sea’s alkalinity and the effluent emission regulations of the waters in which the ship is located.

Open Mode – single pass raw seawater.  Seawater returned to sea following treatment.

Closed Mode – water is recirculated with NaOH added to neutralize sulphur. No discharge while in port. Solution is processed and contaminants are stored for disposal ashore.

Hybrid Mode –  NaOH is added to segments of open system to maintain SO2 removal efficiency in areas of low alkalinity.

Removal efficiency is directly related to thoroughness of interaction and residence time of exhaust gas and seawater.

If you are part of the marine sector and interested in ENVI-Marine, please also take a moment and visit our Pacific Green Marine Technologies website.


Other Technologies


ENVI-Clean™ is a patented Emissions Control System designed to remove pollutants from flue gases. It is suitable for the removal of acid gases and particulate matter from high volume processes such as coal fired power stations, diesel engines and biomass combustion.

Waste to Energy

The ENVI-Pure™ system is an enhanced version of the ENVI-Clean™ system. This version has been designed to remove a broader range of contaminants with extremely high efficiency as required by Waste to Energy (WtE) and Biomass power plants.