Eta Process Plant
The world's leading supplier of turnkey deaeration plant


seawater deaeration


Eta's experience in deaeration technology goes back over 35 years to the rapid growth in offshore oil exploration and production in the UK's North Sea.

Today, Eta has over 400 deaeration plants operating in locations ranging from Alaska to Australia that vary in size from 1.5 to 5 m in diameter and providing throughput from 100 to 3,250 m3/hr per tower.


As part of an ongoing commitment to reduce topside weight and footprint size, Eta embarked on an extensive pilot plant test programme at its facilities in the UK. Liquid loading trials were used to determine the effect of 'back mixing' of vapour and liquid channelling.

The result was a unique combination of column packing and internals for water flow rates in excess of 200 m3/m2/hr. The patented BETA RING® packing was a central element of this work and now forms a key part of Eta's deaeration equipment.

Vacuum pump skid as part of a seawater vacuum deaeration package to remove oxygen for an offshore water injection system located on an FPSO

The very first units used gas produced from the field as the stripping medium prior to flaring. However, environmental and financial pressures dictated that some other methodology be adopted. By studying Henry's Law at the operating temperature and pressure, a design model can be simulated using various degrees of vacuum to reduce the oxygen level.

Eta is skilled in its ability to optimise the design with in-house computer programs (developed over many years using feedback from operating units). Height, weight, and power are key to the optimisation process with each one applying to a different extent depending on the location, such as onshore, offshore, fixed platform, or FPSO.

Eta is accomplished in translating the designs and project managing them into a cost effective, fully skid-mounted package plant.

Fine filter package to filter seawater down to 5 microns for an offshore water injection system

Eta Process Plant also designs and supplies package plant solutions for gas scrubbing, oil stabilisers, sour water strippers, oil settling/skim tank internals, distillation units, and applications using engineered plastics in addition to traditional metal materials of construction.

Today, the majority of seawater deaeration plants supplied by Eta use vacuum stripping. Eta's fully skid mounted package plants are easily integrated into the platform topside module.

Eta's scope of supply for package plants has increased from the deaeration plant to include coarse and fine filters, chemical injection and booster pumps together with control panels containing the logic and code to safely operate the whole of the water injection topsides facility.