Equinor orders seawater sulphate handling system for Castberg wells

The SUEZ/Halvorsen TEC consortium will deliver a seawater sulphate removal unit (SRU) system to Equinor’s Johan Castberg project in the Barents Sea, after completing a year-long front-end engineering and design (FEED) study.

 

Johan Castberg, 100 kilometre (62 mi)le north of the Snøhvit field, is due to start oil production in 2022.

 

“Working jointly with Halvorsen TEC last year on the FEED study enabled us to showcase really how well this technology would work for them and how we can engineer the design to meet their specific requirements,” said Matt Boczkowski, director of marketing and growth initiative for SUEZ.

 

“Sulphate removal is vital in the protection of production wells and for preventing barium and strontium scale.”

 

The SRU will allow Equinor to inject seawater at less than 20 parts per million of sulphate content and less than 20 parts per billion of oxygen. The system will have an injection capacity of 1,188 cu m/hr, and the full package, to be delivered early in 2020, will include:

 

  • SUEZ’s seawater sulphate-reducing nanofiltration membranes, which are said to eliminate nearly all sulphates from the injection seawater and remove divalent ions from the seawater to prevent barium and calcium scale formation, while leaving monovalent ions such as sodium and chloride to pass through the membranes
  • SUEZ’s ZeeWeed 700B horizontal ultra-filtration system, widely adopted in the desalination industry, for fine solids removal
  • De-oxygenation membrane technology from 3M
  • A full single-lift SRU.

 

The SRU will be installed on Castberg’s FPSO. During production, seawater will be injected into the oil reservoirs to maintain or enhance oil production. However, because low-quality injection water can cause scale and corrosion leading to plugging and souring, the seawater must first be processed.

 

In addition, SUEZ will provide the process guarantee for the entire unit, which is OnBoard and InSight ready. The latter are a service offered and digital technologies said to combine advanced data and analytics to help operators take better business decisions, eliminate unplanned downtime, and reduce operating costs.

 

Implementation of this service will be evaluated closer to the start-up date.

 

Source: Offshore Magazine