The Ultra MEV is a pre treatment ultrafiltration system designed by Veolia and DuPont Water Solutions, to satisfy offshore critical factors.
Ultrafiltration is a pre-treatment process that replaces media filters and cartridge filters upstream of our SRP / SWRO systems. It provides feed water at a consistent quality and has a number of benefits, reducing weight/size, provides filtration to 0.1 microns and reduces frequency of downtime due to SRP clean in place operations.
Veolia’s UltraMev Ultrafiltration package treats seawater to remove the majority of particles greater than 0.02 µm. The process uses hollow fibre membrane technology in ‘dead-end’ filtration mode without the need for continuous cross flow velocity. The filtrate quality is typically expected to have an SDI < 3.
The hollow fibre is a PVDF membrane, chosen for its robustness and its resistance to the chemicals used during operation to maintain the condition of the membrane. The manufacturing process allows the pore size and distribution to be carefully controlled to provide a pore structure with a defined pore diameter of 0.02 – 0.04µm. This ensures that the membrane captures the bulk of fine seawater particulates including bacteria and most viruses.
The UltraMEV combines multiple ultrafiltration elements in a single housing reducing footprint, weight and need for interconnecting pipework.
Critical benefits for Offshore Water Treatment Plants
- Compact design providing footprint and weight savings
- Simplified UF element change out
- Enhanced integrated membrane warranty
- Reduced SR / SWRO cleaning, giving increased life expectancy for SR / SWRO membranes
- Greater injection system uptime
The MEV (multi element vessel) is designed as a standard pressure vessel to normal design codes and can be rated at any mechanical design pressure. During normal filtration mode, water enters the bottom of the vessel and flow through the length of the fibre to it lumen. The filtrate collects in the top chamber and exists the MEV to discharge to the downstream process. The filtration process works in dead-end mode with no water lost due to 'reject' loss.
