Maersk issued a design standard for a new produced water treatment plant for the platform, stipulating a maximum noise level for the pumps of 80db(A).
This is stricter than the generally accepted maximum level for continuous exposure to noise over an eight-hour working day of 85db(A), Amarinth claims.
Alderley, the produced water treatment plant supplier, commissioned Amarinth to supply the API 610 OH2 pumps with Plan 53B seal support systems complying with the noise restrictions.
On examination, the motor noise was less than 80db(A) but the wetted-end was higher, taking the overall noise levels above the 80db(A) design standard.
The solution was to design a bespoke baseplate placing the pump and motor on the left and the seal support system with its air cooled piping on the right. This allowed Amarinth to design a compact acoustic enclosure for just the wetted end of the pump that would fit within the space constraints of the rig, allowing for regular maintenance and reducing the overall noise to the required level.
To further ease maintenance by providing full 360° access to the pump and motor, the acoustic enclosure was quickly removable without the need to disrupt any pipework. However, it also had to remain in situ near the pumps when removed as there was nowhere else to relocate it to on the rig.
This required modeling during the design stage to determine how staff could work around the enclosure effectively. A maintenance hatch was also provided in the enclosure, allowing regular access to the oiler.