Anderson was employed by services company Cape and was part of a team carrying out routine maintenance on the normally unmanned riser facility.
His identity was released by his employer on Friday afternoon.
Cape’s UK managing director Simon Hicks said: “We remain shocked and saddened by what happened yesterday. Our thoughts are with Sean’s family whom we will support in any way we can.
“Sean was a popular, hard-working and experienced employee. His co-workers are obviously shaken and saddened by the incident and we are making sure they too have all the support they need.
“We don’t know how or why this incident happened but we will co-operate fully with Police Scotland and the Health & Safety Executive (HSE) in their investigation.”
Police in Aberdeen said they were made aware of the death at about 4.40am yesterday.
It is understood Anderson died after falling from the platform at about 4.10am, but this has not yet been confirmed.
Police have launched an investigation and are liaising with the HSE.
Anderson’s next of kin were informed on Thursday.
BP said on Thursday it was working with Police Scotland, the HSE, Cape and other relevant organisations to support relatives and Anderson’s co-workers and ensure the incident is fully investigated.
Unity is located 182 kilometres east-north-east of Aberdeen is a normally unmanned pumping facility that forms part of the Forties Pipeline System, allowing connections from the Bruce, Scott, Nelson, Britannia and Graben Area Export Line fields, including Shearwater and Elgin.