Police say David Alun Lewis lived with his parents in Ystrad Mynach, but would sometimes visit Cardiff and stay at the Huggard Centre.
His parents have paid tribute to him:
This is so sad. We love David so much and our lives will never be the same again.
We can’t believe such a thing has happened to our son.
The last known sighting of Mr Lewis was around 7.45pm on Wednesday walking along Penarth Road near the Big Yellow Storage opposite a BMW garage.
Police are still appealing for witnesses, and say they want to speak to anyone who was near the Taff Embankment between 7.45pm and 11.45pm on Wednesday.
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Feeling humid with heavy showers and thunderstorms moving north overnight into Sunday.
Four people, including three children, were taken to hospital to be checked for smoke inhalation.
Heavy rain and thunderstorms will affect many parts of Wales this weekend - particularly during Saturday evening.