From an obituary in the Durban Chess Club Bulletin of July 1973:
"We were sad to notice a recent press announcement that F.B. van Asperen
had died in Port Elizabeth on the 30th June. He was the Club Champion in 1952
and President from December 1954 to March 1955. Van Asperen was a Hollander
who settled in Durban after the war living here for about ten years before
moving to Port Elizabeth."
Unfortunately I have been unable to locate a cross-table for the 1952 event. John Blackburn joined the club in 1952, but his collection of annual reports only starts from 1953. The 1954 SA Chess Federation Yearbook gives the results as F.B.van Asperen 8/10, M.C.Mackessack 7½, M.Kolnik and J.G.Gorodi 7 pts. Van Asperen did not defend his title in 1953 (Kolnik won) and finished =5th in 1954 and 4th in 1955, before leaving Durban.
I found this win by van Asperen in the games column of "The South African Chessplayer"
for the 1954 year. Van Asperen won the First Swiss with 11½ out of 13 and his opponent,
Ray Hill, was a regular in the Durban championship, finishing second in 1954 to Moss Kolnik.
However, he is completely outplayed in this game: