Dr Alhajouj and his colleagues were freed on Tuesday
Palestinian-born Dr Ashraf Alhajouj, held for eight years along with five Bulgarian nurses, said he was given electric shocks to his genitals.
The doctor, a Bulgarian citizen, told Dutch TV how police dogs were set on him, but he was later forced to pretend that he had been treated well.
The six medics were freed on Tuesday and have been pardoned in Bulgaria.
Dr Alhajouj and the five nurses - who initially faced the death penalty before their sentences were commuted to life imprisonment - all denied the charges against them.
In an interview conducted in Arabic on Dutch TV's Eenvandaag programme, Dr Alhajouj said the Libyan authorities had drugged him and attached electrodes to his feet and genitals.
"They asked me how many days it had been since I had eaten, I said four days - I thought they were being compassionate," he was quoted as saying by the Associated Press.
The Libyans then said "roasted chicken", before tying his arms and legs to a metal bar and spinning him around like a chicken on a rotisserie, the doctor said.
He said some of the cells they were held in were so hot he could peel the skin from his forehead.
The six medics were arrested in Benghazi in February 1999 and eventually convicted in a Libyan court of knowingly infecting 438 children with HIV, the virus that causes Aids.
The EU's External Affairs Commissioner, Benita Ferrero-Waldner, made many trips to Libya in an attempt to secure their release.
France stepped up the diplomatic effort this month by sending Cecilia Sarkozy, the wife of President Nicolas Sarkozy.
The medics were released from Libyan custody on Tuesday and flown to Bulgaria, where they were pardoned by Bulgarian President Georgi Parvanov.Dr Alhajouj was made a Bulgarian citizen while he was in detention.